Next Article in Journal
Species C Rotaviruses in Children with Diarrhea in India, 2010–2013: A Potentially Neglected Cause of Acute Gastroenteritis
Next Article in Special Issue
Vertical Transmission of Listeria monocytogenes: Probing the Balance between Protection from Pathogens and Fetal Tolerance
Previous Article in Journal
Microbiological Values of Rainwater Harvested in Adelaide
Previous Article in Special Issue
The Listeria monocytogenes Key Virulence Determinants hly and prfA are involved in Biofilm Formation and Aggregation but not Colonization of Fresh Produce
Article Menu

Export Article

Open AccessArticle
Pathogens 2018, 7(1), 22; https://doi.org/10.3390/pathogens7010022

IFN-Gamma-Dependent and Independent Mechanisms of CD4+ Memory T Cell-Mediated Protection from Listeria Infection

Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
*
Author to whom correspondence should be addressed.
Received: 3 January 2018 / Revised: 29 January 2018 / Accepted: 11 February 2018 / Published: 13 February 2018
(This article belongs to the Special Issue Listeria monocytogenes and Its Interactions with the Host)
View Full-Text   |   Download PDF [2657 KB, uploaded 13 February 2018]   |  

Abstract

While CD8+ memory T cells can promote long-lived protection from secondary exposure to intracellular pathogens, less is known regarding the direct protective mechanisms of CD4+ T cells. We utilized a prime/boost model in which mice are initially exposed to an acutely infecting strain of lymphocytic choriomeningitis virus (LCMV), followed by a heterologous rechallenge with Listeria monocytogenes recombinantly expressing the MHC Class II-restricted LCMV epitope, GP61–80 (Lm-gp61). We found that heterologous Lm-gp61 rechallenge resulted in robust activation of CD4+ memory T cells and that they were required for rapid bacterial clearance. We further assessed the relative roles of TNF and IFNγ in the direct anti-bacterial function of CD4+ memory T cells. We found that disruption of TNF resulted in a complete loss of protection mediated by CD4+ memory T cells, whereas disruption of IFNγ signaling to macrophages results in only a partial loss of protection. The protective effect mediated by CD4+ T cells corresponded to the rapid accumulation of pro-inflammatory macrophages in the spleen and an altered inflammatory environment in vivo. Overall, we conclude that protection mediated by CD4+ memory T cells from heterologous Listeria challenge is most directly dependent on TNF, whereas IFNγ only plays a minor role. View Full-Text
Keywords: immunological memory; secondary challenge; CD4+ T cells; Listeria monocytogenes immunological memory; secondary challenge; CD4+ T cells; Listeria monocytogenes
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Meek, S.M.; Williams, M.A. IFN-Gamma-Dependent and Independent Mechanisms of CD4+ Memory T Cell-Mediated Protection from Listeria Infection. Pathogens 2018, 7, 22.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Pathogens EISSN 2076-0817 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top