[Effect of Graft Composition on Viral Infection and Survival after Allogeneic Hematopoietic Stem Cell...

To investigate the effect of infusing different doses of graft cells on viral infections and survival after allogeneic hematopoietic stem cell transplantation (allo-HSCT).

Clinical data of 99 patients with hematological diseases who underwent allo-HSCT in Shanxi Bethune Hospital were retrospectively analysed. The proportion of mononuclear cells (MNC) was counted microscopically, the proportions and absolute counts of CD34⁺ cells and lymphocyte subsets (including CD3⁺T, CD4⁺T, CD8⁺T, CD4⁺CD8⁺T, B, and NK cells) were detected by flow cytometry, and the infusion dose of each cell types was calculated. The patients were divided into high-dose group and low-dose group based on the median value of the infused cell dose. The effects of different doses of various graft cells on post-transplant viral infections (CMV, EBV, BKV) and survival were analyzed.

The low-dose MNC (< 7.97×10⁸/kg) and high-dose CD4⁺CD8⁺T cell (≥3.02×10⁶/kg) groups had a higher Epstein-Barr virus (EBV) infection rate (P =0.031; P =0.020). The high-dose CD34⁺ cell group and low-dose CD3⁺ T, CD8⁺ T and natural killer (NK) cell groups showed a trend toward higher EBV infection rates, but the differences were not statitsically significant (P >0.05). There was no significant difference in the rates of EBV infection between the high-dose and low-dose groups of CD4⁺T and B cells (P >0.05). Multivariate analysis revealed that the doses of MNC and CD4⁺CD8⁺ T cells in the graft were independent factors influencing EBV infection (P =0.023; P =0.016). The doses of cells in the graft showed no significant impact on CMV and BKV infection, or patient survival (P >0.05).

Infusing a lower dose of MNC and a higher dose of CD4⁺CD8⁺T cells increases the risk of EBV infection, but does not affect the survival outcome.