Flashcards in Immunology Deck (31):
What is an antigen?
-A foreign substance that can cause an immune response
What is an epitope?
-immunologically active site on antigen
-interacts with antibody
What are major histocompatibility complex molecules? (MHC)
-Self-ID models. Unique for individuals
-Class 1: found on all nucleated molecules (not platelets or RBCs)
-Class 2: found on macrophages and B lymphocytes.
What are the first and second line non specific immune responses?
-Skin and mucous
-inflammatory response (vasodilation, capillary leakiness, chemotaxis, phagocytosis)
What are opsonins?
Molecules that bind to foreign cells to make them more easily eaten by phagocytic cells
What is complement?
A group of immune proteins in blood
What happens when complement is activated?
-Membrane Attack Complex Forms
-Inflammatory response increases
-Acts as opsoninizing agent, enhances phagocytosis
What are other nonspecific mechanisms of immune response?
IFN a fibroblasts and IFN b leukocytes which both inhibit viral replication.
What do NK cells do?
-Kills non-specifically but requires part of the specific immune response to pull off.
What is required for a specific immune response?
-specific recognition of an antigen
What is an antibody mediated/humoral immune response?
-Attacks bacteria or extracellular viruses
What is a cell mediated immune response?
-Attacks intracellular viruses and cancer cells, which are self cells gone bad.
Where are antibodies found?
-The surface of B lymphocytes, where they function as receptors
-solubly circulate in the plasma.
What are the 5 types of antibodies?
-15% of antibodies
-Found in secretions
-Protect against bacteria on mucus membranes
-0.2% of antibodies
-Found on surface of B lymphocytes. Help mature B lymphocytes.
-only in mammals
-Can trigger very powerful responses.
-Binds mast cells and basophils
-involved in parasitic info, allergens, hypersensitive reactions
-75%, most abundant.
-can cross placenta to defend fetus
-binds to macrophages.
-Acts against A and B RBC antigens.
What is the sequence of events in an antibody mediated immune response?
-Pathogen enters bearing antigen
-Antibody bearing B-lymphocyte recognizes and binds to antigen
-Macrophages phagocytize antigen and it's MHC is displayed on surface after processing.
-Helper T cell goes after this MHC.
-This releases cytokines, which draw in more T cells and leads to proliferation of B cells.
-Plasma cells are differentiated
-Memory cells are differentiated (remember antigens and lead to response of T cells upon second mee
What is the sequence of events in a cell mediated immune response?
Discuss B cell deficiencies
Discuss T cell deficiencies
What is DiGeorge syndrome
What is SCIDS
Describe hypersensitivity disorders
What are the four types of hypersensitivity disorders
What is required for a successful organ transplant?