Histocompatibility antigen proteins

Two groups have independently suggested that the peptide-binding domain of the stress-70 proteins may be similar in structure to the peptide-binding domain of the histocompatibility antigen proteins (HLAs) (Flajnik et al., 1991 Rippmann et al., 1991). This suggestion is... 

Doyle A, Martin WJ, Funa K, Gazdar A, Carney D, Martin SE, Linnoila 1, Cuttitta F, Mulshine J, Bimn P Markedly decreased expression of class 1 histocompatibility antigens, protein, and mRNA in human small-cell lung cancer. J Exp Med 1985 161 1135-1151. 

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. 

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. 

Robert, J., et al., Minor histocompatibility antigen-restricted CD8 T-cell responses elicited by heat shock proteins, J. Immunol., 168, 1697, 2002. 

T. H. Watts, H. E. Gaub, and H. M. McConnell, T-cell-mediated association of peptide antigen and major histocompatibility complex protein detected by energy transfer in an evanescent wave-field, Nature 320, 176-179 (1986). 

They recognise small peptide antigens that mnst be bound to a specific protein, the major histocompatibility complex protein (MHC) (see below). 

Eisen, H.N., Sykulev, Y., Tsomides, T.J. (1996). Antigen-specific T-cell receptors and their reactions with complexes formed by peptides with major histocompatibility complex proteins. Adv. Prot. Chem. 49,1-56. 

Major-Histocompatibility-Complex Proteins Present Peptide Antigens on Cell Surfaces for Recognition by T-Cell Receptors... 

Mr 11,800) globular protein located on the surface of virtually all nucleated cells. It is closely related to the class I histocompatibility antigens which consist of a heavy, variable chain and a hght chain that hinds to the heavy chain domain nearest to the cell membrane. The light chain consists of the molecule. Due to its... 

It has been shown that a number of peptides linked to the N-terminal end of the diphtheria toxin A-fragment are translocated to the cytosol (Stenmark etai, 1991, Stenmark etal., 1992 Ariansen efal., 1993). It is an interesting question to what extent such peptides can subsequently be presented by class I major histocompatibility antigens. If this is the case, fusion proteins of viral or cancer-related peptides and enzymatically inactive mutants of diphtheria toxin could be used for vaccination purposes to expand desired populations of cytotoxic CD T-lymphocytes. 

Major-Histocompatibility-Complex Proteins Present Peptide Antigens on Cell Surfaces for Recognition by T-Cell Receptors Intracellular pathogens such as viruses and mycobacteria cannot be easily detected. Intracellular proteins are constantly being cut into... 

There are several examples of parts of membrane proteins determined crystallographically. Here, a protein anchored in the membrane is clipped to provide just the hydrophilic domain for crystallisation. These studies were of cytochrome b5 (Mathews, Argos and Levine 1972), haemagglutinin (Wilson etal 1981) and neuraminidase (Varghese, Laver and Colman 1983) from influenza virus and the human class I histocompatibility antigen, HLA-A2 (Bjorkman et al 1987). 

The most familiar of the recognition proteins are antibodies or immunoglobulins. Another class of recognition molecules consists of the proteins called T-cell receptors but less is known of their properties and structure. A third class of proteins with a vital role in immune recognition is those in the major histocompatibility complex (MHC). The MHC proteins were discovered in tissue-grafting experiments. The structure of the major histocompatibility antigen has been determined by Bjorkman et al (1987). 

Major-Histocompatibility-Complex Proteins Present Peptide Antigens... 

MAJOR-HISTOCOMPATIBILITY-COMPLEX PROTEINS PRESENT PEPTIDE ANTIGENS ON CELL SURFACES FOR RECOGNITION BY T-CELL RECEPTORS... 

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