Circulating memory B cells and plasmablasts are associated with the levels of serum immunoglobulin in patients with ulcerative colitis

Abstract

Humoural immunity is crucial for the pathogenesis of ulcerative colitis (UC), but the precise perturbation of B cell immunity is poorly understood. This study is aimed at evaluating the numbers of different subsets of circulating memory B cells, plasmablasts, and the levels of serum immunoglobulin in UC patients. Total of 23 patients with active UC and 14 healthy controls (HC) were examined for the numbers of different subsets of circulating memory B cells and plasmablasts before and after treatment with mesalazine for 8–12 weeks by flow cytometry. Disease activity was evaluated by the Mayo clinic score. The levels of serum immunoglobulin, C‐reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were measured in individual subjects. In comparison with that in HC, significantly reduced numbers of IgG+ IgD− CD27+ CD19+ memory B cells, increased numbers of CD20− CD19+ plasmablast subsets, and higher serum IgG levels were detected in UC patients. The concentrations of serum IgG, the numbers of CD138+ CD38+ CD20− CD19+, and IgG+ CD38+ CD20− CD19+ plasmablasts were negatively associated with the numbers of IgG+ IgD− CD27+ CD19+ memory B cells. Furthermore, the values of Mayo clinic score, CRP, or ESR in UC patients were negatively correlated with the numbers of IgG+ IgD− CD27+ CD19+ memory B cells, while positively correlated with the serum IgG levels and the numbers of plasmablast subsets. Following treatment with mesalazine, the numbers of circulating IgG+ IgD− CD27+ CD19+ memory B cells were significantly increased, while the numbers of CD138+ CD38+ CD20− CD19+ and IgG+ CD38+ CD20− CD19+ plasmablasts were reduced in UC patients. These decreased IgG+ IgD− CD27+ CD19+ memory B cells and increased plasmablasts may be involved in the pathogenic process of UC.

The Imbalance of Circulating Follicular Helper T Cells and Follicular Regulatory T Cells Is Associated With Disease Activity in Patients With Ulcerative Colitis

“…B cells secreting autoantibodies against colonic epithelial cells could be isolated from the lesions and peripheral blood of UC patients (7). Circulating CD19 + CD20 − CD38 + CD138 + plasma cells were also significantly elevated in UC patients, and positively correlated with Mayo clinic scores (8). In summary, abnormal immune activation mediated by B cells plays an important role in the pathogenesis and disease activity of UC.…”

“…An abnormal number and function of B cells caused by the interaction between T and B cells are involved in the pathogenesis of UC (4)(5)(6)(7)(8). There are a large number of activated B cells in the lamina propria of UC patients, and a large amount of IgG is expressed in the lesion tissues (6).…”

Aberrant expression of PD-1 on B cells and its association with the clinical parameters of systemic lupus erythematosus

“…Peripheral blood mononuclear cells (PBMCs) were isolated from heparinized whole blood (3 mL) of SLE patients and controls using Ficoll-Hypaque density gradient centrifugation, and stained with FITC-anti-CD3, PE-anti-CD3, APC-anti-CD3, APC-Cy7-anti-CD19, FITC-anti-IgD, APC-anti-CD27, and PE-anti-PD-1 antibodies (all from Biolegend, 9727 Pacific Heights Blvd, San Diego, CA 92121, USA, 1:1000) as appropriate. The cells were acquired in a FACS Verse flow cytometer (BD Bioscience, San Jose, CA 95131, USA) and gated as previously described 29,30 , and analyzed using the Flowjo software (Version X; Tree Star, Ashland, OR, USA). Furthermore, PBMCs isolated from 20 ml fasting blood samples were stained with the anti-CD19 and anti-PD-1 antibodies, and the CD19 + PD-1 + and CD19 + PD-1populations were sorted using FACSAria II (BD Biosciences, 2350 Qume Drive, San Jose, CA 95131, 877.232.8995, USA).…”

Aberrant expression of PD-1 on B cells and their subpopulations in systemic lupus erythematosus and association with clinical parameters

“…Peripheral blood mononuclear cells (PBMCs) were isolated from heparinized whole blood (3 mL) using Ficoll-Hypaque density gradient centrifugation. The gating strategy was based on previous studies 29,30 . Then, FITC-anti-CD3, PE-anti-CD3, APC-anti-CD3, APC-Cy7-anti-CD19, FITC-anti-IgD, APC-anti-CD27, and PE-anti-PD-1 (all from Biolegend, 9727 Pacific Heights Blvd, San Diego, CA 92121, USA, 1:1000) were incubated with the PBMCs.…”