2L5L9V-GP2

2L5L9V-GP2 (also known as SPA-13) is a modified HER2/neu-derived peptide vaccine candidate. It is a synthetic 9-amino-acid peptide variant of the GP2 peptide (IISAVVGIL, corresponding to residues 654–662 of the HER2/neu protein), containing amino acid substitutions at positions 2 (Leucine), 5 (Leucine), and 9 (Valine) designed to increase its binding affinity to HLA-A2 and HLA-A3 MHC Class I molecules. Developed by researchers from institutions including the Uniformed Services University of the Health Sciences and the M.D. Anderson Cancer Center, 2L5L9V-GP2 was evaluated preclinically for its ability to stimulate CD8+ cytotoxic T lymphocytes (CTLs) in breast cancer patients. However, despite computer modeling predicting higher binding affinity, preclinical studies demonstrated that 2L5L9V-GP2 elicited lower CTL recognition and functional responses compared to both the wild-type GP2 peptide and another variant, SPA-12 (2L9V-GP2). Consequently, development of this specific variant was not pursued further.

Other names

ILSALLGIVmodified HER2/neu peptide vaccine (2L5L9V-GP2)SPA-13(2L5L9V-GP2)