Relationships between tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and hematopoietic activity in healthy adults

To investigate the relationship between hematopoiesis and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), we measured soluble TRAIL concentrations, reticulocytes, hemograms, and anthropometric variables in 156 healthy subjects. Serum TRAIL concentrations were analyzed by an enzyme immunoassay. Serum ferritin, thyroid hormone, total cholesterol, creatinine, and blood glucose levels were determined. There were no significant differences in blood cell counts and biochemical parameters between the subjects with TRAIL less than 63.5 pg/ml and TRAIL at least 63.5 pg/ml, nor between those with TRAIL at most 47.5 pg/ml (20th percentile) and TRAIL >= 80.9 pg/ml (80th percentile). However, hemoglobin, mean corpuscular hemoglobin (MCH), and MCH concentration (MCHC) averaged 15.6 +/- 0.8 g/dl, 31.9 +/- 1.1 pg, and 34.5 +/- 0.9 g/dl in the subjects with TRAIL at most 47.5 pg/ml, which were significantly above the values in those with TRAIL at least 80.9 pg/ml (14.7 +/- 0.9 g/dl, 30.4 +/- 1.3 pg, and 33.2 +/- 1.2 g/dl, P < 0.05, respectively). Serum TRAIL levels were significantly higher in the subjects with decreased MCH than in those with elevated MCH. Soluble TRAIL concentrations were significantly correlated with hemoglobin (r=-0.25, P < 0.05), MCH (r=-0.32, P < 0.05), and MCHC (r=-0.29, P < 0.05), but not correlated with leukocyte differentials and platelet counts. In conclusion, soluble TRAIL does not seem to influence leukocyte and platelet production but has an important relationship to erythropoiesis in healthy adults.