Immune

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Non-lymphocytes or granulocytes (WBCs)

1) Basophils 2) Eosinophils 3) Neutrophils 4) Macrophages (MO) 5) Dendritic Cells

How are antibodies made?

1) DNA of undifferentiated B cell - DNA is cut out to form the 2) DNA of differentiated B cell 3) pre-MRNA -spliced out introns ot get here 4) mRNA cap-poly A attached 5) Light chain polypeptide with variable and constant region

Stem cells differentiate into

1) Erythrocytes (RBCs) 2) Leukocytes (WBCs) 3) Thrombocytes (platelets)

What are the two defense systems of the body?

1) Innate Immunity (Non-specific defense) - function against all antigens - first or second LOD 2) Acquired Immunity (Specific Defense Immune System Responses) - responses against a SPECIFIC antigen. final 3rd line of defense

What are the functions of antibodies?

1) Neutralize foreign substances - binds to and masks or inactivates dangerous parts of microbes, toxins, etc. Ex. binds toxin - so toxin can't bind cell and cause damage Ex. binds Ag on microbe and prevents microbe from attaching to or entering host cell 2) Agglutinates cell (clumps) - once agglutinated, cells can be more easily phagocytized by MO and neutrophils -agglutination occurs because Abs have 2 Ag binding sites ex. agglutinates bacterial cells which clumps them together allowing easier phagocytosis 3) Enhances phagocytosis - Ab binds microbes; MO and neutrophils have receptors that can bind to the constant region of the Ab. MO/neutrophils-Ab-microbe interaction make it easier for the WBC to engulf the microbe - showing connection between surface of antibody and macrophage 4) Activates a series of proteins called complement (they complement the activity of antibodies). Complement proteins participate in many aspects of our IS. One of their main functions is to cause lysis of an invading microbe. Complement proteins bind to antibodies that are already attached to the surface of the microbe. This triggers a Cascade of events that ultimately leads to some of these complement proteins embedding themselves into the membrane of the microbe. the embedded proteins from a pore, which caused cell lysis. Complement Cascade can produce chemicals that form pores in the microbe cell membrane, chemicals that attract other macrophages and stimulate phagocytosis of a pathogen.

What is the body's response to histamine?

1) Stimulates production of mucus from epithelial cells = congestion 2) Causes smooth muscle contraction, which can close off bronchial airways 3) BV dilate and become more permeable - causes loss of fluid from vessels and redness area 4) stimulates nerve endings, and, along with other chemicals, can cause itching and pain

Describe the process of diapedesis inflamm response 2LOD

1) Tissue injury, release of chemical signals like histamine and prostaglandins 2) Vasodilation to get increased blood flow; increased vessel permeability; phagocyte migration 3) Phagocytes (macrophages and neutrophils) consume pathogens and cell debris; tissue heals

Describe the steps of Cell-Mediated Immunity

1) a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a target cell via its TCR with the aid of CD8. This interaction, along with cytokines from helper T cells, leads to the activation of the cytotoxic cell 2) The activated T cell releases perforin molecules, which form pores in the target cell membrane, and proteolytic enzymes (granzymes), which enter the target cell by endocytosis 3) The granzymes initiate apoptosis within the target cells, leading to fragmentation of the nucleus, release of small apoptotic bodies, and eventual cell death. The released cytotoxic T cell can attack other target cells

What are the steps of the activation of a Helper T Cell? Th cell

1) after a dendritic cell engulfs and degrades a bacterium, it displays bacterial antigen fragments (peptides) complexed with MHC II molecule on the cell's surface. A specific helper T cell binds to the displayed complex via its TCR with the aid of CD4. This interaction promotes secretion of cytokines by the dendritic cell 2) Proliferation of the T cell, stimulated by cytokines from both the dendritic cell and T cell itself, gives rise to a clone of activated helper T cells all with receptors for the same MHC-antigen complex 3) The cells in this close secrete other cytokines that help activate B cells and cytotoxic T cells

What are the steps of humoral immunity?

1) after a macrophage engulfs and degrades a bacterium, it displays a peptide antigen complexed with a class MHC II molecule. A helper T cell that recognizes the displayed complex is activated with the aid of cytokines secreted from the macrophage, forming a clone of activated Th cells. 2) A B cell that has taken up and degraded the same bacterium displays class MHC II-peptide antigen complexes. An activated helper T cell bearing receptors for the displayed antigen binds to the B cell. This interaction with the aid of cytokines from the T cell, activates the B cell 3) The activated B cell proliferates and differentiates into memory B cells and antibody-secreting plasma cells. The secreted antibodies are specific for the same bacterial antigen that initiated the response

What is the treatment for Anaphylaxis?

1) antihistamine: competes with histamine for receptors on cells (blocks histamine binding) 2) epinephrine: used in severe cases - counters the inflammatory response ex. constructs BV and BP rises

Antibody diversity is due to ?

1) multiplicity of VJ gene segments and their random rearrangement 2) random recombination of L and H chains

What are the symptoms of the Inflammatory Response (as in a wound response) in 2LOD?

1) redness/heat --> increased circulation 2) swelling --> fluid and WBcs 3) Pus --> dead WBCs, dead bacteria, dead cells

Allergies involve what kind of cells?

(1) mast cells, which are non-circulating basophils found in body tissue (b) IgE antibodies

What are the parts of the first line of defense in innate immunity?

(a) Physical barriers - skin, mucus mebranes (throat and alimentary canal), cilia, hair - bacteria, cuticles, dead skin (b) Chemical barriers - enzyme (lysozyme) - in tears, saliva, and sweat breaks down bacteria cell walls; stomach acid - ex. bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes

What are the two types of barriers in first line of defense?

(a) Physical barriers - skin, mucus mebranes (throat and alimentary canal), cilia, hair - bacteria, cuticles, dead skin (b) Chemical barriers - enzyme (lysozyme) - in tears, saliva, and sweat breaks down bacteria cell walls; stomach acid - ex. bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes

What are the parts of innate immunity?

(a) Physical barriers - skin, mucus mebranes (throat and alimentary canal), cilia, hair - bacteria, cuticles, dead skin (b) Chemical barriers - enzyme (lysozyme) - in tears, saliva, and sweat breaks down bacteria cell walls; stomach acid - ex. bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes (c) Phagocytosis - engulfing of microbes/antigens by macrophages (MO) and neutrophils (types of phagocytic WBC that possess many lysosomes) (d) Inflammatory Response (as in a wound response) - local protective response to tissue injury or infection - designed to destroy or wall off injured or infected area Involves: 1. histamine - released from injured cells - dilates vessel and increases blood vessel permeability so that the WBCs and fluid escape from blood - increases circulation in the area 2. other chemicals released from injured cells and microbes attract WBCs to area - WBCs can then phagocytize and digest the microbes 3. Blood clot formation - prevents hemorrhage Symptoms: 1) redness/heat --> increasd circulation 2) swelling --> fluid and WBcs 3) Pus --> dead WBCs, dead bacteria, dead cells (e) Interferon - protein that is active against viral infection - released from virus infected cells and stimulates surrounding cells to resist the viral infection (interferon doesn't kill the virus (f) Fever - increases our cell metabolism bc chemical reactions are increasing - kills microbes that are sensitive to higher body temperature

What is active immunity produced by?

(a) infection with Ag (b) vaccination - administer altered or killed microbe or just pieces of the microbe

What is passive immunity produced by?

(a) injection of antiserum containing Abs ex. snake bite antiserum (b) Abs transferred from female to baby via placenta or in breast milk

What are the parts of 2LOD?

