Term
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Definition
| lack of expression of HLA class I or II antigens on antigen presenting cells due to abnormal promoters of the genes for these components |
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Term
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Definition
| lack of IL-2 Receptor gammachain causing X-linked SCIDs which makes up as high as 50% of SCIDs |
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Term
| adenosine deaminase deficiency |
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Definition
| which makes up 30% of SCIDs due to the buildup of adenosine and deoxyadenosine which is toxic to T and B cells |
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Term
| nucleoside phosphorylase deficiency |
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Definition
| resulting in Nezelof’s syndrome, predominantly affecting T cells, and signal transduction defects resulting from ZAP 70 defects, Janus kinase 3 (JAK3) defects, and defects in the recombinase activating genes (Rac1 & Rac2). |
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Term
| Which immunodefiencies are considered scids |
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Definition
bare lymphocyte syndrome
X-linked SCIDs
adenosine deaminase deficiency
nucleoside phosphorylase deficiency |
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Term
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Definition
| monosomy/deletion of chromosome 22. Defect in 3rd and 4th pharyngeal pouches. Thymic hypoplasia, heart problems, parathyroids, thyroid defiency. Hypocalcemic tetany, low and unresponisve T cells, abnormal faces with microagnathia, cleft palate, short philtrum of the lip yielding a fishmouth appearance, and low set, malrotated ears with poor lobe formation. Thymus/marrow transplant can help. Overall less severe immunodefiency than SCIDs. |
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Term
| Chronic mucocutaneous candidias |
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Definition
| lymphocytes may not produce sufficient IL-2 or IFNgamma in response to candida, may be associated with multiple endocrine abnormalities including diabetes, Addison’s disease, hypoparathyroidism. |
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Term
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Definition
| Lack WASp important in Antigen presentation. Eczema, small bad platelettes, T cell and some B cell deficiency. Poor polysacharide antibodies. May develop lymphomas later in life, often experience bruising. Bone marrow/ stem cell transplant may be curative. |
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Term
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Definition
| Autosomal recessive, results in ocular and cutaneous telangiectasia, absent IgA (70%), low IgG2 (50%), low IgE (80%) and decreased T cell function. Lack of DNA repair, mothers may develop breast cancer. |
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Term
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Definition
terminal cysteines are adjacent CC chemokines, MIP-1alpha.
Separated by one amino acid CXC chemokines, IL8 |
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Term
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Definition
| Act on monocytes, lymphocytes, and eosinophils |
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Term
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Definition
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Term
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Definition
| Produced by bacteria. Phagocytic cells possess a chemotactic receptor for fMLP, which results in rapid recruitment to sites of infection. |
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Term
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Definition
| Recognize unique patterns on foreign cells, pathogen associated molecular patterns (PAMPS). function through signaling and activation of cells. Do not promote phagocytosis. |
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Term
| Other cell-associated pattern recognition molecules |
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Definition
C-type lectins (mannose receptor),
CD36 (scavenger receptor),
Nods/NALP cytoplasmic receptors (bacterial peptidoglycan and others),
fMLP receptor |
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Term
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Definition
| subset of lymphocytes that kill virus-infected cells and secrete cytokines, mainly IFNgamma. Inhibited by MHC I, activated by IL-15 and IL-12 |
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Term
| Soluble pattern recognition receptors |
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Definition
Mannose-binding lectin (MBL), binds carbohydrates with terminal mannose and fructose (microbial), activates lectin pathway of complement.
C reactive protein (CRP), opsonizes microbes, activates complement |
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Term
| Cytokines of innate immunity |
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Definition
| Type I interferons, IL-1, and TNF. These cytokines are strongly induced by toll like receptor signaling in macrophages. |
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Term
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Definition
| made by PMNs and epithelial cells, fragments are anti-microbial |
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Term
| Intraepithelial T lymphocytes |
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Definition
| possess gammadelta T cell receptors of limited diversity, and recognize common microbial structures such as lipids, presented by CD1 |
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Term
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Definition
| have surface Ig of limited diversity that recognize polysaccharides and lipid antigens found on many different bacteria. Produce “natural IgM antibodies”. |
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Term
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Definition
| 7 transmembrane spanning, G-protein linked receptors |
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Term
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Definition
| fast acting chemoattractants |
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Term
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Definition
|
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Term
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Definition
|
|
Term
| Cytoplasmic NLRs (like TLRs) |
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
| lipoproteins, peptidoglycan & lipotechoic acid |
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Term
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Definition
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Term
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Definition
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Term
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Definition
| C3b bound to microbe then binds factor B. Factor D cleaves it to C3bBb which is the C3 convertase. Properdin stabilizes this hybrid. C5 convertase: C3bBbC3b |
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Term
| Lectin Binding protein pathway |
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Definition
| MBL is very similar to C1q, and in fact can bind and active the C1r, C1s proteins. However, there are a second set of proteases, MASP proteins (mannose-binding protein associated serine protease) which function the same as C1r/C1s (related genes). Basically the same as the classical pathway but with a different initiation |
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Term
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Definition
induction controlled by Th1 cytokines, interferon gamma and TNF-a. blocks T-cell function by interfering with the IL-2 signaling pathway.
Under low L-Arginine conditions, NOS2 generates NO and superoxide which combines to make peroxynitrite, a highly reactive oxidizing agent that nitrosylates tyrosine residues on virtually all proteins. This induces apoptosis and inhibits phosphorylation |
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Term
| Arginase (as expressed by immunological cells) |
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Definition
ARG-1 is induced by Th2 cytokines (IL-4, IL-13, TGF)
ARG-2 is induced by LPS, cAMP and bacterial infection.
Arginase depletes microenvironmental L-Arginine availability.
