Gag-positive reservoir cells can be identified by a new technique and can be cleared by CTL ?
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Gag-positive reservoir cells can be identified by a new technique and can be cleared by CTL ? Una O’Doherty June 29, 2013
description
Gag-positive reservoir cells can be identified by a new technique and can be cleared by CTL ?. Una O’ Doherty June 29, 2013. Our experimental system. HLADR-, CD69-, CD25- CD4+ T Or CD3C28 activated. Infect (X4 or R5 HIV). Culture 3-4d. Measure total & integrated HIV DNA. - PowerPoint PPT Presentation
Transcript of Gag-positive reservoir cells can be identified by a new technique and can be cleared by CTL ?
Gag-positive reservoir cells can be identified by a new technique and can be cleared by CTL ?
Una O’DohertyJune 29, 2013
Infect (X4 or R5 HIV)
Culture 3-4d
Measure total & integrated HIV DNA
Our experimental system
O’Doherty U J. Virol. 2000O’Doherty U J.Virol. 2002Swiggard WJ J. Virol. 2005
Measure Gag expression
HLADR-, CD69-, CD25- CD4+ TOrCD3C28 activated
Gag expression in resting cells without spreading expression
Resting cells produce Gag
Pace PLoS Pathogen 2012
Activated
but little EnvMay explain lack of spreading infection
Activations with CD3/28 increase both Gag & Env
Can Gag expression lead to clearance of latently infected cells?
in vitro model for reservoir clearance
CD4+T
CD8+T
+ HIV
HIV
+/-Integrase inhibitor
granules
Migueles Immunity 2008
Gag expression leads to clearance of latently infected cells
Do Gag expressing resting CD4+T cell exist in vivo?
Gag expressing resting T exist in vivo
Calculation of the fraction of integrated HIV DNA expressing Gag
Calculation assumes all integrated HIV DNA is in resting CD4+ T cells so % expressing Gag is likely an underestimate
Is there any evidence for CTL clearance of reservoir in vivo?
CTL activity against latent cells correlates with reservoir size in vivo
In v
ivo
In vitro
p < 0.05 for blue (CP) and red (EC)
Integration correlates with IUPM
Menodoza Blood 2012Eriksson PLoS Pathogen 2013
Summary of in vitro and in vivo findings
Latently infected cells can express HIV proteins – continuum of latency
CTL clear latently infected cells
A fraction of the reservoir in rCD4T express Gag in vivo in patients on ART
CTL activity against latently infected CD4+ T cells may be a determinant of integration levels
Implications for functional cure
CTL may have activity against GPR - suggests expanded targets of CTL against latent cells and potential for therapeutic vaccines
Integrated HIV DNA measurements are useful to evaluate therapies that target HIV reservoirs
Superinfected resting CD4+ T cells provide a model of latency and immune clearance
Acknowledgements
Erin GrafMatt PaceLuis Agosto Jenny YuLindsay LynchLaura DeMaster
NIH:Michele Di MascioStephen MiguelesMark Connors
UCSF:Steve DeeksHiroyu HatanoRick Hecht
Penn:Jim RileyCarl JuneDon SiegelDrew WeissmanMike Betts
Penn CFAR:Farida Shaheen
Funding:NIH, Merck, amfAR, PKC
pharmaceuticals
Sorting for Gag + resting T in vivo
(except CD4)
PBMCs from ART suppressed patients and stained with anti-Gag
Gag expressing resting T exist in vivo
Gag expressing resting T in vivo
