Pathopysiology: Elements of Immune System and Their Role in Immunity

Active Natural

-Active natural immunity occurs as a result of exposure to an antigen -The immunity is not immediate, but develops over time -It lasts a long time, perhaps a life time -Antibodies are produced as a response to an antigen -Memory B and T cells remain and initiate a faster secondary immune response on re-exposure to same antigen Describes which type of Active immunity?

Kinins (Bradykinins)

-Cause vasodilation -Increased permeability (edema) Pain Which chemical mediator does this describe?

Antigens

-Complex proteins that activate the immune system to produce antibodies -Represent self are present on an individual's plasma membrane and are generally tolerated by the immune system -Coded by genes inherited from both parents and are identical only in identical twins Describe what element of the immune system?

Leukotrienes

-Derived from mast cells and basophils -Cause contraction of bronchiolar smooth muscle -Have a role in inflammation Which chemical mediator does this describe?

Non self-cells

-Foreign antigens trigger a specific response -Lymphoid tissue captures inhaled or ingested antigens and triggers a response -Memory cells remember stored response if antigen reappears -Defensive is only effective if previously developed antibodies are present -Malignant neoplastic cells seen as foreign are removed These are known as?

Interleukins

-Group of cytokines -Indulges in immune cell differentiation and activation describes which element of the immune system?

Passive Natural

-IgG is transferred from mother to fetus across the placenta -Maternal antibodies are transferred in colostrum and breast milk Describes which type of Passive immunity?

self-cells

-Immune system ignores proteins on individual cells-demonstrates tolerance -Some cancer cells are seen as self and not removed by immune system -Tolerance to self-antigens prevents improper responses These are known as?

Active Artificial

-It develops when a specific antigen is introduced (for example a vaccine) -Antibodies are produced but are not the result of a disease -A toxoid vaccine is a weakened bacteria toxin that acts as an antigen -A booster is an additional immunization given to stimulate an effective secondary response Describes which type of Active immunity?

Macrophages

-Large phagocytic cells that intercept and engulf foreign material -Display foreign antigens to lymphocytes and initiate the immune response Describe what element of the immune system?

Prostaglandins

-Lipids that cause inflammation -Vasodilation -Increased permeability -Pain Which chemical mediator does this describe?

Primary

-Occurs when person is first exposed to antigen -Antibodies or sensitized T lymphocytes initiated -Process takes 1-2 weeks -Seroconversion occurs and level of antibody falls describes what type of immune response?

Secondary

-Occurs with repeat exposure to antigen -Memory T cells initiate quick production of antibody -Rapid response -Higher antibody levels than primary response Describes what type of immune response?

Histamine

-Released from mast cells and basophils -Stimulating other chemical mediators -Inflammation, chemotaxis, and phagocytosis Which chemical mediator does this describe?

Passive Artificial

-Results from the injection of antibodies from a person or animal into another individual (for example rabies antiserum) -Can be given to an exposed individual to reduce the effects of a disease (for example Hepatitis B) Describes which type of Passive immunity?

Monokines

-Type of cytokine that mediates an immune response -Attract neutrophils for phagocytosis via chemotaxis describes which element of the immune system?

1. Passive Natural 2. Passive Artificial

2 Types of Passive Immunity:

1. Active Natural 2. Active Artificial

2 Types of active immunity:

Answer: The baby has passive natural immunity. Why? IgG antibodies would cross the placenta from mother to fetus, giving the baby immunity to the cold. Why the others are incorrect: The baby has active natural immunity. Incorrect because: Active natural immunity will not prevent the baby from catching this cold. The baby has active artificial immunity. Incorrect because: Active artificial immunity occurs after a vaccination. The baby has passive artificial immunity. Incorrect because: Passive artificial immunity would require an antiserum.

A pregnant woman has a cold one week prior to delivering a healthy baby. The sibling of this baby currently has the same cold but the pediatrician is not concerned about the baby catching the cold. Why is the pediatrician not concerned? The baby has active natural immunity. The baby has active artificial immunity. The baby has passive natural immunity. The baby has passive artificial immunity.

a person is first exposed to an antigen and develops antibodies or T lymphocytes are sensitized. This generally takes 1-2 weeks.

