College of Veterinary Medicine, Hebei Agricultural University, Baoding 071000, China.
Int J Mol Sci. 2024 Oct 9;25(19):10849. doi: 10.3390/ijms251910849.
Virus-like particles (VLPs) have been studied and used as vaccines to control foot-and-mouth disease (FMD). Mast cells (MCs) express various pattern recognition receptors that recognize pathogens and secrete numerous cytokines to initiate and modulate immune responses. Our previous study showed that bone marrow-derived mast cells (BMMCs) can recognize foot-and-mouth disease virus-like particles (FMDV-VLPs) to differentially express various cytokines and that histone acetylation can regulate the cytokines secreted during BMMC recognition of FMDV-VLPs. To demonstrate the role of DNA methylation in this response process, BMMCs that recognize FMDV-VLPs were treated with azacytidine (5-AZA), an inhibitor of DNA methylation transferase. We prepared FMDV-VLPs as described previously and cultured the BMMCs. The transcription and expression of key cytokines and transcription factors were determined using real-time quantitative PCR (RT-qPCR) and Western blotting. Results showed that pre-treatment with AZA resulted in the increased transcription and expression of tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-13, and IL-10, while the changes in IL-13 transcription and IL-6 expression were irrelevant to mannose receptors (MRs). Furthermore, analysis of the transcription factors indicated that both the transcription and expression of nuclear factor-kappa B (NF-κB) increased significantly in the AZA pre-treated group, indicating that DNA methylation may also regulate NF-κB expression to modulate TNF-α, IL-13, and IL-6. However, pre-treatment with AZA did not alter the expression of microphthalmia-associated transcription factor (MITF) or GATA-2. All the data demonstrate that DNA methylation negatively regulates the transcription and expression of TNF-α, IL-13, IL-10, and IL-6 secreted by recognizing FMDV-VLPs. These results provide new ideas for the mast cell-based design of more effective vaccine adjuvants and targeted therapies in the future.
病毒样颗粒（VLPs）已被研究并用作控制口蹄疫（FMD）的疫苗。肥大细胞（MCs）表达多种模式识别受体，可识别病原体并分泌多种细胞因子，以启动和调节免疫反应。我们之前的研究表明，骨髓来源的肥大细胞（BMMCs）可以识别口蹄疫病毒样颗粒（FMDV-VLPs），从而差异表达各种细胞因子，并且组蛋白乙酰化可以调节 BMMC 识别 FMDV-VLPs 时分泌的细胞因子。为了证明 DNA 甲基化在该反应过程中的作用，用 DNA 甲基转移酶抑制剂 5-氮杂胞苷（5-AZA）处理识别 FMDV-VLPs 的 BMMC。我们如前所述制备 FMDV-VLPs 并培养 BMMC。使用实时定量 PCR（RT-qPCR）和 Western 印迹法测定关键细胞因子和转录因子的转录和表达。结果表明，AZA 预处理导致肿瘤坏死因子-α（TNF-α）、白细胞介素（IL）-6、IL-13 和 IL-10 的转录和表达增加，而 IL-13 转录和 IL-6 表达的变化与甘露糖受体（MRs）无关。此外，转录因子分析表明，AZA 预处理组 NF-κB 的转录和表达均显著增加，表明 DNA 甲基化也可能调节 NF-κB 表达，从而调节 TNF-α、IL-13 和 IL-6。然而，AZA 预处理并未改变小眼畸形相关转录因子（MITF）或 GATA-2 的表达。所有数据表明，DNA 甲基化负调控识别 FMDV-VLPs 后分泌的 TNF-α、IL-13、IL-10 和 IL-6 的转录和表达。这些结果为基于肥大细胞的设计提供了新的思路，未来可为更有效的疫苗佐剂和靶向治疗提供更多选择。