(c) Phagocytosis - engulfing of microbes/antigens by macrophages (MO) and neutrophils (types of phagocytic WBC that possess many lysosomes) (d) Inflammatory Response (as in a wound response) - local protective response to tissue injury or infection - designed to destroy or wall off injured or infected area Involves: 1. histamine - released from injured cells - dilates vessel and increases blood vessel permeability so that the WBCs and fluid escape from blood - increases circulation in the area 2. other chemicals released from injured cells and microbes attract WBCs to area - WBCs can then phagocytize and digest the microbes 3. Blood clot formation - prevents hemorrhage Symptoms: 1) redness/heat --> increasd circulation 2) swelling --> fluid and WBcs 3) Pus --> dead WBCs, dead bacteria, dead cells (e) Interferon - protein that is active against viral infection - released from virus infected cells and stimulates surrounding cells to resist the viral infection (interferon doesn't kill the virus (f) Fever - increases our cell metabolism bc chemical reactions are increasing - kills microbes that are sensitive to higher body temperature

What is used in 3rd line of defense

- (Th) T-helper cells - Tc Cytotoxic T Cells - B Cells - Plasma Cells - Antibodies

How does Ab enhance phagocytosis?

- Ab binds microbes; MO and neutrophils have receptors that can bind to the constant region of the Ab. MO/neutrophils-Ab-microbe interaction make it easier for the WBC to engulf the microbe - showing connection between surface of antibody and macrophage

What happens during the first exposure to an allergen?

- IgE is produced in response to an allergen - IgE constant region binds to mast cells, and the person becomes sensitized (sensitive to another interaction with the same substance)

What are all the kinds of T cells?

- T Helper Cells (Tn) - Cytotoxic T Cells (Tc) - Suppressor T Cells - NKT Cells - "Natural Killer"

What happens during the second exposure to an allergen?

- allergens bind and cross-link two Abs that are already bound to mast cells. This causes the mast cell to degranulate (release its granules, including histamine and other potent chemicals) - histamine causes many of the allergy symptoms by binding cells and inducing a response ex. inflammation, bronchial constriction, BV dilation, pain, and itching

How can antibodies neutralize foreign substances?

- binds to and masks or inactivates dangerous parts of microbes, toxins, etc. Ex. binds toxin - so toxin can't bind cell and cause damage Ex. binds Ag on microbe and prevents microbe from attaching to or entering host cell

What is the variable region of the polypep H and L chains?

- forms 2 identical antigen binding sites -varies from Ab to Ab --> determines which epitope it will bind to

What is the role of fever in 2LOD inflamm response?

- increases our cell metabolism bc chemical reactions are increasing - kills microbes that are sensitive to higher body temperature

Active Immunity

- involves production of immune responses - produces memory cells and is long-lasting - active immunity is produced by: (a) infection with Ag (b) vaccination - administer altered or killed microbe or just pieces of the microbe

What happens during the inflammatory response as in wound response in 2LOD?

- local protective response to tissue injury or infection - designed to destroy or wall off injured or infected area Involves: 1. histamine - released from injured cells - dilates vessel and increases blood vessel permeability so that the WBCs and fluid escape from blood - increases circulation in the area 2. other chemicals released from injured cells and microbes attract WBCs to area - WBCs can then phagocytize and digest the microbes 3. Blood clot formation - prevents hemorrhage Symptoms: 1) redness/heat --> increasd circulation 2) swelling --> fluid and WBcs 3) Pus --> dead WBCs, dead bacteria, dead cells

Passive Immunity

- no memory cells and is short lived - examples of passive immunity include (a) injection of antiserum containing Abs ex. snake bite antiserum (b) Abs transferred from female to baby via placenta or in breast milk

1970s - Jenner and Immunization of Smallpox

- noticed milkmaids that had been exposed to cowpox didn't get smallpox - hypothesized that if get cowpox, then will be protected from smallpox - Jenner injected cowpox into patient and the patient acquired immunity to smallpox this is because both share similar antibodies

How can an Ab agglutinate the cell?

- once agglutinated, cells can be more easily phagocytized by MO and neutrophils -agglutination occurs because Abs have 2 Ag binding sites ex. agglutinates bacterial cells which clumps them together allowing easier phagocytosis

What is the role of an interferon in 2LOD?

- protein that is active against viral infection - released from virus infected cells and stimulates surrounding cells to resist the viral infection (interferon doesn't kill the virus

The constant region of H chain only

-determines class of AB (there are 5 different classes of Ab) - the class or kind of AB --> determines its function, or what the antibody can do once it has bound to the antigen

What are the effects of histamine in inflmmator response in 2LOD?

-dilates vessel and increases blood vessel permeability so that the WBCs and fluid escape from blood - increases circulation in the area

What are cytokines

-hormone-like molecule secreted from cells of the immune system. They have many effects on immune cells and other cells of the body; they cause the development, activation, and proliferation of immune system cels Some examples include Interleukin 1 and II

Cell-Mediated Immunity 3LOD Acquired Immunity

-involves cytotoxic T Cell response to an antigen (a cellular response) - most effective against: intracellular infections, such as viral infected cells *THE PATHOGEN IS IN A CELL

What are the parts of the lymphatic tissue?

-thymus -bone marrow -lymph nodes -spleen -tonsils, adenoids

What happens if the immune response is not controlled?

If the immune response is not controlled, the potent chemicals released can harm body tissue.

How many classes of Ab are there?

IgG

What is the most abundant circulating Ab?

IgG

Why are neutrophils used in Phagocytosis in 2LOD?

types of phagocytic WBC that possess many lysosomes

The T helper cell sends out chemicals to the B cell that will bind to other receptors on the B cell CM. This further activates the B cell and allows it to ?

undergo Clonal Selection.

Antibodies (Abs) are also called?

Immunoglobulins (Igs)

What helps to generate so many different Abs?

In order to generate so many different antibodies, each with different antigen binding sites, there is DNA rearrangement of a limited number of AB gene segments that code for the H and L chains.

What is the importance of histamine dilating the vessel and increasing BV permeability in 2LOD inflamm response?

Increases circulation in that area so that WBCs and fluid escape from blood

Basophils and Eosinophil are all used for?

used for larger pns arasitic infectio

epinephrine

used in severe cases - counters the inflammatory response ex. constructs BV and BP rises

General Idea of 2nd Line of Defense

Innate phagocytes including MO and Dendritic Cells; as well as neutrophils help to : -inflammation -interferons & cytokines other chemicals -fever

What are interferons?

Interferons cannot kill pathogens themselves but just signal for an issue to be fixed

What is acquired immunity?

Involves the immune system acting against specific antigens. This is known as the immune response

What does the CD8 of Tc cells do?

It binds to the side of the MHC 1 molecule and helps to stabilize the Tc cell/infected cell interaction

B cells with antibodies that bind to self-antigen are destroyed when?

usually destroyed during their maturation in the bone marrow before they move into blood and lymph

Where does lymph fluid circulate?

Lymph fluid circulates in lymph vessels and passes through lymph nodes in groin, neck, armpit, and abdomen

What does lymph fluid contain?

Lymph fluid contains lymphocytes, macrophages, and other WBCs

What is lymph fluid similar to ?

Lymph fluid is similar to tissue fluid and blood plasma

Lymphatic fluid moves throughout the lymph system by the aid of ?

Lymphatic fluid moves throughout the lymph system by the aid of skeletal muscle contraction and one-way valves similar to the flow of blood in veins

What is the role of Tc cells in transplant rejection?

MHC 1 and 2 molecules are very polymorphic, and it is unlikely that two individuals will match at all at their MHC loci. Tc recognize foreign MHC 1 on the transplanted tissue and destroys the transplant. This is because Tc are trained to recognize and destroy viral infected cells with MHC 1 complexed to antigen. Therefore, when they see a foreign MHC 1, it may resemble a self MHC 1 bound to antigen and they are activated to release perforin causing cell lysis.

