In JoVE (1)
Other Publications (1)
Articles by Zachary B. Davis in JoVE
Preparation and Use of HIV-1 Infected Primary CD4+ T-Cells as Target Cells in Natural Killer Cell Cytotoxic Assays Zachary B. Davis1, Jeffrey P. Ward1, Edward Barker1 1Department of Immunology and Microbiology, Rush University Medical Center Cytotoxicity assays to measure natural killer cell lytic responses to HIV-infected cells is limited by the purity of the target cells. We demonstrate here the isolation of a highly purified population of HIV-1 infected primary T-cell blasts by taking advantage of HIV-1 s ability to down-modulate CD4.
Other articles by Zachary B. Davis on PubMed
Degranulation of Natural Killer Cells Following Interaction with HIV-1-infected Cells is Hindered by Downmodulation of NTB-A by Vpu Cell Host & Microbe. Nov, 2010 | Pubmed ID: 21075351 Natural killer (NK) cell degranulation in response to virus-infected cells is triggered by interactions between invariant NK cell surface receptors and their ligands on target cells. Although HIV-1 Vpr induces expression of ligands for NK cell activation receptor, NKG2D, on infected cells, this is not sufficient to promote lytic granule release. We show that triggering the NK cell coactivation receptor NK-T- and -B cell antigen (NTB-A) alongside NKG2D promotes NK cell degranulation. Normally, NK cell surface NTB-A binds to NTB-A on CD4+ T cells. However, HIV-1 Vpu downmodulates NTB-A on infected T cells. Vpu associates with NTB-A through its transmembrane region without promoting NTB-A degradation. Cells infected with HIV-1 Vpu mutant elicited at least 50% more NK cells to degranulate than wild-type virus. Moreover, NK cells have a higher capacity to lyse HIV-infected cells with a mutant Vpu. Thus, Vpu downmodulation of NTB-A protects the infected cell from lysis by NK cells.