Ammon Tim, Zeiträg Julia, Mayr Vanessa, Benedicic Manuela, Holthoff Hans-Peter, Ungerer Martin
ISAR Bioscience GmbH, Planegg, Germany.
ACR Open Rheumatol. 2025 Jan;7(1):e11785. doi: 10.1002/acr2.11785.
Rheumatoid arthritis (RA) is characterized by circulating anti-cyclic citrullinated peptide (CCP) autoantibodies (ACPAs), resulting in inflammation of the joints and other organs. We have established novel assays to assess immune cell subpopulations, including citrullinated antigen-specific (CAS) autoreactive B and T lymphocytes, in patients with RA.
We found that activated CD25 T cells were markedly increased in patients with RA compared to healthy controls. Novel combinations of major histocompatibility complex class II citrulline epitope tetramers were developed, which enabled robust detection of CAS T cells and showed increases of CAS-naive T helper cells, Th1.17 cells, CAS total circulating T follicular helper (cTfh) cells, and cTfh1 cells in ACPA patients with RA. In addition, an innovative assay using dual labeling with CCP-biotin probes allowed for reproducible identification of primary CAS B cells after enrichment with advantages over existing detection methods. Furthermore, patient-derived immune cells were successfully expanded. Primary RA B cells were successfully cultured on novel feeder cell lines, whereas T cells were expanded ex vivo in the presence of interleukin-2 and citrullinated peptides, and subsequent alterations in cell frequencies were assessed.
Novel assays were established to reliably detect CAS T and B cells in patients with RA, and specific CAS-naive T helper cells, Th1.17 cells, cTfh cells, and cTfh1 cells were observed more frequently in RA. Based on these results, new coculture systems of disease-relevant cells are developed to simulate human secondary lymphoid tissues ex vivo. This technology will serve as a platform to identify therapies that modulate disease-specific immune cells.
类风湿关节炎（RA）的特征是循环中的抗环瓜氨酸肽（CCP）自身抗体（ACPA），导致关节和其他器官的炎症。我们建立了新的检测方法来评估RA患者的免疫细胞亚群，包括瓜氨酸化抗原特异性（CAS）自身反应性B和T淋巴细胞。
我们发现，与健康对照相比，RA患者中活化的CD25 T细胞显著增加。开发了主要组织相容性复合体II类瓜氨酸表位四聚体的新组合，能够可靠地检测CAS T细胞，并显示在ACPA阳性的RA患者中，未接触过抗原的CAS辅助性T细胞、Th1.17细胞、CAS循环滤泡辅助性T（cTfh）细胞总数及cTfh1细胞增加。此外，一种使用CCP生物素探针双重标记的创新检测方法，在富集后能够可重复地鉴定原发性CAS B细胞，优于现有检测方法。此外，成功扩增了患者来源的免疫细胞。原发性RA B细胞在新型饲养细胞系上成功培养，而T细胞在白细胞介素-2和瓜氨酸化肽存在的情况下离体扩增，并评估随后细胞频率的变化。
建立了新的检测方法以可靠地检测RA患者中的CAS T和B细胞，并且在RA中更频繁地观察到特定的未接触过抗原的CAS辅助性T细胞、Th1.17细胞、cTfh细胞和cTfh1细胞。基于这些结果，开发了与疾病相关细胞的新共培养系统，以在体外模拟人类二级淋巴组织。这项技术将作为一个平台来识别调节疾病特异性免疫细胞的疗法。
