Humoral Immunity Lecture 21E PDF

Humoral Immunity Humoral immunity is an indirect method of defense B cells produce antibodies that bind to antigens and tag them for destruction by other means B Lymphocytes (B Cells) Development in the bone marrow B cell selection (Home-schooled) – B cells that react to self-antigens undergo apopto...

Humoral Immunity Humoral immunity is an indirect method of defense B cells produce antibodies that bind to antigens and tag them for destruction by other means B Lymphocytes (B Cells) Development in the bone marrow B cell selection (Home-schooled) – B cells that react to self-antigens undergo apoptosis, same as T cell selection Self-tolerant B cells – Synthesize antigen surface receptors, divide rapidly, produce immunocompetent clones Leave bone marrow and colonize same lymphatic tissues and organs as T cells B Cell Activation Plasma cells – Larger, more RER – Live 4-5 days – Secrete 2,000 molecules/sec Memory Antibodies Immunoglobulins (Igs)→ defensive gamma globulins – Blood plasma, tissue fluids, secretions, membranes Y-shaped molecule with variable and constant regions – Variable region is antigen specific – Constant region is the same within each class and determines the action 5 classes: IgA, IgD, IgE, IgG, IgM Genetic recombination produces endless combinations of antibody genes → somatic recombination B cells in the lymph nodules → somatic hypermutation Antibodies Responsible for Type I natural passive immunity to the newborn via breast milk hypersensitivity Also responsible for incompatibilities w/in Secondary most abundant antibodes the Rh mother and blood system blu fetus Responsible for hemolytic the disease of newborn very small Responsible for natural passive Immunity to the First In to form primary Immune response Largest ABO blood group fetus Antibodies To Summarize…