BACKGROUND:Anti-interleukin (IL)-2 receptor (IL-2R) antibodies have been used as rejection prophylaxis after organ transplantation. Despite this induction treatment, acute rejections may occur. We wondered whether these rejections developed via the IL-2/IL-2R pathway. METHODS: In a prospective trial using BT563, a murine IgG1 anti-IL-2R antibody, for rejection prophylaxis after heart transplantation, 20 patients were treated in combination with cyclosporine from the day of transplantation (group A). As a control group, 31 patients were also treated with BT563, but in these patients, cyclosporine treatment was initiated on day 3 (group B). RESULTS: Three patients from group A and two patients from group B died in the first postoperative month (of causes not related to acute rejection) and were left out of the analysis of rejection incidence. Freedom from acute rejection at 1 week after transplantation in group A (14/17; 82%) was lower than in group B (16/29; 55%), although the difference did not reach statistical significance. There was no difference in either the number of acute rejection episodes at 12 weeks or the required rejection treatments between groups A and B. Infectious complications were evenly distributed in both groups. Immunohistochemistry showed that during acute rejection, in the presence of circulating BT563, IL-2R-bearing cells were present in only one of five rejection biopsies (20%), whereas these cells were often present (6/8, or 75%) in rejections occurring in the absence of BT563. The presence of BT563 was associated with a similar difference in the mRNA expression of IL-2 (2/5 vs. 6/8). CONCLUSIONS: Apparently, despite adequate blockade of the IL-2/IL-2R pathway, patients may develop acute rejection, reflecting the redundancy of the cytokine network. The ever-present IL-15 may well be a candidate for overtaking the role of IL-2.
RCT Entities:
BACKGROUND: Anti-interleukin (IL)-2 receptor (IL-2R) antibodies have been used as rejection prophylaxis after organ transplantation. Despite this induction treatment, acute rejections may occur. We wondered whether these rejections developed via the IL-2/IL-2R pathway. METHODS: In a prospective trial using BT563, a murine IgG1 anti-IL-2R antibody, for rejection prophylaxis after heart transplantation, 20 patients were treated in combination with cyclosporine from the day of transplantation (group A). As a control group, 31 patients were also treated with BT563, but in these patients, cyclosporine treatment was initiated on day 3 (group B). RESULTS: Three patients from group A and two patients from group B died in the first postoperative month (of causes not related to acute rejection) and were left out of the analysis of rejection incidence. Freedom from acute rejection at 1 week after transplantation in group A (14/17; 82%) was lower than in group B (16/29; 55%), although the difference did not reach statistical significance. There was no difference in either the number of acute rejection episodes at 12 weeks or the required rejection treatments between groups A and B. Infectious complications were evenly distributed in both groups. Immunohistochemistry showed that during acute rejection, in the presence of circulating BT563, IL-2R-bearing cells were present in only one of five rejection biopsies (20%), whereas these cells were often present (6/8, or 75%) in rejections occurring in the absence of BT563. The presence of BT563 was associated with a similar difference in the mRNA expression of IL-2 (2/5 vs. 6/8). CONCLUSIONS: Apparently, despite adequate blockade of the IL-2/IL-2R pathway, patients may develop acute rejection, reflecting the redundancy of the cytokine network. The ever-present IL-15 may well be a candidate for overtaking the role of IL-2.
Authors: Takeshi Nakajima; Vyachesav Palchevsky; David L Perkins; John A Belperio; Patricia W Finn Journal: Semin Immunopathol Date: 2011-01-27 Impact factor: 9.623