Work

4: Influence of HLA Disparity and Graft Lymphocytes on Allogeneic Engraftment and Survival after Umbilical Cord Blood Transplant in Adults

Year: 2007

Type: article

Abstract: Graft nucleated cell and CD34+ hematopoietic progenitor cell dose are predictors of allogeneic engraftment and survival in umbilical cord blood (UCB) recipients. In this single institution prospective phase II trial, flow cytometric analyses of CD34+ progenitor and lymphocyte populations in unmodified single unit HLA-disparate UCB grafts infused into 31 consecutive adults (median age 41 years, range 20-64) receiving myeloablative conditioning were compared with clinical outcomes. Median infused UCB graft nucleated cells and CD34+ dose was 2.2 × 107/kg and 1.2 × 105/kg respectively. Day to absolute neutrophil count > 500/L with full donor chimerism averaged 27 days (range 12-41). Univariate analyses demonstrated that UCB graft infused cell doses of CD34+ (p=0.015), CD3+ (p=0.024) and CD34+HLADR+CD38+ progenitors (p=0.043) correlated with neutrophil engraftment. High-resolution matching for HLA-Class II (DRB1) resulted in improved event-free survival (EFS) (p=0.02) and decreased risk for acute graft versus host disease (GVHD) (p=0.004). Early mortality (prior to post-transplant day +28) occurred in three patients, while twenty-six patients achieved myeloid engraftment. These results suggest that UCB graft matching at DRB1 is an important risk factor for acute GVHD and survival, while higher UCB graft cell doses of CD34+, committed CD34+ progenitors and CD3+ T-cells favorably influence UCB allogeneic engraftment.

Source: Transplantation and Cellular Therapy

DOI: 10.1016/j.bbmt.2007.08.012