Establishment of an Anti-acne Vulgaris Evaluation Method Based on TLR2 and TLR4-mediated Interleukin-8 Production

Abstract

Background/aim: To date, no cell-based assay that focuses on the prime cause of acne initiation through activation of toll-like receptor2 and 4 and interleukin-8 (IL-8) production exists. Herein, we present an assay that evaluates acne by determining TLR2 and 4 expression and activation.

Materials and methods: Viability of keratinocytes was determined by the MTT assay. IL-8 was evaluated by ELISA. Immunocytochemistry was performed for determining receptor expression.

Results: Lipoteichoic acid (LTA), peptidoglycan (PGN) and lipopolysaccharide (LPS) induced IL-8 production. Pre-treatment of cells with TLR2 and TLR4 inhibitors, before stimulation, reduced IL-8 production. Zinc gluconate was used for verification. Zinc can significantly suppress IL-8 production in the system. Treatment of cells with LTA+PGN or LPS resulted in increased TLR2 and TLR4 expression on the cell surface. This effect was prevented by zinc treatment.

Conclusion: The measurement of IL-8 and TLR2 and TLR4 levels can be used for the evaluation of anti-acne treatment.

Keywords: Acne vulgaris; IL-8; TLR2; TLR4; host defense; keratinocytes.