Design, Synthesis, and Preliminary Immunological Studies of MUC1-Based Antitumor Vaccines Adjuvanted with - and -FSL-1.

Fibroblast stimulating lipopeptide 1 (FSL-1) is the ligand of TLR2 and TLR6 and can be used as the vaccine adjuvant to prepare antitumor vaccines. However, FSL-1 is a stereoisomeric mixture that contains the stereoisomer and stereoisomer, and it is still unclear which stereoisomer has better adjuvant activities. In this work, we designed and synthesized MUC1-based antitumor vaccines adjuvanted with the stereoisomers -FSL-1 and -FSL-1, which were synthesized from the stereoisomeric building blocks -Fmoc-PamCys-OH and -Fmoc-PamCys-OH, respectively. Immunological evaluation indicated that both -FSL-1 and -FSL-1 can be used as adjuvants for the construction of MUC1-based antitumor vaccines, with -FSL-1 showing a better adjuvant effect than -FSL-1.