[The effect of rejection crises and immunosuppressive therapy on the lymphocyte subpopulations of patients after kidney transplantation].

The lymphocyte subsets in the peripheral blood were examined 3 times a week in 17 patients receiving a cadaveric renal allograft using 2-color flow cytometry and several combinations of monoclonal antibodies. Patients who experienced a rejection crisis (n = 12) had a significantly higher CD4/CD8-ratio (2.72 +/- 1.26 mean +/- SD) than patients with stable graft function (1.76 +/- 1.33, p less than 0.05). 9/12 patients showed 0-3 days prior to the rejection episode an increase of the CD4/CD8- ratio (greater than or equal to 0.5) and/or a high ratio (greater than or equal to 2.5) with a decrease following antirejection therapy. The activation markers HLA-DR and IL-2 receptor on T cells were increased only during 3/12 rejection episodes. Patients with rejections resistant to prednisone pulse therapy (n = 6) had significantly more lymphocytes/mm3 in the peripheral blood (1111.7 +/- 597.5) than successfully treated patients (n = 6, 336.7 +/- 196.0, p less than 0.02). Antirejection therapy with prednisone pulses and/or antithymocyte globuline resulted in a significant decrease of T lymphocytes (CD3+) with a selective reduction of T helper/inducer cells (CD4+). 6 months after renal transplantation the patients had a higher percentage of suppressor/cytotoxic cells (CD8+) compared to the pretransplant values (26.3 +/- 10.9% vs 17.7 +/- 6.2%, p less than 0.02) and blood donors (16.3 +/- 6.2%, p less than 0.01). Furthermore the percentage of T helper cells (CD4+/CD28-) was significantly higher and the T suppressor-inducer cells (CD4+/CD28+) were significantly lower compared to the controls. Serial flow cytometric determinations of lymphocyte subsets in renal allograft recipients may be helpful in some cases although rejection episodes could not be predicted in the individual patient.