HLA-A2-peptide (RMFPNAPYL) Recombinant mAb (S-4194) (PE Conjugate)

The HLA-A2-peptide (RMFPNAPYL) is a specific antigen complex presented by the major histocompatibility complex (MHC) class I molecule HLA-A*02 allele, which contains a high-affinity nine-amino-acid peptide derived from the melanoma-associated antigen MART-1/Melan-A (amino acids 27-35), with the sequence arginine-methionine-phenylalanine-proline-asparagine-alanine-proline-tyrosine-leucine (RMFPNAPYL). This complex holds milestone significance in tumor immunology, as HLA-A2 is the most common human leukocyte antigen haplotype worldwide (particularly highly expressed in Asian and Caucasian populations), and RMFPNAPYL, as the immunodominant epitope of MART-1/Melan-A, can be efficiently recognized by tumor-specific CD8+ cytotoxic T lymphocytes (CTLs). When this peptide binds to the groove of the HLA-A2 molecule on the surface of antigen-presenting cells or melanoma cells, the resulting pMHC complex directly activates CTLs expressing the corresponding T cell receptor (TCR), thereby triggering a targeted killing response against melanoma cells. Therefore, the HLA-A2-RMFPNAPYL tetramer is widely used as a specific probe in flow cytometry to detect, quantify, and isolate antigen-specific CD8+ T cells from the peripheral blood or tumor-infiltrating lymphocytes of melanoma patients, representing a core tool for assessing tumor immune responses and monitoring the efficacy of immunotherapy.