Bio Immune Flashcards
Antibody structure
Constant region, variable region
Heavy chain, light chain
Epitope - antibody binding site
Paratope- antigen binding site
Antibody sites that bind epitopes on antigens must differ depending on cytokines being tested
Effect of Tonicity on red blood cells
Hypotonic - low osmolarity, water absorption
Isotonic - no movement of water
Hypertonic - high osmolarity, water loss
Innate immunity characteristics
Nonspecific
Composed of defenses that are always active against infection but lack the ability to target specific invaders.
Includes antimicrobial molecules and phagocytes ( cells that ingest and destroy pathogens): dendritic cells and macrophages, also activate inflammatory response by activating cytokines that trigger an influx of immune cells from the blood.
Monocytes which can mature into macrophages and neutrophils
Adaptive immunity characteristics
Defenses that target specific pathogens
Slow to act but can maintain immunological memory of an infection.
Specific
Contains B cells and T cells
B cells secrete antibody molecules that bind to an antigen
T cells recognize antigens displayed on cells
Some T cells help to activate B cells and other T cells while other can attack infected cells directly.
Humoral immunity- driven by B cells and antibodies
Cell mediated immunity- driven by T cells
Spleen characteristics
Location and storage of B cells which turn them into plasma cell to produce antibodies
Storage for white blood cells and platelets
What includes in gut- associated lymphoid tissue, Peyers patches and appendix?
GALT:Tonsils and adenoids
Peyers patches: in the small intestine
Appendix: limphoid aggregates
Leukocytes
Produced in the bone marrow through hematopoiesis.
Divided into: granulocytes ( neutrophils, eosinophils and basophils) and agranulocytes. Presence of granules in the cytoplasm that contain toxic enzymes and chemicals which can be released by exocytosis are effective against bacterial, fungal and parasites.
They both come from hematopoietic stem cells ( also give rise to red blood cells and platelets)
Agranulocytes characteristics
Lymphocytes - antibody production , immune cell modulation and ratcheted killing of infected cells
Monocytes- phagocytic cells, become macrophages in tissues
Innate immune system systems
Complement system - number of proteins in the blood that act as a nonspecific defense against bacteria. Activated through classical pathway ( binding of an antibody to a pathogen) or alternative pathway ( doesn’t require antibodies)
Proteins make holes in the cell wall of bacteria. Increase effectiveness of antibodies by helping recruit and activated phagocytes
Interferons - protein prevent viral replication. Against viruses. Upregulate MHC 1 and 2 classes for better detection of the infected cells
Cells of the innate immunity
Macrophages come from monocytes. They release cytokines - chemical substances that stimulate inflammation and recruit additional immune cells to the area.
Mast cells - release histamine and other chemicals to promote inflammation
Granulocytes : neutrophils (bacteria), eosinophils ( parasites), basophils - inflammatory response like allergy
Natural killer cell - destroys the body’s own cells that have become infected.
Dendritic cell - presents antigen to adaptive immune cells
Cell mediated response
Inflammation, phagocytosis, antigen presentation, activation of specific immunity
MHC
1 class endogenous pathway binds antigens that come from the inside of cell (T cells)
2 class exogenous pathway ( macrophages)
Adaptive immunity cells
B cell - produce antibody by converting into plasma cells. Humoral immunity
Killer T cell destroys an infected cell, other T cells coordinate the immune response - cell mediated immunity
Active vs passive immunity
Immunization is active
Passive - transfer of antibodies
Activation of B lymphocytes by helper T cells
Mature B cells inactive until their receptors bind a specific foreign antigen breaking it down into smaller fragments. Then MHC2 binds those fragments and presented them on the surface so T helper cells can recognize them by releasing cytokines that stimulate B lymphocytes proliferation.
Lymphoid tissue
Lymph node - houses leukocytes
Lymph vessel - transports lymph
Thymus - T cell maturation
Spleen - filters and stored blood
What cells release cytotoxins to induce apoptosis of the infected cells?
Natural killer ( innate)
Cytotoxic T cells ( adaptive)
Difference between adaptive and innate
What is clonal selection?
Preferential replication of B and T lymphocyte clones that respond to a specific antigen. It requires: a variety of B and T cell clones, antigen receptors for a specific pathogen, replication of antigen responsive clones
Cells and their function
Helper T cells functions
