L2 Immune Response 1 PDF

L2: Immune response 1 Dr. Anuar Sani, FPSK USIM  L2. IMMUNE RESPONSE 1 At the end of the topic you should be able to: Explain functions of innate immunity. Explain functions of adaptive immunity. Interrelate innate immunity to adaptive immunity. Describe antigen presentation in both inna...

L2: Immune response 1 Dr. Anuar Sani, FPSK USIM  L2. IMMUNE RESPONSE 1 At the end of the topic you should be able to: Explain functions of innate immunity. Explain functions of adaptive immunity. Interrelate innate immunity to adaptive immunity. Describe antigen presentation in both innate and adaptive immunities.  Pathogen breaking in recognition Innate response helping Adaptive response Cell Mediated Immunity Humoral (antibody (CMI) mediated) Memory & Regulation Antigen recognition by innate immune cells Innate Response Mucosal trapping/lysozymes Phagocytosis and killing Phagocytosis and presentation (helping Adaptive immunity) Complement activation via alternative pathway/MBL NK cells—recognition of altered (infected cells) via lack of HLA on surface. Lysozyme breaking bacterial peptidoglycan cell wall  Ciliated pseudostratified columnar epithelium of respiratory tract-production of mucin by goblet cells Trapping of pathogen by mucin Phagocytosis and killing by lysozyme (non- oxidative pathway) Phagocytosis and killing by oxidative pathway Phagocytosis and presentation via MHC Complement activation  As opsonin (helping phagocytosis) Chemotactic factors (calling for immune cells) Forming Membrane attack complex Roles of (MAC) complement Help clearance of cell debris (immune complex) by liver & spleen Promoting inflammation (anaphylatoxin) Pathogen neutralization (preventing pathogen adherence to cells) Bridging innate and adaptive immunity by APCs antigen presenting cells Antigen processing and presentation – antigen recognition by immune cells of adaptive immunity Receptors that mediate adaptive immune recognition: Antibody and the T cell receptor (TCR) APC presenting to T cell  CD4 subsets: generation and function Th1 cells (IFN-g) Host defense: many microbes Systemic and organ-specific autoimmune diseases Th2 cells (IL-4, IL-5) Sta 2: et, L-1 t4 Host defense: helminths T-b -, I IL-4: t6 Allergic diseases N Sta IF Naïve CD4 A 3, T cell GAT TGF- Th17 cells (IL-17) + ROR IL-6: TGF-IL-2: t, Stat Host defense: fungi, bacteria 3 Foxp3, Stat5 Organ-specific autoimmune diseases Regulatory T cells Interrelationship of CMI and HI Class (isotype) switching  HUMORAL IMMUNE RESPONSE Antibodies inactivate microorganisms by Agglutination Neutralization Antibody to toxins Antibody to microbial surface molecules that bind to host cells Opsonization Antibodies as opsonins Antibody Dependent Celullar Cytotoxicity Natural killer cells have receptors for IgG Eosinophils have receptors for IgG, IgA, and IgE Complement fixation Neutrophils, macrophages have receptors for C3b Gram negative organisms susceptible to MAC ADCC Thank You