“…One of the attractive ways to predict the clinical efficacy of immunosuppressive drugs in individual patients is the cellular pharmacodynamics of drugs using PBMCs of patient origin [4][5][6]. It has been reported that the in vitro response of PBMCs to the suppressive effects of immunosuppressive drugs correlate with clinical efficacy in asthma [7], renal transplantation [5,8], minimal change nephrotic syndrome [5,6], psoriasis [4], rheumatoid arthritis [9], and ulcerative colitis [10]. We have also revealed a large individual differences in the PBMC-suppressive effects of glucocorticoids, cyclosporine and tacrolimus between patients, and that patients with PBMCs exhibiting poor response to the drugs in vitro also show low responses to the clinical efficacy of the drugs [4,8,11,12].…”