Exploration on the role of regulatory B cell subsets in progression of diabetic retinopathy

KE Diyang; CUI Ling; WANG Hao; DENG Wen; CHEN Lifei; XU Fan; TANG Fen; ZHONG Haibin

doi:10.3969/j.issn.1674-3806.2026.02.12

Abstract：Objective To explore the role and mechanism of regulatory B cells(Bregs)in progression of diabetic retinopathy(DR).Methods Forty male C57/BL6 mice aged 8 weeks were selected and randomly divided into control group and DR group,with 20 mice in each group.The mice in the DR group were intraperitoneally injected with streptozotocin(STZ)at a dose of 30 mg/kg to establish the DR model.The mice in the control group were intraperitoneally injected with the same volume of sodium citrate solution.At the age of 28 weeks,the fundi of the mice were observed by using fundus photography,optical coherence tomography(OCT)and fluorescein fundus angiography(FFA).The spleen and peripheral blood samples of these mice were collected and the levels of Bregs were detected by using flow cytometry.Sixteen patients with DR who were admitted to the People's Hospital of Guangxi Zhuang Autonomous Region from April 2020 to August 2024 were recruited as the case group,among whom 7 patients had proliferative diabetic retinopathy(PDR)and 9 patients had non-proliferative diabetic retinopathy(NPDR),and 12 age-matched healthy individuals undergoing physical examination during the same period were recruited as the healthy control group.The plasma levels of interleukin-10(IL-10),tumor growth factor-β(TGF-β)and programmed death-ligand-1(PD-L1)were detected by using enzyme-linked immunosorbent assay(ELISA),and the correlations between these indicators and the severity of the disease were analyzed.Results Fundus color photography showed that no typical microangiomas or hemorrhagic exudates were observed in the retinas of the mice in both the DR group and the control group.OCT examination revealed the presence of localized hyperreflective foci in front of the optic papilla in the mice of the DR group.The FFA examination results showed that the microcirculation of the retinas in the mice of the DR group was abnormal,specifically manifested as the formation of abnormal arteriovenous anastomoses,which was consistent with the early vascular pathological characteristics of DR lesions.The detection results of flow cytometry showed that the levels of Bregs in the spleen and peripheral blood of the mice in the DR group were significantly lower than those in the control group(P＜0.05).The detection results of ELISA showed that the plasma levels of IL-10,TGF-β,and PD-L1 in the case group were significantly lower than those in the healthy control group(P＜0.05).The levels of plasma IL-10 and PD-L1 in the PDR group were significantly lower than those in the NPDR group(P＜0.05),while there was no statistically significant difference in the plasma TGF-β level between the two groups(P＞0.05).Conclusion Bregs are involved in the occurrence and progression of DR by regulating inflammatory responses.