A primary immune response occurs when? how long does it take?

repeat exposure and is rapid.

A secondary response occurs with a?

Measles or German Measles vaccine generates antibodies and grants immunity.

An example of Artificial Active would be?

Antibodies given to minimize severity of a recent exposure to a microbe.

An example of Artificial Passive would be?

Neonate has short-term immunity to diseases that the mother has developed antibodies against.

An example of Natural Passive would be?

Once you have chicken pox or measles, you generally do not get it again.

An example of natural active would be?

the general circulation as well as in lymph structures.

Antibodies are found in?

a class of proteins called immunoglobulins, and they bind to specific antigens in a way similar to a lock and key and destroy them.

Antibodies are?

foreign substances or proteins found on cells that activate the immune system to produce specific antibodies.

Antigens (immunogens) are?

Vaccine (live or attenuate) is injected into host. No illness results, antibodies form. Yes

Artificial Active Mechanism: Memory?

Antibodies injected into person (antiserum). No

Artificial Passive Mechanism: Memory?

1. Histamine 2. Kinins (Bradykinins) 3. Prostaglandins 4. Leukotrienes

Chemical Mediators of the Immune System: (4)

1. Antigens 2. Macrophages 3. Lymphocytes 4. Additional Classes of White Blood Cells 5. Mast cells 6. Phagocytic cells 7. Monokines 8. Interleukins

Elements of the Immune System: (8)

Activates B cells

IdD's function:

-Bathes mucous membranes (GI tract, respiratory, and genitourinary) -protects them from microorganisms and toxins and also provides protection to neonates

IgA's functions: (2)

Links to allergens and causes release of histamine and other chemicals resulting in inflammation

IgE's function:

Activates complement, forms natural antibodies, in involved in ABO blood type incompatibility reaction

IgM's function:

1. actively by the host being exposed to an antigen that it recognizes as foreign 2. passively by immunity being transferred from another source.

Immunity can be acquired 2 ways:

a specific class of proteins that bind to specific antigens to destroy them.

Immunoglobulins (antibodies) are?

1. IgG 2. IgM 3. IgA 4. IgE 5. IgD

Immunoglobulins 5 classes are?

macrophages

Monokines are released from?

Pathogens enter body and cause illness-antibodies form. Yes

Natural Active Mechanism: Memory?

T lymphocytes (T cells)

Natural Killer T cells: destroy foreign cells, virus-infected cells, and cancer cells Memory T cells: stimulate an immune response on re-exposure to antigen Helper T cells: activate B & T cells Fall under which type of Lymphocyte?

Antibodies move from mother to child across placenta and in breast milk. No

Natural Passive Mechanism: Memory?

White Blood Cells

Neutrophils: for phagocytosis and active in inflammatory process Basophils: bind IgE and release histamine in anaphylaxis Eosinophils: allergic response and defend against parasites Monocytes: become macrophages Are additional classes of?

Lymphocytes

Primary white blood cell that recognizes and reacts to antigens are of three types: -B lymphocytes (B cells): differentiate to form antibody producing plasma cells and are involved in humoral-mediated immunity -T lymphocytes (T cells): activated in the thymus and activate other cells in the immune system directing cell mediated immunity Describe what element of the immune system?

1. lymphoid structures 2. immune cells 3. tissues concerned with immune cell development 4. chemical mediators.

The immune system consists of? (4)

bacteria, viruses, and foreign substances.

The immune system has evolved to protect the body against? (3)

an individual's chance of acquiring a disease when a large number of people in the population are vaccinated.

The occurrence of many diseases has declined where vaccination rates have been high, creating "herd immunity," thus decreasing?

Answer: The unvaccinated person would exhibit a primary immune response and have flu symptoms. Why: The unvaccinated person would exhibit a primary immune response and have flu symptoms as antibody production can take 1-2 weeks on initial exposure. Why the others are incorrect: The vaccinated person would exhibit a primary immune response and not have flu symptoms. Incorrect beacuse: The vaccinated person would exhibit a secondary immune response. The unvaccinated person would exhibit a secondary immune response and have flu symptoms. Incorrect because: The unvaccinated person would exhibit a primary immune response, not a secondary response. The vaccinated person would exhibit a secondary immune response and have flu symptoms. Incorrect because: The vaccinated person would not have flu symptoms.

