Impact of very early CD4+/CD8+ T cell counts on the occurrence of acute graft‐versus‐host disease and NK cell counts on outcome after pediatric allogeneic hematopoietic stem cell transplantation

P ¼0.004) first measurable CD4 þ /CD8 þ T cell ratio, compared to patients with no or grade I aGVHD, respectively. At day þ32 after HSCT patients with MUDs and significant aGVHD had higher levels of both CD4 þ and CD8 þ T cell subsets. Low (below median 120/mL) versus highnaturalkiller (NK) cellcountsatday þ32 wereassociated with 3-year event-free survival of 27.4 þ/� 9.0% versus 82.4 þ/� 6.4% (P<0.0001), cumulative transplant-related mortality of 44.7 þ/� 12.2% versus 3.0 þ/� 3.0% (P<0.001) and cumulative relapse incidence of 50.4 þ/� 12.2% versus 15.0 þ/� 6.2% (P ¼0.019), respectively. Conclusions. We conclude that early lymphocyte subset counts following allogeneic HSCT have an association with aGVHD and post transplant outcome. Pediatr Blood Cancer # 2014 Wiley Periodicals, Inc.