The UCLA study conducted with researchers at Washington University and the Los Angeles Biomedical Research Institute looked into Propionibacterium acnes, bacteria that thrive in the oily depths of our pores, and found that while ‘bad’ strains result in spots, ‘good’ strains may protect the skin.
This could lead to new formulations being developed for skin creams and lotions that increase the body's friendly strain of P. acnes.
"This P. acnes strain may protect the skin, much like yogurt's live bacteria helps defend the gut from harmful bugs," says lead author Huiying Li, assistant professor at UCLA.
"Our next step will be to investigate whether a probiotic cream can block bad bacteria from invading the skin and prevent pimples before they start."
In their study, published in the Journal of Investigative Dermatology, Li’s team found that one strain of P. acnes may actually help keep skin healthy.
Using over-the-counter pore-cleansing strips, LA BioMed and UCLA researchers lifted P. acnes bacteria from the noses of 49 pimply and 52 clear-skinned volunteers.
After extracting the microbial DNA from the strips, Li's laboratory tracked a genetic marker to identify the bacterial strains in each volunteer's pores, recording whether the person suffered from acne, before culturing the bacteria from the strips to isolate more than 1,000 strains.
Different strains for different gains
"We were interested to learn that the bacterial strains looked very different when taken from diseased skin, compared to healthy skin," said co-author Dr. Noah Craft, a dermatologist and director of the Center for Immunotherapeutics Research at LA BioMed.
"Two unique strains of P. acnes appeared in one out of five volunteers with acne but rarely occurred in clear-skinned people."
The team also uncovered a third strain of P. acnes that's common in healthy skin yet rarely found when acne is present, that Li suggests contains a natural defence mechanism that enables it to recognize attackers and destroy them before they infect the bacterial cell.
The researchers say that future studies will focus on exploring new drugs that kill bad strains of P. acnes while preserving the good ones; the use of viruses to kill acne-related bacteria; and a simple skin test to predict whether a person will develop aggressive acne in the future.
Sorel Fitz-Gibbon, Shuta Tomida, Bor-Han Chiu, Lin Nguyen, Christine Du, Minghsun Liu, David Elashoff, Marie C Erfe, Anya Loncaric, Jenny Kim, Robert L Modlin, Jeff F Miller, Erica Sodergren, Noah Craft, George M Weinstock, Huiying Li. Propionibacterium acnes Strain Populations in the Human Skin Microbiome Associated with Acne.Journal of Investigative Dermatology, 2013; DOI:10.1038/jid.2013.21