Allergy and Immunology Flashcards
Describe the innate immune system and its 3 main components of the innate immune system?
rapid-acting, non-specific no memory with complement, macrophages, and NK cells.
what are the two parts of the adaptive immune system?
- Humoral: B-cells, plasma cells, and immunoglobulins
- Cell-Mediated: T-cells, activated macrophages and NK cells.
what are the components of myeloid cells?
- Granulocytes (neutrophils, basophils, eosinophils)
- Antigen-Presnting cells (monocytes/macrophages/dendritic cells)
- Others: mast cells, erythrocytes, platelets
where are MHC cells located?
chromosome 6
what are class I HLA antigens?
- these are types of MHC to differentiate self vs. nonself
- Class I includes HLA-A/B/C on most nucleated cells
- Present non-self material to CD8 T cells and play role in transplant rejection, neoplasms, and viral infections
what are class 2 HLA antigens?
- HLA-DP/DQ/DR
- On antigen-presenting cells
- mediate reaction between macropahges, T and B-cells
- CD4 cells recognize material presented only on Class 2 HLA antigens
what are class 3 HLA antigens?
consist of a few cytokines like TNF and lymphotoxin, some complement structures
what are the CD markers for T-cells/
CD2, CD4, CD4 and CD8
What are the types of CD4 cells?
- TH1 - Activates CD8 cells and leads to cell-mediated immunity
- TH2 - activates B cells to produce antibody and leads to humoral immunity
- Th17- plays in role in immunity against fungi, bacteria, and in auto-immune disorders
what is the role of CD8 T-cells?
cytotoxic T cells, important against viruses and neoplastic cells.
what are natural killer T-cells?
they have the CD16 and CD56 like natural killer lymphoid cells but has a MHC molecule of CD1 which recognizes primarily lipids and glycolipids
describe the B-cell lineage and diseases associated in the blood and bone marrow?
describe the B-cell lineage and diseases associated in the periphery?
describe the B-cell lineage and diseases associated in the bone marrow?
what are eosinophils involved with?
allergic reactions and immunologic defense of parasites
what are the 3 antigen-presenting cells?
- b-cells (most specific)
- monocytes/macrophages - eat opsonized cells, stimulate interleukin 1, which stimulates T-cells
- Dendritic cells - ingest pathogen, change conformation, travel to lymph node and activate lymphocytes
key things about IgG?
- contains kappa and lambda light chains
- crosses placenta
- activates complement
- Main antibody in serum
Key things about IgA?
- main igG in secretions
- Has 2 immunoglobulins (dimer) with J chain and secretory component
- Main igG secreted in breast milk
- Does not activate complement
Key things about IgM?
- 1st immunoglobulin produced in infection
- pentamer
- Useful in dx of recent illness
- Activates complement
what are the 3 complement pathways and leads to?
- classical pathway
- Lectin (mannose-binding) pathway
- Alternative pathway
- These all lead to the common terminal pathway (membrane attack complex)
what function do the 3 complement pathways all perform?
- opsonizing target cells with C3b
- inducing more inflammation with anaphylatoxins C3a, C4a, and C5a
- forming the “membrane attack complex”
describe the classical complement pathway?
- immunoglobulin (IgG/IgM) activate the classical pathway.
- C1 complex (q,r,s subunits) initiates response when a C1q subunit attaches to the antibody in an antigen-antibody complex
- C1q binds to Fc portion at least 2 igGs for 1 IgM.
- Binding activate C1q
- Activated C1q cleaves C2 and C4 forming C4b2A (c3 convertase)
- Activates C3
Describe the common terminal pathway?
- C3 when combined with either factor C4b2a or factor b activates C5
- Cause formation of C5-C9 MAC
- Mac pokes hole in bacterial cell membranes and cause the bacteria to lyse
What condition is associated with C1 inhibitor? clinical presentation?
- Hereditary angioedema is an autosomal dominant disorder caused by a decrease in C1 inhibitor activity?
- recurrent non-pitting edema with each episode lasting 1-3 days
- NO ITCHING or urticaria
- Attacks may include laryngeal obstruction and affect GI tract (abdominal pain)
- minor trauma from dental procedures can precipitate attacks