Porphyrin production by C. acnes and IL-1β released by HaCaT keratinocytes
(A) HPLC analysis of the C. acnes HL053PA1 porphyrin extract showing the presence of coproporphyrin I, coproporphyrin III, coproporphyrin III tetramethyl ester, and protoporphyrin IX.
(B) Amount of IL-1β released by HaCaT keratinocytes grown in a co-culture model with SZ95 sebocytes after infection with the acneic HL053PA1 strain for 48 h or after priming with 0.1 mg/mL LPS for 4 h followed by exposure to 0.5, 1.0, and 2.5 μM of the extracted porphyrins for 48 h.
(C) Fold change in IL-1β release by HaCaT cells, after adding 5-aminolevulinic acid (5-ALA) or succinyl acetone (SA) during infection with the acneic HL053PA1 strain.
(D) Fold change in IL-1β release after exposure to extracted porphyrins combined with albumin (AL) or hemopexin (HE), compared with the porphyrins extract only. Error bars represent standard error of the mean. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.005, ∗∗∗∗p < 0.001