What are MHC 1 and MHC 2

MHC 1 and MHC 2 are receptors that play an important role in the immune response

Where can MHC 1 be found?

MHC 1 can be found on all nucleated body cells

What does MHC 1 help do?

MHC 1 helps present antigens to cytotoxic T (Tc) cells

What does MHC 2 helps do?

MHC 2 helps present antigens to T Helper cells

Where can MHC2 be found?

MHC II can be found on Antigen Presenting Cells (APCs) such as macrophages, dendritic cells and B cells

What can bind the constant region of Abs?

MO and neutrophils have receptors that can bind to the constant region of the Ab.

An MO once met with an antigen will secrete?

MO secretes IL-1 that helps stimulate Th cells

Why does an MO secrete IL-1 after meeting an antigen?

MO secretes IL-1 that helps stimulate Th cells

MO/neutrophils-Ab-microbe interaction make it easier for what?

MO/neutrophils-Ab-microbe interaction make it easier for the WBC to engulf the microbe

What makes it easier for the WBC to engulf the microbe?

MO/neutrophils-Ab-microbe interaction make it easier for the WBC to engulf the microbe

How many antibodies can bind to 1 antigen?

Many antibodies can attach to 1 antigen because 1 antigen has many epitopes.

Many of the unpleasant symptoms of an infection (ex. Fever, aches, etc. ) are actually caused by?

Many of the unpleasant symptoms of an infection (ex. Fever, aches, etc. ) are actually caused by the immune system chemicals trying to eliminate the infection, not by the microbes themselves

Many of the cloned activated cells that can interact with the same antigen will remain in the body for ?

Many of these will remain in the body for long periods of time as memory cells.

Each H and L chain has a ?

variable and a constant region

What determines which epitope Ab will bind to

variable region of H and L chains

When can Memory cells can be activated?

Memory cells can be activated the next time you encounter the same antigen, and since you will have thousands of these your response is much quicker and more potent.

Why don't you get sick when infected by the same microbe a second time?

Memory cells can be activated the next time you encounter the same antigen, and since you will have thousands of these your response is much quicker and more potent.

At the same time as the secondary response B cell clones, what happens to the rest of the MO and Th?

More interferons so that more memory cells are produced

Innate Immunity of Prokaryotes

Most bacteria employ restriction enzymes which cut viral or otherwise non-self DNA to render it unable to be transcribed and translated into new viral protein, plasmid or other nucleic acid such as extra chromosomal DNA. more than 400 restriction enzymes have been isolated from the bacteria that manufacture them. In live bacteria restriction enzymes function to defend the cell against invading viral bacteriophages. restriction sites in the viral genome or happy accident of nature as far as the bacteria or concerns in Sedona. To have any specific function the virus is clean to the bacterium's restriction enzymes, fragmenting and destroying the DNA of invading bacteriophages before I can incorporate into the host's genome and take over the cell. The bacteria is immune to its own restriction enzymes even if it has a Target sequence ordinarily targeted by them; this is because the bacterial restriction sites are highly methylated, making them unrecognizable to the Restriction enzyme.

Does the receptor shape change in response to a particular antigen?

No! The receptor shape is predetermined during the development of a B cell. It is NOT produced in response to a particular antigen

Leukocytes (WBCs) differentiate into?

Non-lymphocytes or granulocytes Lymphocytes or agranulocytes

What is built during passive immunity?

Not memory cells

The Constant Heavy chains determine?

what type of antibody you are dealing with

What B cell will be able to bind to the specific Ag on the invading microbe?

Only the B cell(s) with the specific receptor will be able to bind to the specific Ag (epitope) on the invading microbe

What B cell will be activated?

Only the B cell(s) with the specific receptor will be able to bind to the specific Ag (epitope) on the invading microbe will be activated and divide to form clones

Neutrophils, Macrophages, and Dendritic Cells are all what kind of WBCs?

Phagocytic Cells

Plasma cells secrete antibodies with the same antigen-binding region as

Plasma cells secrete antibodies with the same antigen-binding region as the ones that were in the CM of the activated B cell.

What do plasma cells do ?

Plasma cells secrete antibodies with the same antigen-binding region as the ones that were in the CM of the activated B cell.

Where do Pre-B cells mature?

Pre-B become mature into B cells in the bone marrow.

What happens in the thymus?

Pre-T cells mature and those that have receptors that bind to self-antigens are destroyed

Compare and contrast the primary and secondary immune response

Primary: - first response to Ag -slower to start - produces memory B cells; makes host immune to a second infection with the same antigen Secondary: - second response to same Ag - faster and more potent - produces memory again

How does clonal selection occur for Th cells?

Proliferation of the T cell, stimulated by cytokines from both the dendritic cell and T cell itself, gives rise to a clone of activated helper T cells all with receptors for the same MHC-antigen complex

When do you notice symptoms for the first time in immunity?

Second line of defense. Fev/achey pain - need this to kick start cells

In cell mediated immunity, a specific cytotoxic T cell binds to a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a target cell via its TCR with the aid of?

with the aid of CD8.

What gives rise to all blood cells?

Stem cells in bone marrow give rise to all blood cells

What happens in bone with marrow in lymph system?

Stem cells will form Pre-T and B cells. T cells are dumped as Pre-T's into the blood and they travel to the thymus. Pre-B become mature into B cells in the bone marrow. If a B cell is formed that binds to a self antigen, it is destroyed

What do lymphocytes differentiate into?

T Cells - T Helper Cells (Tn) - Cytotoxic T Cells (Tc) - Suppressor T Cells - NKT Cells - "Natural Killer" B Cells - plasma cells - spit out antibodies

The Ag/MHC 1 binding, in addition to the IL-2 that is secreted by the ?

T Helper Cell

The thymus is the site of blank cell maturation

T cell maturation

How are T cells found in blood?

T cells are dumped as Pre-T's into the blood and they travel to the thymus

What complex is created first with the Th cells on MO?

TCR to the Ag-MHC II complex on the MO

Where is the pathogen in cell-mediated immunity?

THE PATHOGEN IS IN A CELL

Where is the pathogen in humoral immunity?

THE PATHOGEN IS IN BLOOD OR TISSUE FLUID

How many days does the first response take to produce efficient levels of antibodies with B cells?

Takes 7-10 days to produce efficient levels of antibodies - abt a week

Tc recognizes foreign MHC 1 on the transplanted tissue and destroys the transplant because

Tc are trained to recognize and destroy viral infected cells with MHC 1 complexed to antigen. Therefore, when they see a foreign MHC 1, it may resemble a self MHC 1 bound to antigen and they are activated to release perforin causing cell lysis.

After maturing, where does the B cell go?

The B cell moves into the general blood/lymph circulation

What B cell will be cloned?

The B cell that has antibodies that match the antigen

What happens to the IL-2 that the T helper cell secretes?

The IL-2 that the T helper cell secretes also binds to membrane receptors on cytotoxic T cells (Tc cells) and helps to activate them.

The T helper Cell Receptor (TCR) binds Ag-MHC II complex on the?

The T helper Cell Receptor (TCR) binds Ag-MHC II complex on the MO

After Th cells are stimulated, the T Helper Cell Receptor (TCR) binds ?

The T helper Cell Receptor (TCR) binds Ag-MHC II complex on the MO, and its CD4 receptor also binds to the side of the MHC II molecule, helping to stabilize the T helper cell/macrophage interaction.

After Th cells are stimulated, what binds the Ag-MHC II complex on the MO, and its CD4 receptor also binds to the side of the MHC II molecule, helping to stabilize the T helper cell/macrophage interaction?

The T helper Cell Receptor (TCR) binds Ag-MHC II complex on the MO, and its CD4 receptor also binds to the side of the MHC II molecule, helping to stabilize the T helper cell/macrophage interaction.

