CD180-Associated B-Cell Alterations in Type 1 Diabetes and the In Vitro Effects of Chlorogenic Acid: An Integrated Transcriptomic and Experimental Study

Abstract

Type 1 diabetes mellitus (T1DM) is an autoimmune disease involving progressive loss of pancreatic β-cells. Although B cells have been implicated in T1DM progression, the molecular characteristics associated with disease-related B-cell states remain unclear. Here, we investigated B-cell-associated molecular alterations in T1DM and explored the potential immunomodulatory effects of a natural compound. Public T1DM transcriptomic datasets were analyzed using differential expression analysis, WGCNA, and machine-learning approaches. Single-cell RNA sequencing was used to characterize Cd180 expression across B-cell states. Molecular docking and molecular dynamics simulations were used to explore potential interactions between CD180 and candidate compounds, and an exploratory DARTS assay was performed to assess CGA-associated changes in CD180 proteolytic susceptibility. CD180 expression was examined in pancreatic tissues from vehicle- and MSA-2-treated NOD mice. The effects of chlorogenic acid (CGA) were evaluated in vitro by exposing B cells to CGA during inflammatory stimulation, followed by washing and co-culture with MIN6 cells in CGA-free medium. Integrated transcriptomic analysis identified four T1DM-associated genes (CD180, KCNJ2, STEAP4, and ZXDA), among which CD180 showed the strongest association with B-cell-related immune alterations. Single-cell analysis showed increased Cd180 expression in inflammatory B-cell states together with enrichment of antigen-presentation-related programs. An exploratory DARTS experiment with matched loading-control data suggested altered CD180 proteolytic susceptibility following CGA exposure, although independent reproducibility remains to be established. In vitro, CGA exposure during inflammatory stimulation was associated with reduced CD180 expression in B cells and improved MIN6 cell viability and insulin-secretory responses during subsequent co-culture in CGA-free medium. CD180 is associated with inflammatory B-cell alterations in T1DM and may represent a candidate molecular feature of B-cell dysregulation. CGA treatment was associated with changes in CD180 expression in activated B cells and improved β-cell functional outcomes in vitro. These findings support further investigation of the relationship between CGA and CD180; however, whether the effects of CGA are specifically mediated through CD180 requires further experimental validation.