Antigen presenting proteins

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. 

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. 

Antigen Presenting Proteins that display peptide Human leukocyte antigens Figures 1, 2,... 

It is evident from the examples describing immunoglobulin and TcR structures that only a few residues of each protein molecule are crucial for the recognition process. The remainder of the structure of the molecule, the receptor, or the antigen-presenting protein is involved in other functions, including localization by other cell surface proteins. 

In contrast to the conventional CD4+ and CD8+ T cells of the immune system that recognize specific peptide antigens bonnd to major histocompatibility complex class II or class I antigen presenting proteins, respectively (131-133), invariant natural killer T cells recognize glycolipid antigens presented by histocompatibility complex... 

Vanbuskirk, A., Crump, B.L., Margoliash, E., Pierce, S.K. (1989). A peptide binding protein having a role in antigen presentation is a member ofthehsp70 heat shock family.). Exp. Med. 170,1799-1809. 

Figure 2 Immobilized antigen ELISA format. Antigen is immobilized to a solid phase by passive adsorption. Following removal of unbound antigen, analyte (free H) and antigen (H-protein) compete for a fixed number of primary antibody (Y) binding sites. Unbound materials are removed (dotted line). Secondary antibody-enzyme conjugate (Y-E) is added to bind to primary antibody followed by another wash step. Substrate (A) for the enzyme is added to detect the bound enzyme. The amount of colored product ( ) detected is inversely proportional to the amount of analyte present...

Antigen-presenting cells recognize complex three-dimensional protein molecules of at least 1000 daltons (Da) in size. Most drugs are much smaller than this and cannot be recognized on their own. Only proteins such as insulin or exogenous sera are identified and their peptides presented directly to T cells. 

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