Journal Article

IL‑17A + γδT cell activation via the HMGB1‑TLR2/4‑NF‑κB signaling pathways in biliary atresia

Tang, Shao-Tao, Hong, Mei, Yang, Ying, Zhou, Yun, Zhang, Jin-Xiang, Tang, Jing-Feng, Cao, Guo-Qing, Zhang, Xi, Rong, Li-Ying, Chi, Shui-Qing, Zhang, Meng-Xin

2026

Overview

IL-17A+ γδT cells are involved in biliary atresia (BA) inflammatory injury; however, the mechanism underlying their activation remains unclear. The present study aimed to elucidate the mechanism by which γδT cells are activated to secrete IL-17A in BA. Clinical samples from 27 patients with BA and 23 control individuals were collected and analyzed using reverse transcription-quantitative PCR (RT-qPCR), western blotting, ELISA, flow cytometry, Opal multiplex immunohistochemistry and immunohistochemistry. In addition, wild-type (WT) and Tcrδ−/− BA murine models were developed through infection with rhesus rotavirus (RRV) and assessed by RT-qPCR, western blotting, ELISA, flow cytometry, immunohistochemistry and hematoxylin and eosin staining. The release of high-mobility group box-1 (HMGB1) from RRV-infected biliary epithelial cells (BECs) and macrophages was investigated by ELISA and immunofluorescence confocal microscopy. In addition, co-culture systems of γδT cells with BECs or macrophages were established. The results revealed that the levels of hepatic IL-17A were higher in patients with BA, with γδT cells serving an important role in producing IL-17A. In the BA murine model, the IL-17A levels increased from day 3 to 14, and IL-17A+ γδT cells peaked on day 7. The Tcrδ−/− BA murine model exhibited lower IL-17A levels, improved liver and bile duct morphology, and lower BA incidence compared with in the WT BA murine model, which was reversed through adoptive transfer of murine IL-17A+ γδT cells. HMGB1, and Toll-like receptor (TLR)2 and 4 were upregulated in liver tissues from both patients with BA and the BA murine model. By contrast, hepatic IL-17A levels were decreased in the BA murine model treated with the HMGB1 inhibitor. In addition, HMGB1 was released from RRV-infected BECs or macrophages, and exogenous HMGB1 stimulation enhanced IL-17A production in γδT cells. The Tlr2−/− and Tlr4−/− γδT cell co-culture system inhibited IL-17A production and NF-κB activation, whereas NF-κB inhibition abolished HMGB1-induced IL-17A production in WT γδT cells. In conclusion, HMGB1 released from injured BECs or macrophages may activate IL-17A+ γδT cells to mediate BA inflammatory injury via the HMGB1-TLR2/4-NF-κB pathways. The present study was registered with the Chinese Clinical Trial Registry (registration ID: ChiCTR2000039619; registered November 3, 2020).

• Publisher: Spandidos Publications