AUTHOR=Yang Quan , Qu Jiale , Jin Chenxi , Feng Yuanfa , Xie Shihao , Zhu Jinxin , Liu Gaoshen , Xie Hongyan , Qiu Huaina , Qi Yanwei , Mu Jianbing , Huang Jun 

TITLE=Schistosoma japonicum Infection Promotes the Response of Tfh Cells Through Down-Regulation of Caspase-3–Mediating Apoptosis

JOURNAL=Frontiers in Immunology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2019.02154

DOI=10.3389/fimmu.2019.02154

ISSN=1664-3224

ABSTRACT=<p>CD4<sup>+</sup> T follicular helper (Tfh) cells, a new subset of immune cells, have been demonstrated to be involved in granulomatous responses to <italic>Schistosoma japonicum (S. japonicum)</italic> infection. However, the role and underlying mechanisms of Tfh cell aggregation in <italic>S. japonicum</italic> infection remain incompletely understood. In this study, we provide evidence that <italic>S. japonicum</italic> infection enhances the accumulation of Tfh cells in the spleen, lymph nodes, and peripheral blood of C57BL/6 mice. Infection-induced Tfh cells exhibited more potent effects directly on B cell responses than the control Tfh cells (<italic>P</italic> &lt; 0.05). Furthermore, reduced apoptosis of Tfh cells was found both in <italic>S. japonicum</italic> infected mice and in soluble egg antigen (SEA) treated Tfh cells (<italic>P</italic> &lt; 0.05). Mechanistic studies reveal that caspase-3 is the primary drivers of down-regulated apoptotic Tfh cell death in <italic>S. japonicum</italic> infection. In summary, this study demonstrates that Tfh cell accumulation might have an impact on the generation of immune responses in <italic>S. japonicum</italic> infection, and caspase-3 signaling mediated apoptosis down-regulation might responsible for the accumulation of Tfh cell in this course.</p>