Susceptibility of Tissue Cells to HIV

Mass cytometry, or CyTOF, is a powerful technology that has been used for comprehensive multiparameter characterization of immune cells. In collaboration with Dr. Marielle Cavrois (The J. David Gladstone Institutes), we recently conducted a 38-parameter characterization of HIV entry and productive infection of tissue CD4+ T cells by CyTOF, and used an analytical approach that takes advantage of the high-dimensional nature of CyTOF datasets to distinguish receptors modulated during infection from those differentially expressed on preferentially infected cells. These studies identified a subset of memory CD4+ T cells susceptible to HIV entry but not productive infection. Ongoing work in the lab seeks to characterize the molecular basis of this post-entry restriction, and to use CyTOF and a variety of high-dimensional CyTOF data analysis tools to characterize the types of cells that are productively and latently infected with HIV.



Schematic illustrating the steps involved in characterizing the susceptibility of tissue-derived CD4+ T cells to HIV infection. Tonsils were processed into human lymphocyte aggregate cultures (HLACs), infected with an HIV-1 reporter virus, and then monitored for HIV entry after 2 hours or productive infection after 4 days. Using a variety of visualization, clustering, and statistical approaches, the susceptibility of different subsets of CD4+ T cells to HIV entry and productive infection was assessed, which led to the discovery of a new subset of memory CD4+ T cells highly susceptible to HIV entry but not productive infection. We are currently using these analytical approaches to characterize how HIV changes the properties of CD4+ T cells upon infection, including studies using patient cells.