INTEREST IN AND LIMITATIONS OF MONOCLONAL ANTI-T-CELL ANTIBODIES FOR THE FOLLOW-UP OF RENAL TRANSPLANT PATIENTS

Abstract

The OKT series of anti-T cell monoclonals was used on 442 occasions in 41 renal allograft recipients in a 6-12 mo. follow-up study. Standard immunosuppressive therapy (including antithymocyte globulin in 26 patients) tended to decrease the helper-inducer/suppressor-cytotoxic cell ratio (OKT4/OKT8). Of 35 renal failure episodes, 71% were associated with increased OKT4/OKT8 ratios. Of the renal failure episodes, 23% were associated with dramatically decreased OKT4/OKT8 ratios. At least half of these cases could be explained by a cytomegalovirus infection. Similar infections were found in 6 of 17 patients with low OKT4/OKT8 values in the absence of renal failure. The use of anti-T cell monoclonals for the diagnosis of rejection was suggested because only 9 episodes of transient increase in the OKT4/OKT8 ratio were observed in the absence of rejection. The interest of this new method for the immunological follow-up of transplanted patients is limited by the difficulty in interpreting a significant percentage of tests because of the presence of doubly labeled cells (OKT4+OKT8+) or the significant discrepancy between the number of OKT3+ cells and total cells labeled with OKT4 and/or OKT8 antibodies; gross lymphocytopenia, most often observed in patients receiving antithymocyte globulins plus steroids; and the clinically unexplained shifts in the T cell subset ratios mentioned above.