Fine-needle aspiration cytology in the prediction and diagnosis of acute rejection episodes in man.

The rate of spontaneous proliferative activity of blood leucocytes, the presence of donor-directed cytotoxic cells in the circulation of transplant recipients and the fine-needle aspiration cytology of the transplant have been evaluated for the monitoring of acute rejection episodes in 8 recipients of cadaver kidney transplants. We could not find any correlation between the rate of proliferative activity of the appearance of cytotoxic cells in the recipients' circulation on the one hand, and the onset of rejection on the other hand. A detectable blast response, consisting of lymphoblasts and plasmablasts could, however, be seen inside the kidney parenchyma during the early stages of rejection. We propose that the blast response could be used for the monitoring of rejection episodes in kidney transplant recipients.