Fig. 2.

Allogeneic mimotope peptide pools expand the alloreactive T-cell repertoire. (A) Peptide mimotope pools were designed with unrestricted amino acid use at the TCR contact points of P2, P3, P5, and P8 and canonical MHC anchor residues for either I-E^k (EKX) or I-E^p (EPX). (B) EKX and EPX pools were added at a final concentration of 200 μM to nonalloreactive primary CD4⁺ T-cell hybrids cultured with irradiated B6.K or B6.P splenocytes. Stimulation was assessed by measurement of IL-2 production by ELISA after 24 h of culture in three independent experiments for each hybrid. Data presented are mean ± SEM from one representative experiment. (C) Addition of peptide mimotope pools enabled response to I-E^k in 8/9 otherwise nonalloreactive T-cell hybrids and response to I-E^p by 4/8 nonalloreactive T-cell hybrids. Results are means of three independent experiments for each hybrid.