MHCclassIIantigen (45-57) [Homosapiens] is a peptide with the sequence H2N-Asp-Leu-Asp-Lys-Lys-Glu-Thr-Val-Trp-His-Leu-Glu- Glu-OH, MW= 1868.07. MHC (major histocompatibility complex) classII molecules are found only on antigen-presenting cells and l