title: Conditioned medium from amniotic mesenchymal tissue cells reduces progression of bleomycin-induced lung fibrosis.
abstract: OBJECTIVE
  We have demonstrated recently that transplantation of placental membrane-derived cells reduces bleomycin-induced lung fibrosis in mice, despite a limited presence of transplanted cells in host lungs. Because placenta-derived cells are known to release factors with potential immunomodulatory and trophic activities, we hypothesized that transplanted cells may promote lung tissue repair via paracrine-acting molecules. To test this hypothesis, we examined whether administration of conditioned medium (CM) generated from human amniotic mesenchymal tissue cells (AMTC) was able to reduce lung fibrosis in this same animal model.
  
  
  METHODS
  Bleomycin-challenged mice were either treated with AMTC-CM or control medium, or were left untreated (Bleo group). After 9 and 14 days, the distribution and severity of lung fibrosis were assessed histologically with a scoring system. Collagen deposition was also evaluated by quantitative image analysis.
  
  
  RESULTS
  At day 14, lung fibrosis scores in AMTC-CM-treated mice were significantly lower (P < 0.05) compared with mice of the Bleo group, in terms of fibrosis distribution [1.0 (interquartile range, IQR 0.9) versus 3.0 (IQR 1.8)], fibroblast proliferation [0.8 (IQR 0.4) versus 1.6 (IQR 1.0)], collagen deposition [1.4 (IQR 0.5) versus 2.0 (IQR 1.2)] and alveolar obliteration [2.3 (IQR 0.8) versus 3.2 (IQR 0.5)]. No differences were observed between mice of the Bleo group and mice treated with control medium. Quantitative analysis of collagen deposition confirmed these findings. Importantly, AMTC-CM treatment significantly reduced the fibrosis progression between the two observation time-points.
  
  
  CONCLUSIONS
  This pilot study supports the notion that AMTC exert anti-fibrotic effects through release of yet unknown soluble factors.
authors.affiliation: Centro di Ricerca E. Menni, Fondazione Poliambulanza-Istituto Ospedaliero, Brescia, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Cargnoni
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Ressel
authors.forename: Daniele
authors.initials: D
authors.lastname: Rossi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Poli
authors.forename: Davide
authors.initials: D
authors.lastname: Arienti
authors.forename: Guerino
authors.initials: G
authors.lastname: Lombardi
authors.forename: Ornella
authors.initials: O
authors.lastname: Parolini
mesh_terms: D000653:Amniotic Fluid / Q000166:cytology* / Q000378:metabolism; D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000009:adverse effects*; D001761:Bleomycin / Q000009:adverse effects*; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism; D017077:Culture Media, Conditioned; D018450:Disease Progression; D005260:Female; D006801:Humans; D008648:Mesoderm / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D019899:Paracrine Communication; D010920:Placenta / Q000166:cytology* / Q000378:metabolism; D011247:Pregnancy; D011658:Pulmonary Fibrosis / Q000139:chemically induced* / Q000503:physiopathology; D046509:Tissue Culture Techniques
chemical_list: D000903:Antibiotics, Antineoplastic; D017077:Culture Media, Conditioned; D001761:Bleomycin; D003094:Collagen