AUTHOR=Gong Fang , Zheng Ting , Zhou Pengcheng 

TITLE=T Follicular Helper Cell Subsets and the Associated Cytokine IL-21 in the Pathogenesis and Therapy of Asthma

JOURNAL=Frontiers in Immunology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2019.02918

DOI=10.3389/fimmu.2019.02918

ISSN=1664-3224

ABSTRACT=<p>For many decades, T helper 2 (T<sub>H</sub>2) cells have been considered to predominantly regulate the pathogenic manifestations of allergic asthma, such as IgE-mediated sensitization, airway hyperresponsiveness, and eosinophil infiltration. However, recent discoveries have significantly shifted our understanding of asthma from a simple T<sub>H</sub>2 cell-dependent disease to a heterogeneous disease regulated by multiple T cell subsets, including T follicular helper (T<sub>FH</sub>) cells. T<sub>FH</sub> cells, which are a specialized cell population that provides help to B cells, have attracted intensive attention in the past decade because of their crucial role in regulating antibody response in a broad range of diseases. In particular, T<sub>FH</sub> cells are essential for IgE antibody class-switching. In this review, we summarize the recent progress regarding the role of T<sub>FH</sub> cells and their signature cytokine interleukin (IL)-21 in asthma from mouse studies and clinical reports. We further discuss future therapeutic strategies to treat asthma by targeting T<sub>FH</sub> cells and IL-21.</p>