Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.

Effective T cell responses can decisively influence the outcome of retroviral infection. However, what constitutes protective T cell responses or determines the ability of the host to mount such responses is incompletely understood. Here we studied the requirements for development and induction of C...

Full description

Saved in:
Bibliographic Details
Main Authors: George R Young, Mickaël J-Y Ploquin, Urszula Eksmond, Munisch Wadwa, Jonathan P Stoye, George Kassiotis
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2012-01-01
Series:PLoS Pathogens
Online Access:https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1002709&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850224658328059904
author George R Young
Mickaël J-Y Ploquin
Urszula Eksmond
Munisch Wadwa
Jonathan P Stoye
George Kassiotis
author_facet George R Young
Mickaël J-Y Ploquin
Urszula Eksmond
Munisch Wadwa
Jonathan P Stoye
George Kassiotis
author_sort George R Young
collection DOAJ
description Effective T cell responses can decisively influence the outcome of retroviral infection. However, what constitutes protective T cell responses or determines the ability of the host to mount such responses is incompletely understood. Here we studied the requirements for development and induction of CD4+ T cells that were essential for immunity to Friend virus (FV) infection of mice, according to their TCR avidity for an FV-derived epitope. We showed that a self peptide, encoded by an endogenous retrovirus, negatively selected a significant fraction of polyclonal FV-specific CD4+ T cells and diminished the response to FV infection. Surprisingly, however, CD4+ T cell-mediated antiviral activity was fully preserved. Detailed repertoire analysis revealed that clones with low avidity for FV-derived peptides were more cross-reactive with self peptides and were consequently preferentially deleted. Negative selection of low-avidity FV-reactive CD4+ T cells was responsible for the dominance of high-avidity clones in the response to FV infection, suggesting that protection against the primary infecting virus was mediated exclusively by high-avidity CD4+ T cells. Thus, although negative selection reduced the size and cross-reactivity of the available FV-reactive naïve CD4+ T cell repertoire, it increased the overall avidity of the repertoire that responded to infection. These findings demonstrate that self proteins expressed by replication-defective endogenous retroviruses can heavily influence the formation of the TCR repertoire reactive with exogenous retroviruses and determine the avidity of the response to retroviral infection. Given the overabundance of endogenous retroviruses in the human genome, these findings also suggest that endogenous retroviral proteins, presented by products of highly polymorphic HLA alleles, may shape the human TCR repertoire that reacts with exogenous retroviruses or other infecting pathogens, leading to interindividual heterogeneity.
format Article
id doaj-art-428fb6fa436c458cacbf3270d89fb342
institution OA Journals
issn 1553-7366
1553-7374
language English
publishDate 2012-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Pathogens
spelling doaj-art-428fb6fa436c458cacbf3270d89fb3422025-08-20T02:05:34ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742012-01-0185e100270910.1371/journal.ppat.1002709Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.George R YoungMickaël J-Y PloquinUrszula EksmondMunisch WadwaJonathan P StoyeGeorge KassiotisEffective T cell responses can decisively influence the outcome of retroviral infection. However, what constitutes protective T cell responses or determines the ability of the host to mount such responses is incompletely understood. Here we studied the requirements for development and induction of CD4+ T cells that were essential for immunity to Friend virus (FV) infection of mice, according to their TCR avidity for an FV-derived epitope. We showed that a self peptide, encoded by an endogenous retrovirus, negatively selected a significant fraction of polyclonal FV-specific CD4+ T cells and diminished the response to FV infection. Surprisingly, however, CD4+ T cell-mediated antiviral activity was fully preserved. Detailed repertoire analysis revealed that clones with low avidity for FV-derived peptides were more cross-reactive with self peptides and were consequently preferentially deleted. Negative selection of low-avidity FV-reactive CD4+ T cells was responsible for the dominance of high-avidity clones in the response to FV infection, suggesting that protection against the primary infecting virus was mediated exclusively by high-avidity CD4+ T cells. Thus, although negative selection reduced the size and cross-reactivity of the available FV-reactive naïve CD4+ T cell repertoire, it increased the overall avidity of the repertoire that responded to infection. These findings demonstrate that self proteins expressed by replication-defective endogenous retroviruses can heavily influence the formation of the TCR repertoire reactive with exogenous retroviruses and determine the avidity of the response to retroviral infection. Given the overabundance of endogenous retroviruses in the human genome, these findings also suggest that endogenous retroviral proteins, presented by products of highly polymorphic HLA alleles, may shape the human TCR repertoire that reacts with exogenous retroviruses or other infecting pathogens, leading to interindividual heterogeneity.https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1002709&type=printable
spellingShingle George R Young
Mickaël J-Y Ploquin
Urszula Eksmond
Munisch Wadwa
Jonathan P Stoye
George Kassiotis
Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.
PLoS Pathogens
title Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.
title_full Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.
title_fullStr Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.
title_full_unstemmed Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.
title_short Negative selection by an endogenous retrovirus promotes a higher-avidity CD4+ T cell response to retroviral infection.
title_sort negative selection by an endogenous retrovirus promotes a higher avidity cd4 t cell response to retroviral infection
url https://journals.plos.org/plospathogens/article/file?id=10.1371/journal.ppat.1002709&type=printable
work_keys_str_mv AT georgeryoung negativeselectionbyanendogenousretroviruspromotesahigheraviditycd4tcellresponsetoretroviralinfection
AT mickaeljyploquin negativeselectionbyanendogenousretroviruspromotesahigheraviditycd4tcellresponsetoretroviralinfection
AT urszulaeksmond negativeselectionbyanendogenousretroviruspromotesahigheraviditycd4tcellresponsetoretroviralinfection
AT munischwadwa negativeselectionbyanendogenousretroviruspromotesahigheraviditycd4tcellresponsetoretroviralinfection
AT jonathanpstoye negativeselectionbyanendogenousretroviruspromotesahigheraviditycd4tcellresponsetoretroviralinfection
AT georgekassiotis negativeselectionbyanendogenousretroviruspromotesahigheraviditycd4tcellresponsetoretroviralinfection