Disturbance in the Reconstitution of Distinct T-Cell Subsets and the Incidence of Gvhd Following Allo-Hsct in Pediatric Patients With Non-Malignant Hematological Disorders Publisher Pubmed



Bayegi SN^{1, 2} ; Hamidieh AA² ; Behfar M² ; Bozorgmehr M³ ; Saghazadeh A^{4, 5} ; Tajik N^{1, 6} ; Delbandi AA^{1, 6} ; Zavareh FT^{4, 7} ; Delavari S^{4, 9} ; Shekarabi M⁶ ; Rezaei N^{4, 8, 10}
Source: Immunology Letters Published:2023

Abstract

Background: The reconstitution of different T-cell subsets following allogeneic hematopoietic stem cell transplantation (allo-HSCT) is critical for efficient pathogen protection and the prevention of graft-versus-host disease (GvHD). In particular, studies have highlighted the importance of balanced ratios of regulatory T-cells (Tregs) and distinct functionally T-cells in preventing acute and chronic GvHD. Methods: We evaluated the regeneration of CD4 and CD8 T-cell subpopulations in nine pediatric patients with non-malignant disorders following allo-HSCT from a fully HLA-identical donor. Results: CD4 and CD8 T-cells were higher 12 months after the transplant but still lower than in healthy controls and pre-transplant. However, we found after allo-HSCT, central memory and effector memory cell subsets were the predominant phenotypes in the CD4 and CD8 T-cell populations, respectively. In patients who had developed acute GvHD, there was an increase in the frequency of TEMRA (effector memory T cells that re-express CD45RA) cells within the CD4 T-cell population. Meanwhile, in patients with chronic GvHD, we observed a decrease in Th1 cells in CD4 T-cells and effector memory cells within the CD8 T-cell population. In addition, we found decreased TEMRA cell subsets in CD4 and CD8 T-cell populations in chronic GvHD. Conclusion: Our findings suggest a possible relationship between the influence of acute GvHD and its prevention on delayed CD4 T-cell reconstitution and, reciprocally, unbalanced regeneration of CD4 and CD8 T-cell subsets in the development of chronic GvHD. © 2023