[Correlation Analysis between Immune Cells in Graft and Early Immune Reconstitution after Allogeneic Hematopoietic Stem Cell Transplantation].

Objective: To investigate the correlation between the types and quantities of immune cells in the graft and early immune reconstitution after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and their influence on clinical prognosis.

Methods: The clinical data of 83 patients with hematological diseases who received allo-HSCT in Shanxi Bethune Hospital from September 2020 to June 2023 were retrospectively analyzed. The number of mononuclear cells (MNC), CD34⁺ cells and lymphocyte subsets (including CD3⁺T, CD3⁺CD4⁺T(Th), CD3⁺CD8⁺T(Ts), NK cells and B cells) infused into the recipients was counted, and the peripheral blood lymphocytes were detected before conditioning and on days 14, 30, 60 and 100 post-HSCT.

Results: Multivariate analysis showed that the number of MNC in the graft affected the recovery of CD4⁺T lymphocytes after HSCT, and the number of CD4⁺T lymphocytes in the graft affected the recovery of NK cells and B cells after HSCT. The patient age, donor sex, stem cell source, degree of HLA matching, use of ATG before HSCT, the occurrence of acute graft-versus-host disease (aGVHD) after HSCT, and viral infection all affect the early cellular immune reconstitution post-HSCT. The number of infused cells had no significant impact on the median engraftment time for neutrophils and platelets after HSCT. Patients with lower numbers of CD3⁺T, CD4⁺T and B cells in the graft were more prone to viral infection after HSCT. However, the cells in the graft had no significant effect on disease recurrence or mortality.

Conclusion: The recovery rate of lymphocyte count after allo-HSCT varies. The numbers of MNC and CD4⁺T cells in the graft may be related to the cellular immune reconstitution after HSCT, while the numbers of CD34⁺,CD3⁺T,CD8⁺T,NK and B cells have no significant effect on the cellular immune reconstruction. The numbers of CD3⁺T,CD4⁺T and B cells in the graft were negatively correlated with viral infection after HSCT, but the cellular components of the graft have no obvious influence on hematopoietic reconstitution, disease recurrence, death, recurrence-free survival(RFS) and overall survival(OS) after HSCT.