Two people are exposed to the flu while working in a small office. One person had their flu shot and one did not. Which outcome can be expected due to this exposure? The unvaccinated person would exhibit a primary immune response and have flu symptoms. The vaccinated person would exhibit a primary immune response and not have flu symptoms. The unvaccinated person would exhibit a secondary immune response and have flu symptoms. The vaccinated person would exhibit a secondary immune response and have flu symptoms.

1. natural active immunity (antibodies form in response to pathogens) 2. artificial active (antibodies form in response to a vaccine) 3. natural passive (antibodies pass via the placenta or breast milk) 4. artificial passive (antibodies are injected into the person in the form of an antiserum).

Types of acquired immunity include? (4)

IgM

What Immunoglobulin is bound to B lymphocytes in circulation. & Is the first to increase in the immune response?

-Activates complement, antibacterial, antiviral, and antitoxin antibodies. -Crosses placenta and creates passive immunity for neonate

What are IgG's functions: (2)

1. the early rapid responders of innate immunity (skin, mucous membranes, phagocytic leukocytes, special lymphocytes, and several plasma proteins) 2. the slower responders of adaptive immunity (antibodies and T and B lymphocytes).

What are the two defense systems that cooperate to protect the body?

1. Primary 2. Secondary

What are the two types of immune responses?

Phagocytic cells

What element of the immune system ingest (phagocytosing) harmful foreign particles, bacteria, and dead or dying cells

Mast cells

What element of the immune system release chemical mediators (ex. Histamine)

IgA

What immunoglobulin is found in secretions like tears and saliva, in mucous membranes and colostrum?

IgG

What is the most common antibody produced in primary and secondary immune response?

tissue damage can occur and an autoimmune disease can develop.

When an immune response develops against a host's own cells what can occur?

IgD

Which immunoglobulin attaches to B cells?

IgE

Which immunoglobulin binds to mast cells in skin and mucous membranes?

Answer: Differentiates between self and foreign cells Why? The immune system differentiates between self and foreign cells. Why the others are incorrect: Immediately responds to antigens Incorrect because: A primary immune response takes 1-2 weeks. Responds to bacteria but not viruses Incorrect because: The immune system responds to bacteria, viruses, and toxins. Helps the host develop herd immunity Incorrect because: Herd immunity occurs when the likelihood of contracting a disease is less in a vaccinated population.

Which statement describes a role of the immune system? Immediately responds to antigens Responds to bacteria but not viruses Helps the host develop herd immunity Differentiates between self and foreign cells

Answer: The immune system ignores self-proteins. Why? Tolerance is the immune system ignoring self proteins, preventing an improper response. Why the others are incorrect: The immune system remembers a stored response. Incorrect because: A secondary response is the immune system responding to a stored response. The immune system sees some cancer cells as self. Incorrect because: This is not tolerance as the immune system should see cancer cells as foreign. The immune systems sees malignant cells as foreign. Incorrect because: A primary response is triggered when the immune system sees foreign cells.

Which statement describes the immune system demonstrating tolerance? The immune system remembers a stored response. The immune system sees some cancer cells as self. The immune systems sees malignant cells as foreign. The immune system ignores self-proteins.

Answer: 1. The immunity is short-term Why? Newborn passive immunity is short-term. 3. Newborns have natural passive immunity. Why? Newborns have natural passive immunity. 4. Newborns receive antibodies in colostrum. Why? Maternal antibodies pass to the newborn in colostrum, offering natural passive immunity. 5. Newborns receive antibodies across the placenta. Why? Maternal antibodies pass to the newborn across the placenta, offering natural passive immunity. Incorrect: 2. Newborns have natural active immunity. Incorrect because: Natural active immunity occurs after contracting a disease.

Which statements about newborn immunity are correct? Check all that apply: 1. The immunity is short-term. 2. Newborns have natural active immunity. 3. Newborns have natural passive immunity. 4. Newborns receive antibodies in colostrum. 5. Newborns receive antibodies across the placenta.