Major histocompatibility antigens

Since all members of this family of RNA phages have homologous coat proteins, their subunits are expected to have the same three-dimensional structure. It remains to be seen if the MS2 fold is also present in any other unrelated viruses. The fold is so far unique for the MS2 subunit, but similar structures have been observed in other proteins such as the major histocompatibility antigen, HLA, which was discussed in Chapter 15. 

Alloimmunity is the immune response mounted by a host on the basis of differences in major histocompatibility antigens expressed on the surface of a donor cell from the same species as the host. 

Autoimmune Disease. Figure 2 Generation of autoreactivity. APC, antigen presenting cell IFN, interferon LPS, lipopolysaccharide MHC, major histocompatibility complex T, T-lymphocyte TCR, Tcell (antigen) receptor TLR, toll like receptors. For details see text. 

The human leucocyte antigen (HLA) system is the general name of a group of genes in the human major histocompatibility complex (MHC) region on human chromosome 6 (mouse chromosome 17) that encodes the cell-surface antigen-presenting proteins. 

York lA, Goldberg AL, Mo XY, Rock KL Proteolysis 73 and class I major histocompatibility complex antigen presentation. Immunol Rev 1999 172 49-66. 

Ia+ Murine class II major histocompatibility complex antigen IB4 Anti-CD 18 monoclonal antibody IBD Inflammatory bowel disease IBMX 3-isobutyl-l-methylxanthine IBS Inflammatory bowel syndrome iC3 Inactivated C3 iC4 Inactivated C4 IC50 Concentration producing 50% inhibition... 

An unknown antigen presented by the major histocompatibility complex (MHC) class II molecules causes T cells to become autoreactive (Fig. 26-1). Once activated, T cells penetrate the... 

Family history of RA. Genetic studies demonstrate a strong correlation between RA and the presence of major histocompatibility complex class II human leukocyte antigens (HLA), specifically HLA-DR1 and HLA-DR4.4,5 HLA is a molecule associated with the presentation of antigens to T lymphocytes. 

Human leukocyte antigens (HLA) Groups of genes found on the major histocompatibility complex, which contain cell-surface antigen-presenting proteins. The body uses HLA to distinguish between self-cells and non-self-cells. 

The T-lymphocyte receptor (TCR) is involved in detection of foreign antigens, presented together with the major histocompatibility complex (MHC). Subsequendy, it regulates the clonal expansion of T cells. 

Kumar, V., Bhardwaj, V., Soares, L., Alexander, J., Sette, A. and Sercaz, E. (1995) Major histocompatibility complex binding affinity of an antigenic determinant is crucial for the differential secretion of interleukin 4/5 or interferon-y by T cells. Proceedings of the National Academy of Sciences USA 92, 9510-9514. 

Immunoglobulins (Igs) can activate the complement system, which amplifies the immune response by enhancing chemotaxis, phagocytosis, and release of lymphokines by mononuclear cells that are then presented to T lymphocytes. The processed antigen is recognized by the major histocompatibility complex proteins on the lymphocyte surface, resulting in activation of T and B cells. 

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