RESUMO

OBJECTIVE: Chronic graft-versus-host disease (cGVHD) is a significant complication following allogenic hematopoietic stem cell transplantation, often necessitating therapeutic interventions such as rituximab (RTX) and cyclosporin A (CsA). This study aims to elucidate the mechanisms by which RTX and CsA jointly address B-cell dysregulation in cGVHD, providing a theoretical foundation and scientific rationale for the treatment and prognostic evaluation of this condition. METHODS: A total of 30 cGVHD mouse models were established by subjecting recipient mice to total body irradiation followed by injection of a mixed suspension of bone marrow cells and splenocytes from donor mice. From Day 2 to Day 29 post-model establishment, the mice received subcutaneous administration of RTX and CsA. Throughout the study, body weight, clinical cGVHD scores, and survival rates were monitored. Blood samples were collected via the orbital venous plexus. Serum levels of B-cell activating factor (BAFF) and pro-inflammatory factors were measured using enzyme-linked immunosorbent assay (ELISA), and the ratio of regulatory B cells (Bregs) in the blood sample was assessed via flow cytometry. RESULTS: Mice with cGVHD exhibited a 14.5% decrease in body weight, elevated clinical scores, and more severe symptoms compared to the control group. Notably, all mice in both the cGVHD and control groups survived until the conclusion of the study. Induction of cGVHD resulted in B-cell dysregulation, evidenced by elevated serum BAFF levels and a decreased proportion of Bregs. However, treatment with RTX combined with CsA ameliorated B-cell dysregulation and significantly reduced serum levels of pro-inflammatory factors in cGVHD mice, with decreases of 39.78% in TNF-α and 37.89% in IL-6. CONCLUSION: The combination of RTX and CsA effectively mitigates B-cell dysregulation in cGVHD, thereby reducing the severity and progression of the disease.