How does the B cell get further activated after the Ag-MHC II complex is created with the TCR and the CD4 stabilization?

The T helper cell sends out chemicals to the B cell that will bind to other receptors on the B cell CM. This further activates the B cell and allows it to undergo Clonal Selection.

What kind of receptor does Tc cell have?

The Tc cell has a CD8 receptor that is similar to the T Helper Cells CH4 receptor.

What happens to an activated B cell?

The activated B cell proliferates and differentiates into memory B cells and antibody-secreting plasma cells. The secreted antibodies are specific for the same bacterial antigen that initiated the response

The activated T cell releases what molecules in cell mediated immunity?

The activated T cell releases perforin molecules, which form pores in the target cell membrane, and proteolytic enzymes (granzymes), which enter the target cell by endocytosis

Antibodies connect to what part of antigens?

The antigen-binding sites of antigens

What determines class of Ab?

The constant region of H chain only

What effect does perforin have in cell mediated immunity?

The cytotoxic T cell secretes a chemical called perforin that destroys the infected cell by causing cell lysis.

What is secreted by a cytotoxic T cell or Tc cell?

The cytotoxic T cell secretes a chemical called perforin that destroys the infected cell by causing cell lysis.

the immune response involves BLANK and BLANK?

The immune response involves humoral identity and cell-mediated immunity

What does the interaction between the MO and the T helper cell cause?

The interaction between the MO and the T helper cell causes a signal transduction pathway that leads to the T helper cell production of IL2 and other immune chemicals that activate a variety of immune cells.

The interaction between the antigen and WBCs activates?

The interaction between the antigen and WBCs activates the cells and initiates what is known as the immune response

What does the main receptor of the cytotoxic T cell do?

The main receptor of the cytotoxic T cell recognizes and binds to the Ag/MHC I receptor

After MHC II receptor on B APC cell binds to antigen with their antigen receptor and takes in the microbe by endocytosis, what happens to the microbe?

The microbe is then broken down and a piece of it is displayed in an MHC 2 molecule, similar to what occurs in a macrophage.

Why does the primary response take more time?

The primary response takes more time bc the Ag must encounter IS cells, and then produce clones, etc. The secondary response is much faster because there are many memory cells produced from the primary response that are ready to interact with Ag.

The DNA rearrangement is ordered or random for Abs?

The rearrangements are random, so sometimes antibodies are produced that will bind to self antigens

The receptor shape is predetermined during?

The receptor shape is predetermined during the development of a B cell. It is NOT produced in response to a particular antigen

What are antigenic determinants or epitomes ?

The regions the antibodies and immune cells recognize and bind to

How are the 4 polypeptide chains of antibodies structures?

There are 2 heavy chains (longer H) and 2 lighter chains (shorter L)

Are Ab genes separated?

There are NOT separate genes coding for all the possible antibody proteins ( there are millions of different antibodies and only about thirty thousand or so total genes in the human genome).

How many B Cells are there in the body?

There are millions of B cells, each with its own specific B cell receptor, in the body at a given time

These MHC variable proteins act as?

These MHC variable proteins act as foreign antigens in organ and tissue transplants

Where do antibodies end up?

These antibodies can end up in almost all body fluids such as tissue fluid, saliva, mucus membranes, blood and lymph.

Lymph fluid contains lymphocytes, macrophages, and other WBCs. What do these cells do?

These cells meet and communicate in the lymph nodes and other lymphatic tissue, such as the spleen and tonsils.

How do secreted antibodies travel?

These secreted antibodies will travel throughout the body, bind to the microbes, and help to destroy them. This part of the immune response is called Humoral Immunity.

MHC II receptors on B APC Cells can bind to ?

They can bind to an antigen on the microbe with their antibody receptor and then take in the microbe by endocytosis

After stem cells differentiate into Pre-B cells, they remain in the bone marrow and and complete their maturation process. What will they become?

They will become a specific type of B cell that is able to recognize a particular foreign antigen.

After stem cells differentiate into Pre-T Cells they move out of bone marrow and into thymus gland, and complete their maturation process. What will they become?

They will become a specific type of T cell with a specific T cell receptor that is able to recognize a particular foreign antigen

They will become a specific type of T cell with a specific T cell receptor that is able to?

They will become a specific type of T cell with a specific T cell receptor that is able to recognize a particular foreign antigen

What is the importance of MHC 1 and II being coded for by polygenic genes that have multiple alleles?

This allows each individual to have many different MHC molecules on the surface of their cells

The Ag/MHC 1 binding, in addition to the IL-2 that is secreted by the T Helper Cell has what effect?

This binding, in addition to the IL-2 that is secreted by the helper T cell, activates, and causes Clonal Selection of Tc cells.

What happens after IL-2 is released from T helper cells and then binds to receptors on the surface of the T helper cell?

This causes another signal transduction pathway that eventually causes the T cell to become stimulated to undergo clonal selection.

The CRISPR gene contains a leader sequence followed by a number of sequences that have short repeated segments that are separated by gaps that contain viral DNA. This forms?

This forms a locus that contains the memory of previous infections that the bacterium suffered from.

The TCR binding to the displayed complex via its TCR with the aid of CD4 interaction promotes what?

This interaction promotes secretion of cytokines by the dendritic cell

Whether a T cell will be a T Helper cell or a Cytotoxic T cell must also be determined during its maturation process. This is dependent upon?

This is dependent upon chemical stimulation from other cells

Memory cells can be activated the next time you encounter the same antigen, and since you will have thousands of these your response is much quicker and more potent. This is why?

This is why you usually don't get sick when infected by the same microbe a second time.

When does DNA rearrangement for Abs occur?

This rearrangement occurs during the development of a particular B cell BEFORE the B cell encounters Ag.

Complement proteins bind to antibodies that are already attached to the surface of the microbe. This triggers?

This triggers a Cascade of events that ultimately leads to some of these complement proteins embedding themselves into the membrane of the microbe. the embedded proteins from a pore, which caused cell lysis.

What is an example of an autoimmune disease

Type 1 diabetes caused when immune cells kill a person's pancreatic beta cells that form insulin Others like Autoimmune Arthritis, Crohn's Disease, Lupus

Unlike other receptors discussed, MHC 1 and MHC 2 receptors are what in relation to antigen specificity?

Unlike other receptors discussed, MHC 1 and MHC 2 receptors are gensnot specific for specific anti

How does clonal selection work for B cells? What do they differentiate into?

When they clone, some of the B cells differentiate into plasma cells, and many remain as memory B cells.

Whether a T cell will be a BLANK or BLANK must also be determined during its maturation process

Whether a T cell will be a T Helper cell or a Cytotoxic T cell must also be determined during its maturation process

Whether a T cell will be a T Helper cell or a Cytotoxic T cell must also be determined during its?

Whether a T cell will be a T Helper cell or a Cytotoxic T cell must also be determined during its maturation process

The CRISPR gene contains a

a leader sequence

After MHC II receptor on B APC cell binds to antigen with their antigen receptor and takes in the microbe by endocytosis, the microbe is then broken down and where is it displayed?

a piece of it is displayed in an MHC II molecule, similar to what occurs in a macrophage.

