Infusion of donor spleen cells and rejection in liver transplant recipients

Intact or inactivated donor lymphoid cells have been found to downregulate the alloimmune response in a number of experimental models. We conducted a randomized, prospective, double blind, and placebo-controlled trial to determine whether heat-treated donor spleen cells would affect early rejection after liver transplantation. Donor spleen was obtained during organ procurement for 40 patients undergoing liver transplantation. All patients were treated with cyclosporine, azathioprine and steroids. The patients were randomized after surgery to receive either heat-treated (45°C for 1 h) spleen cells or placebo. Patients underwent protocol biopsies at 1 wk, 4 and 12 months, or as needed. Biopsies were reviewed in a blind fashion and scored according to the Banff consensus criteria. Randomization resulted in 19 patients in the spleen cell group and 21 in the placebo group. One-yr graft survival was 94 and 100, respectively. Early rejection was more frequent in the spleen cell group (61 vs. 35, p, not significant). The histopathological rejection activity index at 7 d was also higher for the patients in the spleen cell group: 39 of spleen cell treated patients had a score of 4 or higher as opposed to 5 in the placebo group (p < 0.01). The mean score was 2.9 ± 2.8 for the spleen cell group versus 1.3 ± 1.7 for the placebo group (p = 0.034). It is concluded that heat-treated donor spleen cells given within 24 h after liver transplantation were not clinically beneficial and increased the intensity of rejection in 7-d protocol liver biopsies.