Abstract
Myofibroblasts, defined by their expression of smooth muscle alpha-actin, appear at corneal and dermal incisions and promote wound contraction. We report here that cultured fibroblasts differentiate into myofibroblasts by a cell density-dependent mechanism. Fibroblasts seeded at low density (5 cells per mm2) produced a cell culture population consisting of 70-80% myofibroblasts, 5-7 days after seeding. In contrast, fibroblasts seeded at high density (500 cells per mm2) produced cultures with only 5-10% myofibroblasts. When the myofibroblast-enriched cultures were subsequently passaged at high density, the smooth muscle alpha-actin phenotype was lost within 3 days. Furthermore, initially 60% of the low density-cultured cells incorporated BrdUrd compared to 30% of cells passaged at high density. Media from myofibroblast-enriched cultures had more latent and active transforming growth factor beta (TGF-beta) than did media from fibroblast-enriched cultures. Although there was a trend towards increased numbers of myofibroblasts after addition of exogenous TGF-beta, the results did not reach statistical significance. We conclude that myofibroblast differentiation can be induced in fibroblasts by plating at low density. We propose a cell density-dependent model of myofibroblast differentiation during wounding and healing in which at least two factors interact: loss of cell contact and the presence of TGF-beta.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Abe M., Harpel J. G., Metz C. N., Nunes I., Loskutoff D. J., Rifkin D. B. An assay for transforming growth factor-beta using cells transfected with a plasminogen activator inhibitor-1 promoter-luciferase construct. Anal Biochem. 1994 Feb 1;216(2):276–284. doi: 10.1006/abio.1994.1042. [DOI] [PubMed] [Google Scholar]
- Applegate D., Feng W., Green R. S., Taubman M. B. Cloning and expression of a novel acidic calponin isoform from rat aortic vascular smooth muscle. J Biol Chem. 1994 Apr 8;269(14):10683–10690. [PubMed] [Google Scholar]
- Awata T., Nishida T., Nakagawa S., Manabe R. Differential regulation of fibronectin synthesis in three different types of corneal cells. Jpn J Ophthalmol. 1989;33(1):132–143. [PubMed] [Google Scholar]
- Berman M. B. Regulation of corneal fibroblast MMP-1 collagenase secretion by plasmin. Cornea. 1993 Sep;12(5):420–432. doi: 10.1097/00003226-199309000-00009. [DOI] [PubMed] [Google Scholar]
- Berman M., Leary R., Gage J. Evidence for a role of the plasminogen activator--plasmin system in corneal ulceration. Invest Ophthalmol Vis Sci. 1980 Oct;19(10):1204–1221. [PubMed] [Google Scholar]
- Busso N., Masur S. K., Lazega D., Waxman S., Ossowski L. Induction of cell migration by pro-urokinase binding to its receptor: possible mechanism for signal transduction in human epithelial cells. J Cell Biol. 1994 Jul;126(1):259–270. doi: 10.1083/jcb.126.1.259. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chou L., Firth J. D., Uitto V. J., Brunette D. M. Substratum surface topography alters cell shape and regulates fibronectin mRNA level, mRNA stability, secretion and assembly in human fibroblasts. J Cell Sci. 1995 Apr;108(Pt 4):1563–1573. doi: 10.1242/jcs.108.4.1563. [DOI] [PubMed] [Google Scholar]
- D'Alessio M., Ramirez F., Suzuki H. R., Solursh M., Gambino R. Cloning of a fibrillar collagen gene expressed in the mesenchymal cells of the developing sea urchin embryo. J Biol Chem. 1990 Apr 25;265(12):7050–7054. [PubMed] [Google Scholar]
- Damsky C. H., Werb Z. Signal transduction by integrin receptors for extracellular matrix: cooperative processing of extracellular information. Curr Opin Cell Biol. 1992 Oct;4(5):772–781. doi: 10.1016/0955-0674(92)90100-q. [DOI] [PubMed] [Google Scholar]
- Darby I., Skalli O., Gabbiani G. Alpha-smooth muscle actin is transiently expressed by myofibroblasts during experimental wound healing. Lab Invest. 1990 Jul;63(1):21–29. [PubMed] [Google Scholar]