An interferon in 2LOD inflamm response is ?

a protein that is active against viral infection

In cell mediated immunity, a specific cytotoxic T cell binds to a?

a specific cytotoxic T cell binds to a class MHC 1-antigen complex

In cell mediated immunity, a specific cytotoxic T cell binds to a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a ?

a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a target cell

In cell mediated immunity, a specific cytotoxic T cell binds to a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a target cell via ?

a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a target cell via its TCR

What leads to the activation of the Tc cell?

a specific cytotoxic T cell binds to a class MHC 1-antigen complex on a target cell via its TCR with the aid of CD8. This interaction, along with cytokines from helper T cells, leads to the activation of the cytotoxic cell

Anaphylaxis

a type of shock caused by severe inflammatory response where excessive amounts of histamine, prostaglandins, and other potent chemicals are produced

What is known as the immune response?

acquired immunity

General Idea of 3rd Line of Defense

acquired immunity -Humoral - bacterial/viruses -Cell Mediated - signal from an infected cell (virus/cancer) - (Th) T-helper cells - Tc Cytotoxic T Cells - B Cells - Plasma Cells - Antibodies

The interaction between the MO and the T helper cell causes a signal transduction pathway that leads to the T helper cell production of IL2 and other immune chemicals that ?

activate a variety of immune cells.

Only what kind of cells divide by mitosis in clonal selection?

activated cells

What are the two types of immunities?

active and passive

All vertebrates have immune systems that involve both?

adaptive and innate immunity

Stem cells in bone marrow give rise to?

all blood cells

Disorders of the Immune System

allergies, AIDS

MO/APCs engulfs microbe, digests it, and displays part of it on its surface bound to ?

an MHC II receptor

After stem cells differentiate into Pre-B cells, they remain in the bone marrow and do what?

and complete their maturation process

Humoral Immunity is most effective against free bacteria and other antigens in body fluids where?

antibodies circulate

A specific B cell receptor encountering its complementary antigen is a chance event that occurs as the ?

as the B cell and antigen circulate within the lymphatic or circulatory system

Most of the time, the body produces antibodies as what happens?

as they encounter antigens

What gives off nitrous oxide when they encounter microbes in 1LOD?

bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes

bitter taste receptors in mouth and other organs give off BLANK when they encounter microbes in 1LOD?

bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes

Both interferons and memory B cells do what?

both add to the overall health of the immune system

Innate phagocytes including MO and Dendritic Cells do what between 2/3rd lines of defense?

bridge the gap to 3rd line of defense by

The released cytotoxic T cell can do what?

can attack other target cells

What is a limitation of role of Tc cell in destroying cancer cells?

can only do this if a weird protein is present on MHC receptor. otherwise cancer not detected

Complement Proteins main function

cause lysis of an invading microbe

Unlike animal's system wide response, plants have?

cell by cell response

MHC 1 is involved in what kind of 3LOD immunity?

cell mediated

What immunity is a cellular response?

cell-mediated immunity

A specific B cell receptor encountering its complementary antigen is what kind of event?

chance event

Asthma

chronic type of allergic/inflamm response. not understood why but might bc they're more sensitive to the chem released during this reactions or that they have more of these chemicals present

In order to generate so many different antibodies, each with different antigen binding sites, there is DNA rearrangement of a limited number of AB gene segments that code for

code for the H and L chains.

antihistamine

competes with histamine for receptors on cells (blocks histamine binding)

Scientists are harnessing CRISPR Cas 9 to bind to

complete DNA and cut out and eventually insert novel DNA into the genome of organisms. This is a new way to create transgenic organisms.

crRNA acts as

crRNA acts as siRNA or small interference DNA by binding to complementary viral DNA.

What is pus made of?

dead WBCs, dead bacteria, dead cells

Why is there pus in 2LOD inflamm response?

dead WBCs, dead bacteria, dead cells

What is the function of the Inflammatory Response (as in a wound response) in 2LOD?

designed to destroy or wall off injured or infected area

The constant region of H chain only determines?

determines its function, or what the antibody can do once it has bound to the antigen

An antibody consists of 4 polypeptide chains bonded together by ?

disulfide bonds

Only the B cell(s) with the specific receptor will be able to bind to the specific Ag (epitope) on the invading microbe will be activated and ?

divide to form clones

MHC II receptors on B APC Cells can bind to an antigen on the microbe with their antibody receptor and then take in the microbe by ?

endocytosis

What helps in phagocytosis in 2LOD?

engulfing of microbes/antigens by macrophages (MO) and neutrophils (types of phagocytic WBC that possess many lysosomes)

What is phagocytosis in 2LOD?

engulfing of microbes/antigens by macrophages (MO) and neutrophils (types of phagocytic WBC that possess many lysosomes)

How does granzymes or proteolytic enzymes enter the target cell?

enter the target cell by endocytosis

What enzyme is involved in the chemical barriers in 1LOD?

enzyme (lysozyme)

pathogen associated molecular patterns are analogous to?

epitopes/Ag

Why is there swelling in 2LOD inflamm response?

fluid and WBCs

Tc recognizes?

foreign MHC 1

What do the perforin molecules do in cell mediated immunity?

form pores in the target cell membrane

The variable region of H and L chains forms?

forms 2 identical antigen binding sites

The granzymes initiate apoptosis within the target cells, leading to?

fragmentation of the nucleus, release of small apoptotic bodies, and eventual cell death.

Why is innate immunity nonspecific defense?

function against all antigens - first or second LOD

What gives off interferons ?

given off by viral infected cells

Lymph fluid circulates in lymph vessels and passes through lymph nodes in?

groin, neck, armpit, and abdomen

What are clones

group of genetically identical cells descended from a common ancestral cell

The immune system often reacts to harmless foreign substances the same as it does to ?

harmful foreign substances

Prokaryotic Immunity

have both innate and adaptive immunity

Plant immunity

have the ability to respond to PAMPs or Pathogen ASsociated Molecular Patterns such as peptidoglycans and flagellin on the outside of bacteria, LPS like those on gram negative bacteria, double stranded RNA dsRNA from viruses, mannan polysaccharides and chitin in the cell wall of yeast. This is not a system wide response as in animals but a cell by cell response. Pattern recognition receptors (PRR's) bind to the PAMP's and a signal transduction causes production of cytokines, phagocytosis, production of defensin proteins, and complement proteins.

Why is there a CD4 receptor also binding to the side of the MHC II molecule alongside the TCR and Ag-MHC II complex on the MO?

helps to stabilize the T helper cell/macrophage interaction.

MHC 2 is involved in what kind of 3LOD immunity?

humoral

Humoral Immunity 3LOD Acquired Immunity

humoral means fluids - involves the B cell response to Ag (the production of antibody molecules to recognize the epitopes of antigens) - most effective against free bacteria and other antigens in body fluids where antibodies circulate *THE PATHOGEN IS IN BLOOD OR TISSUE FLUID

Clonal selection is when only the activated cells will clone (divide by mitosis) many times to produce?

identical cells that can interact with the same antigen.

What happens if a T or B cell slips past the maturation process in the Thymus and has a receptor that can bind to a self antigen?

if a T or B cell slips past the maturation process in the Thymus and has a receptor that can bind to a self antigen, the person may end up with an autoimmune disease

The B cells that have these antibodies are usually destroyed during their maturation in the bone marrow before they move into blood and lymph. if one escapes destruction, it could lead to?

if one escapes destruction and may lead to an autoimmune disease where the antibodies attack one's own tissues.

Active immunity involves the production of?

immune response

What is an allergy ?

immune response to allergens (Ags that case allergy like pollen)

Autoimmune Disease

immune system (Abs or Tc cells) attacks self antigens

After MHC II receptor on B APC cell binds to antigen with their antigen receptor and takes in the microbe by endocytosis, the microbe is then broken down and a piece of it is displayed in an MHC II molecule, similar to what occurs where?

in a macrophage.

