Granulocyte activating factor released from Propionibacterium acnes. A possible mediator of inflammation in acne vulgaris.

Incubation of Propionibacterium acnes but not of Propionibacterium granulosum or Propionibacterium avidum (for 30 min at 37 degrees C in physiological saline) released a soluble factor that produced enhanced chemiluminescence response of human granulocytes as well as increased chemotactic motility of these cells. Sephadex G-25 filtration of the granulocyte activating factor (GAF) revealed its low molecular weight and apparent peptide character. Thus, GAF may be a stimulus for inflammation in acne vulgaris since low molecular weight chemotactic factors can be expected to penetrate follicular walls.