title: The non-immunosuppressive cyclosporin A analogue SDZ NIM 811 inhibits cyclophilin A incorporation into virions and virus replication in human immunodeficiency virus type 1-infected primary and growth-arrested T cells.
abstract: SDZ NIM 811 is a cyclosporin A (CsA) analogue that is completely devoid of immunosuppressive capacity but exhibits potent and selective anti-human immunodeficiency virus type 1 (HIV-1) activity. Binding to cyclophilin A, the intracellular receptor for cyclosporins, is a prerequisite for HIV-1 inhibition by cyclosporins. Cyclophilin A was demonstrated to bind to HIV-1 p24gag and this cyclophilin-Gag interaction leads to the incorporation of cyclophilin A into HIV-1 virions. SDZ NIM 811 inhibits this protein interaction, and this is likely to be the molecular basis for its antiviral activity. Here, we show that in activated primary T cells SDZ NIM 811 interferes with two stages of the virus replication cycle: (i) translocation of pre-integration complexes into the nucleus and (ii) production of infectious virus particles. SDZ NIM 811 not only inhibits translocation of HIV-1 pre-integration complexes in primary T cells, but also in a growth-arrested T cell line. In vivo, most T lymphocytes are quiescent, but serve nevertheless as a major and inducible HIV-1 reservoir in infected individuals. Significant amounts of cyclophilin A were found to be associated with virus particles propagated in primary T cells. SDZ NIM 811 caused a strong reduction in the amount of incorporated cyclophilin A, thereby reducing infectivity. Thus, cyclophilin A seems to be necessary for HIV-1 replication in primary T cells.
authors.affiliation: Sandoz Research Institute, Vienna, Austria.
authors.forename: E
authors.initials: E
authors.lastname: Mlynar
authors.forename: D
authors.initials: D
authors.lastname: Bevec
authors.forename: A
authors.initials: A
authors.lastname: Billich
authors.forename: B
authors.initials: B
authors.lastname: Rosenwirth
authors.forename: A
authors.initials: A
authors.lastname: Steinkasserer
mesh_terms: D019380:Anti-HIV Agents / Q000494:pharmacology*; D002455:Cell Division; D016572:Cyclosporine / Q000378:metabolism / Q000494:pharmacology*; D004347:Drug Interactions; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D013601:T-Lymphocytes / Q000473:pathology / Q000821:virology*; D014771:Virion / Q000187:drug effects; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D019380:Anti-HIV Agents; D016572:Cyclosporine; C090438:(melle-4)cyclosporin