College of Animal Science and Technology, Shihezi University, Shihezi, Xinjiang 832003, P.R. China.
College of Biology and Food, Shangqiu Normal University, Shangqiu, Henan 476000, P.R. China.
Mol Med Rep. 2022 Jul;26(1). doi: 10.3892/mmr.2022.12740. Epub 2022 May 20.
Outer membrane protein 25 (OMP25) is involved in virulence and serves an important role in pathogenesis during infection. However, the protein interacting with OMP25 in host cells remains to be elucidated. The present study constructed a cDNA library from 16M‑infected human placenta trophoblastic cells (HPT‑8) and identified and confirmed the interaction between OMP25 and ferritin heavy polypeptide 1 (FTH1) of HPT‑8 using yeast two‑hybrid and co‑immunoprecipitation technologies. The expression of Toll‑like receptor (TLR)4, myeloid differentiation primary response protein MyD88 (MyD88) mRNA and inflammatory factors was detected by RNA interference. The results showed that OMP25 interacted with FTH1. Subsequently, TLR4 and MyD88 mRNA expression levels and inflammatory factors, such as nitric oxide, lactate dehydrogenase and TNF‑α, significantly increased after inserting OMP25 into the HPT‑8 cells. Notably, a low dose of OMP25 resulted in immunological protection, whereas high dose of OMP25 resulted in a cytotoxic effect on the HPT‑8 cells. It is suggested that OMP25 and FTH1 serve important roles in intracellular parasitism of and inhibition of expression.
外膜蛋白 25（OMP25）参与毒力，在感染期间的发病机制中起着重要作用。然而，与宿主细胞中的 OMP25 相互作用的蛋白质仍有待阐明。本研究从 16M 感染的人胎盘滋养层细胞（HPT-8）构建了 cDNA 文库，并使用酵母双杂交和共免疫沉淀技术鉴定和证实了 OMP25 与 HPT-8 的铁蛋白重链 1（FTH1）之间的相互作用。通过 RNA 干扰检测 Toll 样受体（TLR）4、髓样分化初级反应蛋白 MyD88（MyD88）mRNA 和炎症因子的表达。结果表明，OMP25 与 FTH1 相互作用。随后，将 OMP25 插入 HPT-8 细胞后，TLR4 和 MyD88 mRNA 表达水平以及炎症因子，如一氧化氮、乳酸脱氢酶和 TNF-α，显著增加。值得注意的是，低剂量的 OMP25 导致免疫保护，而高剂量的 OMP25 对 HPT-8 细胞产生细胞毒性作用。这表明 OMP25 和 FTH1 在寄生虫的细胞内寄生和抑制表达中起重要作用。
