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Published on: July 14, 2017

Modulation of integrins and filaggrin expression by Propionibacterium acnes extracts on keratinocytes

V Jarrousse1, N Castex-Rizzi, A Khammari

  • 1INSERM U601, 9 quai Moncousu, 44093 Nantes Cedex 01, France.

Archives of Dermatological Research
|August 9, 2007
PubMed

Insights

Propionibacterium acnes extracts significantly increase beta1 integrin and filaggrin expression in keratinocytes. This suggests the bacteria influences acne development beyond inflammation, potentially impacting microcomedo formation.

Area of Science:

  • Dermatology
  • Microbiology
  • Cell Biology

Background:

  • Propionibacterium acnes (P. acnes) is implicated in acne vulgaris pathogenesis, particularly the inflammatory phase.
  • The role of P. acnes in keratinocyte differentiation and early acne lesion formation remains incompletely understood.

Purpose of the Study:

  • To investigate the in vitro effects of P. acnes extracts on integrin and filaggrin expression in human keratinocytes.
  • To explore P. acnes's potential role in modulating keratinocyte differentiation and microcomedo development.

Main Methods:

  • Immunohistochemistry was used to assess integrin and filaggrin expression on Normal Human Epidermal Keratinocytes (NHEK) and human skin explants treated with P. acnes extracts.
  • Western-blot analysis was performed on acne lesion biopsies to evaluate filaggrin and profilaggrin levels.

Main Results:

  • P. acnes extracts significantly upregulated beta1 integrin expression in both proliferating and differentiated keratinocytes.
  • Increased expression of alpha3, alpha6s, alphaVbeta6 integrins, and filaggrin was observed in differentiated keratinocytes.
  • P. acnes extracts enhanced filaggrin expression in the suprabasal epidermis of skin explants, confirmed by western-blot.

Conclusions:

  • P. acnes extracts directly modulate keratinocyte differentiation by altering integrin and filaggrin expression.
  • These findings suggest P. acnes contributes to acne pathogenesis not only through inflammation but also potentially in the formation of microcomedones.

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