Fibronectin matrix deposition and fibronectin receptor expression in healing and normal skin.

Abstract

During cutaneous tissue organization, numerous critical interactions occur between cells and the extracellular matrix (ECM). Cell-matrix interactions depend on the presence of ECM receptors. Many ECM receptors, known as integrins, are heterodimeric glycoproteins consisting of one alpha and one beta chain. Integrins containing beta 1 or beta 3 chains are ECM receptors, whereas those containing beta 2 chains are leukocyte cell-cell receptors. We have used porcine cutaneous wounds as a paradigm for tissue organization and probed healing wounds and adjacent normal skin with polyclonal antibodies to fibronectin and fibronectin (alpha 5 beta 1) receptor. During re-epithelialization, the epidermis transits over a provisional matrix containing fibronectin. Migrating epidermal cells expressed fibronectin receptors in a bright linear peripheral pattern. At 10 days, when reepithelialization was complete and the basement membrane was re-established, the fibronectin matrix was markedly reduced and fibronectin-receptor expression was limited to the basolateral aspect of basal cells, as observed in normal epidermis. Beneath the migrating epidermis in 5-d wounds, granulation tissue had filled 80% of the wound space. Day-5 wound fibroblasts did not express fibronectin nor other beta 1 integrin receptors, were randomly oriented, and contained no actin bundles. Fibronectin fibrils were assembled on the surfaces of day-5 wound fibroblasts but formed few linkages between cells. Day-7 wound fibroblasts expressed fibronectin receptors, contained peripheral cytoplasmic actin bundles consistent with a contractile fibroblast phenotype, and were coaligned across the wound in parallel array with interconnecting fibronectin fibrils. The wounds contracted between 7 and 10 days. Thus the migrating epidermis consistently expressed fibronectin receptors. Fibronectin receptors were expressed by fibroblasts just prior to wound contraction.

• Authors: R A Clark
• Journal: The Journal of investigative dermatology (J Invest Dermatol) Vol. 94 Issue 6 Suppl Pg. 128S-134S (Jun 1990) ISSN: 0022-202X [Print] United States
• PMID: 2161886 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S., Review)

Chemical References

• Fibronectins
• Integrins
• Receptors, Cell Surface
• Receptors, Fibronectin
• Receptors, Immunologic

Topics

• Animals
• Extracellular Matrix (metabolism)
• Fibronectins (metabolism)
• Humans
• Integrins (metabolism)
• Receptors, Cell Surface (metabolism)
• Receptors, Fibronectin
• Receptors, Immunologic (metabolism)
• Skin (injuries, metabolism)
• Wound Healing (physiology)