NorthWest Biotherapeutics Inc (NWBO)

[supersteve13]

Think of MHC 1 and 2 proteins as flagpoles that are made inside antigen presenting cells like DCs for this example. Self and foreign antigens (peptides) are taken up via pinocytosis etc after destruction of tumor cells, virus infected cells etc. Then these peptides are loaded as “flags” onto the MHC 1 or 2 flagpoles inside the DC, and then sent to the cell surface for display to T cells (primarily). The T cells then recognize (or not) the “flag” as self or foreign- but the flag must be in the context of either MHC 1 or 2 (I.e. on the flagpole) for the T cell to “see” the flag. MHC 1 and 2 display different types of peptides, with 2 displaying longer ones than 1, among other differences. Most cells can display MHC 1 with associated flags, but MHC 2 is largely restricted to professional APCs.

There is no guarantee that a given peptide sequence can be displayed- it depends on the individuals HLA/ MHC haplotype inherited from parents.