HNK-1+ (Leu-7) and other lymphocyte subsets in long-term survivors with renal allotransplants.

At 5 or more years after renal transplantation, 42 patients were studied for their lymphocyte subsets to Leu-1, Leu-2, Leu-3, and Leu-7. It was found that, in this group of patients who ranged from 25 to 60 years of age, there was a significant decrease in the number of T helper cells and a decrease in the absolute level of T lymphocytes, with no significant change in the number of T suppressor cells. On a relative basis, the helper/suppressor ratio was decreased in patients when compared with normal persons. This was due to an increase in the relative numbers of suppressor cells. It was demonstrated that the Leu-7+ subset, which marks the NK population, was significantly elevated, in relative proportion, in peripheral blood when compared with controls. This was not seen on an absolute basis. The age-dependence of the relative numbers of Leu-7+ cells was seen in the normal control population and in the transplant cohort. There was no significant correlation between lymphocyte subset measurements and delayed-type hypersensitivity skin tests in the transplant population. A finding of interest is that 6 of the patients who had been treated for malignant disease during their posttransplant course had significantly higher numbers of Leu-7+ cells on a relative basis. In 5 of these patients, for whom data was available on absolute numbers, there was also a highly significant difference in the absolute numbers of Leu-7+ cells in these treated and surviving allograft recipients. It is speculated that this finding may suggest that an increase in Leu-7+ cells marks posttransplant patients who have a successful outcome following the treatment of malignancy, for which they are at increased risk.