HIV/AIDS remains a global public health problem with over 33 million people infected worldwide. High-resolution imaging of infected tissues by three-dimensional electron microscopy can reveal details of the structure of HIV-1, how it infects cells, and how and where the virus accumulates within different tissue sub-structures.
Three-dimensional electron microscopy had previously only been performed to image infected cultured cells or purified virus. This paper uses electron tomography (ET) to examine an active infection in the gastrointestinal tract of HIV-1–infected mice with humanized immune systems, allowing visualization of the interplay between the virus and host immune cells. Not only does it reveal details on how the virus quickly infects immune cells in the gut, using them as virus-producing factories, but it also highlights where the virus “hides out” deep within the intestinal tissue.
Three-dimensional imaging of an HIV-1 infection in tissue uncovers differences between cultured cell and tissue models of HIV-1 infection and in vivo infections and furthers our understanding of HIV-1/AIDS as a disease of mucosal tissues.