Mizuno Hiroya, Tomotsune Kae, Islam Md Aminul, Funabashi Ryutaro, Albarracin Leonardo, Ikeda-Ohtsubo Wakako, Aso Hisashi, Takahashi Hideki, Kimura Katsunori, Villena Julio, Sasaki Yasuko, Kitazawa Haruki
Food and Feed Immunology Group, Laboratory of Animal Products Chemistry, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan.
Livestock Immunology Unit, International Education and Research Center for Food and Agricultural Immunology (CFAI), Graduate School of Agricultural Science, Tohoku University, Sendai, Japan.
Front Microbiol. 2020 May 19;11:894. doi: 10.3389/fmicb.2020.00894. eCollection 2020.
It was reported that exopolysaccharides (EPSs) from lactobacilli are able to differentially modulate mucosal antiviral immunity. Although research has described the ability of EPSs derived from to modulate the mucosal immune system, their impact on antiviral immunity was less explored. In this work, we investigated the capacity of the EPS-producing ST538 to modulate the innate antiviral immune response triggered by the activation of the Toll-like receptor 3 (TLR3) in porcine intestinal epitheliocytes (PIE cells). Moreover, in order to study the immunomodulatory potential of ST538 EPS, we successfully developed two mutant strains through the knockout of the or genes. High-performance liquid chromatography and scanning electron microscopy studies demonstrated that the wild type (WT) strain produced as high as 595 μg/ml of EPS in the skim milk medium, while none of the mutant strains ( Δ and Δ) were able to produce EPS. Studies in PIE cells demonstrated that the EPS of ST538 is able to significantly improve the expression of interferon β (), interleukin 6 (), and C-X-C motif chemokine 10 () in response to TLR3 stimulation. The role of EPS in the modulation of antiviral immune response in PIE cells was confirmed by comparative studies of cell free culture supernatants and fermented skim milks obtained from Δ and Δ. These results suggest that ST538 could be used as an immunobiotic strain for the development of new immunologically functional foods, which might contribute to improve resistance against viral infections.
据报道，来自乳酸菌的胞外多糖（EPSs）能够差异性地调节黏膜抗病毒免疫。尽管已有研究描述了源自[具体来源未给出]的EPSs调节黏膜免疫系统的能力，但其对抗病毒免疫的影响却较少被探究。在本研究中，我们调查了产EPS的[菌株名称未给出]ST538调节猪肠道上皮细胞（PIE细胞）中由Toll样受体3（TLR3）激活引发的先天性抗病毒免疫反应的能力。此外，为了研究[菌株名称未给出]ST538 EPS的免疫调节潜力，我们通过敲除[基因名称未给出]或[基因名称未给出]基因成功开发了两种突变菌株。高效液相色谱和扫描电子显微镜研究表明，野生型（WT）菌株在脱脂乳培养基中产生的EPS高达595μg/ml，而突变菌株（[菌株名称未给出]Δ[基因名称未给出]和[菌株名称未给出]Δ[基因名称未给出]）均无法产生EPS。对PIE细胞的研究表明，[菌株名称未给出]ST538的EPS能够显著提高在TLR3刺激下干扰素β（IFN-β）、白细胞介素6（IL-6）和C-X-C基序趋化因子10（CXCL10）的表达。通过对来自[菌株名称未给出]Δ[基因名称未给出]和[菌株名称未给出]Δ[基因名称未给出]的无细胞培养上清液和发酵脱脂乳的比较研究，证实了EPS在PIE细胞抗病毒免疫反应调节中的作用。这些结果表明，[菌株名称未给出]ST538可作为一种免疫益生菌菌株用于开发新型免疫功能性食品，这可能有助于提高对病毒感染的抵抗力。
