DataSheet_2_Paired Rheumatoid Arthritis Synovial Biopsies From Small and Large Joints Show Similar Global Transcriptomic Patterns With Enrichment of Private Specificity TCRB and TCR Signaling Pathways.pdf

ObjectivesWe explored histological and transcriptomic profiles of paired synovial biopsies from rheumatoid arthritis (RA) patients, in order to assess homogeneity in synovial tissue at the individual level.
MethodsSynovial biopsies were performed simultaneously in one small and one large joint per patient using needle-arthroscopy for the knee and ultrasound-guided biopsy for the hand or wrist. Synovium from individuals with osteoarthritis was used as controls. Paraffin-embedded samples were stained for CD3, CD20, and CD68. Total RNA was hybridized on high-density microarrays. TCRB variable sequences were obtained from synovial and blood RNA samples.
ResultsTwenty paired biopsies from 10 RA patients with active disease were analyzed. Semi-quantification of histological markers showed a positive correlation for synovial hyperplasia, inflammatory infiltrates and CD3-positive T cells between pairs. Pairwise comparison of transcriptomic profiles showed similar expression of RA-related molecular pathways (TCR signaling, T cell costimulation and response to TNFα). T cells clonotypes were enriched in all but one joints compared to blood, regardless of the magnitude of T cell infiltration. Enriched clonotypes were shared between pairs (23–100%), but this was less the case in pairs of joints displaying weaker T cell signatures and more pronounced germinal center-like transcriptomic profiles.
ConclusionCellular and molecular alterations in RA synovitis are similar between small and large joints from the same patient. Interindividual differences in magnitude of T cell infiltrates and distribution of enriched T cell clonotypes support the concept of distinct synovial pathotypes in RA that are associated with systemic versus local antigen-driven activation of T cells.

研究目标：本研究旨在探究类风湿关节炎（rheumatoid arthritis, RA）患者配对滑膜活检样本的组织学与转录组学特征，以评估个体水平滑膜组织的均一性。
研究方法：本研究对每位患者的1个小关节与1个大关节同时进行滑膜活检：膝关节采用针式关节镜操作，手或腕关节采用超声引导下活检。以骨关节炎（osteoarthritis）患者的滑膜组织作为对照。将石蜡包埋样本进行CD3、CD20及CD68染色。总RNA在高密度微阵列上进行杂交。从滑膜与血液RNA样本中获取TCRB可变区序列。
研究结果：本研究共分析了10例活动性类风湿关节炎患者的20份配对活检样本。组织学标志物的半定量分析显示，配对样本间的滑膜增生、炎性浸润及CD3阳性T细胞水平呈正相关。转录组谱的两两比较显示，类风湿关节炎相关分子通路（TCR信号通路、T细胞共刺激及TNFα应答）的表达模式相似。与血液样本相比，除1个关节外，其余所有关节的T细胞克隆型均富集，且与T细胞浸润程度无关。富集的克隆型在配对样本间的共享比例为23%~100%，但在T细胞特征较弱且生发中心样转录组特征更显著的关节配对中，这种共享比例更低。
研究结论：同一患者的小关节与大关节的类风湿关节炎滑膜炎的细胞与分子改变具有相似性。不同个体间的T细胞浸润程度及富集T细胞克隆型分布存在差异，这支持类风湿关节炎存在不同滑膜病理型别的观点，这些病理型别分别与T细胞的全身性抗原驱动活化及局部抗原驱动活化相关。