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Immunology 3
drew
45
Medical
Graduate
05/16/2009

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Term
AIRE
Definition
required for thymic expression of tissue-specific proteins. Inactivation results in autoimmune polyendocrinopathy.
Term
APECED
Definition
(Autoimmunity Polyendrocinopathy-Candidiasis-Ectodermal Dystrophy) Syndrome. Mutations in the AIRE gene. Results in hypoparathyroidism, adrenal insufficiency, primary hypogonadism, and chronic candida infections.
Term
CTLA-4
Definition
on the surface of Helper T cells and transmits an inhibitory signal. Polymorphisms are associated with autoimmune diseases.
Term
Autoimmunity Lymphadenopathy Syndrome, ALPS:
Definition
Defect in fas gene. massive lymphoproliferation varying degrees of autoimmune hemolytic anemia, glomerulonephritis, vasculitis, and other autoantibodies.
Term
fas
Definition
receptor on cells that induces programmed cell death when the receptor is ligated. Mutation results in ALPS
Term
FoxP3
Definition
essential gene for t regs.
Term
Sympathetic ophthalmia is an example of what?
Definition
exposure of sequestered self antigens
Term
central tolerance
Definition
In generative lymphoid organs, immature lymphocytes recognize self antigen. Usual mechanism is apoptosis.
Term
peripheral tolerance
Definition
In peripheral tissue, mature lymphocytes recognize self antigen and become nonreactive. Occurs by one of many mechanisms.
Term
Mechanisms of self tolerance
Definition
1. Apoptotic cell death (clonal deletion).
2. Functional inactivation without cell death (clonal anergy).
3. Clonal ignorance.
4. Suppression of lymphocyte activation and effector functions by regulatory lymphocytes.
Central tolerance is mostly apoptosis and peripheral tolerance is all of the above.
Term
clonal ignorance
Definition
Self reactive lymphocytes may fail to recognize or respond to some self antigens in the periphery, but the cells neither die nor become anergic.
Term
Entry of HIV requires binding to what surface proteins
Definition
CD-4 and chemokine coreceptors either CCR5 or CXCR4. CCR5 is present primarily on memory CD4 positive T-cells whereas CXCR4 is most abundant on naïve CD4 T-cells.
Term
What do HIV proteins nef and Vpu do?
Definition
Nef downregulates MHC-I
Nef and Vpu downregulate CD4
Term
Nef protein
Definition
Negative factor - major virulence factor of HIV. Activates T cells through TCR-z to insure infection, downregulates CD4 and 28, MHC I and II. **Only downregulates HLA-A and B, it leaves C and E which don't present viral antigens. This way it evades CTLs and NK cells.
Term
Vif protein
Definition
HIV protein. Inhibits APOBEC3G by redirecting ubiquitin ligase against it.
Term
APOBEC3G
Definition
innate defense protein against virus infection. It can deaminate “C” to give “U”. “U” is the equivalent of “T” in DNA, and the change from C to T executed randomly throughout the viral genome results in lethal (against the virus) hypermutation.
Term
Which Th response favors killing of intracellular pathogens
Definition
Th1 favors by IFN gamma which activates macrophages to kill. Th2 inhibits by IL-10 and IL-4 production.
Term
Superantigens bind to which subunit of which component of T cells?
Definition
V beta subunit of MHC II
Term
B-1 cells
Definition
Polyspecific esp for LPS, quick IgM response independent of T-cells.
Term
MZ B cells
Definition
Marginal zone b-cells. Found in spleen, similar to B-1 cells in that they produce a rapid IgM response independent of T cells.
Term
Which bacteria causes relapsing fever
Definition
Borrelia
Term
Which bacteria causes relapsing fever
Definition
Borrelia
Term
Antibody Dependent Cell-mediated Cytotoxicity (ADCC)
Definition
Involves NK cells recognizing and killing antibody coated virally infected cells.
