Mesenchymal Stromal Cells as Prophylaxis for Graft-versus-host Disease in Haplo-identical Hematopoietic Stem Cell Transplantation Recipients With Severe Aplastic Anemia? - A Systematic Review and Meta-analysis

Abstract

Background: Mesenchymal stromal cells (MSCs) are an emerging prophylaxis option for graft-versus-host disease (GVHD) in haplo-identical hematopoietic stem cell transplantation (haplo-HSCT) recipients with severe aplastic anemia (SAA), but studies have reported inconsistent results. This systematic review and meta-analysis evaluates the efficacy of MSCs as prophylaxis for GVHD in SAA patients with haplo-HSCT. Methods: Studies were retrieved from PubMed, EMBASE, Cochrane, Web of Science and http://clinicaltrials.gov from establishment to February 2020. Twenty-nine single-arm studies (n = 1456) were included, eight (n = 241) studies combined with MSCs and eleven (n = 1215) reports without MSCs in haplo-HSCT for SAA patients. The primary outcomes were the incidences of GVHD. Other outcomes included 2-year overall survival (OS) and the prevalence of cytomegalovirus viremia (CMV). Odds ratios (ORs) were calculated to compare the results pooled through random or fixed effects models. Results: Between MSCs and no MSCs groups, no significant differences were found in the pooled incidences of acute GVHD (56.0%, 95%CI: 48.6%-63.5% vs. 47.2%, 95%CI: 29.0%-65.4%; OR 1.43, 95%CI: 0.91-2.25; p = 0.123), grade II-IV acute GVHD (29.8%, 95%CI: 24.1%-35.5% vs. 30.6%, 95%CI: 26.6%-34.6%; OR 0.97, 95%CI: 0.70-1.32; p = 0.889), chronic GVHD (25.4%, 95%CI: 19.8%-31.0% vs. 30.0%, 95%CI, 23.3%-36.6%; OR 0.79, 95%CI 0.56-1.11; p = 0.187). Furtherly, there was no obvious differences in 2-year OS (OR 0.98, 95%CI 0.60-1.61; p = 1.000) and prevalence of CMV (OR 0.61, 95%CI 0.40-1.92; p = 0.018).Conclusions: Our meta-analysis indicates that the prophylactic use of MSCs co-transplantation is not an effective option for SAA patients undergoing haplo-HSCT. Hence, the general co-transplantation of MSCs for SAA haplo-HSCT recipients may lack of evidence-based practice.