Inhibition of ICAM-1/LFA-1-mediated heterotypic T-cell adhesion to epithelial cells: design of ICAM-1 cyclic peptides

In this work, we have designed cyclic peptides (cIBL, cIBR, cIBC, CH4 and CH7) derived from the parent IB peptide (ICAM-1 1–21) that are inhibitors of ICAM-1/LFA-1-mediated T-cell adhesion to Caco-2 cell monolayers. Cyclic peptide cIBR has the best activity of any of the peptides evaluated. The active ICAM-1 peptides have a common Pro-Arg-Gly sequence that may be important for binding to LFA-1. Cyclic peptides cIBR and CH7 were found to inhibit adhesion of T-cells to Caco-2 cell monolayers.