Identification of collagens synthesized by cultures of normal human corneal and keratoconus stromal cells

doi:10.1016/0304-4165(83)90233-7

Biochimica et Biophysica Acta (BBA) - General Subjects

Volume 755, Issue 3, 22 February 1983, Pages 318-325

https://doi.org/10.1016/0304-4165(83)90233-7 Get rights and content

Abstract

We have examined the collagens synthesized by cultures of normal human corneal stromal cells. Radioactively labeled products, accumulated in the culture medium during a 24-h labeling period, we treated with pepsin and analyzed by SDS-polyacrylamide gel electrophoresis. The cell layer collagen was characterized by 2.6 M and 4.4 M salt fractionation at neural pH, CM-cellulose column chromatography, SDS-gel electrophoresis, and cyanogen bromide peptide mapping. Type 1 α1 and α2 chains were the predominant components in both the cell layer and the medium fractions of normal human stromal cultures; type III collagen was found mostly in the culture medium; and type V collagen was associated with the cell layer. Immunofluorescent techniques used to visualize collagen deposition in the cell layer confirmed the presence of these collagen types. Keratoconus is a disease characterized by thinning and scarring of the central cornea. Stromal cells grown from keratoconus corneas produced similar types of collagen (types I, III, and V) as normal human controls. Cells from keratoconus patients, however, contained more type V collagen in the cell layer than did normal cells. The difference was seen only in the 4.4 M salt precipitates. Since type V collagen is one component of cell surfaces, the primary defect in cultures from keratoconus corneas could involve cell membrane and cell surface components.

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^∗: Present address: Department of Ophthalmology, University of Illinois, Eye & Ear Infirmary, Chicago, IL 60612, U.S.A.

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Identification of collagens synthesized by cultures of normal human corneal and keratoconus stromal cells

Abstract

Exp. Eye Res.

Exp. Eye Res.

J. Biol. Chem.

Albrecht von Graefes Arch. Klin. Exp. Ophthalmol.

Biochem. Biophys. Res. Commun.

Am. J. Ophthalmol.

Arch. Ophthalmol. (Paris)

J. Biol. Chem.

Biochemistry

Annu. Rev. Biochem.

N. Engl. J. Med.

N. Engl. J. Med.

Invest. Ophthalmol. Vis. Sci.

Biochim. Biophys. Acta

Invest. Ophthalmol. Vis. Sci.

Current Eye Res.

Invest. Ophthalmol. Vis. Sci.

Exp. Eye Res.