RESUMO
AbstractObjective: To investigate the role and mechanism of circulating follicular helper T cells (cTfh), extrafollicular helper T cells, B cells and their subsets in chronic graft-versus-host disease (cGVHD) after transplantation. METHODS: Peripheral blood of cGVHD 64 patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the First Affiliated Hospital of Soochow University from 2016 to 2019 were collected. The percentage of cTfh cells, extrafollicular helper T cells, B cells and subsets were detected by flow cytometry. The healthy donors were detected as control. Percentage of each cell subpopulation between the two groups were compared by the two-tailed Students' T test. RESULTS: The percentage of circulating follicular helper T cells (cTfh, CD4+CXCR5+) was markedly decreased in patients with cGVHD as compared with that in the healthy donors (0.53%±0.10% vs 3.91%±0.60%, P<0.001). The percentage of extrafollicular helper T cells (CD44hiCD62LloPSGL-1loCD4+T) of the patients in cGVHD and the healthy donors were 8.86%±0.45% and 5.38%±0.79% (P=0.003). A significant change in B cell subsets was found in the patients with cGVHD. The two types of antigen-stimulate CD27+ B cell: the percentages of pre-GC B cells (CD19+IgD+CD38hiCD27+) and plasmablast/plasma cells (PB/PC, CD19+IgD-CD38hiCD27+) of patients with cGVHD were 20.91%±2.70% and 41.05%±5.00%, respectively, which were significantly higher than those in healthy donors (P=0.005, P=0.014). Meanwhile, the percentage of unstimulated CD27- B cells in patients with cGVHD was significantly reduced, especially the naive B cells (CD19+IgD+CD38loCD27-, 12.59%±2.63%, P=0.025). There was a positive correlation between the percentage of extrafollicular helper T cells and plasmablast/ plasma cells (PB/PC) in cGVHD patients (r=0.43). CONCLUSION: Compared with healthy donor, cTfh cells, extrafollicular helper T cells and B cell subsets in the peripheral blood of patients with cGVHD after transplantation changed in varying degress.
