immune

passive immunity

*Naturally Acquired*: antibodies passed from mother to fetus via placenta. or through mother's breast milk. *Artificially Acquired*: injection of exogenous antibodies (‏someone's immune)

active immunity

*Naturally Acquired*: infection by contact with pathogen *Artificially Acquired*: vaccine builds immunity to a pathogen

neutralization

*antibody block specific site on virus or bacterium *prevent antigen from binding to receptors on tissue cells

2 mechanism of lethal hit

1) release perforin & granzymes by exocytosis 2) cell bind specific membrane receptor On Target cell and stimulate apoptosis

five steps of lymphocyte development, maturation & activation

1)origin, 2) maturation, 3) seeding secondary lymphoid organs and circulation, 4) antigen encounter and activation, 5) proliferation and differentiation

two main branches of adaptive system

1. Humoral (antibody-mediated) immunity 2. Cellular (cell-mediated) immunity

steps of phagocyte mobilization

1. Leukocytosis 2. Margination 3. Diapedesis 4. Chemotaxis

benefits of inflammation

1. Prevents spread of damaging agents 2. Disposes of cell debris and pathogens 3. Alerts adaptive immune system 4. Sets the stage for repair

adaptive immune system activities

Amplifies inflammatory response Activates complement

IgD

Attached to B cells function as B cells receptor

B effector cells

B lymphocytes that divide to form plasma cell clones ** primary target: ‏bacteria, fungi, parasites & some viruses

Chemotaxis

Cell movement that occurs in response to chemical stimulus

chemotaxis

Cell movement that occurs in response to chemical stimulus

directly attack & kill other cells

Cytotoxic T cells

Granzymes

Cytotoxic enzymes that initiate apoptosis

___________ & _____________kill by ingestion and destruction of particulate matter in a process called phagocytosis.

Dendritic cells and macrophages

antigen presenting cells (APCs)

Do not respond to specific antigens Play essential auxiliary roles in immunity

T cell types

Helper, Cytotoxic, Regulatory

Five major classes of antibodies

IgM, IgA, IgD, IgG, IgE

*step 3 seeding secondary lymphoid organs and circulation*

Immunocompetent but still NAIVE lymphocytes leave the thymus and bone marrow. • They "seed" the secondary lymphoid organs and circulate through blood and lymph.

innate defense system

Inflammatory response and skin and mucous membranes

characteristics of adaptive immunity

It is SPECIFIC: recognizes and targets specific antigens It is SYSTEMIC: not restricted to initial site It has MEMORY: mounts an even stronger attack to "known" antigens (second and subsequent exposures)

cellular immunity

Lymphocytes (T cells) act against target cell *Directly - by killing infected cells *Indirectly - by releasing chemicals that enhance inflammatory response; or activating other lymphocytes or macrophages ** has Cellular Targets**

IFN-alpha & IFN-beta also activate?

NK cells

*step 4 antigen encounter and activation*

Naive lymphocytes first encounter with ANTIGEN triggers lymphocyte to develop further

Cellular components of innate immunity

Phagocytes - monocytes/Macka phages , neutrophils , natural killer cells , dendritic cells.

acid mantle

Protective barrier of lipids and secretions on the surface of the skin

T cells are differentiated into two groups based on their glycoproteins: CD4 or CD8 which of the following is true of CD4 t cells

They become T-helper cells

T cells are differentiated into two groups based on their glycoproteins: CD4 or CD8 which of the following is true of CD8 t cells

They become cytotoxic T cells

Perforin

a protein, released by killer cells of the immune system, that destroys targeted cells by creating lesions like pores in their membranes.

reactivity

ability to react with activated lymphocytes and antibodies released by immunogenic reaction

Immunogenicity

ability to stimulate proliferation of specific lymphocytes and antibodies

helper T cells

activates B cells and other T induce T and B cells proliferation

self antigens

all cells are covered with variety of proteins located on surface that are not antigenic to self, but may be antigenic to others in transfusions or grafts

