T cells from ipsilateral cervical LNs and spleens of (NACOMe)
2- or saline-treated mice that had received B10.D2 corneal allografts were purified 1 or 2 weeks after transplantation. Purified T cells from BALB/c mice injected subcutaneously in the neck with 1 × 10
7 B10.D2 splenocytes 1 week earlier served as the positive control. T cells (2.5 × 10
5) were cocultured for 24 to 72 hours with 2.5 × 10
5 x-irradiated B10.D2 or DBA/2 splenocytes in 96-well plates, and supernatants were collected to measure cytokine secretion. T-cell proliferation was analyzed after 5 days. At 1 week after transplantation, T cells from mice injected with (NACOMe)
2 or saline manifested neither positive proliferation nor cytokine secretion (data not shown), but at 2 weeks after transplantation, T cells from these mice exhibited increased proliferative responses
(Fig. 2A) and cytokine production
(Fig. 2B) . DBA/2 splenocyte-stimulation of T cells from saline-treated, (NACOMe)
2-treated, and positive control mice did not induce proliferation and cytokine secretion. On exposure to B10.D2 splenocytes, T cells from saline-treated grafted (
n = 6) and positive control (
n = 4) mice proliferated and secreted significant amounts of IFN-γ, but not IL-4 and IL-10. In contrast, T cells from (NACOMe)
2-treated graft-recipient mice (
n = 10) showed less proliferation and less secretion of IFN-γ. Our results indicate that (NACOMe)
2 treatment suppressed the Th1 alloresponse in corneal graft recipients.