Objectives: The purpose of our study was to analyze the
co-transplantation efficacy of umbilical cord mesenchymal stem cells
(UC-MSCs) and peripheral blood stem cells (PBSCs), which is considered
as a novel approach for refractory severe aplastic anemia (RSAA) in
children and adolescents. Methods: Thirty-two children and adolescents
with RSAA were retrospectively reviewed. According to the source of
PBSCs, all patients were divided into two groups (matched sibling donor
group and matched unrelated donor group). Engraftment, graft-versus-host
disease (GVHD) and overall survival (OS) were analyzed. Results: No
adverse events related to UC-MSCs infusion occurred in all patients. The
median time for neutrophil engraftment was 13 (10~23)
days and 15 (11~28) days for platelet. Grade Ⅰ
~ Ⅱ acute GVHD and moderate chronic GVHD were observed
in 21.88% and 12.50% of the cases. No statistically significance was
observed between the MSD and MUD group on engraftment, GVHD and
complications including infection and hemorrhagic cystitis. The median
follow-up time was 38.60 (1.37~140.83) months. To the
date of October 31th 2021, 5 died and 27 (84.38%) survived. The 5-year
OS rate was not statistically significant between the MSD and MUD group
(84.8% ± 10.0% vs 82.4% ± 9.2%, P = 0.674). Conclusions: The
application of UC-MSCs in the treatment of RSAA in PBSC transplantation
is reliable and safe, which can significantly reduce the incidence of
GVHD and severe transplantation-related complications and effectively
improve patients’ life quality. Therefore, the method can be used as an
active treatment option for patients with RSAA.