MHC Antibodies

The major histocompatibility complex is an area in which intracellular antigens are represented on the outer surface of the cell. MHC genes code for these specific proteins. These antigens are responsible for major immune responses such as the recognition of foreign substances. These proteins are found in all upper level vertebrates. There are 3 major classes of histocompatibility complexes: Class I, Class II and Class III. The molecules in class I and II belong to a group called immunoglobulin supergenes which is comprised of immunoglobulins and T- Cell receptors. Class I MHC molecules are found widely across all cell membranes. Class II molecules are only found in immune system cells such as macrophages and lymphocytes. The Class III MHC molecules include only compliment components. In humans, the MH complex is also known as the human leukocyte antigen or HLA system. The genetic code for these genes is found on the human chromosome 6. The genes for MHC proteins are widely varied in the human population and thus allows for many different tissue types. This is important when studying organ and tissue transplants. Antigens bind to MHC antibodies which can affect the response of the immune system and are quite commonly responsible for post-transplant rejections of organs and tissues.

The anti- CD41b antibody targets a receptor that recognizes a certain sequence on a large number of ligands. Following binding and activation, it will facilitate platelet aggregation and essentially plug ruptured surfaces on cells. Anti- RFX5 antibody will bind to a protein responsible for activating transcription from a class II MHC promoter, mediating cooperative binding, and recognizing x- boxes. Defects in RFX5 or anti-RFX5 antibody cause bare lymphocyte syndrome type 2 which is a severe immunodeficiency disease characterized by absent T- cell response and diminished antibody production.