22-6 B Cells and Immunity Antibody Structure Two parallel pairs of polypeptide chains One pair of chains One pair of light chains Each chain contains: Constant segments Variable segments 22-6 B Cells and Immunity Five Heavy-Chain Constant Segments Determine five types of antibodies IgG IgE IgD IgM IgA 22-6 B Cells and Immunity Variable Segments of Light and Heavy Chains Determine specificity of antibody molecule Binding Sites Free tips of two variable segments Form antigen binding sites of antibody molecule Which bind to antigenic determinant sites of antigen molecule Antigen–Antibody Complex An antibody to an antigen 22-6 B Cells and Immunity The Antigen–Antibody Complex A Complete Antigen Has at least two antigenic determinant sites to both antigen-binding sites of variable segments of antibody B Cell Sensitization Exposure to a complete antigen leads to: B cell sensitization Immune response 22-6 B Cells and Immunity Hapten (Partial Antigens) Must attach to a carrier molecule to act as a complete antigen Dangers of Haptens
22-6 B Cells and Immunity Antibody Structure Two parallel pairs of polypeptide chains One pair of chains One pair of light chains Each chain contains: Constant segments Variable segments 22-6 B Cells and Immunity Five Heavy-Chain Constant Segments Determine five types of antibodies IgG IgE IgD IgM IgA 22-6 B Cells and Immunity Variable Segments of Light and Heavy Chains Determine specificity of antibody molecule Binding Sites Free tips of two variable segments Form antigen binding sites of antibody molecule Which bind to antigenic determinant sites of antigen molecule Antigen–Antibody Complex An antibody to an antigen 22-6 B Cells and Immunity The Antigen–Antibody Complex A Complete Antigen Has at least two antigenic determinant sites to both antigen-binding sites of variable segments of antibody B Cell Sensitization Exposure to a complete antigen leads to: B cell sensitization Immune response 22-6 B Cells and Immunity Hapten (Partial Antigens) Must attach to a carrier molecule to act as a complete antigen Dangers of Haptens
ch_22_lecture_note.docx