FIGURE 3.

The concentration-dependent effect of Pyr on CD4⁺ T-cell activation. A, for analysis of protein aggregation, 5.0 μg of native OVA, OVA modified with pyrraline at different molecular ratio by incubation with 3-DG at 70 °C for 1, 2, or 4 h (see Table 2), or OVA incubated at 70 °C for 4 h without 3-DG, a control for Pyr-OVA, were applied to SDS-PAGE with 4 to 20% acrylamide gradient in nonreducing condition. Separated proteins were quantified by densitometry. MW, molecular weight. B, CD4⁺ T-cells isolated from OT-II mice were co-cultured with BMDCs in the presence of 2 or 20 μg/ml of OVA samples. Concentrations of IL-2 in culture supernatants after 24 h were measured by ELISA. The data are representative of two independent experiments.