CELLMEDIATED IMMUNITY Antigen presentation Formation of viral proteins

CELL-MEDIATED IMMUNITY Antigen presentation • Formation of viral proteins by macrophage • Formation of antigen-MHC complex TH cell activation • Binding of TH cell to antigen-MHC complex • Release of cytokines from macrophage • Activation of TH cell to release cytokines TC cell activation • Activation of virgin and memory TC cells by cytokines • Promotion of mitosis and differentiation of TC cells Cellular destruction • Binding of effector TC cell to infected body cell • Induction of cell lysis by release of perforins.

HUMORAL IMMUNITY Antigen presentation • Formation of viral proteins by macrophage • Formation of antigen-MHC complex TH cell activation • Binding of TH cell to antigen-MHC complex • Release of cytokines from macrophage • Activation of TH cell to release cytokines B cell activation • Activation of virgin and memory B cells by cytokines • Promotion of mitosis and differentiation of B cells Antibodies production • Release of circulating antibodies into the bloodstream from the plasma cells

ROLE OF CYTOKINES IN ACQUIRED IMMUNITY Interleukin 2 TNF-b & IFN-g Interleukin 1 Cytokine Site of Release Stimulus Effects Interleukin-1 Macrophage • Antigen-MHC complex • Release of IL-2 release from TH cells Interleukin-2 TH cell • Antigenic stimulation • IL-1 signals • Induction of IL-2 receptor production • Activation of virgin & memory TC and B cells TNF-b Activated TC cell • Activated TC cells • Cytotoxicity of target cells IFN-g Activated TC cell • Antigen-MHC complex • Activation of macrophages • Increased expression of MHC TNF-b IFN-g Tumor Necrosis Factor b Interferon g

STRUCTURE OF IMMUNOGLOBULIN Glycoprotein molecules produced by plasma cells in response to an antigen Light Chain Hinge VL CL VH CH 1 CH 2 CHO CH 3 Heavy Chain Constant Region Variable Region CHO Domains

STRUCTURES & FUNCTIONS OF IMMUNOGLOBULINS Papain Pepsin Fc Peptides Fab Fc Antigenic binding Effector functions F(ab’) 2 Antigenic binding & No effector functions

IMMUNOGLOBULIN DIVERSITY

IMMUNOGLOBULINS IN ACTION Opsonization

IMMUNOGLOBULINS IN ACTION Exotoxin Neutralization

IMMUNOGLOBULINS IN ACTION Viral Neutralization

IMMUNOGLOBULINS IN ACTION Complement fixation

IMMUNOGLOBULINS IN ACTION Cytotoxicity

IMMUNOGLOBULINS IN ACTION Agglutination

IMMUNOGLOBULINS IN ACTION

PRIMARY AND SECONDARY IMMUNE RESPONSES

ACTIVE VERSUS PASSIVE IMMUNITY Acquired Immunity Naturally Acquired Artificially Acquired