Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, China; Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha Duxact Biotech Co., Ltd., Changsha, China; Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha, China; Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, China; National Clinical Research Center for Geriatric Disorders, Changsha, China.
Hunan Key Laboratory for Bioanalysis of Complex Matrix Samples, Changsha Duxact Biotech Co., Ltd., Changsha, China.
J Ethnopharmacol. 2024 Nov 15;334:118523. doi: 10.1016/j.jep.2024.118523. Epub 2024 Jul 4.
HLA-B35:01 has been identified as a risk allele for Polygonum multiflorum Thunb.-induced liver injury (PMLI). However, the immune mechanism underlying HLA-B35:01-mediated PMLI remains unknown.
To characterize the immune mechanism of HLA-B*35:01-mediated PMLI.
Components of P. multiflorum (PM) bound to the HLA-B35:01 molecule was screened by immunoaffinity chromatography. Both wild-type mice and HLA-B35:01 transgenic (TG) mice were treated with emodin. The levels of transaminases, histological changes and T-cell response were assessed. Splenocytes from emodin-treated mice were isolated and cultured in vitro. Phenotypes and functions of T cells were characterized upon drug restimulation using flow cytometry or ELISA. Emodin-pulsed antigen-presenting cells (APCs) or glutaraldehyde-fixed APCs were co-cultured with splenocytes from emodin-treated transgenic mice to detect their effect on T-cell activation.
Emodin, the main component of PM, could non-covalently bind to the HLA-B*35:01-peptide complexes. TG mice were more sensitive to emodin-induced immune hepatic injury, as manifested by elevated aminotransferase levels, infiltration of inflammatory cells, increased percentage of CD8+T cells and release of effector molecules in the liver. However, these effects were not observed in wild-type mice. An increase in percentage of T cells and the levels of interferon-γ, granzyme B, and perforin was detected in emodin-restimulated splenocytes from TG mice. Anti-HLA-I antibodies inhibited the secretion of these effector molecules induced by emodin. Mechanistically, emodin-pulsed APCs failed to stimulate T cells, while fixed APCs in the presence of emodin could elicit the secretion of T cell effector molecules.
The HLA-B*35:01-mediated CD8 T cell reaction to emodin through the P-I mechanism may contribute to P. multiflorum-induced liver injury.
HLA-B35:01 已被确定为何首乌诱导肝损伤 (PMLI) 的风险等位基因。然而，HLA-B35:01 介导的 PMLI 背后的免疫机制尚不清楚。
表征 HLA-B*35:01 介导的 PMLI 的免疫机制。
通过免疫亲和层析筛选与 HLA-B35:01 分子结合的何首乌成分。用大黄素处理野生型和 HLA-B35:01 转基因 (TG) 小鼠。评估转氨酶水平、组织学变化和 T 细胞反应。从大黄素处理的小鼠中分离脾细胞，并在体外培养。通过流式细胞术或 ELISA 检测药物再刺激后 T 细胞的表型和功能。将大黄素脉冲抗原呈递细胞 (APC) 或戊二醛固定 APC 与来自大黄素处理的转基因小鼠的脾细胞共培养，以检测它们对 T 细胞激活的影响。
何首乌的主要成分大黄素可与 HLA-B*35:01-肽复合物非共价结合。TG 小鼠对大黄素诱导的免疫性肝损伤更为敏感，表现为转氨酶水平升高、炎症细胞浸润增加、CD8+T 细胞比例增加以及肝脏中效应分子的释放。然而，在野生型小鼠中没有观察到这些作用。在来自 TG 小鼠的大黄素再刺激的脾细胞中检测到 T 细胞比例增加以及干扰素-γ、颗粒酶 B 和穿孔素的水平升高。抗 HLA-I 抗体抑制了大黄素诱导的这些效应分子的分泌。在机制上，大黄素脉冲 APC 不能刺激 T 细胞，而在存在大黄素的情况下固定 APC 可以引发 T 细胞效应分子的分泌。
通过 P-I 机制，HLA-B*35:01 介导的对大黄素的 CD8 T 细胞反应可能导致何首乌引起的肝损伤。
