Acquired Immunity: Humoral ResponseBody Defenses: Innate and AcquiredNonspecific (Innate) Body DefensesInflammationThe Complement SystemSlide 6Acquired Immune System – Third Line of DefenseTypes of Acquired ImmunityAntigens (Nonself)Self-AntigensAllergiesHumoral (Innate) Immune ResponseCells of the Immune SystemDevelopment of LymphocytesB Cell Receptors, T Cell Receptors, and ImmunoglobulinsSlide 16Immunoglobulins and Receptors Bind To AntigensDifferent Classes of AntibodiesSlide 19B Cell Activation and Clonal SelectionSecondary Response (Immunity)Results of Antibody Binding to AntigenSlide 23Active vs Passive ImmunityMonoclonal AntibodiesSlide 26Cell Mediated Immune ResponseCellular (Cell-Mediated) Immune ResponseActivation of T and B Cells Through TH cellsTypes of T CellsSummary of B Cell ActivationSummary of the Immune ResponseOrgan Transplants and RejectionAcquired Immunity: Humoral Response• Distinction of Humoral versus Cell-Mediated Acquired Immunity• Antigens and Antigenic Determinants: Non-self and MHC proteins• Cell Types of the Humoral Response and How they Develop• B and T cell receptors and immunglobulins (antibodies)• Antibody Structure and Classes• Activation of B cells and Clonal Selection• Immunity and Secondary Response Time• Antibody Actions• Passive and Active Immunity• Monoclonal Antibodies• Cell-Mediated Immune System: T cells, GraftingBody Defenses: Innate and AcquiredDefense Systems of the BodyNon-specific defense system (Innate Immune System)•Mechanisms protect against a variety of invaders•Responds immediately to protect body from foreign materials (Innate immunity)Specific defense system (Acquired Immune System: Humoral and Cell-Mediated)•Specific defense is required for each type of invader•Also known generically as just “the immune system”Nonspecific (Innate) Body DefensesMechanical, Chemical, and Competitive BarriersSaliva and tears destroy bacteria because they contain lysozyme.Skin produces acidic sebum to limit bacterial growth and sebum fatty acids are fungistatic, urine, blood, salivaNitric oxide (NO) released by macrophages inhibit ATP productionIron-binding proteins in blood block microbial reproductionInflammationFigure 16.9c, dSerum proteins activated in a cascade.Results:•Opsonization•Chemotaxis•Transmembrane channel formation in cells tagged by antibodies (causing cytolysis)•Triggers inflammation The Complement SystemFigure 16.10Body Defenses: Innate and AcquiredDefense Systems of the BodyNon-specific defense system (Innate Immune System)•Mechanisms protect against a variety of invaders•Responds immediately to protect body from foreign materials (Innate immunity)Specific defense system (Acquired Immune System: Humoral and Cell-Mediated)•Specific defense is required for each type of invader•Also known generically as just “the immune system”Acquired Immune System – Third Line of DefenseAntigen specific – recognizes and acts against particular foreign substancesSystemic – not restricted to the initial infection siteHas memory – recognizes and mounts a stronger attack on previously encountered pathogensThe Acquired Immune System is:Types of Acquired Immunity1. Humoral Immunity•Antibody-mediated immunity in blood and lymph•Cells produce chemicals for defense2. Cellular immunity of the Cell-Mediated Immune System•Cell-mediated immunity•Cells target virally infected cellsAntigens (Nonself)Antigen: Any substance capable of exciting the immune system and provoking an immune responseExamples of common antigens•Foreign proteins•Nucleic acids•Large carbohydrates•Some lipids•Pollen grains•MicroorganismsAntigenic determinants: substances (like glycoproteins) on the surface of antigens to which the immune system actually respondsReceptor in the immune system that "fits" the antigenic determinantAntigenAntigensSelf-AntigensHuman cells have many surface proteins called major histocompatability complexes (MHC). All body cells have MHC Class I proteins. Our immune cells do not attack our own proteinsOur cells in another person’s body can trigger an immune response because they are foreign•Restricts donors for transplantsAllergiesMany small molecules (called haptens or incomplete antigens) are not antigenic, but link up with our own proteinsThe immune system may recognize and respond to a carrier-hapten combinationThis immune response can be harmful rather than protective because it can attack small molecules mounted on our own cells or small molecules normally found in the environment that bind to carriers  allergy or autoimmunityHumoral (Innate) Immune Response• Distinction of Humoral/Innate versus Cell-Mediate Response• Antigens and Antigenic Determinants: Non-self and MHC proteins• Cell Types of the Humoral Response and How they Develop• B and T cell receptors and immunglobulines (antibodies)• Antibody Structure and Classes• Activation of B cells and Clonal Selection• Immunity and Secondary Response Time• Antibody Actions• Passive and Active Immunity• Monoclonal AntibodiesCells of the Immune SystemLymphocytes•Originate from hemocytoblasts in the red bone marrow•B lymphocytes become immunocompetent in the bone marrow•T lymphocytes become immunocompetent in the thymusMacrophages (certain mature granulocytes)•Arise from monocytes•Become widely distributed in lymphoid organsDevelopment of LymphocytesT cell maturation and "education"B Cell Receptors, T Cell Receptors, and ImmunoglobulinsB cellSecreted (Exported) Immunoglobulin or Antibody (Same V and C Regions as in B cell receptors)Variable (binding) regionsReceptors on T CellsConstant regionsReceptors on B cellsT cellHumoral (Innate) Immune Response• Distinction of Humoral/Innate versus Cell-Mediate Response• Antigens and Antigenic Determinants: Non-self and MHC proteins• Cell Types of the Humoral Response and How they Develop• B and T cell receptors and immunglobulines (antibodies)• Antibody Structure and Classes• Activation of B cells and Clonal Selection• Immunity and Secondary Response Time• Antibody Actions• Passive and Active Immunity• Monoclonal AntibodiesImmunoglobulins and Receptors Bind To AntigensAgglutination of antigensDifferent Classes of AntibodiesHumoral (Innate) Immune Response• Distinction of Humoral/Innate versus Cell-Mediate Response• Antigens and Antigenic Determinants: