免疫毒理学 - 苏州大学.ppt

Immunotoxicology免疫毒理学 苏州大学放射医学与公共卫生学院 卫生毒理学教研室 李建祥 Objectives Biology of the immune response Types of immune responses and disorders Tests for quantifying immunity Testing immunotoxicity in animal models Some specific chemicals Importance of immune system Protect against potentially harmful environmental agents Biology of the immune response Innate v acquired immunity Immune biology - 2 Innate immunity Non specific Barriers + pro-inflammatory mechanisms Includes Complement NK cells Mucosal barriers Phagocytic cells Immune biology - 3 Acquired immunity Specific Requires period of prior exposure Increases in magnitude with continuing exposure Variable Immune biology - 4 Lymphocytes B cells/plasma cells – humoral T cells – cell mediated others Antigen presenting cells Play an important role in processing antigen allowing recognition - NB for T cells. Immune biology - 5 Humoral immunity Antigens, haptens, and epitopes B lymphocyte stimulated by foreign antigen – section recognised is epitope - enhanced by macrophage but will occur alone Proliferation + transformation to plasma cells – germinal centres in lymphoid tissue Production of specific circulating antibodies Immune biology - 7 Classes of antibody IgG – largest proportion – subclasses – may be cytophilic rather than circulating IgM – pentamer – initial response IgA – dimer – j chain – secretory piece – prevent binding IgE – parasites – allergy - eosinophils IgD – B lymphocytes – antigen recognition Classes of antibody Immune biology 9 Function of antibodies Agglutination - neutralisation Opsonisation – stimulating phagocytosis Complement binding Interaction with cell mediated immunity Role of cytophilic antibodies Cell activiation Complement activation Immune biology - 11 Cell mediated immunity T lymphocytes T4 ‘helper’ cells B lymphocyte and macrophage regulation Th1 and Th2 forms (Th2 IL4 and IL5) Recognise antigen associated with MHC II molecules T8 ‘suppressor’/‘cytotoxic’ cells Recognise and lyse virus