title: T-cell protection and enrichment through lentiviral CCR5 intrabody gene delivery.
abstract: CCR5 is the chemokine co-receptor for R5-tropic human immunodeficiency virus type 1 (HIV-1) isolates most often associated with primary infection. We have developed an HIV-1 self-inactivating vector, CAD-R5, containing a CCR5 single-chain antibody (intrabody) gene, which when expressed in T-cell lines and primary CD4+ T cells disrupts CCR5 cell surface expression and provides protection from R5-tropic isolate exposure. Furthermore, CAD-R5 intrabody expression in primary CD4+ T cells supports significant growth and enrichment over time during HIV-1-pulsed dendritic cell-T-cell interactions. These results indicate that CCR5 intrabody-expressing CD4+ T cells are refractory against this highly efficient primary route of infection. CD34+ cells transduced with the CAD-R5 vector gave rise to CD4+ and CD8+ thymocytes in non-obese diabetic (NOD)/ severely combined-immunodeficient (SCID)-human thymus/liver (hu thy/liv) mice, suggesting that CCR5 intrabody expression can be maintained throughout differentiation without obvious cellular effects. CD4+ T cells isolated from NOD/SCID-hu thy/liv mice were resistant to R5-tropic HIV-1 challenge demonstrating the maintenance of protection. Our findings demonstrate delivery of anti-HIV-1 activity through CCR5 intrabodies in primary CD4+ T cells and CD34+ cell-derived T-cell progeny. Thus, gene delivery strategies that provide a selective survival and growth advantage for T effector cells may provide a therapeutic benefit for HIV-1-infected individuals who have failed conventional therapies.
authors.affiliation: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: C H
authors.initials: CH
authors.lastname: Swan
authors.forename: B
authors.initials: B
authors.lastname: Bühler
authors.forename: P
authors.initials: P
authors.lastname: Steinberger
authors.forename: M P
authors.initials: MP
authors.lastname: Tschan
authors.forename: C F
authors.initials: CF
authors.lastname: Barbas
authors.forename: B E
authors.initials: BE
authors.lastname: Torbett
mesh_terms: D000818:Animals; D000906:Antibodies / Q000235:genetics* / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000821:virology; D002460:Cell Line; D002478:Cells, Cultured; D019610:Cytoprotection; D003713:Dendritic Cells / Q000276:immunology / Q000821:virology; D005786:Gene Expression Regulation; D015316:Genetic Therapy / Q000379:methods*; D015658:HIV Infections / Q000276:immunology / Q000628:therapy*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D019713:Receptors, CCR5 / Q000235:genetics* / Q000378:metabolism
chemical_list: D000906:Antibodies; D019713:Receptors, CCR5