FIGURE 5.

HLA-DR4 transgenics immunized with LF peptide pools comprising domain I of the protein demonstrate CD4+ T cell cryptic epitopes. HLA-DR4 transgenic mice were immunized with pools of non-overlapping LF peptides comprising domain I (A–D), and draining lymph node cells were cultured in an IFNγ specific ELISpot plate with 25 μg/ml of each individual peptide from the immunizing pool. Results are given as the number of spots above background (ΔSFC)/10⁶ PBMCs with mean ± SD (n = 5 mice for each column).