Key Concepts in Cellular and Adaptive Immunity

Immunity Against Extracellular Bacteria

Cells directly or indirectly involved in immunity against extracellular bacteria include: B lymphocytes / Th2 lymphocytes.

Adaptive Immunity to Viral Infections

Participants in adaptive immunity against viral infections include: NK cells / macrophages / CD4 T lymphocytes / CD8 T lymphocytes.

Mechanisms of T-Cell Induced Apoptosis

The "kiss of death" induced by a T lymphocyte to an infected cell can occur via: Unlocking granule content / FAS-Ligand interaction with FAS.

Intracellular Immunity Against Bacteria

Involved in intracellular immunity against bacteria: NK cells / macrophages / neutrophils / IgG-producing B cells / CD8 T lymphocytes.

Viral Evasion Mechanisms

Viruses induce the synthesis of viruquinas, which are: Proinflammatory cytokines homologous to true cytokines.

Cytotoxic Lymphocyte Populations

Lymphocytes with cytotoxic activity are distinct populations that can: Not express CD4 or CD8 / Express CD4 / Express CD8 / Secrete TNF-alpha.

Cytotoxic T-Cell Expression

Cytotoxic T-cell activity may involve: Alpha-beta chain / CD4 (to interact with MHC II) / CD8 / FAS protein.

Calcium-Dependent Cytotoxicity

Cellular mechanisms of calcium-dependent cytotoxicity include: NK cells / NKT cells / CD8 lymphocytes.

Apoptosis Signal Transduction

Required components for apoptosis or programmed cell death include: Fas / Fas ligand / TNF / Lymphotoxin / Lymphotoxin-receptor.

NK and NKT Cell Cytotoxicity

The NK cell cytotoxic process differs from NKT cells in that only NK cells can exercise: ADCC.

Cytotoxic Cell Mechanisms

Cells that can act as cytotoxic cells include: CD4 T lymphocytes / neutrophils / eosinophils.

NK Cell Regulation

The main molecule that inhibits NK cell activation is: MHC I.

ADCC Mechanism

The mechanism of ADCC is activated when the NK cell recognizes a target cell directly via: A portion of a bound IgG Fc region.

Cytokine Functions

• CD4 Th1 cell proliferation: IL-2.
• B cell differentiation to secrete IgA: IL-5.
• IL-4 deficiency effects: NK cell activation / Isotype switching to IgE / Th2 lymphocyte proliferation.

Interferon Type II Effects

Effects of Interferon Type II include: Inducing expression of MHC Class I and II / Th1 differentiation / IgG isotype switching / Macrophage activation.

Th1 Response Components

A Th1 response involves: IL-2 / IFN-gamma / Lymphotoxin.

Toxic Shock and Parasite Defense

• Lethal toxic shock induction: Bacterial superantigens / Polyclonal T cell activation / IL-2.
• Cytokines in defense against helminth parasites: IL-4 / IL-5.
• Cytokines responsible for B cell class switching: IL-4 (IgE) / IFN-gamma (IgG) / IL-5 (IgA).