Figure 3.
Characteristics of induced PLAC1-specific CD4 helper T cells. (A) Estimation of the peptide dose-responses of PLAC131-50-specific CD4 T cells (T4, Y6 and H9). These T cells were co-cultured with autologous PBMCs pulsed with various concentrations of PLAC131-50 peptide for 48 h. Supernatants were harvested and the secretion of GM-CSF was measured by ELISA. Points, mean of duplicate measurements; error bars, SD. (B) Determination of the HLA restriction of PLAC131-50-specific CD4 T cells. The response of T cells co-cultured with autologous PBMCs pulsed with PLAC131-50 peptide (3 μg/ml) was evaluated in the presence of anti-HLA-DR mAb L243 or anti-HLA class I mAb W6/32 (negative control). (C) Detailed determination of which HLA-DR molecules are responsible for PLAC131-50 peptide presentation. The response of CD4 T cells to PLAC131-50 peptide was measured using peptide-pulsed (3 μg/ml) L-cells transfected with individual HLA-DR alleles as APCs. In B and C, supernatants were harvested after 48 h and GM-CSF secretion was measured by ELISA. Columns, mean of triplicate measurements; error bars, SD. Statistical significance was assessed using an unpaired Student’s t-test (*p< .05)