Jackson The Immune System At Work

Front 1

Describe at least 4 ways in which antibody, either alone or in combination with other immune system elements, can prevent, clear or neutralize an infectious agent

Back 1

-*opsonization (Ab-assisted phagocytosis)
-IgG/IgM + complement-mediated lysis
Ab + antigen complexes
Ab neutralization of toxins & viruses
*Ab interference w/virus/bacteria cell attachment
secretory IgA/IgG on mucosal surfaces
IgE in anti-parasitic defense
antibody-dependent cellular cytotoxicity (ADCC)

Front 2

Explain the role of dendritic cells in activating the immune response

Back 2

capture antigen & present peptides to T cells in lymph node
orchestrate immune response

Front 3

Describe the general role(s) of T cells in a typical virus infection

Back 3

CD8+ cells kill cells that display viral antigen on them, only recognize a specific antigen

CD4+ -> Th1/2 to stimulate antibody production specific to virus protein for neutralization

Front 4

Describe the general role(s) of cytotoxic T-cells in a typical virus infection

Back 4

MHC-restricted cytolysis of cells presenting viral antigen on surface, inducing apoptosis (by releasing Fas ligand, granzymes, perforin)

Front 5

Describe Th1 cells

Back 5

releases IL-2, IFN-y
macrophage activation
B-cell activation & production of IgG & others

Front 6

Describe Th2 cells

Back 6

releases IL-4, IL-5
general activation of B cells to make antibodies

Front 7

Describe Th17 cells

Back 7

release IL-17 which causes release of inflammatory cytokines & recruit neutrophils

Front 8

Describe Treg cells

Back 8

CD4+, CD25+
releases IL-10, TGF-B
inhibits antigen-specific lymphocyte reactions

Front 9

Describe general characteristics and defensive roles of NK cells

Back 9

mediates ADCC (antibody-dependent cellular cytotoxicity)
-MHC-I sends inhibitory signals, thus if decreased MHC-I expressed, it will induce apoptosis
- recognizes > 1 antigen (not antigen specific)

Front 10

Describe general characteristics and defensive roles of NKT cells

Back 10

small population of lymphocytes that express surface molecules characteristic of NK & T cells. Express the aB T cell receptor & some NK cell markers.
- have been shown to activate or suppress innate & adaptive immune responses, primarily to glycolipid antigens

Front 11

Describe general characteristics and defensive roles of T cells

Back 11

MHC-I restricted CD8+ mediated cytolysis
recrution of inflammatory cytokines & neutrophils (Th17)
macrophage & B-cell activation (Th1,2)
inhibition of antigen-specific lymphocyte rxns (Treg)

Front 12

List the most effective immunologic responses generally against viruses

Back 12

inferferon, NK cells, T cells, neutralizing antibody

Front 13

List the most effective immunologic responses generally against:
1. intracellular bacteria

Back 13

1. CD8+ T cells, NKT cells, TH1, granuloma

Front 14

List the most effective immunologic responses generally against fungi

Back 14

Neutrophil phagocytosis, T cells

Front 15

List the most effective immunologic responses generally against parasites:
1. protozoan parasites

Back 15

1. sIgA, phagocytosis, CD8+ and CD4+ T cells

Front 16

List 5 mechanisms used by pathogens to avoid immunologic destruction

Back 16

anti-phagocytic capsule
inhibit phagosome-lysosome fusion
general immune suppression via inhibition of cytokines
antigenic variation (HIV, etc)
viral latency

Front 17

what are some cellular immune mechanisms?

Back 17

Phagocytosis and intracellular killing
MHC-restricted CTL(CD8+)-mediated cytolysis
NK cell and NKT cell activity
ADCC via killer cells
Granuloma formation
Effector T cell subsets and their activity

Front 18

describe antibody-dependent cellular cytotoxicity & what cells mediate it.

Back 18

antibody binds antigens on surface of target cells. Fc receptors on NK cells recognize bound antibody. Cross-linking of Fc receptors signals NK cell to kill target cell which dies by apoptosis.
- NK cells, macrophage & eosinophil can utilize this.

Front 19

describe granulomas & their mechanism of formation

Back 19

space-occupying chronic inflammatory lesions that form due to partial activation of macrophages by IFN-y produced by TH1 cells
- tuberculosis, leismaniasis, & schistosomiasis can cause formation

Front 20

List the most effective immunologic responses generally against parasites:
1. parasitic worms

Back 20

1. IgG & IgE mediated ADCC, eosinophils

Front 21

List the most effective immunologic responses generally against:
1. extracellular bacteria

Back 21

1. Phagocytosis, antibody, complement