'Rejection or infection' predictive value of T-cell subject ratio, before and after heart transplantation.

Peripheral T-cell subsets were monitored in ten heart and two heart-lung recipients pre- and up to one year post-operatively. Prior to transplantation four patients had T-helper/T-cytotoxic suppressor ratios (TH/TS-C) above the range for normal healthy controls and all required treatment for rejection episodes, as compared with three of eight patients whose pre-transplantation ratios were within the normal range. No patient with high TH/TS-C ratios developed cytomegalovirus infection as compared with all of the eight patients with normal ratios. Post-transplantation cytomegalovirus infection was the major cause of alterations in TH/TS-C ratios. T-cell subset inversion always preceded the diagnostic rise in cytomegalovirus antibody titre in both primary and secondary cytomegalovirus infections. Inversion was also noted with Pneumocystis carinii infection. Reversal of the TH/TS-C ratio was due to a major increase in the absolute numbers of TS-C cells and was usually followed by a rise in the number of cells expressing a natural killer cell phenotypic marker (Leu-7). All patients with primary cytomegalovirus and two of four cases with secondary cytomegalovirus retained inversion throughout follow-up and showed significantly increased numbers of TS-C and Leu-7 bearing cells. However, the absolute numbers of TH fell by 200 days after transplantation in all patients irrespective of their TH/TS-C ratio. Although TH/TS-C ratio inversion was a predictor of cytomegalovirus infection, no association was found between changes in T-cell subsets after transplantation and rejection episodes.