TÁMOP-4.2.2/B-10/1-2010-0012 project: “Broadening the knowledge base and supporting the long term
professional sustainability of the Research University Center of Excellence at the University of Szeged by ensuring the rising generation of excellent scientists.”
Real-time monitoring of the effect of Propionibacterium acnes on the proliferation and viability of keratinocytes
Gábor Tax2 andKornélia Szabó1, Edit Urbán3, Lajos Kemény1,2 1. Dermatological Research Group of the Hungarian Academy of Sciences, Szeged, Hungary 2. Department of Dermatology and Allergology, University of Szeged, Hungary
3. Institute of Clinical Microbiology, University of Szeged, Hungary
Acne is a common multifactorial inflammatory skin disease of the pilosebaceous unit in which the Gram-positive Propionibacterium acnes (P. acnes) is an important pathogenic factor. It has been shown previously that selected P. acnes strains (889 and ATCC11828) belonging to various phylogenetic subgroups differentially affected the pro- liferation and viability of cultured normal human keratinocytes.
To investigate this phenomenon, we performed real-time label free monitoring of the effect of three P. acnes strains (889, 6609, ATCC 11828) on the proliferation and viability of immortalized human keratinocytes (HPV- KER), using a novel, impedance measurement‑based technology. To analyze whether the effect of the microbe on the HPV-KER cells was dose dependent, we applied the bacterium at different ratios (multiplicity of infection = MOI: 25, 50, 100, 200 and 300).
Addition of P. acnes 889 strain at high MOIs (200,300) induced a rapid increase in the measured impedances compared to the untreated control cells. This effect was due to increased cell proliferation of the HPV-KER cells.
The P. acnes 6609 strain had no effect on cell proliferation, whereas the HPV-KER cells stopped proliferating in response to the ATCC 11828 treatment. At later time-points (24-36 h after the bacterial treatment) the imped- ance values showed a rapid decrease in the P. acnes 889 and ATCC 11828 treated cultures, using high MOIs (200, 300) due to the death of the HPV-KER cells.
These results suggest that assorted P. acnes strains have different effects on the proliferation and viability of keratinocytes, and strain specific differences may also be important for determining the severity of individual in- flammatory skin symptoms.
