V. ADAPTIVE IMMUNE RESPONSE

Phagocytic cells that process antigen and express it on the cell surface associated with MHC I or II molecules

Monocytes/macrophages and Dendritic cells

Nonphagocytic cells that attach to antigens in their native form, process antigens, and express them on their surface associated with MHC II molecules

B cells

B cell

• The B cell antigen receptor is monomeric ______.

• The B cell surface receptors have _____ identical antigen-binding pockets—the Fab portion of an antibody monomer. 

• IgM or IgD

• two

T cells

• The T-cell receptor consists of ____ nonidentical _____; in close proximity is the co-receptor ____.

• T cells recognize antigens that were processed by other cells.

• T-helper (TH) cells have ____ on their surface that interacts with ____ on the antigen-presenting cell.

• two ;  peptides ; CD3

• CD4 ; MHC II

TH cell activation

a) Occurs when TH cells recognize an antigen

b) Requires _____ cell contact and cytokines such as _____

direct ;  IL-1 and IL-2

CTLs have _____ on their surface, which interacts with ____ on the antigen-presenting cell.

CD8  ; MHC I

a subset of T-helper cells, that secrete cytokines that activate other cells involved in the response

TH 1 cells

are inflammatory reaction cells stimulated by cytokines from TH 1 cells.

Monocytes and macrophages

Cell-Mediated Immunity is mediated by

Mediated by TH 1 cells,

are activated by cytokines from TH 1 cells and then destroy targets by cell-to-cell contact, its main function is to destroy virus infected cells.

CTLs

they kill target cells without being previously sensitized, are regarded as part of innate immunity,

NK cells

are of lymphoid lineage and share physical and functional characteristics of NK cells and T cells.

NK T cells

NK T cells produce a number of cytokines including ____

IFN-γ and IL-2.

T and B cell interactions

• B cell processes and presents the antigen, stimulating the ___ cell to produce cytokines.

• The ______ stimulate the B cell to divide and differentiate into a ____ or a _____ that will synthesize antibody.

• TH2 ;

• cytokines ; memory B cell ; plasma cell

Cytolytic effector cells (e.g., NK cells and PMNs) can lyse antibody-coated target cells if there is direct contact

Antibody-dependent cell-mediated cytotoxicity (ADCC):