The efficacy and immunological differences of anti-t lymphocyte globulin and anti-thymocyte globulin in allogeneic hematopoietic stem cell transplantation

Abstract Objective To analyze the efficacy and immunological differences of anti-T-lymphocyte globulin ( ATLG ) and anti-thymocyte globulin ( ATG ) in allogeneic hematopoietic stem cell transplantation. Methods We retrospectively reviewed the patients who underwent allogeneic hematopoietic stem cell transplantation in the First Affiliated Hospital of Zhengzhou University between August 2023 and December 2024 . According to the use of ATLG or ATG before transplantation to prevent graft-versus-host disease, they were divided into the ATLG group (n=44) and the ATG group (n=136). We analyzed the incidence of GVHD, Epstein–Barr virus (EBV) and cytomegalovirus (CMV) infections, recurrence rates, and non-relapse mortality (NRM) in the two groups. The peripheral blood counts and lymphocyte subset data were collected at 1 month, 2 months and 3 months post-hematopoietic stem cell reinfusion to assess the immunological differences. Results There was no significant differences between groups in the incidence of II-IV aGVHD, III-IV aGVHD, cGVHD ,CMV-related infection, recurrence rate, or NRM. In the ATG group, 21 patients (15.44 % ) developed EBV-associated infection, which was significantly higher than that in the ATLG group ( P = 0.005 ). At 1 month, 2 months and 3 months post-transplant, absolute counts of peripheral lymphocytes, monocytes, eosinophils, and basophils showed no significant differences between groups. The lymphocyte subset analysis revealed that the CD19 + B cell count in the ATLG group was significantly higher than those in the ATG group at 2 months ( Median = 66.09, P = 0.020 ) and 3 months ( Median = 70.68, P = 0.014 ) post-transplant. No significant differences were observed in CD4 + T cells, CD8 + T cells, NK cells or NKT cells between the groups. Conclusion Compared with the ATG group, ATLG was associated with a lower incidence of EBV-associated infection and a faster CD19 + B cells recovery, suggesting better humoral immune reconstruction. The rates of GVHD , relapse and NRM were comparable between the two groups.