The sebum, which is produced in the follicle normally, flows to the skin surface via
a canal. The canal is also used to remove dead cells shed by the walls of the
follicle. In acne the canal becomes plugged with increased amounts of sebum and
cellular debris. Within the plugged area, high levels of bacteria, Proprionibacterium
Acnes (P. acnes), are found. Enzymes from the bacteria split the sebum into free
fatty acids that are highly irritating to the skin. When a break in the cell wall
occurs, the free fatty acid and cellular debris cause inflammatory reactions of
varying degrees.