I-2190A is a potent immunosuppressive drug for vascularized heart transplantation in rats

The effect of a new immunosuppressant-I-2190A was tested in a rodent heart allograft model. Grafts were transplanted to recipients heterotopically. There were 5 groups: group 1 received no immunosuppressive agents; group 2 was given CsA (2.0 mg/kg, i.p.); group 3 was administered I-2190A (0.1 mg/kg, i.p.) in carboxymethyl cellulose (CMC); group 4 received injection of I-2190A (0.5 mg/kg, i.p. in CMC); group 5 received the combination treatment of I-2190A (0.1 mg/kg) and CsA (2.0 mg/kg). Immunosuppressants were discontinued 14 days after operation. No statistically significant difference in grafts median survival time (MST) was found between group 2 (9.5 days) and group 1 (9 days). The MSTs of grafts in group 3 (22 days, P < 0.05), group 4 (> 100 days, P < 0.01) and group 5 (> 100 days, P < 0.01) were significantly prolonged compared with control group 1 (9 days). Our results suggest that I-2190A is a potent immunosuppressant able to significantly prolong heart allograft survival in rats after a short time treatment, Low-dose I-2190A could potentiate the effect of sub-therapeutic dose of CsA as well.