II Antigens

The class II cytokine receptor family includes receptors for interferon a/P (lEN a/P) and y (lENy) and IL-10. lEN-y immunoreactivity has been found in neurons in the hypothalamus, cerebral cortex, mammilary nuclei, and dorsal tegmentum. Astrocytes and microglia in vitro can be stimulated to express class II histocompatibiHty complex (MHC-II) antigens by lEN-y, which may be involved in the presentation of antigen to T-ceUs by astrocytes. Thus lEN-y may be critical in CNS-immune function and dysfunction especially in regard to neuronal and gHal apoptotic processes. 

Suda T, Sato A, Sugiura W, Chida K (1995) Induction of MHC class II antigens on rat bronchial epithelial cells by interferon-gamma and its effect on antigen presentation. Lung 173(2) 127-137. 

Some of the reasons for the return are as follows (i) new breeding grounds for the insects that are vectors for some pathogens (ii) antigenic drift in viruses and bacteria (iii) resistance to antibiotics (iv) a decrease in the effectiveness of the immune system due to the presence of other more chronic infections, poor nutrition or stress (v) expansion of air travel. 

II antigens [133,134]. Moreover, they inhibit the secretion of the complement pathway proteins C3 and factor B [135]. 

Finally, in this brief overview of lymphocyte defects, mention should be made of mutations affecting major histocompatibility-complex (MHC) Class II molecules. These mutations affect a multiprotein transcription factor complex that regulates the expression of MHC Class II molecules (121). Affected patients have undetectable levels of MHC Class II antigens HLA-DP, DQ, and DR on the surface of monocytes and B cells. Lack of these antigen-presenting molecules leads to impaired immune response. Affected individuals have moderate lymphopenia with a severely reduced number of CD4+ T cells and normal or increased numbers of CD8+ T cells. Since MHC molecules in the thymic epithelium play a key role in positive and negative selection of primitive T cells, selection of competent T cells is also affected in the absence of MHC Class II antigens. 

B. Effect of Nitric Oxide Synthesis on RAW 264.7 Class II Antigen Expression and Antigen Presenting Cell Function... 

Mendlovic, F., Tarrab-Hazdai, R., Puri, J. and Arnon, R. (1 989) Genetic control of immune response to a purified Schistosoma mansoni antigen. I. Effect of MHC class II antigens on the cellular, humoral and protective responses. Parasite Immunology 11, 667-682. 

Fig. 4. Glycan arrays are used to characterize the antibody profiles of vaccinated animals (Glycan array I) and to scan for asialo-orosomucoid (ASOR)-specific immunological probes (Glycan array II). Antigen preparations spotted on each glycan array and their array location are summarized in Supplemental Tables SI and S2 of reference (18) (available at the Physiological Genomics Web site).

NE also inhibits the I FNy-induced major histocompatibility (MHC) class II antigen expression in rat astrocytes, which is reduced by propranolol, but not by phentolamine or propranolol, suggesting that the effect of NE might be mediated through (32-adrenoreceptors (Frohman et al., 1988). 

NE also influences the expression of other genes involved in the inflammatory response in the brain, such as MHC class II antigen and ICAM-1. More specifically, NE has opposite effects on these gene products depending on the cell type, like reducing the expression of MHC class II in glial cells, while enhancing MHC class II in IFNy-stimulated bovine brain endothelial cells. On the other hand, NE reduces the expression of ICAM in both astrocytes and brain endothelial cells (Feinstein et al., 2002). 

Villadangos JA, Bryant RA, Deussing J, Driessen C, Lennon-Dumenil AM, Riese RJ, Roth W, Saftig P, Shi GP, Chapman HA, Peters C, Ploegh HL (1999) Proteases involved in MHC class II antigen presentation. Immunol Rev 172 109-120... 

Langeland, T. 1982a. A clinical and immunological study of allergy to hen s egg white. II. Antigens in hen s egg white studied by crossed immunoelectrophoresis (CIE). Allergy 37 323-333. 

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