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http://dx.doi.org/10.14348/molcells.2015.2331

Life of T Follicular Helper Cells  

Suh, Woong-Kyung (Clinical Research Institute of Montreal (IRCM), University of Montreal, and McGill University)
Abstract
Antibodies are powerful defense tools against pathogens but may cause autoimmune diseases when erroneously directed toward self-antigens. Thus, antibody producing cells are carefully selected, refined, and expanded in a highly regulated microenvironment (germinal center) in the peripheral lymphoid organs. A subset of T cells termed T follicular helper cells (Tfh) play a central role in instructing B cells to form a repertoire of antibody producing cells that provide life-long supply of high affinity, pathogenspecific antibodies. Therefore, understanding how Tfh cells arise and how they facilitate B cell selection and differentiation during germinal center reaction is critical to improve vaccines and better treat autoimmune diseases. In this review, I will summarise recent findings on molecular and cellular mechanisms underlying Tfh generation and function with an emphasis on T cell costimulation.
Keywords
antibody; costimulation; germinal center; T follicular helper;
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