Lymphocyte-sensitivity to glucocorticoid correlates with the sensitivity to cyclosporin A and tacrolimus in chronic renal failure patients

Abstract

Aims. Association between lymphocyte-sensitivity to immunosuppressants in transplant recipients in vitro and clinical outcomes has been demonstrated. In general, renal transplant recipients are treated with a combination of immunosuppressants such as either glucocorticoid/cyclosporin A (CsA) or glucocorticoid/tacrolimus (FK506) but the pharmacological complementarity of these drugs is still controversial. We examined relationships between the lymphocyte-sensitivities to these immunosuppressants. Methods. We examined lymphocyte-sensitivities to prednisolone (PSL), CsA, and FK506 in vitro, in a total of 190 chronic renal failure (CRF) patients and 140 healthy subjects. The lymphocyte-sensitivity was evaluated from the IC50 value against mitogen-stimulated lymphocyte-blastogenesis in vitro. Results. Statistically significant correlations of the IC50 values in CRF patients between the following pairs of drugs were observed: PSL and CsA (P < 0.0001; n = 129, r = 0.419), PSL and FK506 (P < 0.001; n = 54, r = 0.441), and CsA and FK506 (P < 0.0001; n = 45, r = 0.608). Similar correlations were also observed in lymphocytes from healthy subjects. The population of CRF patients who exhibited high IC50 values (low sensitivities) to PSL and FK506 was significantly larger than that of healthy subjects (P <0.05). Conclusions. Patients who showed low lymphocyte-sensitivity to either of the drugs also may exhibit low sensitivity to the others, and thus they may have a high risk of unsatisfactory outcome under combination therapy after renal transplantation. To overcome this risk, the selection of immunosuppressants is recommended to be restricted according to individual lymphocyte-sensitivities to these drugs in vitro, or alternatively, by addition of other drugs with different mechanisms for immunosuppression.