THE VALUE OF EXTRACORPOREAL PHOTOCHEMOTHERAPY IN RENAL TRANSPLANT REJECTION INHIBITION

Abstract

The aim of the study was to determine the value of extracorporeal photochemotherapy (EPCT) in the induction of tissue tolerance in renal transplantation. EPCT was applied to 24 renal transplant recipients in early postoperative period, the control group consisted of paired transplant recipients. In the group using EPCT over a three-year period of observation no clinical or histological signs of rejection were observed. In the control group, histologically confirmed rejection was observed in 4 cases, in 2 cases transplantectomy due to acute rejection. The reducing incidence of infectious complications in the study group compared with the control one (4 and 19 cases, respectively) and decreasing number of hospitalizations on various reasons (8 and 47 cases in the study and control groups, respectively) were also noted. Three-year graft survival was 100% and 83.3% in the study and the control groups, respectively. Using immunological tests in 30 days after transplantation the stable number of cells expressing coactivation molecules (57.7 ± 18.2 and 52.7 ± 23.2%, respectively, p > 0.05) and the density of their co-expression (22.7 ± 6.0 and 19.6 ± 7.0 units, respectively, p > 0.05) were demonstrated, while in the study group, the pronounced and statistically significant reduction both in the amount of cells expressing co-activation receptors (from 57.7 ± 18.2 to 34.5 ± 11.4%, p < 0.05) and in the density of these receptors on naive helper T-lymphocytes (from 22.7 ± 6.0 to 16.8 ± 5.1 units, p < 0.05) was revealed. Thus, it is noted that EPCT provides induction of tolerance to MHC antigens in kidney transplantation due to reducing expression of coactivation molecules which promote the second signaling pathway to T-cell receptor activation.