If a cell is infected with a virus or other intracellular parasite, the infected cell will display a piece of the microbe in what receptor?

in an MHC 1 receptor

Where is enzyme (lysozyme) found in 1LOD?

in tears, saliva, and sweat; breaks down bacteria cell walls; stomach acid ex. bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes

Due to mutations, cancer cells will produce proteins that are not found in normal cells. Parts of these proteins can wind up in the ?

in the MHC 1 receptors on the cell surfaces

The lymphatic system is important in the function of what cells?

in the function of B and T Cells

Why is there redness/heat in 2LOD inflamm response?

increasd circulation

Removal of tonsils, adenoids does what?

increases change of autoimmune disorder like Crohn's

How does a fever affect cell metabolism?

increases our cell metabolism bc chemical reactions are increasing

What is the primary response?

initial encounter with antigen

What do the proteolytic enzyme (granzymes) molecules do in cell mediated immunity?

initiate apoptosis within the target cells, leading to fragmentation of the nucleus, release of small apoptotic bodies, and eventual cell death

All vertebrates have immune systems that involve both adaptive and innate immunity. Other organisms exhibit only?

innate immunity

Once mature, the T cell moves into the ?

into the general blood/lymph circulation where it will encounter antigen

cell-mediated immunity is most effective against?

intracellular infections, such as viral infected cells

What cell does cell-mediated immunity involve?

involves cytotoxic T Cell response to an antigen (a cellular response)

What cell response does Humoral immunity involve?

involves the B cell response to Ag

Stem cells in bone marrow give rise to all blood cells. The differentiation and development of these cells is influenced by?

is influenced by chemicals which are released from various cells of the body, depending on what the body needs at the time

What happens after a macrophage engulfs and degrades a bacterium?

it displays a peptide antigen complexed with a class MHC II molecule.

What happens after a dendritic cell engulfs and degrades a bacterium?

it displays bacterial antigen fragments (peptides) complexed with MHC II molecules on the cell's surface

Tc recognizes foreign MHC 1 on the transplanted tissue and destroys the transplant. This is because Tc are trained to recognize and destroy viral infected cells with MHC 1 complexed to antigen. Therefore, when they see a foreign MHC 1

it may resemble a self MHC 1 bound to antigen and they are activated to release perforin causing cell lysis.

What happens as the T helper Cell Receptor (TCR) binds Ag-MHC II complex on the MO?

its CD4 receptor also binds to the side of the MHC II molecule, helping to stabilize the T helper cell/macrophage interaction.

The interaction between the MO and the T helper cell causes a signal transduction pathway that leads to?

leads to the T helper cell production of IL2 and other immune chemicals that activate a variety of immune cells.

What is the inflammatory response or wound response

local protective response to tissue injury or infection

How long does active immunity last for?

long-lasting

In humoral immunity, what engulfs and degrades a bacterium first?

macrophage

What are Antigen Presenting Cells (APCs)?

macrophages, dendritic cells and B cells

What does MHC stand for?

major histocompatibility complex

The primary immune responses makes the host what?

makes host immune to a second infection with the same antigen

As with helper T cells and B cells, many of the cloned Tc cells will remain as

many of the cloned Tc cells will remain as memory cells.

After stem cells differentiate into Pre-T Cells they move out of bone marrow and into thymus gland, and complete their ??

maturation process

Many of cloned activated cells will remain in the body for long periods of time as ?

memory cells

What does active immunity build?

memory cells

Many of the unpleasant symptoms of an infection (ex. Fever, aches, etc. ) are actually caused by the immune system chemicals trying to eliminate the infection, not by the microbes themselves. Some symptoms, of course, are caused by the

microbes

Other than histamine, why are other chemicals released from injured cells in 2LOD inflamm response?

microbes attract WBCs to area - WBCs can then phagocytize and digest the microbes

Humoral Immunity is most effective against?

most effective against free bacteria and other antigens in body fluids where antibodies circulate

The interaction between the MO and the T helper cell causes a signal transduction pathway that leads to the T helper cell production of what?

of IL2 and other immune chemicals that activate a variety of immune cells.

In order to generate so many different antibodies, each with different antigen binding sites, there is DNA rearrangement of

of a limited number of AB gene segments that code for the H and L chains.

The IL-2 that the T helper cell secretes also binds to membrane receptors on

on cytotoxic T cells (Tc cells) and helps to activate them.

MO/APCs engulfs microbe, digests it, and displays part of it where?

on its surface bound to an MHC II receptor

The constant regions are the same from?

one antibody to the next

PAMPs stands for

pathogen associated molecular patterns

General Idea of 1st Line of Defense

physical and chemical innate barriers that were built in genetically

There is usually what kind of response in B and antigen interaction?

polyclonal response, meaning that more than 1 type of B cell will respond to one microbe because the microbe has more than one epitope

What is the importance of blood clot formation in 2LOD inflamm response?

prevents hemorrhage

Why do plants produce cytokines?

produce proteins to help protect them

Allergies are important in ?

protecting in wound healing and involved in inflammatory response

IL-2 is released from T helper cells and then binds to receptors on?

receptors on the surface of the T helper cell.

Tc are trained to recognize and destroy viral infected cells with MHC 1 complexed to antigen. Therefore, when they see a foreign MHC 1, it may resemble a self MHC 1 bound to antigen and they are activated to ?

release perforin causing cell lysis.

Where is histamine released from in inflammatory response in 2LOD?

released from injured cells

From what is an interferon released from in 2LOD inflamm response?

released from virus infected cells and stimulates surrounding cells to resist the viral infection (interferon doesn't kill the virus

Invertebrates like Octopus

response to infection is to increase expression of proteins that protect the octopus. these include complement proteins that function to help destroy the pathogen

The second binding of an allergen with original epitope causes?

response where lots of histamine produced by exocyotsis

Once the antigen meets a macrophage or another Antigen Presenting Cell (APC) like a Dendritic Cell, it does what?

1. Engulfs microbe, digests it, and displays part of it on its surface bound to an MHC II receptor 2. MO secretes IL-1 that helps stimulate Th cells

Why is acquired immunity specific defense?

responses against a SPECIFIC antigen. final 3rd line of defense

Which is more potent the primary or secondary immune response?

secondary immune responses

The first binding of IgE antibodies has what effect?

sensitizes mast cells

Anaphylaxis could be due to?

severe allergic reactions like bee stings and certain food allergies

What does the Inflammatory Response (as in a wound response) involve in 2LOD?

1. histamine - released from injured cells - dilates vessel and increases blood vessel permeability so that the WBCs and fluid escape from blood - increases circulation in the area 2. other chemicals released from injured cells and microbes attract WBCs to area - WBCs can then phagocytize and digest the microbes 3. Blood clot formation - prevents hemorrhage

How many memory cells are produced by B cells?

1000s

The CRISPR gene contains a leader sequence followed by a number of sequences that have

short repeated segments that are separated by gaps that contain viral DNA.

During the first exposure to an allergen, there is the first binding between what kind of cells?

1st binding of T/B cells and appropriate IL --> IgE antibodies

agglutination occurs because Abs have

2 Ag binding sites ex. agglutinates bacterial cells which clumps them together allowing easier phagocytosis

How long does passive immunity last for?

short-lived

An antibody is a protein consisting of how many polypeptide chains?

4 polypeptide chains bonded together by disulfide bonds

Just like histamine, there is a class of chemicals called prostaglandins that cause ?

similar and often more severe symptoms. these chemicals are also released from mast cells during an allergic or inflammatory response

How does the macrophage and B cell relate in humoral identity

A B cell that has taken up and degraded the same bacterium as the macrophage that formed an Ag-MHC II interaction with TCR with CD4 stabilization

A B cell that has taken up and degraded the same bacterium displays what on its surface?

A B cell that has taken up and degraded the same bacterium displays class MHC II-peptide antigen complexes.

What happens after the microbe is broken down by the B APC cell and a piece of it is displayed in a MHC II molecule?

A T helper cell with the correct T cell receptor will bind to the Ag-MHC II complex on a B cell, and its CD4 receptor also binds to the MHC II molecule, helping to stabilize the T helper Cell/B cell interaction

Once a macrophage engulfs and degrades a bacterium, it displays a peptide antigen complexed with a class MHC II molecule. Then a helper T cell will recognize the displayed complex and activates with the help of ?

