Figure 5. DCs generated in the presence of minocycline are deficient in allogeneic T cell priming.

A. Immature DCs generated from C57BL/6 mouse BM cells with (Mino-DCs) or without (Ctrl-DCs) minocycline were stimulated with LPS for 24 h for maturation, and then co-cultured for three days with CD4⁺ T cells isolated from the spleens of BALB/c mice at the indicated ratios. DNA synthesis was measured by the incorporation [³H]-thymidine added for the final 18 h of culture. B. Mino-DCs and Ctrl-DCs generated in vitro were transferred to BALB/c mice (1 × 10⁶/mouse). Ten days later, T cells were isolated from the spleens and re-stimulated with normal (C57BL/6 mouse BM-generated) DCs at the indicated ratios. DNA synthesis was measured as above. DCs generated from BALB/c mouse BM ells served as a syngeneic control (Syn-DC). The data are presented as the mean ± SD of three independent experiments. C. C57BL/6 mice were injected i.p. with GM-CSF and minocycline (Mino-DC) or GM-CSF (Ctrl-DC) for 6 days. On day-7, CD11c⁺ cells were isolated from the spleens and transferred to BALB/c mice (1 × 10⁶/mouse). DCs generated from BALB/c mouse BM cells served as a syngeneic control (Syn-DC). After 10 days, total T cells were isolated from the spleens and co-cultured with normal C57BL/6 BM-derived DCs. DNA synthesis was measured as above. The data are presented as the mean ± SD of three independent experiments; *P < 0.05, **P < 0.01 compared with the Ctrl-DC group.