PDF(Pubmed)
Abstract：
Enterotoxigenic Escherichia coli (ETEC) causes severe diarrhea in piglets. The current primary approach for ETEC prevention and control relies on antibiotics, as few effective vaccines are available. Consequently, an urgent clinical demand exists for developing an effective vaccine to combat this disease. Here, we utilized food-grade Lactococcus lactis NZ3900 and expression plasmid pNZ8149 as live vectors, together with the secreted expression peptide Usp45 and the cell wall non-covalent linking motif LysM, to effectively present the mutant LTA subunit, the LTB subunit of heat-labile enterotoxin, and the FaeG of F4 pilus on the surface of recombinant lactic acid bacteria (LAB). Combining three recombinant LAB as a live vector oral vaccine, we assessed its efficacy in preventing F4+ ETEC infection. The results demonstrate that oral immunization conferred effective protection against F4+ ETEC infection in mice and piglets lacking maternal antibodies during weaning. Sow immunization during late pregnancy generated significantly elevated antibodies in colostrum, which protected piglets against F4+ ETEC infection during lactation. Moreover, booster immunization on piglets during lactation significantly enhanced their resistance to F4+ ETEC infection during the weaning stage. This study highlights the efficacy of an oral LAB vaccine in preventing F4+ ETEC infection in piglets by combining the sow immunization and booster immunization of piglets, providing a promising vaccination strategy for future prevention and control of ETEC-induced diarrhea in piglets.
摘要：
产肠毒素大肠杆菌（ETEC）导致仔猪严重腹泻。目前ETEC预防和控制的主要方法依赖于抗生素，有效的疫苗很少。因此,临床上迫切需要开发一种有效的疫苗来对抗这种疾病。这里,我们利用食品级乳酸乳球菌NZ3900和表达质粒pNZ8149作为活载体，连同分泌的表达肽Usp45和细胞壁非共价连接基序LysM，为了有效地呈现突变的LTA亚基，不耐热肠毒素的LTB亚基，和重组乳酸菌（LAB）表面F4菌毛的FaeG。结合三种重组LAB作为口服疫苗的活载体，我们评估了其预防F4+ETEC感染的疗效.结果表明，口服免疫在断奶期间缺乏母体抗体的小鼠和仔猪中提供了针对F4ETEC感染的有效保护。妊娠晚期母猪免疫产生显著升高的初乳抗体，在哺乳期间保护仔猪免受F4+ETEC感染。此外，哺乳期间仔猪的加强免疫显着增强了其在断奶阶段对F4ETEC感染的抵抗力。这项研究强调了口服LAB疫苗通过结合母猪免疫和仔猪加强免疫在预防仔猪F4ETEC感染中的功效，为将来预防和控制仔猪ETEC引起的腹泻提供了有希望的疫苗接种策略。