A helper T cell that recognizes the displayed complex is activated with the aid of cytokines secreted from the macrophage, forming a clone of activated Th cells.

A response to produce antibodies against an antigen is considered?

A response to produce antibodies against an antigen is considered polyclonal - many clones

A single antigen usually has ?

A single antigen usually has many antigenic determinants or epitomes

after a dendritic cell engulfs and degrades a bacterium, it displays bacterial antigen fragments (peptides) complexed with MHC II molecules on the cell's surface. how does a specific Th cell come into play?

A specific helper T cell binds to the displayed complex via its TCR with the aid of CD4.

What are the physical barriers in the first line of defense?

skin, mucus membranes (throat and alimentary canal), cilia, hair - bacteria, cuticles, dead skin

Th is activated by what kind of cell?

APC LIKE A DENDRITIC CELL

What are self antigens?

small molecules on your own cells that could elicit an immune response - they are built incorrectly nd bind to self - autoimmune disorder

After stem cells differentiate into Pre-B cells, they remain in the BLANK

After stem cells differentiate into Pre-B cells, they remain in the bone marrow

After stem cells differentiate into Pre-T Cells they move out of BLANK and into BLANK

After stem cells differentiate into Pre-T Cells they move out of bone marrow and into thymus gland

Antibodies are composed on what molecular basis?

Ag are usually proteins but can be polysaccharides

The main receptor of the cytotoxic T cell recognizes and binds to

Ag/MHC I receptor

What happens once there are MHC 2-peptide antigen complexes on the surface of a B cell?

An activated helper T cell bearing receptors for the displayed antigen binds to the B cell. This interaction with the aid of cytokines from the T cell, activates the B cell

What is an Antibody (Ab)?

An antibody is a Y-shaped protein with identical sites that bind to specific antigens. Antibodies are produced by B lymphocytes

Bacteria contain endotoxins contain exotoxins

some bacteria contain endotoxins, which are the LPS (lipopolysaccharides) that make up the other membrane of Gram-negative bacteria. Bacteria also secrete exotoxins, such as the toxins that cause botulism or tetanus

immunodeficiency

some people are born w defects in the IS and are susceptible to infection ex. SCID - boy in the bubble caused by lack of an enzyme called adenosine deaminase that inhibits development of IS AIDS = Acquired Immune Deficiency Syndrome caused by HIV Retrovirus

Invertebrates like Ants

Animals can also respond to PAMPs. Pathogens such as fungi elicit expression of proteins involved n innate immunity. Ants in a colony have been known to feed off nest mates that are infected with fungus by licking a small amount of fungus off of the infected nest-mate. This improves the immunity of the colony because it elicits expression of proteins that will kill the fungus - almost like a self vaccination

In the beginning of the immune response, where does the antigen go once inside the body?

Antigen gets into body, circulates in blood and lymph

After the antigen gets into body and circulates in blood and lymph, what does it meet?

Antigen gets into body, circulates in blood and lymph, and eventually meets with macrophages and other immune cells in some lymph tissue such as a lymph node

Describe the complete immune response

Antigen gets into body, circulates in blood and lymph, and eventually meets with macrophages and other immune cells in some lymph tissue such as a lymph node Macrophage (MO) or another Antigen Presenting Cell (APC) like a Dendritic Cell Engulfs microbe, digests it, and displays part of it on its surface bound to an MHC II receptor MO secretes IL-1 that helps stimulate Th cells The T helper Cell Receptor (TCR) binds Ag-MHC II complex on the MO, and its CD4 receptor also binds to the side of the MHC II molecule, helping to stabilize the T helper cell/macrophage interaction. The interaction between the MO and the T helper cell causes a signal transduction pathway that leads to the T helper cell production IL2 and other immune chemicals that activate a variety of immune cells. IL-2 is released from T helper cells and then binds to receptors on the surface of the T helper cell. This causes another signal transduction pathway that eventually causes the T cell to become stimulated to undergo clonal selection. Cloncal selection is when only the activated cells will clone (divide by mitosis) many times to produce identical cells that can interact with the same antigen. Many of these will remain in the body for long periods of time as memory cells. Memory cells can be activated the next time you encounter the same antigen, and since you will have thousands of these your response is much quicker and more potent. This is why you usually don't get sick when infected by the same microbe a second time. B cells are also antigen presenting cells that have MHC II receptors in their CM. They can bind to an antigen on the microbe with their antibody receptor and then take in the microbe by endocytosis. The microbe is then broken down and a piece of it is displayed in an MHC 2 molecule, similar to what occurs in a macrophage. A T helper cell with the correct T cell receptor will bind to the Ag-MHC II complex on a B cell, and its CD4 receptor also binds to the MHC II molecule, helping to stabilize the T helper Cell/B cell interaction The T helper cell sends out chemicals to the B cell that will bind to other receptors on the B cell CM. This further activates the B cell and allows it to undergo Clonal Selection. When they clone, soe of the B cells differentiate into plasma cells, and many remain as memory B cells. Plasma cells secrete antibodies with the same antigen-binding region as the pens that were in the CM of the activated B cell. These antibodies can wind up in almost all body fluids such as tissue fluid, saliva, mucus membranes, blood and lymph. These secreted antibodies will travel throughout the body, bind to the microbes, and help to destroy them. This part of the immune response is called Humoral Immunity. *If the immune response is not controlled, the potent chemicals released can harm body tissue. Many of the unpleasant symptoms of an infection (ex. Fever, aches, etc. ) are actually caused by the immune system chemicals trying to eliminate the infection, not by the microbes themselves. Some symptoms, of course, are caused by the microbes. For example, some bacteria contain endotoxins, which are the LPS (lipopolysaccharides) that make up the other membrane of Gram-negative bacteria. Bacteria also secrete exotoxins, such as the toxins that cause botulism or tetanus The IL-2 that the T helper cell secretes also binds to membrane receptors on cytotoxic T cells (Tc cells) and helps to activate them. If a cell is infected with a virus or other intracellular parasite, the infected cell will display a piece of the microbe in an MHC 1 receptor. The main receptor of the cytotoxic T cell recognizes and binds to the antigen/MHC I receptor. The main receptor of the cytotoxic T cell recognizes and binds to the antigen/MHC 1 complex. This binding, in addition tot he IL-2 that is secreted by the helper T cell, activates, and causes Clonal Selection of T c cels. The Tc cell has a CD8 receptor that is similar tot he T Helper Cell's CH4 receptor. It binds to the side of the MHC 1 molecule and helps to stabilize the Tc cell/infected cell interactio. The cytotixc T cell secretes a chemical called perforin that destroys the infected cell by causing cell lysis. As with helper T cells and B cells, many of the cloned Tc cells will remain as memory cells.

How does the lymph fluid interaction flow in an infection?

Antigen in tissue fluid -> lymph vessels --> nodes and meets with immune cells

Cas9 acts to cut the viral DNA and

stop infection b4 virus inserts into the host genome

Memory B cells stay in blood stream and lymph for long periods until?

subsequent challenge by same antigen

An interferon is released from virus infected cells and stimulates ?

surrounding cells to resist the viral infection (interferon doesn't kill the virus)

Each microbe has molecular groups on its surface that?

that could act as an antigen

Cytokines are chemical signals that ?

that promote immune responses by attracting WBCs to areas of infections

What is an Antigen (Ag)?

Any substance that can produce an immune response Ex. microbe, piece of microbe, cell surface protein, pollen, etc

Why is most of your T cell production will be early in life ?

As an individual ages, the thymus shrinks considerably in size.

What are the B cells?

B Cells - plasma cells - spit out antibodies

In addition to being the site where all blood cells are produced, the bone marrow is a site of ?

