α-Smooth muscle actin is expressed in a subpopulation of cultured and cloned fibroblasts and is modulated by γ-interferon

doi:10.1016/0014-4827(92)90348-C

Experimental Cell Research

Volume 201, Issue 1, July 1992, Pages 64-73

https://doi.org/10.1016/0014-4827(92)90348-C Get rights and content

Abstract

Clinical and experimental investigations have shown that, during wound healing and fibrocontractive diseases, fibroblasts acquire, more or less permanently according to the situation, morphological and biochemical features of smooth muscle (SM) cells including the expression of α-SM actin. Primary and passaged cultures of rat and human fibroblasts contain a subpopulation of cells expressing α-SM actin. These cells could derive from SM cells and/or pericytes present in the tissue from which cultures have been produced or represent bona fide fibroblasts. We have investigated the presence of α-SM actin in fibroblast cultures, clones, and subclones. In all cases the fibroblastic populations studied showed a proportion of α-SM actin expressing cells. Even after cloning, we never obtained populations negative for α-SM actin. We conclude that α-SM actin expression in fibroblastic cultures is not due to contaminant cells but is a feature of fibroblasts themselves. Our results support the view that fibroblastic cells are a heterogeneous population. It has been previously shown that γ-interferon (γ-IFN) decreases α-SM actin expression in SM cells. In rat and human fibroblasts, γ-IFN decreases α-SM actin protein and mRNA expression as well as proliferation. The properties of this cytokine make it a good candidate for exerting an anti-fibrotic activity in vivo.

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^☆: This work was supported in part by the Swiss National Science Foundation, Grant 31-30796.91.

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α-Smooth muscle actin is expressed in a subpopulation of cultured and cloned fibroblasts and is modulated by γ-interferon☆

Abstract

Int. Rev. Cytol

J. Mol. Biol

Anal. Biochem

Differentiation

Exp. Cell Res

Exp. Cell Res

Biochem. Biophys. Res. Commun

Coll. Res

Differentiation

Differentiation

Blood

Experientia

Am. J. Pathol

J. Cell Biol

Eur. J. Biochem

Nature

Lab. Invest

Lab. Invest

Am. J. Pathol

J. Exp. Med

EMBO J

J. Gen. Virol

J. Biol. Response Modif

Lab. Invest

Cell Motil. Cytoskeleton

Nature

Circ. Res

Biochemistry

Differentiation

Nucleic Acids Res

Molecular Cloning. A Laboratory Manual

J. Cell. Physiol

J. Cell. Physiol

Lab. Invest

Anat. Embryol

Immunol. Res