RAISED LEVELS OF TUMOR-NECROSIS-FACTOR-ALPHA (TNF-ALPHA) IN CARDIAC TRANSPLANT PATIENTS

Enzyme immunoassay is used to probe serum and plasma levels of tumor-necrosis factor-alpha (TNFalpha) in human heart transplant patients during the first few months post-transplantation. Detectability of TNFalpha was increased by heat-pretreatment of serum (56-degrees-C for 30 minutes), in order to inactivate inhibitors of the immunoassay present in the sera. In EDTA-treated plasma samples such treatment was not necessary, thus suggesting the possible involvement of complement in such inhibition. Compared with samples from control (healthy) volunteers, transplant patients frequently displayed elevated levels of TNFalpha, especially in the first few weeks post-transplantation. However, increased cytokine levels did not correlate with histologically (biopsy)-determined rejection episodes. We were unable to detect interleukin-6 (IL-6) in plasma samples of heart transplant patients.