B cell maturation

B Cells are what kind of cells just like Dendritic cells?

B cells are also antigen presenting cells

B cells are also antigen presenting cells that have what receptor in their CM?

B cells are also antigen presenting cells that have MHC II receptors in their CM.

Bone w Marrow = Thymus =

B cells mature T cells mature

Antibodies are produced by

B lymphocytes

What does anaphylaxis cause?

BV dilation and increased permeability and lots of plasma to be lost from blood, causing drastic drop in BP known as shock

Why must organ recipient and donor be matched at least to some extent ?

Bc of their MHC molecules similarity. If not, the recipient, then they will reject the transplant

Why is there great variation among a person's MHC molecules?

Bc these polymorphic alleles produce great variation in the population, very few people will have the same set of MHC molecules

Why is a response to produce antibodies against an antigen is considered polyclonal - many clones ?

Because more than 1 type of antibody is produced for each antigen

Both MHC 1 and II are coded for by ?

Both MHC 1 and II are coded for by a group of 20 or so polygenic genes that all have multiple alleles

Both the B cell response of humoral immunity and Cytotoxic T response of Cell-mediated immunity require?

Both the B cell response of humoral immunity and Cytotoxic T response of Cell-mediated immunity cremulation from Helper T require chemical stimulation from Helper T cells

Adaptive Immunity of Prokaryotes

CRISPR/CAs9 system found in streptococcus pyogenes (gram positive cause of strep throat and other infections) studied by Jennifer Doudna and Emannuella Charpientier at UC Berkeley. THe CRISPR system has been found in both Eubacteria and Archaea and is slightly different in each type of bacteria. CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats. The CRISPR gene contains a leader sequence followed by a number of sequences that have short repeated segments that are separated by gaps that contain viral DNA. This forms a locus that contains the memory of previous infections that the bacterium suffered from. The spacer regions that can be transcribed into crRNA can be bound to another RNA called a tracrRNA. The complex formed will bind to the Cas 9 protein. The CRISPR/Cas 9 complex can then bind to new, attacking viral genomes that are complementary to the sequences that were originally cut and inserted into the CRISPR locus. crRNA acts as siRNA or small interference DNA by binding to complementary viral DNA. Cas9 acts to cut the viral DNA and stop infection b4 virus inserts into the host genome. Bc memory of og virus is held in CRISPR locus, the bacteria can remember the virus and attack it the next time. Scientists are harnessing this to bind to completely DAN and cut out and eventually inset novel DNA into genome of organisms. This is a new way to create transgenic organisms.

Lymph fluid contains lymphocytes, macrophages, and other WBCs. These cells meet and communicate in the?

the lymph nodes and other lymphatic tissue, such as the spleen and tonsils.

What are the chemical barriers in the first line of defense?

Chemical barriers - enzyme (lysozyme) - in tears, saliva, and sweat breaks down bacteria cell walls; stomach acid - ex. bitter taste receptors in mouth and other organs give off NITROUS OXIDE when they encounter microbes

What is clonal selection?

Clonal selection is when only the activated cells will clone (divide by mitosis) many times to produce identical cells that can interact with the same antigen.

What happens to the memory cell during secondary response?

Clone of cells identical to ancestral cells. Produces 3/4 Plasma cells for antibodies and 1 Memory B cell immediately. you may not even recognize that you were infected

CRISPR stands for

Clustered Regularly Interspaced Short Palindromic Repeats

Complement Cascade can produce chemicals that?

Complement Cascade can produce chemicals that form pores in the microbe cell membrane, chemicals that attract other macrophages and stimulate phagocytosis of a pathogen.

Complement proteins bind to?

Complement proteins bind to antibodies that are already attached to the surface of the microbe

Complement Proteins

Complement proteins participate in many aspects of our IS.

Lymph fluid contains lymphocytes, macrophages, and other WBCs. These cells meet and communicate in the lymph nodes and other lymphatic tissue, such as ?

the spleen and tonsils.

What cells are the main cells involved in transplanted organ rejection?

Cytotoxic T cells

What will happen to the MHC 1 receptors on the cell surface with abnormal proteins of cancer cells?

Cytotoxic T cells will recognize these foreign cancer antigens complexed ot MHC 1 and destroy the cancer will with perforin the same way they would do a viral infected cell

T cells are dumped as Pre-T's into the blood and they travel to

the thymus to mature

The millions/billions of T cell receptors are made in a similar way to B cells by ?

DNA rearrangement

MHC II receptors on B APC Cells can bind to an antigen on the microbe with?

their antibody receptor and then take in the microbe by endocytosis

Because not all MHCs will match between the donor and the recipient, drugs such as what are given with transplants in order to suppress the immune system? At what frequency? What effect?

Drugs such as cyclosporin are given with transplants in order to suppress the immune system. These drugs must often be given for the life of the recipient, and they make the individual more susceptible to infection

Due to mutations, cancer cells will produce BLANK that are not found in normal cells

Due to mutations, cancer cells will produce proteins that are not found in normal cells

How many receptor does 1 T cell have?

Each T cell has only 1 receptor

How many epitopes can one antigen have?

Each antigen may have multiple epitopes

Each different B cell responds to a ?

Each different B cell responds to a different epitope

What is the secondary response?

Encountering the same pathogen again - could be years later

MO/APC will do what do a microbe?

Engulfs microbe, digests it, and displays part of it on its surface bound to an MHC II receptor

Why does a person need a variety of different MHCs?

Even though MHC receptors are general in they can bind and present many different epitopes, a person needs a variety of different mHCs so that they will be able to present any type of epitope

Where does DNA rearrangement occur for Abs?

this rearrangement doesn't occur in bone marrow stem cells, but rather in the pre-B cells that come from the stem cells

What happens to T cells that have receptors that bind to self-antigens ?

those that have receptors that bind to self-antigens are destroyed

Many of the unpleasant symptoms of an infection (ex. Fever, aches, etc. ) are actually caused by the immune system chemicals trying to eliminate the infection, not by the microbes themselves. Some symptoms, of course, are caused by the microbes. For example

For example, some bacteria contain endotoxins, which are the LPS (lipopolysaccharides) that make up the other membrane of Gram-negative bacteria. Bacteria also secrete exotoxins, such as the toxins that cause botulism or tetanus

What is the thymus?

Gland over trachea, and extends over the heart in a young person. As an individual ages, the thymus shrinks considerably in size. This means that most of your T cell production will be early in life

It is believed that originally, mast cells and the allergic reaction in general were necessary to?

to fight off parasitic worm infections but bc now it's v clean in world, it's p sure. we still react to common substances w same defenses tho

Humoral Identity needs the B cell in order to produce?

to produce antibody molecules to recognize the epitopes of antigens

Why does cell-mediated immunity need cytotoxic T Cells?

to respond to an antigen - cellular response

IL-2 is released from T helper cells and then binds to receptors on the surface of the T helper cell. This causes another signal transduction pathway that eventually causes the T cell to become stimulated to ?

to undergo clonal selection.

After the signal transduction pathway starts that leads to Th production of IL2, what happens?

IL-2 is released from T helper cells and then binds to receptors on the surface of the T helper cell.

IL-2 is released from T helper cells and then binds to receptors on the surface of the T helper cell. This causes another signal transduction pathway that eventually causes what?

IL-2 is released from T helper cells and then binds to receptors on the surface of the T helper cell. This causes another signal transduction pathway that eventually causes the T cell to become stimulated to undergo clonal selection.

If a B cell is formed that binds to a self antigen, what happens?

If a B cell is formed that binds to a self antigen, it is destroyed

If a cell is infected with a virus or other intracellular parasite, the infected cell will?

If a cell is infected with a virus or other intracellular parasite, the infected cell will display a piece of the microbe in an MHC 1 receptor.


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