T lymphocyte subsets and NK cell cytotoxicity in chronic hemodialysis patients. The effect of recombinant human erythropoietin (rHu-EPO) treatment.

We investigated subpopulations of T lymphocytes, NK cell number and cytotoxic activity in 14 chronic uremic patients on regular hemodialysis treatment. We observed a significantly decreased absolute lymphocyte number and percentage of CD3 cells. Relative numbers of CD16 cells were significantly elevated, but NK cell cytotoxic activity was within a normal range. Nine patients with chronic renal anemia on maintenance hemodialysis were enrolled in rHu-EPO treatment trial. The treatment was continued till the hematocrit level reached 30%. Each of the patients had corrected anemia and well-being. After 12 weeks of the treatment we observed in these patients decreases in CD3, CD4, CD8 and CD16 cell numbers and elevation of CD4/CD8 ratio. Cytotoxic activity of NK cells did not change significantly. Presented results indicate that chronic hemodialysis patients have significantly diminished lymphocyte number. rHu EPO treatment affects the T lymphocyte subsets inducing a deep decrease of CD8 and CD16 cell percentage leading to normalisation of the CD4/CD8 ratio.