title: Characterization of monocyte differentiation-inducing (MDI) factors derived from human fetal membrane chorion cells undergoing apoptosis after influenza virus infection.
abstract: Influenza virus infection during pregnancy has been implicated as one of cause of premature delivery, abortion and stillbirth. We have reported that cultured human fetal membrane chorion cells undergoing apoptosis by influenza virus infection secrete unidentified heat-stable monocyte differentiation-inducing (MDI) factors. In this study, cellular, biological and immunochemical characteristics of MDI factors were investigated using human monocytic leukemia THP-1 cells by nitroblue tetrazolium reduction and cell adhesion assays. The treatment of THP-1 cells with culture supernatants from the influenza virus-infected chorion cells induced the nitroblue tetrazolium reduction ability, which was inhibited by the addition of superoxide dismutase and diphenyleneiodonium chloride, an inhibitor for reduced nicotinamide adenine dinucleotide phosphate oxidase. The phenomenon was also observed in human peripheral blood monocytes and histiocytic leukemia U937 cells, but not in promyelocytic leukemia HL-60 cells. The induction of nitroblue tetrazolium reduction and adhesion abilities in THP-1 cells was closely correlated with the concentrations of interleukin-6 protein in the culture supernatants. These abilities were inhibited to approximately 60% by the addition of antibodies against interleukin-6, or alpha-chain (gp80) or beta-chain (gp130) of IL-6 receptor. The induction of nitroblue tetrazolium reduction was increased by the addition of supernatants from amniochorion tissue cultures after influenza virus infection. These results indicate that chorion cell-derived interleukin-6 is partly responsible for monocyte differentiation to macrophages capable of generating superoxide anion. It is possible that these pathways represent part of the mechanism for birth complications associated with intrauterine influenza infection in pregnancy.
authors.affiliation: Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. uchide@ps.toyaku.ac.jp
authors.forename: Noboru
authors.initials: N
authors.lastname: Uchide
authors.forename: Chiho
authors.initials: C
authors.lastname: Tadera
authors.forename: Hiroko
authors.initials: H
authors.lastname: Sarai
authors.forename: Kunio
authors.initials: K
authors.lastname: Ohyama
authors.forename: Toshio
authors.initials: T
authors.lastname: Bessho
authors.forename: Hiroo
authors.initials: H
authors.lastname: Toyoda
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D002823:Chorion / Q000166:cytology / Q000378:metabolism* / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay; D005321:Extraembryonic Membranes / Q000166:cytology / Q000378:metabolism / Q000821:virology; D005260:Female; D018922:HL-60 Cells; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000378:metabolism / Q000502:physiology; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000166:cytology / Q000378:metabolism*; D009975:Orthomyxoviridae / Q000254:growth & development*; D020298:U937 Cells
chemical_list: D015850:Interleukin-6