CD4+ T Follicular Helper Cells in Human Tonsils and Blood Are Clonally Convergent but Divergent from Non-Tfh CD4+ Cells
Elena Brenna, Alexey N Davydov, Kristin Ladell, James E McLaren, Paolo Bonaiuti, Maria Metsger, James D Ramsden, Sarah C Gilbert, Teresa Lambe, David A Price, Suzanne L Campion, Dmitriy M Chudakov, Persephone Borrow, Andrew J McMichael, Elena Brenna, Alexey N Davydov, Kristin Ladell, James E McLaren, Paolo Bonaiuti, Maria Metsger, James D Ramsden, Sarah C Gilbert, Teresa Lambe, David A Price, Suzanne L Campion, Dmitriy M Chudakov, Persephone Borrow, Andrew J McMichael
Abstract
T follicular helper (Tfh) cells are fundamental for B cell selection and antibody maturation in germinal centers. Circulating Tfh (cTfh) cells constitute a minor proportion of the CD4+ T cells in peripheral blood, but their clonotypic relationship to Tfh populations resident in lymph nodes and the extent to which they differ from non-Tfh CD4+ cells have been unclear. Using donor-matched blood and tonsil samples, we investigate T cell receptor (TCR) sharing between tonsillar Tfh cells and peripheral Tfh and non-Tfh cell populations. TCR transcript sequencing reveals considerable clonal overlap between peripheral and tonsillar Tfh cell subsets as well as a clear distinction between Tfh and non-Tfh cells. Furthermore, influenza-specific cTfh cell clones derived from blood can be found in the repertoire of tonsillar Tfh cells. Therefore, human blood samples can be used to gain insight into the specificity of Tfh responses occurring in lymphoid tissues, provided that cTfh subsets are studied.
Keywords: T follicular helper cells; TCR repertoire; blood; influenza; tonsil.
Conflict of interest statement
DECLARATION OF INTERESTS
The authors declare no competing interests.
Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.
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References
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