Infiltration and immunosuppressive function of tumor-associated B cells in gastric cancer patients

Objective To investigate the distribution of B cells in both tumor and non-tumor tissues of gastric cancer patients, analyze their phenotypic characteristics and explore the impact on T cell proliferation. Methods Immunohistochemical staining was utilized to detect the expression of B cell surface marker CD19 in tumor and non-tumor tissues from 33 gastric cancer patients. The expression levels of chemokine receptors and immunoglobulin molecules on B cells in both tumor and non-tumor tissues were measured using flow cytometry. Chemotaxis experiments were conducted to examine the role of the CXCL12-CXCR4 axis in B cell chemotaxis. B cells isolated and purified from both tissue types were co-cultured with autologous peripheral T cells to assess their effect on T cell proliferation. Results There were significantly more B cells infiltrated in tumor tissues than those infitrated in the non-tumor tissues of gastric cancer patients (P