E-rosette forming cell numbers in the blood of human renal allograft recipients.

The incidence of circulating T lymphocytes (ET-RFC) and a sub-population of T lymphocytes (EE-RFC) were monitored in the blood of seventy-one cadaver renal allograft recipients for the first 2 months after transplantation. In patients with uneventful post-operative courses, the incidence of both ET-RFC and EE-RFC fell promptly upon initiation of immunosuppression returning approximately to pre-operative levels 3-5 weeks after operation; the fall in cell numbers was greatest in those patients receiving adjunct ALG therapy. With the onset of an acute rejection episode, the EE-RFC level rose quickly eventually exceeding the pre-operative level; in 88% (thirty episodes) of cases this rise occurred 1-6 days before clinical diagnosis of rejection and in 12% of cases on the same day as clinical diagnosis. The incidence of ET-RFC rose in conjunction with some cases of acute rejection but remained unchanged in other cases. It is suggested that measurement of the incidence of EE-RFC in blood is valuable in predicting the onset of acute rejection and for the differential diagnosis of acute rejection and ischaemic renal damage.