Peritoneal and Peripheral B‐1‐Cell Populations in Patients with Endometriosis

Abstract

Abstract Objective: The purpose of this study was to investigate the frequency of B‐1 cells in the peritoneal cavity and peripheral blood of patients with endometriosis. Materials and Methods: We examined 31 patients with endometriosis and 14 normal nonpregnant women. Peripheral blood cells and peritoneal exudate cells (PECs) were stained with FITC or PE‐labeled anti‐CD5/CD19 monoclonal antibodies. Immunofluorescence analysis was performed using a flow cytometer. The significance of differences between the patient and control groups was determined by the non‐parametric Mann‐Whitney test. Results: There was no significant difference in the percentages of B‐1 cells in the peripheral blood of women with and without endometriosis (median, 22.7%; range, 4.7–92.3% vs median, 20.05%; range, 11.1–12.6%, respectively). Endometriosis patients with antinuclear antibodies (ANAs) demonstrated significantly elevated B‐1 cells compared to both endometriosis patients without ANAs and normal controls (p < 0.005 and p < 0.05, respectively). Endometriosis patients demonstrated significantly higher B‐1 cell populations (B‐1 cells/total B‐cell ratio) in PECs than did non‐endometriosis patients (p < 0.05). Conclusions: The peripheral B‐1‐cell population in patients with endometriosis is related to ANA production. B‐1 cells might play important roles in the development of endometriosis through autoantibody production.