- Desmoulière A., Geinoz A., Gabbiani F., Gabbiani G. Transforming growth factor-beta 1 induces alpha-smooth muscle actin expression in granulation tissue myofibroblasts and in quiescent and growing cultured fibroblasts. J Cell Biol. 1993 Jul;122(1):103–111. doi: 10.1083/jcb.122.1.103. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Deutsch D. G., Mertz E. T. Plasminogen: purification from human plasma by affinity chromatography. Science. 1970 Dec 4;170(3962):1095–1096. doi: 10.1126/science.170.3962.1095. [DOI] [PubMed] [Google Scholar]
- Frangieh G. T., Hayashi K., Teekhasaenee C., Wolf G., Colvin R. B., Gipson I. K., Kenyon K. R. Fibronectin and corneal epithelial wound healing in the vitamin A-deficient rat. Arch Ophthalmol. 1989 Apr;107(4):567–571. doi: 10.1001/archopht.1989.01070010581034. [DOI] [PubMed] [Google Scholar]
- Friedman S. L. Seminars in medicine of the Beth Israel Hospital, Boston. The cellular basis of hepatic fibrosis. Mechanisms and treatment strategies. N Engl J Med. 1993 Jun 24;328(25):1828–1835. doi: 10.1056/NEJM199306243282508. [DOI] [PubMed] [Google Scholar]
- Greenwel P., Iraburu M. J., Reyes-Romero M., Meraz-Cruz N., Casado E., Solis-Herruzo J. A., Rojkind M. Induction of an acute phase response in rats stimulates the expression of alpha 1(I) procollagen messenger ribonucleic acid in their livers. Possible role of interleukin-6. Lab Invest. 1995 Jan;72(1):83–91. [PubMed] [Google Scholar]
- Grinnell F. Fibroblasts, myofibroblasts, and wound contraction. J Cell Biol. 1994 Feb;124(4):401–404. doi: 10.1083/jcb.124.4.401. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hasty D. L., Hay E. D. Freeze-fracture studies of the developing cell surface. I. The plasmalemma of the corneal fibroblast. J Cell Biol. 1977 Mar;72(3):667–686. doi: 10.1083/jcb.72.3.667. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jarnagin W. R., Rockey D. C., Koteliansky V. E., Wang S. S., Bissell D. M. Expression of variant fibronectins in wound healing: cellular source and biological activity of the EIIIA segment in rat hepatic fibrogenesis. J Cell Biol. 1994 Dec;127(6 Pt 2):2037–2048. doi: 10.1083/jcb.127.6.2037. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jester J. V., Barry P. A., Lind G. J., Petroll W. M., Garana R., Cavanagh H. D. Corneal keratocytes: in situ and in vitro organization of cytoskeletal contractile proteins. Invest Ophthalmol Vis Sci. 1994 Feb;35(2):730–743. [PubMed] [Google Scholar]
- Jester J. V., Petroll W. M., Barry P. A., Cavanagh H. D. Expression of alpha-smooth muscle (alpha-SM) actin during corneal stromal wound healing. Invest Ophthalmol Vis Sci. 1995 Apr;36(5):809–819. [PubMed] [Google Scholar]
- Jester J. V., Petroll W. M., Barry P. A., Cavanagh H. D. Temporal, 3-dimensional, cellular anatomy of corneal wound tissue. J Anat. 1995 Apr;186(Pt 2):301–311. [PMC free article] [PubMed] [Google Scholar]
- Jester J. V., Petroll W. M., Feng W., Essepian J., Cavanagh H. D. Radial keratotomy. 1. The wound healing process and measurement of incisional gape in two animal models using in vivo confocal microscopy. Invest Ophthalmol Vis Sci. 1992 Nov;33(12):3255–3270. [PubMed] [Google Scholar]
- Khaw P. T., Schultz G. S., MacKay S. L., Chegini N., Rotatori D. S., Adams J. L., Shimizu R. W. Detection of transforming growth factor-alpha messenger RNA and protein in human corneal epithelial cells. Invest Ophthalmol Vis Sci. 1992 Nov;33(12):3302–3306. [PubMed] [Google Scholar]
- Kumar C. C., Bushel P., Mohan-Peterson S., Ramirez F. Regulation of smooth muscle alpha-actin promoter in ras-transformed cells: usefulness for setting up reporter gene-based assay system for drug screening. Cancer Res. 1992 Dec 15;52(24):6877–6884. [PubMed] [Google Scholar]
- Lauweryns B., van den Oord J. J., Volpes R., Foets B., Missotten L. Distribution of very late activation integrins in the human cornea. An immunohistochemical study using monoclonal antibodies. Invest Ophthalmol Vis Sci. 1991 Jun;32(7):2079–2085. [PubMed] [Google Scholar]
