Up-regulation of iNOS mRNA expression and increased production of NO in human monoblast cell line, U937 transfected by HTLV-I tax gene.
We investigated the mRNA expression of inducible nitric oxide synthase (iNOS) and the production of nitric oxide (NO) in human T cell lymphotropic virus type I (HTLV-I) p40tax-transfected U937 cells, a human monoblast cell line. Transfection of HTLV-I p40tax U937 cells induced up-regulation of iNOS mRNA expression and subsequent NO production. Furthermore, interferon gamma (IFN-gamma) stimulation of HTLV-I p40tax-transfected U937 cells enhanced iNOS mRNA expression and NO production. The kinetics of iNOS mRNA expression and NO production indicated maximal effect at 24 and 48 hours, respectively, after culture with or without IFN-gamma. These findings suggest that HTLV-I p40tax can act as a transactivator of NO production in cells of Mo/M phi lineage. To what extent this mechanism may be involved in the pathogenesis of HTLV-I-associated diseases warrants further investigation.
Goto
H
H
First Department of Internal Medicine, Nagasaki University School of Medicine, Japan.
Nakamura
T
T
Shirabe
S
S
Ueki
Y
Y
Nishiura
Y
Y
Furuya
T
T
Tsujino
A
A
Nakane
S
S
Eguchi
K
K
Nagataki
S
S
D004790:Enzyme Induction; D015973:Gene Expression Regulation, Leukemic; D015967:Gene Expression Regulation, Viral; D016356:Gene Products, tax / Q000502:physiology*; D016355:Genes, pX; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology; D009000:Monocytes / Q000201:enzymology*; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis* / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000502:physiology; D015533:Transcriptional Activation; D014162:Transfection; D014407:Tumor Cells, Cultured
D016356:Gene Products, tax; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D009569:Nitric Oxide; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II