Manitoba Center of Proteomics and Systems Biology, Departments of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
Department of Immunology, University of Manitoba, Winnipeg, MB, Canada.
Front Immunol. 2022 Jul 28;13:932627. doi: 10.3389/fimmu.2022.932627. eCollection 2022.
Despite immune cell dysregulation being an important event preceding the onset of rheumatoid arthritis (RA), the phenotype of T and B cells in preclinical RA is less understood. The aim of this study was to characterize T and B cell populations in RA patients and their autoantibody (aAb) negative and positive first-degree relatives (FDR).
Cryopreserved peripheral blood mononuclear cells (PBMCs) collected at scheduled visits from aAb-(n=25), and aAb+ FDR (n=10) and RA patients (n=13) were thawed and stained using optimized antibody cocktails as per a specific 13-color T or B cell panel. Immunophenotyping was performed using a Cytoflex LX (Beckman-Coulter) flow cytometer and FlowJo software was used for analyzing the frequency of immune cell populations.
Multicolor flow cytometry experiments identified an increased TIGIT expression in circulating lymphocytes of aAb+ FDR and RA patients, relative to aAb- FDR (P<0.01). These TIGIT T cells exhibited a memory phenotype and expressed high levels of PD-1, ICOS, HLA-DR, CXCR3 and CXCR5. Moreover, increased TIGIT CD4 T cell frequency correlated with the frequency of PD-1 CD4 T cells (r = 0.4705: = 0.0043) and circulating levels of ACPA and RF. We also identified a decreased frequency of CD27+IgD- switched memory B cells in RA patients ( < 0.01), while increased frequency of TIGIT+ CD4 T cells in FDR correlated with the frequency of PD1PTEN B cells (r = 0.6838, = 0.0004) and autoantibody positivity ( = 0.01).
We demonstrate TIGIT as a distinct CD4 T cell marker for differentiating aAb- FDR from aAb+FDR and might play a critical role in regulating T and B cell crosstalk in preclinical RA.
尽管免疫细胞失调是类风湿关节炎（RA）发病前的一个重要事件，但临床前 RA 中的 T 细胞和 B 细胞表型了解较少。本研究旨在描述 RA 患者及其自身抗体（aAb）阴性和阳性一级亲属（FDR）中的 T 细胞和 B 细胞群体。
从 aAb-（n=25）、aAb+ FDR（n=10）和 RA 患者（n=13）的预定就诊时收集冷冻保存的外周血单核细胞（PBMCs），并用优化的抗体鸡尾酒对其进行解冻和染色，根据特定的 13 色 T 或 B 细胞面板进行免疫表型分析。使用 Cytoflex LX（贝克曼库尔特）流式细胞仪进行免疫荧光分析，使用 FlowJo 软件分析免疫细胞群体的频率。
多色流式细胞术实验发现，与 aAb- FDR 相比，aAb+ FDR 和 RA 患者循环淋巴细胞中的 TIGIT 表达增加（P<0.01）。这些 TIGIT T 细胞表现出记忆表型，并表达高水平的 PD-1、ICOS、HLA-DR、CXCR3 和 CXCR5。此外，TIGIT CD4 T 细胞频率的增加与 PD-1 CD4 T 细胞频率（r = 0.4705： = 0.0043）和循环 ACPA 和 RF 水平相关。我们还发现 RA 患者中 CD27+IgD- 记忆 B 细胞的频率降低（<0.01），而 FDR 中 TIGIT+ CD4 T 细胞频率的增加与 PD1PTEN B 细胞频率（r = 0.6838， = 0.0004）和自身抗体阳性（ = 0.01）相关。
我们证明 TIGIT 是区分 aAb- FDR 和 aAb+FDR 的独特 CD4 T 细胞标志物，并且可能在调节临床前 RA 中的 T 和 B 细胞串扰中发挥关键作用。
