Immunology Flashcards
Normal WBC
5,000-10,000
Neutrophil count
50-70%
Eosinophil count
0-3%
Basophil count
Less than 1%
Lymphocyte count
20-40%
Monocyte count
2-6%
Viral CBC
Normal WBC with more lymphocytes than neutrophils
Bacterial CBC
Elevated WBC with more neutrophils
Parasitic CBC
Normal WBC with elevated eosinophils
Immunogenicity
Capacity to induce an immune response by a foreign compound.
Antigenicity
Ability to bind to Ig or immune cells. Doesn’t have to elicit an immune response.
Respiratory burst
“oxidative burst” Membrane bound NADPH system produces superoxide radicals, hyperchlorous acid, H2O2 and chloramines.
Components of the innate system
Macrophages, granulocytes, NKC, complement, physical barriers.
Granulocytes
neutrophils, eosinophils, basophils (mast cells), Monocytes (dendritic cells and macrophages)
Basophils
Allergic and Hlminth responses. Release histamine and heparin (increase BF and decrease clotting).
Eosinophils
Allergic reactions and asthma. Release free radicals and leukotrienes. Crossover to the adaptive side to stimulate T cells, act as an APC and are weakly phagocytic.
Neutrophils
First responder. Respond to cytokines within minutes then release cytokines to call in others. Strongly phagocytic. Release anti-microbial properties and extracellular traps.
Mast Cells
release histamine and heparin. In the tissue. Degranulate in response to injury, complement, antibodies or contact with an antigen. Can cause anaphylaxis.
Monocytes
give risk to dendritic cells and macrophages. 50% go to the spleen. Differentiate if stimulated by a pathogen.
Macrophages
Large phagocytes and APC. Three phases:
- ) Resting: clean up normal cellular debris
- ) Primed: engulf bacteria and presents it to T cells
- ) Hyperactivated: inflammatory cytokines and starts phagocytosing everything.
Kupffer cell
specialized macrophage in the liver. With chronic activation from ETOH or toxins they overproduce cytokines and inflammation leading to liver damage.
Natural Killer Cells
Cytotoxic Lymphocytes. Don’t need recognition or memory. Turned on my cytokines from macrophages. Kill by releasing perforins and proteases to cause membrane lysis. Don’t phagocytize. surface contact can cause pathogen to apoptose.
Complement protiens
Made by the liver. C3 is the most common. Activated by antigens and work together to signal other immune cells.
Complement Functions
Opsonization, chemotaxis, induce degranulation, lysis (MAC), acute inflammation, immune cytolysis, virus neutralization.
MAC
C6,7,8,9. Causes lysis by disrupting the osmotic balance.
Active Natural immunity
Exposure to infectious agents
Active artificial immunity
immunizations
Passive natural immunity
Maternal antibodies
Passive artificial immunity
antibodies from other sources.
Adaptive immune system attributes
antigen specific, diversity, memory, must be activated by an antigen or T helper cell.
Primary lymphatic organs
Bone marrow=B cells
Thymus=T cells
Secondary lymphatic organs
Spleen, lymph nodes, tonsils, Mucosal associated lymphoid tissue (MALT)
MHC I
On all cells. Broadcasts what’s going on inside the cell.
MHC II
On APC. presents the antigen to T helper cells.
Primary humoral response.
IgM then IgG. requires T cell to activate.
Secondary humoral response
Memory B cells activate rapidly. IgG is most involved.
Antibodies actions
Neutralization, agglutination, precipitation, opsonization, complement activation.
IgG
Secondary response. Mediates MAC formation. Fetal protection (crosses the placenta). Most common, small 21 day half life.
IgM
Acute infection. Major antibody for carbohydrates on bacterial cell walls. Pentamer, stays in the circulation. First antibody produced by the infant.
IgA
Secretory component. Mucous membranes. Blocks bacterial attachment. J chain, 6 day half life.
IgD
Monomer that acts as a receptor on mature Bcells. Required for B cell activation.
IgE
Binds mast/basophils to release histamine. Defense against parasites.
Type I hypersensitivity
IgE. anaphylaxis.
Type II hypersensitivity
IgM and IgG. Autoimmune. hemolytic disease of the newborn (rH), transfusion reaction, grave’s, Myasthenia gravis, good pasture’s disease.
T-helper cells.
Activate B cells, macrophages, neutropils, NK cells and T killer cells. Uses thier TCR and CD4 to bind an antigen presented on MHC II. Cytokine release.
T-memory cells
Recognized antigens from previous exposures.
T-regulatory cells
Suppressors. Keep immune response limited.
T-killer cells
Release cytokines to kill viruses and cancer cells. Use their TCR with CD8 to recognize MHC I antigens. perforins to kill the cell and cytokines to cause apoptosis.
Complement activation
C1 binds the antigen/antibody to activate the cascade.
