Use of a three-dimensional cell culture model to study airway smooth muscle-mast cell interactions in airway remodeling.
Increased airway smooth muscle (ASM) mass and infiltration by mast cells are key features of airway remodeling in asthma. We describe a model to investigate the relationship between ASM, the extracellular matrix, mast cells, and airway remodeling. ASM cells were cultured in a three-dimensional (3-D) collagen I gel (3-D culture) alone or with mast cells. Immunocytochemistry and Western blotting of ASM in 3-D cultures revealed a spindle-shaped morphology and significantly lower alpha-smooth muscle actin and vimentin expression than in ASM cultured in monolayers on collagen type I or plastic (2-D culture). In 3-D cultures, basal ASM proliferation, examined by Ki67 immunocytochemistry, was reduced to 33 +/- 7% (P < 0.05) of that in 2-D cultures. The presence of mast cells in cocultures increased ASM proliferation by 1.8-fold (P < 0.05). Gelatin zymography revealed more active matrix metalloproteinase (MMP)-2 in 3-D than in 2-D culture supernatants over 7 days. Functional MMP activity was examined by gel contraction. The spontaneous gel contraction over 7 days was significantly inhibited by the MMP inhibitor ilomastat. Mast cell coculture enhanced ASM gel contraction by 22 +/- 16% (not significant). Our model shows that ASM has different morphology, with lower contractile protein expression and basal proliferation in 3-D culture. Compared with standard techniques, ASM synthetic function, as shown by MMP production and activity, is sustained over longer periods. The presence of mast cells in the 3-D model enhanced ASM proliferation and MMP production. Airway remodeling in asthma may be more accurately modeled by our system than by standard culture systems.
Divisions of Therapeutics and Molecular Medicine, University of Nottingham, Nottingham, United Kingdom.
Claudia C
CC
Ceresa
Alan J
AJ
Knox
Simon R
SR
Johnson
D001249:Asthma / Q000473:pathology / Q000503:physiopathology; D001980:Bronchi / Q000166:cytology* / Q000502:physiology; D002450:Cell Communication / Q000502:physiology*; D002455:Cell Division / Q000502:physiology; D048430:Cell Shape / Q000502:physiology; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D005109:Extracellular Matrix / Q000378:metabolism; D006801:Humans; D008407:Mast Cells / Q000166:cytology*; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D009130:Muscle, Smooth / Q000166:cytology* / Q000502:physiology; D011014:Pneumonia / Q000473:pathology* / Q000503:physiopathology
D020778:Matrix Metalloproteinase 2