Longitudinal imaging of HIV-1 spread in humanized mice with parallel 3D immunofluorescence and electron tomography
Abstract
Dissemination of HIV-1 throughout lymphoid tissues leads to systemic virus spread following infection. We combined tissue clearing, 3D-immunofluorescence, and electron tomography (ET) to longitudinally assess early HIV-1 spread in lymphoid tissues in humanized mice. Immunofluorescence revealed peak infection density in gut at 10-12 days post-infection when blood viral loads were low. Human CD4+ T-cells and HIV-1-infected cells localized predominantly to crypts and the lower third of intestinal villi. Free virions and infected cells were not readily detectable by ET at 5-days post-infection, whereas HIV-1-infected cells surrounded by pools of free virions were present in ~10% of intestinal crypts by 10-12 days. ET of spleen revealed thousands of virions released by individual cells and discreet cytoplasmic densities near sites of prolific virus production. These studies highlight the importance of multiscale imaging of HIV-1-infected tissues and are adaptable to other animal models and human patient samples.
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Author details
Funding
National Institute of General Medical Sciences (2 P50 GM082545-06)
- Pamela J Bjorkman
California HIV/AIDS Research Program (ID15-CT-017)
- Pamela J Bjorkman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed according to the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#1702) of the California Institute of Technology. Full effort was made to minimize suffering during animal sacrifice.
Copyright
© 2017, Kieffer et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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