AUTHOR=Liu Haofei , Xu Wenwen , Yu Qinghua , Yang Qian 

TITLE=4,4′-Diaponeurosporene-Producing Bacillus subtilis Increased Mouse Resistance against Salmonella typhimurium Infection in a CD36-Dependent Manner

JOURNAL=Frontiers in Immunology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2017.00483

DOI=10.3389/fimmu.2017.00483

ISSN=1664-3224

ABSTRACT=<p>Deficient mucosal innate immunity is a hallmark of infectious diarrhea, such as <italic>Salmonella typhimurium</italic> (<italic>S</italic>. <italic>typhimurium</italic>)-induced gastroenteritis. Here, we report that oral administration of a 4,4′-diaponeurosporene-producing <italic>Bacillus subtilis</italic> (B.s-Dia) could improve mice mucosal immunity, as showed by an increased resistance against <italic>S. typhimurium</italic> infection. Intragastric administration of B.s-Dia for 7 days could increase the secretion of CCL20 by intestinal epithelial cells (IECs) and then recruit more dendritic cells. Meanwhile, the number of CD8αα<sup>+</sup> intraepithelial lymphocytes, which play a critical role in downregulating immune responses, was also reduced, probably as a consequence of the decrease of IEC-derived TGFβ. Further study showed that CD36 played a critical role in B.s-Dia-induced immune enhancement, as blocking CD36 signal with a specific antagonist, sulfo-N-succinimidyl oleate, led to the inability of B.s-Dia to enhance mucosal innate immunity.</p>