Ion-Abrasion Scanning Electron Microscopy Reveals Surface-Connected Tubular Conduits in HIV-Infected Macrophages

PLoS Pathogens

Haifeng He¹  Eric O. Freed²  Karine Gousset²  Sriram Subramaniam³  Adam E. Bennett³  Kedar Narayan³  Lisa M. Hartnell³  Dan Shi³  Donald Bliss⁴  Bradley C. Lowekamp⁴  Terry S. Yoo⁴ 

[1] FEI Company, Hillsboro, Oregon, United States of America;HIV Drug Resistance Program, NCI, Frederick, Maryland, United States of America;Laboratory of Cell Biology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America;National Library of Medicine, NIH, Bethesda, Maryland, United States of America

关键词: Virions;    Macrophages;    HIV-1;    Cell membranes;    T cells;    Scanning electron microscopy;    Transmission electron microscopy;    Tomography;   

DOI  :  10.1371/journal.ppat.1000591

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

HIV-1-containing internal compartments are readily detected in images of thin sections from infected cells using conventional transmission electron microscopy, but the origin, connectivity, and 3D distribution of these compartments has remained controversial. Here, we report the 3D distribution of viruses in HIV-1-infected primary human macrophages using cryo-electron tomography and ion-abrasion scanning electron microscopy (IA-SEM), a recently developed approach for nanoscale 3D imaging of whole cells. Using IA-SEM, we show the presence of an extensive network of HIV-1-containing tubular compartments in infected macrophages, with diameters of ∼150–200 nm, and lengths of up to ∼5 µm that extend to the cell surface from vesicular compartments that contain assembling HIV-1 virions. These types of surface-connected tubular compartments are not observed in T cells infected with the 29/31 KE Gag-matrix mutant where the virus is targeted to multi-vesicular bodies and released into the extracellular medium. IA-SEM imaging also allows visualization of large sheet-like structures that extend outward from the surfaces of macrophages, which may bend and fold back to allow continual creation of viral compartments and virion-lined channels. This potential mechanism for efficient virus trafficking between the cell surface and interior may represent a subversion of pre-existing vesicular machinery for antigen capture, processing, sequestration, and presentation.

【 授权许可】

CC BY