- Masur S. K., Cheung J. K., Antohi S. Identification of integrins in cultured corneal fibroblasts and in isolated keratocytes. Invest Ophthalmol Vis Sci. 1993 Aug;34(9):2690–2698. [PubMed] [Google Scholar]
- Masur S. K., Idris A., Michelson K., Antohi S., Zhu L. X., Weissberg J. Integrin-dependent tyrosine phosphorylation in corneal fibroblasts. Invest Ophthalmol Vis Sci. 1995 Aug;36(9):1837–1846. [PubMed] [Google Scholar]
- Montesano R., Orci L. Transforming growth factor beta stimulates collagen-matrix contraction by fibroblasts: implications for wound healing. Proc Natl Acad Sci U S A. 1988 Jul;85(13):4894–4897. doi: 10.1073/pnas.85.13.4894. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nakayasu K. Stromal changes following removal of epithelium in rat cornea. Jpn J Ophthalmol. 1988;32(2):113–125. [PubMed] [Google Scholar]
- Owens G. K., Loeb A., Gordon D., Thompson M. M. Expression of smooth muscle-specific alpha-isoactin in cultured vascular smooth muscle cells: relationship between growth and cytodifferentiation. J Cell Biol. 1986 Feb;102(2):343–352. doi: 10.1083/jcb.102.2.343. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pasquale L. R., Dorman-Pease M. E., Lutty G. A., Quigley H. A., Jampel H. D. Immunolocalization of TGF-beta 1, TGF-beta 2, and TGF-beta 3 in the anterior segment of the human eye. Invest Ophthalmol Vis Sci. 1993 Jan;34(1):23–30. [PubMed] [Google Scholar]
- Rizzino A., Kazakoff P., Ruff E., Kuszynski C., Nebelsick J. Regulatory effects of cell density on the binding of transforming growth factor beta, epidermal growth factor, platelet-derived growth factor, and fibroblast growth factor. Cancer Res. 1988 Aug 1;48(15):4266–4271. [PubMed] [Google Scholar]
- Rønnov-Jessen L., Petersen O. W. Induction of alpha-smooth muscle actin by transforming growth factor-beta 1 in quiescent human breast gland fibroblasts. Implications for myofibroblast generation in breast neoplasia. Lab Invest. 1993 Jun;68(6):696–707. [PubMed] [Google Scholar]
- Rønnov-Jessen L., Petersen O. W., Koteliansky V. E., Bissell M. J. The origin of the myofibroblasts in breast cancer. Recapitulation of tumor environment in culture unravels diversity and implicates converted fibroblasts and recruited smooth muscle cells. J Clin Invest. 1995 Feb;95(2):859–873. doi: 10.1172/JCI117736. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rønnov-Jessen L., van Deurs B., Celis J. E., Petersen O. W. Smooth muscle differentiation in cultured human breast gland stromal cells. Lab Invest. 1990 Oct;63(4):532–543. [PubMed] [Google Scholar]
- Sappino A. P., Schürch W., Gabbiani G. Differentiation repertoire of fibroblastic cells: expression of cytoskeletal proteins as marker of phenotypic modulations. Lab Invest. 1990 Aug;63(2):144–161. [PubMed] [Google Scholar]
- Streuli C. H., Schmidhauser C., Kobrin M., Bissell M. J., Derynck R. Extracellular matrix regulates expression of the TGF-beta 1 gene. J Cell Biol. 1993 Jan;120(1):253–260. doi: 10.1083/jcb.120.1.253. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WEIMAR V. The transformation of corneal stromal cells to fibroblasts in corneal wound healing. Am J Ophthalmol. 1957 Oct;44(4 Pt 2):173–182. doi: 10.1016/0002-9394(57)90445-2. [DOI] [PubMed] [Google Scholar]
- Wax S. D., Rosenfield C. L., Taubman M. B. Identification of a novel growth factor-responsive gene in vascular smooth muscle cells. J Biol Chem. 1994 Apr 29;269(17):13041–13047. [PubMed] [Google Scholar]
- Wilson S. E., Schultz G. S., Chegini N., Weng J., He Y. G. Epidermal growth factor, transforming growth factor alpha, transforming growth factor beta, acidic fibroblast growth factor, basic fibroblast growth factor, and interleukin-1 proteins in the cornea. Exp Eye Res. 1994 Jul;59(1):63–71. doi: 10.1006/exer.1994.1081. [DOI] [PubMed] [Google Scholar]
- Zambruno G., Marchisio P. C., Melchiori A., Bondanza S., Cancedda R., De Luca M. Expression of integrin receptors and their role in adhesion, spreading and migration of normal human melanocytes. J Cell Sci. 1993 May;105(Pt 1):179–190. doi: 10.1242/jcs.105.1.179. [DOI] [PubMed] [Google Scholar]