[Changes in the lymphocyte subpopulations in a patient with orthotopic transplant of the liver].

Earlier experimental studies have shown that the cyclosporin immunosuppressive effect (CsA) can be modulated by drug timing as well as dose. More specifically treatment during the night was constantly associated with a statistically significant improvement in the prevention or delay of allograft rejection. The present study reports on the circadian variations in T-lymphocyte subpopulations in the peripheral blood of a patient given an orthotopic liver allograft and treated with CsA and steroids. In particular, a statistically significant circadian rhythm (p = 0.012) was observed for the T-helper (OKT4) subset with a peak time (acrophase) occurring during the night at 4:27 A.M. In this patient, CsA treatment was, therefore, adapted to the T-helper cycle with the aim of marching CsA blood level variations to that curve. The results suggest that CsA timing can provide a tool for daily dose reduction and then improve the success rate of drug treatment.