title: A novel real-time CTL assay to measure designer T-cell function against HIV Env(+) cells.
abstract: BACKGROUND
  To increase the immunosurveillance in HIV infection, we used retroviral vectors expressing CD4-chimeric antigen receptors (CARs) to genetically modify autologous T cells and redirect CTL toward HIV. The CD4 extracellular domain targets envelope and the intracellular signaling domains activate T cells. The maC46 fusion inhibitor binds HIV and blocks viral replication.
  
  
  METHODS
  We stimulated rhesus PBMCs with antibodies to CD3/CD28 and cotransduced T cells with CD4-CAR and maC46 vectors. CD4-CAR-transduced T cells were added to Env(+) 293T cells at E:T of 1:1. Killing of target cells was measured as reduced impedance.
  
  
  RESULTS
  We observed gene expression in 60-70% of rhesus CD3(+) CD8(+) T cells with the individual vectors and in 35% of the cells with both vectors. CD4-CAR-transduced populations specifically killed Env(+) cells.
  
  
  CONCLUSIONS
  In these studies, we showed that designer T cells were redirected to kill Env(+) cells. Control of viremia without HAART would revolutionize treatment for HIV patients.
authors.affiliation: Tulane National Primate Research Center, Covington, LA, USA.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: MacLean
authors.forename: Edith
authors.initials: E
authors.lastname: Walker
authors.forename: Gautam K
authors.initials: GK
authors.lastname: Sahu
authors.forename: Gail
authors.initials: G
authors.lastname: Skowron
authors.forename: Preston
authors.initials: P
authors.lastname: Marx
authors.forename: Dorothee
authors.initials: D
authors.lastname: von Laer
authors.forename: Richard P
authors.initials: RP
authors.lastname: Junghans
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Braun
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004553:Electric Conductivity; D017097:Electric Impedance; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007167:Immunotherapy; D008253:Macaca mulatta; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014779:Virus Replication; D054299:env Gene Products, Human Immunodeficiency Virus / Q000235:genetics* / Q000378:metabolism
chemical_list: D054299:env Gene Products, Human Immunodeficiency Virus
keywords: CD4-CAR; cytotoxic T lymphocytes; dTc; maC46; rhesus macaque; transduced T cells