Longitudinal bioluminescent imaging of HIV-1 infection during antiretroviral therapy and treatment interruption in humanized mice.

John D Ventura,Tongyu Zhang,Pradeep D Uchil,Collin Kieffer,Jagadish Beloor,Priti Kumar,Walther Mothes,Christina Ochsenbauer,Kelsey A Haugh,Thomas J Hope,Edward Allen,Stuart J.D Neil

doi:10.1371/journal.ppat.1008161

Abstract

Non-invasive bioluminescent imaging (NIBLI) of HIV-1 infection dynamics allows for real-time monitoring of viral spread and the localization of infected cell populations in living animals. In this report, we describe full-length replication-competent GFP and Nanoluciferase (Nluc) expressing HIV-1 reporter viruses from two clinical transmitted / founder (T/F) strains: TRJO.c and Q23.BG505. By infecting humanized mice with these HIV-1 T/F reporter viruses, we were able to directly monitor longitudinal viral spread at whole-animal resolution via NIBLI at a sensitivity of as few as 30–50 infected cells. Bioluminescent signal strongly correlated with HIV-1 infection and responded proportionally to virus suppression in vivo in animals treated daily with a combination antiretroviral therapy (cART) regimen. Longitudinal NIBLI following cART withdrawal visualized tissue-sites that harbored virus during infection recrudescence. Notably, we observed rebounding infection in the same lymphoid tissues where infection was first observed prior to ART treatment. Our work demonstrates the utility of our system for studying in vivo viral infection dynamics and identifying infected tissue regions for subsequent analyses.

Highlights

Whole-body non-invasive bioluminescent imaging (NIBLI) of bacterial and viral pathogens in small animal models is a powerful and versatile experimental tool
We have taken advantage of the small luciferase reporter protein, Nanoluciferase (Nluc), to generate a replication-competent HIV-1 reporter virus to allow for Non-invasive bioluminescent imaging (NIBLI) of viral infection in humanized mice
R01AI112443, awarded to PK Confocal microscopy was conducted at the Yale Confocal Microscopy Facility at the Yale Center for Cellular and Molecular Imaging, funded in part by the NIH, grant S10OD020142

Summary

Introduction

Whole-body non-invasive bioluminescent imaging (NIBLI) of bacterial and viral pathogens in small animal models is a powerful and versatile experimental tool. NIBLI enables longitudinal real-time monitoring of infection over time in the same animal by exploiting the high sensitivity and dynamic range offered by bioluminescent reporter genes such as luciferases. There is great interest in extending non-invasive imaging technology to longitudinally image HIV-1 and SIV infection in vivo. Positron Emission Tomography (PET) using Copper (64Cu)-labeled α-SIV Gp120 immune-labeling of SIVmac239 (i.e. immuno-PET) allows non-invasive real-time monitoring of infected non-human primates (NHPs) by detecting virus compartmentalization in living animals [13]. Given the high costs of immuno-PET imaging in NHPs, non-PET based NIBLI systems for small animal models would be more widely accessible and complement the immune-PET imaging in NHP. The development of NIBLI for HIV-1 in humanized mice would be an asset for investigators interested in viral transmission, pathogenesis, and whole-animal spread

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