Association between CD34+ and CD3+ T-cells in allogeneic grafts and acute graft-versus-host disease in children undergoing allogeneic hematopoietic stem cell transplantation: A single-center study

Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). We examined the association between the composition of the cell subsets present in allogeneic grafts (allografts) and the occurrence and severity of aGVHD in pediatric patients.We retrospectively analyzed 80 consecutive pediatric patients undergoing allo-HSCT at our center.Both univariate and multivariate analyses showed that the number of CD34+ and CD3+ T-cells in allografts were the two highest risk factors associated with II-IV aGVHD. Using receiver operating characteristic analysis, the cutoff levels of the allo-HSCT cell doses were used to divide the recipients into low-dose and high-dose groups. The 100-day cumulative incidence of II-IV aGVHD in the high-dose CD34+ and CD3+ T-cells group was significantly higher than that of the low-dose group (CD34+: 57% vs. 29%, p = 0.009; CD3+: 63% vs. 18%, p < 0.001). No other clinical factors or cell subsets correlated with aGVHD incidence.Our analysis indicates that the CD34+ and CD3+ T-cell numbers in the allografts could be the risk factors for the development of severe aGVHD (level II-IV). Further studies should aim to optimize the critical number of CD34+ and CD3+ T-cells to reduce the risk of severe aGVHD occurrence in pediatric patients.