title: Constitutive expression of the nef gene suppresses human immunodeficiency virus type 1 (HIV-1) replication in monocytic cell lines.
abstract: In order to study the effect of nef gene expression on viral replication in monocytic cells, we established monocytic (U937 and THP-1) cell transfectants constitutively expressing the human immunodeficiency virus type 1 nef gene. We constructed a plasmid expressing the nef gene derived from an infectious clone, NL432, under the control of SR alpha promoter which can drive a high level of gene expression. We found suppressed viral replication in nef-expressing monocytic cells, although a negative effect of nef was observed, with some variation depending on the virus strain and the cell. We also observed that the expression of the surface CD4 molecule is inversely related to the expression of the nef gene, especially in the U937 transfectants. These results indicate that the suppression of viral replication and the down-modulation of CD4 molecule by nef gene expression occur in monocytic cell lines as in T cell lines.
authors.affiliation: Department of Immunology, National Institute of Health, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tsunetsugu-Yokota
authors.forename: S
authors.initials: S
authors.lastname: Matsuda
authors.forename: M
authors.initials: M
authors.lastname: Maekawa
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: T
authors.initials: T
authors.lastname: Takemori
authors.forename: Y
authors.initials: Y
authors.lastname: Takebe
mesh_terms: D015704:CD4 Antigens / Q000096:biosynthesis; D002460:Cell Line; D015536:Down-Regulation; D015693:Gene Products, nef / Q000494:pharmacology*; D015754:Genes, nef / Q000235:genetics*; D014644:Genetic Variation; D015497:HIV-1 / Q000187:drug effects / Q000254:growth & development*; D009000:Monocytes / Q000382:microbiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D013997:Time Factors; D014162:Transfection; D014779:Virus Replication; D054311:nef Gene Products, Human Immunodeficiency Virus
chemical_list: D015704:CD4 Antigens; D015693:Gene Products, nef; D054311:nef Gene Products, Human Immunodeficiency Virus