Plasma nitric oxide is associated with the occurrence of moderate to severe acute graft-versus-host disease in hemopoietic stem cell transplant recipients

Abstract

Background and Objectives. Nitric oxide (NO) has been implicated as one of the mediators of acute graft-versus-host disease (GVHD) but reports on its measurement during hemopoietic stem cell transplantation (HSCT) in humans are scarce. The present study was conducted to measure the plasma NO in HSCT recipients in order to delineate its relationships with acute GVHD. Design and Methods. Thirty-nine randomly selected patients undergoing HSCT were recruited. Thirty-one patients received an allogeneic transplant (ALLO) from HLA-identical siblings (n=20), a haploidentical parent (n=1) or matched unrelated donors (n=10). Eight patients received an autologous (AUTO) HSCT. Plasma levels of nitrite/nitrate (NO2-/NO3-), the end-product of NO, were measured by chemiluminescence and the results were correlated with the occurrence and severity of acute GVHD. Results. Baseline NO2-/NO3- levels before HSCT were similar in the ALLO and AUTO patients (17.4 vs 21.1 μmol/L, p>0.05). Significant increases in plasma NO2-/NO3- (> 2 times the baseline level) were found in all 13 patients with acute GVHD ≥ grade 2, in 15 out of 18 patients with acute GVHD grade ≤ 1 and 3 out of 8 patients receiving autologous HSCT. The increase in NO2-/NO3- among the three groups of patients was significantly different (135.5 vs 56.3 vs 36.6 μmol/L, p < 0.001). The average NO production, calculated as the area under the curve, was also significantly differently among the three groups of patients (44.5 vs 30.0 vs 23.8 μmol/L, p < 0.001). Interpretation and Conclusions. Plasma NO in HSCT recipients is quantitatively associated with the occurrence of acute GVHD; its role remains to be determined. ©2001, Ferrata Storti Foundation.