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Journal articles
Plasmacytoid dendritic cells engagement by influenza vaccine as a surrogate strategy for driving T-helper type 1 responses in human neonatal settings.
Abstract : The elicitation of T-helper type 1 (Th1) cellular immunity to eradicate intracellular pathogens is a challenging task because of the interleukin 12 (IL-12) deficit observed in early infancy. Screening cord blood responses to various pediatric vaccines and Toll-like receptor (TLR) agonists for innate responses and CD4(+) T-cell differentiation. We identified that nonadjuvanted inactivated trivalent influenza vaccine (TIV) was able to cosignal T cells for the production of interferon γ (IFN-γ) in a neonatal setting. This process includes the mobilization of neonatal plasmacytoid dendritic cells (pDCs) as antigen-presenting cells (APCs) that efficiently engage Th1 cells in an IL-12-independent but type I IFN-dependent manner. In addition, cord blood pDCs efficiently cross-presented antigen to CD8(+) T cells. Importantly, activation by TIV mainly requires TLR7; however, R848/TLR7- and CpGB/TLR9-activated pDCs, which poorly produced IFN-α, induce neonatal Th2 responses. TLR pathway engagement in pDCs is necessary but not sufficient for a successful neonatal Th1 outcome. We provide evidence of a mature and functional neonatal immune system at the level of APCs and T cells and propose to implement the IFN-α/IFN-γ axis in pediatric vaccination as a surrogate for the defective IL-12/IFN-γ axis.
https://hal-pasteur.archives-ouvertes.fr/pasteur-01108113
Contributor : Isma Ziani <>
Submitted on : Thursday, January 22, 2015 - 11:11:05 AM
Last modification on : Monday, June 14, 2021 - 5:14:02 PM
Contributor : Isma Ziani <>
Submitted on : Thursday, January 22, 2015 - 11:11:05 AM
Last modification on : Monday, June 14, 2021 - 5:14:02 PM