HGF and graft versus host disease: These discrepancies were generally tolerable at lower biomarker concentrations, for example, below 2,500 pg/mL for HGF, 36,000 pg/mL for elafin, 4,700 pg/mL for ST2 and 1,800 pg/mL forTNFR1 (i.e., concentrations that approximate the clinically important thresholds for GVHD diagnosis).