Correlation of Professional Antigen‐Presenting Tbet+CD11c+ B Cells With Bone Destruction in Untreated Rheumatoid Arthritis.

Autor: McGrath, Sarah, Grimstad, Kristoffer, Thorarinsdottir, Katrin, Forslind, Kristina, Glinatsi, Daniel, Leu Agelii, Monica, Aranburu, Alaitz, Sundell, Timothy, Jonsson, Charlotte A., Camponeschi, Alessandro, Hultgård Ekwall, Anna‐Karin, Tilevik, Andreas, Gjertsson, Inger, Mårtensson, Inga‐Lill
Předmět:
Zdroj: Arthritis & Rheumatology; Aug2024, Vol. 76 Issue 8, p1263-1277, 15p
Abstrakt: Objective: Subsets of CD21−/low memory B cells (MBCs), including double‐negative (DN, CD27−IgD−) and Tbet+CD11c+ cells, are expanded in chronic inflammatory diseases. In rheumatoid arthritis (RA), CD21−/low MBCs correlate with joint destruction. However, whether this is due to the Tbet+CD11c+ subset, its function and pathogenic contribution to RA are unknown. This study aims to investigate the association between CD21−/lowTbet+CD11c+ MBCs and joint destruction as well as other clinical parameters and to elucidate their functional properties in patients with untreated RA (uRA). Methods: Clinical observations were combined with flow cytometry (n = 36) and single‐cell RNA sequencing (scRNA‐seq) and V(D)J sequencing (n = 4) of peripheral blood (PB) MBCs from patients with uRA. The transcriptome of circulating Tbet+CD11c+ MBCs was compared with scRNA‐seq data of synovial B cells. In vitro coculture of Tbet+CD11c+ B cells with T cells was used to assess costimulatory capacity. Results: CD21−/lowTbet+CD11c+ MBCs in PB correlated with bone destruction but no other clinical parameters analyzed. The Tbet+CD11c+ MBCs have undergone clonal expansion and express somatically mutated V genes. Gene expression analysis of these cells identified a unique signature of more than 150 up‐regulated genes associated with antigen presentation functions, including B cell receptor activation and clathrin‐mediated antigen internalization; regulation of actin filaments, endosomes, and lysosomes; antigen processing, loading, presentation, and costimulation; a transcriptome mirrored in their synovial tissue counterparts. In vitro, Tbet+CD11c+ B cells induced retinoic acid receptor–related orphan nuclear receptor γT expression in CD4+ T cells, thereby polarizing to Th17 cells, a T cell subset critical for osteoclastogenesis and associated with bone destruction. Conclusion: This study suggests that Tbet+CD11c+ MBCs contribute to the pathogenesis of RA by promoting bone destruction through antigen presentation, T cell activation, and Th17 polarization. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index