Semiquantitative und quantitative Charakterisierung der Zytokinantwort humaner Keratinozyten nach Stimulation mit Propionibacterium acnes und Koproporphyrin III

Background The inflammation in acne vulgaris is widely thought to
be induced by an immunological reaction to Propionibacterium acnes.
Objectives In the present study we examined the local host response
mechanism of keratinocytes 3 and 6 h after stimulation with viable
and heat- killed P. acnes. Methods The quantitative expression of
cytokines was measured at the mRNA level by real time RT-PCR.
Results The co-incubation of keratinocytes with active, but not
heat- killed, P. acnes modulated an adequate cytokine response for
IL-1beta, GM-CSF, and IL-8. High-performance liquid chromatography
analysis of the in vivo porphyrin pattern secreted by P. acnes
revealed a predominance of coproporphyrin III in inflammatory acne
lesions. This same porphyrin fraction also modestly induced IL-8
expression by keratinocytes. Conclusions This cytokine pattern may
favor a chemotactic response and implicates P. acnes and
coproporphyrin III in the recruitment of leukocytes to the site of
infection and in the development of inflammatory lesions.