Correlations between pretransplantation patient-antidonor cytokine responses and aGVHD. Cytokine profiles from pre-BMT GVH direction PBMC MLRs. MLRs were performed using whole PBMCs from donors reacting against irradiated whole PBMCs taken from the corresponding patient before transplantation. Supernatants were frozen on day 7 of the MLR for later assessment of the cytokines IL-5, IL-10, IL-13, IFN-γ, and TNF-α. All cytokines were measured by ELISA. Also shown are the calculated CTLp frequencies and grade of GVHD as assessed routinely during the BM transplant matching and during posttransplantation care at Hammer-smith Hospital. Units shown are pg/mL for cytokine levels and estimated CTLp frequencies as 1/(1000×n); 1000 indicates an extremely low estimated frequency of one per million.