MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu, People's Republic of China.
Vet Res. 2020 Nov 17;51(1):138. doi: 10.1186/s13567-020-00864-z.
Dendritic cells (DCs) play a pivotal role to amplify antigen-specific immune responses. Antigens that sensitize T cells via antigen-presentation by DCs could enhance the capacity of host immunity to fight infections. In this study, we tested the immunogenic profiles of chicken DCs towards Glyceraldehyde-3-phosphate dehydrogenase from Eimeria acervulina (EaGAPDH). Immunoblot analysis showed that recombinant EaGAPDH (rEaGAPDH) protein was successfully recognized by rat sera generated against rEaGAPDH. Interaction and internalisation of rEaGAPDH by chicken splenic-derived DCs (chSPDCs) was confirmed by immunofluorescence analysis. Flow cytometry revealed that chSPDCs upregulated MHCII, CD1.1, CD11c, CD80, and CD86 cell-surface markers. Moreover, mRNA expressions of DC maturation biomarkers (CCL5, CCR7, and CD83) and TLR signalling genes (TLR15 and MyD88) were also upregulated whereas those of Wnt signalling were non-significant compared to negative controls. rEaGAPDH treatment induced IL-12 and IFN-γ secretion in chSPDCs but had no effect on IL-10 and TGF-β. Likewise, DC-T cell co-culture promoted IFN-γ secretion and the level of IL-4 was unaffected. Proliferation of T cells and their differentiation into CD3/CD4 T cells were triggered in chSPDCs-T cells co-culture system. Taken together, rEaGAPDH could promote Th1 polarization by activating both host DCs and T cells and sheds new light on the role of this important molecule which might contribute to the development of new DCs-based immunotherapeutic strategies against coccidiosis.
树突状细胞 (DCs) 在放大抗原特异性免疫反应方面发挥着关键作用。通过 DC 进行抗原呈递使 T 细胞致敏的抗原可以增强宿主免疫对抗感染的能力。在这项研究中，我们测试了鸡 DC 对柔嫩艾美耳球虫甘油醛-3-磷酸脱氢酶 (EaGAPDH) 的免疫原性特征。免疫印迹分析表明，重组 EaGAPDH (rEaGAPDH) 蛋白成功地被针对 rEaGAPDH 的大鼠血清识别。免疫荧光分析证实了 rEaGAPDH 与鸡脾源性 DC (chSPDCs) 的相互作用和内化。流式细胞术显示，chSPDCs 上调了 MHCII、CD1.1、CD11c、CD80 和 CD86 细胞表面标志物。此外，与阴性对照相比，DC 成熟生物标志物 (CCL5、CCR7 和 CD83) 和 TLR 信号基因 (TLR15 和 MyD88) 的 mRNA 表达也上调，而 Wnt 信号的表达则没有显著变化。rEaGAPDH 处理诱导 chSPDCs 分泌 IL-12 和 IFN-γ，但对 IL-10 和 TGF-β 没有影响。同样，DC-T 细胞共培养促进 IFN-γ 分泌，而 IL-4 水平不受影响。在 chSPDCs-T 细胞共培养系统中，T 细胞增殖并分化为 CD3/CD4 T 细胞。综上所述，rEaGAPDH 通过激活宿主 DCs 和 T 细胞来促进 Th1 极化，为这种重要分子的作用提供了新的认识，这可能有助于开发针对球虫病的新的基于 DC 的免疫治疗策略。
