title: Macrophage-derived Hedgehog ligands promotes fibrogenic and angiogenic responses in human schistosomiasis mansoni.
abstract: BACKGROUND
  Schistosomiasis mansoni is a major cause of portal fibrosis and portal hypertension. The Hedgehog pathway regulates fibrogenic repair in some types of liver injury.
  
  
  OBJECTIVE
  Determine if Hedgehog pathway activation occurs during fibrosis progression in schistosomiasis and to determine if macrophage-related mechanisms are involved.
  
  
  METHODS
  Immunohistochemistry was used to characterize the cells that generate and respond to Hedgehog ligands in 28 liver biopsies from patients with different grades of schistosomiasis fibrosis staged by ultrasound. Cultured macrophages (RAW264.7 and primary rat Kupffer cells) and primary rat liver sinusoidal endothelial cells (LSEC) were treated with schistosome egg antigen (SEA) and evaluated using qRT-PCR. Inhibition of the Hedgehog pathway was used to investigate its role in alternative activation of macrophages (M2) and vascular tube formation.
  
  
  RESULTS
  Patients with schistosomiasis expressed more ligands (Shh and Ihh) and target genes (Patched and Gli2) than healthy individuals. Activated LSEC and myofibroblasts were Hedgehog responsive [Gli2(+)] and accumulated in parallel with fibrosis stage (P < 0.05). Double IHC for Ihh/CD68 showed that Ihh(+) cells were macrophages. In vitro studies demonstrated that SEA-stimulated macrophages to express Ihh and Shh mRNA (P < 0.05). Conditioned media from such macrophages induced luciferase production by Shh-LightII cells (P < 0.001) and Hedgehog inhibitors blocked this effect (P < 0.001). SEA-treated macrophages also up-regulated their own expression of M2 markers, and Hh pathway inhibitors abrogated this response (P < 0.01). Inhibition of the Hedgehog pathway in LSEC blocked SEA-induced migration and tube formation.
  
  
  CONCLUSIONS
  SEA stimulates liver macrophages to produce Hh ligands, which promote alternative activation of macrophages, fibrogenesis and vascular remodelling in schistosomiasis.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Duke University Medical Center, Durham, NC, USA.
authors.forename: Thiago A
authors.initials: TA
authors.lastname: Pereira
authors.forename: Guanhua
authors.initials: G
authors.lastname: Xie
authors.forename: Steve S
authors.initials: SS
authors.lastname: Choi
authors.forename: Wing-Kin
authors.initials: WK
authors.lastname: Syn
authors.forename: Izabela
authors.initials: I
authors.lastname: Voieta
authors.forename: Jiuyi
authors.initials: J
authors.lastname: Lu
authors.forename: Isaac S
authors.initials: IS
authors.lastname: Chan
authors.forename: Marzena
authors.initials: M
authors.lastname: Swiderska
authors.forename: Kirsten B
authors.initials: KB
authors.lastname: Amaral
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Antunes
authors.forename: William E
authors.initials: WE
authors.lastname: Secor
authors.forename: Rafal P
authors.initials: RP
authors.lastname: Witek
authors.forename: José R
authors.initials: JR
authors.lastname: Lambertucci
authors.forename: Fausto L
authors.initials: FL
authors.lastname: Pereira
authors.forename: Anna Mae
authors.initials: AM
authors.lastname: Diehl
mesh_terms: D000328:Adult; D000818:Animals; D001706:Biopsy; D002460:Cell Line; D042783:Endothelial Cells / Q000378:metabolism / Q000469:parasitology; D005260:Female; D017930:Genes, Reporter; D053823:Hedgehog Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007728:Kupffer Cells / Q000378:metabolism; D008024:Ligands; D008099:Liver / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000469:parasitology / Q000473:pathology; D008103:Liver Cirrhosis / Q000175:diagnosis / Q000378:metabolism* / Q000469:parasitology / Q000503:physiopathology; D008262:Macrophage Activation; D008264:Macrophages / Q000378:metabolism* / Q000469:parasitology / Q000473:pathology; D008297:Male; D051379:Mice; D008875:Middle Aged; D058628:Myofibroblasts / Q000378:metabolism / Q000469:parasitology; D009389:Neovascularization, Pathologic; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D012550:Schistosoma mansoni / Q000378:metabolism; D012555:Schistosomiasis mansoni / Q000150:complications* / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology; D012720:Severity of Illness Index; D015398:Signal Transduction; D014162:Transfection; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D053823:Hedgehog Proteins; C509246:IHH protein, human; C550919:Ihh protein, rat; D008024:Ligands; C509239:SHH protein, human; C546888:Shh protein, rat; C514061:ihh protein, mouse