Plasminogen activator inhibitor type 2 is expressed in keratinocytes during re-epithelialization of epidermal defects

Br J Dermatol. 1998 Jan;138(1):22-8. doi: 10.1046/j.1365-2133.1998.02021.x.

Abstract

Plasminogen activation is observed in the human epidermis during re-epithelialization of epidermal defects. The activation reaction depends on plasminogen activators (PAs) associated with re-epithelializing keratinocytes. PA inhibitor type 2 (PAI-2) is thought to be a major epidermal PA inhibitor in keratinocytes. However, no data are available on the expression of PAI-2 in keratinocytes during epidermal regeneration. We have therefore analysed PAI-2 at the mRNA and protein level in keratinocyte cultures as well as in epidermal lesions in which re-epithelializing keratinocytes were apparent. We found that PAI-2 expression at the mRNA and protein level was negatively correlated with the cell density in regular keratinocyte cultures. In organotypic cocultures, in which the transition from a re-epithelializing to a sedentary phenotype can be studied, PAI-2 was most strongly expressed in early cultures prior to formation of a differentiated epidermis-like structure. We found a strong expression of PAI-2 in keratinocytes that re-epithelialized dermal burn wounds or lesions caused by the autoimmune blistering disease pemphigus vulgaris. Our results suggest that not only PAs, but also a major PA inhibitor, PAI-2, are expressed in keratinocytes that are actively involved in re-epithelialization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Northern
  • Burns / metabolism
  • Burns / pathology
  • Cell Culture Techniques
  • Epidermis / metabolism*
  • Epidermis / pathology
  • Epithelium / metabolism
  • Fluorescent Antibody Technique
  • Gene Expression
  • Humans
  • In Situ Hybridization
  • Keratinocytes / metabolism*
  • Male
  • Pemphigus / metabolism
  • Pemphigus / pathology
  • Plasminogen Activator Inhibitor 2 / genetics
  • Plasminogen Activator Inhibitor 2 / metabolism*
  • RNA, Messenger / genetics
  • Wound Healing / physiology*

Substances

  • Plasminogen Activator Inhibitor 2
  • RNA, Messenger