Figure 6.

Transduced GILT KO B cells could not induce tolerance to disulfide bond-containing Ag HEL. A, LPS-activated GILT KO or WT C57BL/6 B cells were transduced with HEL-IgG or OVA-IgG as a mock control. Normal C57BL/6 recipients were injected i.p. with 10⁷ transduced B cells. On day 7 postinjection, animals were immunized in a hind footpad and the base of tail with 25 μg of HEL protein emulsified in CFA. Two weeks postimmunization, animals were sacrificed and draining LNs were removed. T cell proliferation to HEL protein was determined by [³H]thymidine incorporation. Values represent mean Δcpm ± SE for four animals. The background [³H]thymidine incorporation was in the range of 13,000–20,000. Data are representative of four independent experiments. *, p < 0.05. B, Animals were treated as described in Fig. 6A. Two weeks postimmunization, sera were assayed by the endpoint ELISA method. The Ab titer was determined by the highest dilution of samples, with an OD₄₅₀ greater than the negative control (undiluted mouse serum). The result is shown as the mean ± SE of Ab titers. Data are representative of four independent experiments.