Peripheral blood cytotoxic lymphocyte gene transcript levels differ in patients with long-term type 1 diabetes compared to normal controls.

The purpose of this study was to compare mRNA levels of the cytotoxic lymphocyte (CL) gene products: granzyme B (GB), perforin (P), and fas ligand (FasL) in patients with long-term type 1 diabetes and healthy controls. The objective was to utilize this information to follow patients as they undergo islet cell transplantation at our center and to determine if changes in CL gene transcript levels correlate with graft status. We have measured mRNA levels for CL genes in peripheral blood samples from 65 long-term (>5 years) type 1 diabetes patients and 29 healthy controls.

Assessment of cytotoxic lymphocyte gene expression in the peripheral blood of human islet allograft recipients: elevation precedes clinical evidence of rejection.

Studies in nonhuman primates have demonstrated that elevation of the cytotoxic lymphocyte (CL) genes granzyme B, perforin, and Fas ligand in peripheral blood precedes islet allograft rejection. The purpose of this study was to determine whether this approach has utility for prediction of human islet allograft loss. We studied 13 patients who had long-term type 1 diabetes and were treated with steroid-free immunosuppression and given sequential islet cell infusions.