MICR 330-Lecture 1 (for Canvas).pptx

MICR 330: Immunology Introduction to Cell Types and Terminology August 20, 2024 What year are you at UTK? A. Freshman B. Sophomore C. Junior D. Senior E. Other What is the purpose of an immune system? Turn to your neighbor and discuss your view.  Earliest eviden...

MICR 330: Immunology Introduction to Cell Types and Terminology August 20, 2024 What year are you at UTK? A. Freshman B. Sophomore C. Junior D. Senior E. Other What is the purpose of an immune system? Turn to your neighbor and discuss your view.  Earliest evidence of immunity The first documentation of immune memory dates back to the time of the Greek historian Thucydides who recorded that the “same man was never attacked twice” while describing the plague of Athens in 430 BC How would you design the immune system? What potential problems may occur? Turn to your neighbor and discuss your view.  Basic steps of the immune response 1. Recognize the problem in the peripheral tissues. 2. Deal with the problem (antimicrobial activities, anticancer) and/or communicate the problem to other immune cells. 3. Learn from the problem to address the problem better next time.  What is Immunity? Immunity is the ability of the organism to control and clear infections and be able to respond faster and stronger when exposed to the same infection Immune system is traditionally divided into 2 distinct classes: innate (or nonspecific) and adaptive (or specific) immunity. Innate immunity controls infections early (hours-days) while adaptive immunity later (days to weeks to years). Barriers are in general part of innate immunity. Myeloid Cells: Granulocytes Myeloid Cells: Granulocytes Important in responding to allergens and infections but also the cause of allergic reactions and asthma.  Myeloid Cells: Granulocytes Important to combating infections and parasites. Myeloid Cells: Granulocytes Frontline to combating infections and possess an arsenal of antimicrobial functions. Myeloid Cells: Antigen Presenting Cells Myeloid Cells: Antigen Presenting Cells In absence of infection, exist primarily in circulation. Upon infection, possess some antimicrobial activity. Migrate into tissues and ‘differentiate’ into macrophages.  Myeloid Cells: Antigen Presenting Cells Highly ‘phagocytic’ and potent ‘lysosomes’ to combat microbes. Highly plastic cell type; each tissue contains its own unique macrophage type. Myeloid Cells: Antigen Presenting Cells Best presenter of ‘antigen’; Central to linking the innate and adaptive immune responses. Lymphocytes  Lymphocytes Identify and kill cells that are ‘sick’ (infected, cancerous, etc.). Activation and Inhibitory receptors. Lymphocytes Identify and kill cells that are ‘sick’ (infected, cancerous, etc.). Recognition of antigen through MHC class I.  Lymphocytes Recognition of antigen through MHC class II. Provide ‘help’ (cytokines, chemokines) to amplify B cell responses.  Lymphocytes Dampens the immune response to specific antigens MHC class II. Helps prevent autoimmune disease. Lymphocytes Produce a variety of ‘antibodies’ to specific antigens.  Lymphocytes Produce a variety of ‘antibodies’ to specific antigens. Fab Domain Fc Domain