IgE

allergic reactions and parasitic infections cause mast cells & basophils release HISTAMINE

dendritic cells

antigen-presenting cells in the skin that phagocytize that enter tissue, then enter lymphatic to present antigen to T cells in lymph node

Defensins

antimicrobial peptides that inhibit microbial growth on skin

immunoglobulins

are protein secreted by plasma cells

Class 2 MHC proteins

bind with longer fragment recognizable by ‏ ‏helper T-cells ** signals CD4 cells that help is required

*Step 1 Origin*

both lymphocytes (T & B cells) originate in red bone marrow

natural killer cells (NK cells)

can kill cancer and virus-infected cells before adaptive immune system is activated killing them by inducing APOPTOSIS

Opsonization

coating antigen with antibody enhances phagocytosis

T effector cells

cytotoxic, helper & regulatory ** primary Target: ‏virus-infected cells & cancer cell

what are 3 cells that present antigen to T-cells

dendritic cells macrophages B cells

Class 1 MHC proteins

displayed by all cells except RBCs bind with short fragment crucial for CD8 cell activation

Antigens

foreign substances that trigger the attack of antibodies in the immune response.

complement system

group of about 20 blood proteins that can nonspecifically bind to the surface of foreign cells, leading to their destruction

without what cell there is no immune response

helper T cells

adaptive defense system

immune response

third line of defense

immune response

*Step 2 Maturation*

immunocompetence & self tolerance

complete antigens

immunogenicity and reactivity

Antibodies are also called

immunoglobulins (Igs)

area where activated immunocompetent ‏b in T-cells recirculate

in the blood and lymph

second line of defense

inflammatory response

role of complement system

insertion of MAC & cells lysis enhancement of inflammation opsonization

First line of defense

intact skin, mucous membranes and their secretions, normal microbiota

cells infected with the virus can secrete ________ that "warn" healthy neighboring cells

interferon (IFN)

antimicrobial proteins

interferons and complement proteins

incomplete antigens (haptens)

involve molecules too small to be seen so are not immunogenic by themselves

adaptive immune system

is a specific defensive system that eliminates almost any pathogen or abnormal cell in body

immunocompetence

is the ability of individual cells to recognize a specific antigen by binding to it

area where antigen Challenge and clonal selection are most likely to occur

lymph node

era seeded by immunocompetent B & T Cell

lymph node

self tolerance

lymphocytes unresponsive to own antigens

complement fixation and activation

main antibody defense against cellular antigens

IgG

main antibody of late primary and secondary immune response 75-85% of antibody in plasma crosses placenta barrier

Neutrophils

most abundant phagocytes, but die fighting; become phagocytic on exposure to infectious material

IgA

mucosal immunity help prevent entry of pathogens monomer/ dimer

destroy cells by using PERFORIN

natural killer cells (NK)

defensive mechanisms used by antibodies

neutralization, agglutination, precipitation, and complement fixation

Margination

neutrophils cling to the walls of capillaries in the injured area

Diapedesis

neutrophils flatten and squeeze out of capillaries

*step 5 proliferation and differentiation*

once selected and activated, lymphocyte proliferates & forms army of exact copies of itself. (referred to as clones) a few remain as memory cells

antigenic determinants

parts of antigen that antibodies or lymphocyte receptors bind to large chemically simple molecules

IgM

pentamer ( large then others) released by plasma cells during the primary immune response

Perforin

pore-forming protein that released by cytotoxic T cells

macrophages

present antigen to T-cells, which not only activates T-cells but also further activate microphage

Apoptosis

programmed cell death

leukocytes and macrophages exposed to the foreign substance secrete?

pyrogens

MHC proteins

recognition of "self" and "nonself" cells by the immune system

4 cardinal signs of inflammation

redness, heat, swelling, pain

Leukocytosis

release of neutrophils from bone marrow in response to leukocytosis-inducing factors from injured cells

humoral immunity

specific immunity produced by lymphocytes (B cells) that freely circulate in body fluids ** has Extracellular Target**

mucin

sticky mucus that lines digestive and respiratory tract traps microorganisms

Pyrogens

substances that cause fever

pyrogens

substances that cause fever