Edwardsiella ictaluri causes enteric septicemia of catfish. Our group developed two E. ictaluri live attenuated vaccines (LAVs). However, their effects on the innate functions of catfish B cells are still unexplored. We evaluated phagocytosis and killing of wild-type (WT) E. ictaluri opsonized with sera from vaccinated fish and the survival of B cells exposed to E. ictaluri strains. We assessed phagocytosis of the opsonized WT at 30 °C and 4 °C. B cells killed the internalized E. ictaluri opsonized with sera from vaccinated fish with LAVs more efficiently than other groups at 30 °C. However, catfish B cells were unable to destroy E. ictaluri at 4 °C. Furthermore, E. ictaluri opsonized with serum from fish exposed to WT induce apoptosis and decreased live B cells numbers. Results indicate that opsonization of E. ictaluri with sera from vaccinated fish enhanced phagocytosis and killing activity in B cells and inhibited apoptotic changes in the infected B cells.

中文翻译：

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减毒爱德华氏菌 ictaluri 疫苗增强了鲶鱼 B 细胞的保护性先天免疫反应。

Edwardsiella ictaluri 引起鲶鱼的肠道败血症。我们小组开发了两种 E. ictaluri 减毒活疫苗 (LAV)。然而，它们对鲶鱼 B 细胞先天功能的影响仍有待探索。我们评估了野生型 (WT) E. ictaluri 的吞噬作用和杀灭作用，该 E. ictaluri 用来自接种鱼的血清调理，以及暴露于 E. ictaluri 菌株的 B 细胞的存活。我们评估了调理 WT 在 30°C 和 4°C 下的吞噬作用。在 30 °C 下，B 细胞比其他组更有效地杀死用 LAV 疫苗接种鱼的血清调理的内化 E. ictaluri。然而，鲶鱼 B 细胞在 4 °C 时无法破坏 E. ictaluri。此外，用来自暴露于 WT 的鱼的血清调理的 E. ictaluri 诱导细胞凋亡并减少活 B 细胞数量。结果表明 E.