Localized L-Arginine starvation will control growth of particular cell types, including T cells.
Arginine depletion suppresses zeta chain expression (T cells and NK cells, part of TLRs) |
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Term
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Definition
Elevations in NOS2 activities have been reported to inhibit ARG-1 expression and ARG-1 expression has been reported to inhibit NOS2.
Sometimes, however, both become expressed in the same cell. This is bad for cell viability and host immune responses, etc. |
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Term
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Definition
| to arise from a blockage in the terminal differentiation of myeloid cell precursors. Increased numbers from stress, trauma, cancer, sepsis and aging. strongly immunosuppressive, employing mechanisms involving arginine metabolism to mediate their immunoregulatory processes (generation of NO or arginine depletion by ARG-1). Gr-1 and CD11b positive and are immature morphologically |
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Term
| How can respiratory burst be detected |
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Definition
| Respiratory burst generation of superoxide can be determined by determining NBT dye reduction or, more recently, by the conversion of dihydrorhodamine to fluorescent rhodamine by stimulated PMNs |
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Term
| How is myeloperoxidase detected |
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Definition
| Myeloperoxidase can be detected and semiquantitated by simple hematologic stain. |
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Term
| How are integrin and selectin defiencies detected |
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Definition
| Flow cytometry with specific monoclonal anitbodies |
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Term
| PMN cell surface integrins |
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Definition
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Term
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Definition
| Sialyl-Lewis X. Requires fucosylation. |
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Term
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Definition
| Autosomal defect of beta chain in several different integrin molecules on PMNs and Macs. No diapedesing or iC3b opsonization. High WBC/PMN count but cutaneous or perirectal abscesses with little or no PMN infiltration. delayed separation of the umbilical cord. Bone marrow/stem cell transplant can be lifesaving. |
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Term
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Definition
| defect in fucosylation. Patients also present w neurologic and facial abnormalities. Very rare. |
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Term
| Phagocyte chemotactic disorders |
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Definition
| . Defects in PMN chemotaxis have been described with severe bacterial and viral infections such as influenza, in burns due to over release of inflammatory mediators, in diabetes due to glucose induced auto oxidation, in rheumatoid arthritis due to ingestion of immune complexes, and in malnutrition and uremia. Also infants and premies. |
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Term
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Definition
| hyperimmunoglobulinemia E. Poor PMN chemotaxis due to little IFNgamma. is associated with severe eczema, recurrent staphylococcal abscesses, chronic mucocutaneous candidiasis, abnormal faces with broad bridge and base of the nose, prominent forehead, doughy consistency to the skin, and bone fractures. Defect is in STAT3. Autosomal dominant with incomplete penetrance. |
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Term
| Chronic granulomatous disease |
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Definition
| Can be x-linked or autosomal recessive. infections associated with catalase positive organisms in which granuloma develop at the site of infection. The disorder can be diagnosed with a neutrophil oxidative burst assay (DHR) showing no increase in fluorescence (X-linked) or only intermediate fluorescence (autosomal recessive) and confirmed by a Western blot analysis of the involved components. Treatment with IFN can reduce serious infection by 70% especially those due to aspergillus. |
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Term
| Myeloperoxidase deficiency |
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Definition
| can be familial resulting in chronic mucocutaneous candidiasis and abscesses or acquired with monomyelocytic leukemia, where it may be asymptomatic or associated with abscesses. Treatment is symptomatic at present. |
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Term
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Definition
| defect in granule membrane fusion resulting in poor PMN chemotaxis and deficiency in myeloperoxidase leading to delayed intracellular killing by phagocytes. Also leads to oculocutaneous albinism. |
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Term
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Definition
| C1q binds to antibody/membrane and allows autoactivation of C1r which activates C1s. Active C1s cleaves C2 and C4. C4b forms a thioester bond to microbe and associates with C2b. C3 convertase = C4b2b which activates C3, Amplification occurs and many C3b are deposited on microbe surface. C5 convertase = C4b2b3b which can activate C5. |
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Term
|
Definition
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Term
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Definition
| C3 randomly hydrolyzes and C3b binds microbe surface. Factor D cleaves serum Factor B which binds C3b and forms Alternate C3 convertase = C3bBb. Properdin stabilizes this hybrid. C5 convertase = C3bBbC3b |
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Term
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Definition
| Like the classical pathway except MBL = C1q and MASP proteases = C1r and C1s. |
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Term
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Definition
| C5b is not bound to membrane like C3 and C4, instead remains associated with membrane or becomes fluid phase. C5b binds C6 then C7. Opens hydrophobic site on C7 which allows a membrane insertion. C8 binds and inserts. 10-12 C9's are recruited which create a 100 A hole in the membrane. |
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Term
| Receptors of the complement pathway |
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Definition
CR1 is a major receptor of about 200,000 daltons : Important receptor to phagocytosis of C3 and C4 bound complexes.
CR2, on B cells and FDC's: more important as B cell activating receptor:
CR3, is an integrin that binds C3 and aids in phagocytosis: |
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Term
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Definition
| Binds Active C1 and removes C1r and C1s |
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Term
| DAF (decay acceleration factor) |
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Definition
| Displaces Bb from C3b and C2b from C4b = disrupts C3 convertase |
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Term
| MCP (membrane co-factor protein) |
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Definition
| Promotes C3 and C4 inactivation by factor I |
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Term
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Definition
| Cofactor for I. Breaks up C3 convertase |
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Term
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Definition
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Term
|
Definition
| Serine protease that cleaves C3b or C4b thus inactivating them. Uses other cofactors |
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Term
|
Definition
| Binds C3b displacing Bb. Cofactor for I |
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Term
|
Definition
| Binds C4b displacing C2b. Cofactor for I |
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