The Class I MHC molecules process endogenous(intracellular) peptides/antigens whereas the Class II process exogenous(extracellular) peptides/antigens.
The Class I molecules are assembled and located in the ER whereas the Class II are assembled in the ER but located in the endosomes.
When extracellular peptides are taken into the cell via receptor mediated endocytosis or phagocytosis, they will be transported into the endosomes and get degraded. This will enable the peptide generated to be loaded onto the Class II molecules.
For Class I, when a bacteria or virus infect a cell, they will replicate and produce proteins. These proteins will be ubiquitinated and degraded by the proteasome. This smaller peptides can then be transported into the ER via the TAP transporters, that are complexed with the Class I molecules, to be loaded onto the Class I molecules.
T cell receptors bind to MHC class 1 molecules. MHC class 1 molecules bind to peptides (self or foreign) and present it to the cell's membrane. The job of a T cell is to decide what is presented on the MHC class 1 cell whether to leave it alone or to activate to destroy it because it is non-self.
The answer previously here about MHC referring to mice and HLA referring to humans is catagorically untrue! HLA and MHC are in fact the same, so HLA class 1 = MHC class 1. Same goes for class 2.
MHC proteins express antigens on a cell surface for T cells to identify whether the antigens presented are self or foreign. There are two classes MHC I and MHC II. They differ in which cells they require to activate depending on the pathogen present.
MHC restriction refers to the requirement that T cells recognize antigens only when they are presented by Major Histocompatibility Complex (MHC) molecules. T cells, particularly CD4+ helper and CD8+ cytotoxic T cells, can only bind to specific peptides displayed on the surface of antigen-presenting cells in conjunction with their corresponding MHC class (Class I for CD8+ and Class II for CD4+). This mechanism ensures that T cells can identify and respond to infected or abnormal cells while maintaining self-tolerance. MHC restriction is crucial for the adaptive immune response and plays a significant role in organ transplantation and autoimmune diseases.
MHC (Major Histocompatibility Complex) is a region of genes that codes for cell surface proteins involved in immune recognition, including the HLA (Human Leukocyte Antigen) genes. HLA specifically refers to the proteins encoded by MHC genes in humans, while MHC is a broader term that encompasses similar gene regions in other species.
Yes, neurons can express MHC class I receptors on their surface under certain conditions. This expression is important for immune surveillance and can contribute to neurological disorders when dysregulated.
Class ll
Class I MHC molecules present antigens to cytotoxic T-cells (which are CD3+CD8+).
Each individual has a unique MHC profile Clinically important MHC are HLA(human leukocyte antigens) -A, -B -DR -expression of a particular combination of MHC genes Class I - are located on all nucleated cells Class II - are located on macrophages, dendritic cells, B cells.
Well, there is not really a short answer for it: 1) there are 2 class of MHC: HLA/MHC-I: binds to CD8 T cells HLA/MHC-II: binds to CD4 T cells A physician has to check for a good match of the MHC subtypes in a transplation between graft and host. A good match reduces the risk of immune complications after the transplantation.
Presented by APCs as MHC-exogenous peptide complex
MHC genes code for the Major Histocompatibility Complex proteins. These proteins are essential for the immune system to distinguish self from non-self antigens and help in the presentation of antigens to T cells. The MHC genes are highly polymorphic, giving rise to diverse MHC proteins that enable recognition of a wide range of pathogens.