Fungal immunomodulatory protein (FIP) is one of the bioactive compounds of edible mushrooms, which has been shown to trigger type 1 T helper (Th1) pathway activation in research with mice. This study was designated to assess immunomodulatory effects of recombinant FIP-Flammulina velutipes (rFIP-fve) on swine and the protective efficacy against PRRSV infection. In the in vitro evaluations, rFIP-fve significantly triggered up-regulation of IL-2 and IFN-γ mRNA in porcine PBMCs and stimulated natural killer cytotoxicity. Porcine pulmonary alveolar macrophages (PAMs) treated with rFIP-fve showed prolonged life times, up-regulation of both MHC I and II molecules and enhanced abilities to present antigen. In the in vivo trial, two doses of 2 mg rFIP-fve significantly reduced drops in the CD4/CD8 ratio after PRRSV challenge, and the cytokine mRNA profile of PBMC revealed a tendency of IFN-γ up-regulation and a decrease in IL-10 in the rFIP-treated group. Moreover, administration of rFIP-fve also decreased the PRRSV viremia with 1 log10 in titer (p = 0.07) and alleviated the severity of clinical signs after PRRSV challenge. Conclusively, these results illustrate the in vitro and in vivo immunological changes of rFIP-fve administered to pigs and reveal its potential to be used as an immunomodulatory therapeutic against PRRSV infection.

中文翻译：

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真菌免疫调节蛋白促进猪针对猪繁殖与呼吸综合征病毒感染的免疫反应的功效。


真菌免疫调节蛋白 (FIP) 是食用蘑菇的生物活性化合物之一，在小鼠研究中已显示其可触发 1 型 T 辅助细胞 (Th1) 通路激活。本研究旨在评估重组 FIP-金针菇 (rFIP-fve) 对猪的免疫调节作用以及对 PRRSV 感染的保护作用。在体外评估中，rFIP-fve 显着引发猪 PBMC 中 IL-2 和 IFN-γ mRNA 的上调，并刺激自然杀伤细胞毒性。用 rFIP-fve 处理的猪肺泡巨噬细胞 (PAM) 显示出寿命延长、MHC I 和 II 分子上调以及呈递抗原的能力增强。在体内试验中，两剂 2 mg rFIP-fve 显着降低了 PRRSV 攻击后 CD4/CD8 比值的下降，PBMC 的细胞因子 mRNA 谱显示 IFN-γ 上调和 IL-2 下降的趋势。 rFIP 治疗组中有 10 例。此外，给予 rFIP-fve 还可以降低 PRRSV 病毒血症，滴度为 1 log10 (p = 0.07)，并减轻 PRRSV 攻击后临床症状的严重程度。总之，这些结果说明了给予猪的 rFIP-fve 的体外和体内免疫学变化，并揭示了其用作抗 PRRSV 感染的免疫调节疗法的潜力。