Term
Hyper-acute graft rejection
Definition
characterized by thrombotic occlusion of the graft vasculature in a very short time frame. Minutes to hours. Common with xenograft. Also common in allografts with mismatched ABO typing because those antigens are present on every cell.
Term
Direct recognition of allo antigens
Definition
Graft MHC similar enough to host that it can directly present to host TCR. Results in a large number of naive allo-reactive T-cells
Term
Indirect recognition of allo antigens
Definition
Hosts APCs take up graft cells and present antigen to T-cells as new peptides. "minor histocompatibility antigens."
Term
Acute rejection
Definition
7-10 days. CD4 and CD8 cells are the main players. CD8 cells do most the killing.
Term
Chronic rejection
Definition
6 months or more."rejection by occlusion" in that the insides of the vessel expand out with abnormal growth of the endothelial cells until the blood flow is so restricted that the tissue dies.
Term
Mechanism of cyclosporine and FK-506 in immunosupression
Definition
Blocks calcineurin which is needed by NFAT, a transcription factor that is responisble for IL-2 and other cytokine production.
Term
Mechanism of rapamycin in immunosuppression.
Definition
Blocks protein translation in proliferating cells
Term
Dr. Hills lecture
Definition
See previously made flash cards
Term
Nrf 2
Definition
major controller of redox homeostasis.
Term
DTH
Definition
Delayed typer hypersensitivity-The process of activating macrophages to kill intracellular pathogens, requires t-cell help. Is this the same as type IV hypersensitivity?
Term
Cytomegalovirus, Herpes virus mechanism of immune evasion
Definition
Inhibition of class I MHC presentation of cytosolic antigens
Term
Tumor specific transplantation antigens (TSTA)
Definition
antigens expressed on tumors that are tumor specific, their presence is recognized by T-cells and may sometimes stimulate tumor rejection responses. TSTAs are products of mutated normal cellular genes.
Term
Common tumor antigens
Definition
proteins or peptides with characteristics similar to TSTA that are present on the cell surface of many cancers derived from similar cell types. Common tumor antigens may be organ-specific markers, or may represent proteins encoded by a virus.
Term
tumor associated antigens (TAA)
Definition
Antigens that elicit a non-protective antibody response. Oncofetal antigens – antigens normally expressed only in development, e.g., carcinoembryonic antigen, alpha fetoprotein.
b. Altered glycoprotein and glycolipid antigens resulting from defects in complete glycosylation of proteins or lipids.
c. Tissue specific antigens – antigens specific for a particular tissue cell type.
Term
NFAT
Definition
Transcription factor that is ultimately blocked by Cylosporin and Fk56 binding to calcineurin
Term
Mixed Leukocyte reaction
Definition
If CD4 cells proliferate that means they have one MHC II in common or are very similar. If CD8 cells proliferate that means they have at least one MHC I in common or very similar
Term
Antibody Deficiency
Definition
Reccurent sinopulmonary infections and chronic diarrhea and should be screened with quantitative IgG, IgM and IgA and maybe IgG subclasses by nephelometry
Term
Complement defects
Definition
patients suffer blood stream and other infections with Streptococcus pneumoniae or Neisseria meningitides or gonorrhea.
Term
Phagocyte defects
Definition
Abscesses, boils, pneumonias and other tissue infections occur.
Term
T cell defects
Definition
Associated with severe viral, fungal and intracellular bacterial infections. Workup should consist of delayed hypersensitivity skin tests with candida, tetanus antigen and maybe PPD.
Term
NF-kappaB
Definition
becomes spontaneously activated under conditions of mild chronic oxidative stress. It controls many genes, including production of the pleiotropic inflammatory cytokines TNF, IL-6, IL-12, and IL-8. This transcription factor also controls the expression of numerous cellular adhesion molecules like ICAM-1 plus inducible nitric oxide synthase (iNOS) and cyclooxygenase II (COX-2).
Term
Sp1, AP-1, and GR
Definition
activities are inhibited under conditions of excessive oxidative stress.
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