SOLUBLE TUMOR NECROSIS FACTOR-RECEPTORS ARE NOT A USEFUL MARKER OF ACUTE ALLOGRAFT-REJECTION - A STUDY IN PATIENTS WITH RENAL OR CARDIAC ALLOGRAFTS

In this study, we investigated soluble tumor necrosis factor receptor (sTNF-R) levels in plasma of patients with either a kidney or cardiac allograft when clinical suspicion of acute rejection was raised. In pl asma of patients with acute renal graft rejection, the sTNF-R levels w ere strongly enhanced (20-150 ng/ml) as compared to plasma of patients with stable renal function. Following successful treatment of the rej ection, a gradual decline in sTNF-R levels occurred with improving ren al function, and an inverse correlation between creatinine clearance a nd sTNF-R was found. To determine whether the increase was caused by a n accumulation of constitutively released sTNF-R and lack of clearance by the kidney, or whether the immunological process of the rejection caused the enhancement, we measured sTNF-R in patients suffering from acute cardiac graft rejection but with predominantly stable kidney fun ction. Rejection of a cardiac graft did not lead to a significant enha ncement of sTNF-R levels. However, treatment with ATG or OKT3 did caus e enhanced sTNF-R levels, followed by a decline that reached starting values after 7 days. These results provide evidence that the immune re action that occurs during rejection of a graft does not per se induce discernible changes in sTNF-R levels, whereas that induced by ATG or O KT3 does. Thus, sTNF-R levels are not a reliable marker in transplant recipient monitoring.