Netherton syndrome is aggravated by the presence of two common Staphylococcal bacteria living on human skin, one of which was previously thought to only offer protective properties, according to a study conducted by researchers at the University of California San Diego School of Medicine.
In a study published online in Cell Reports (Mar. 3, 2020), the study’s senior author, Dr. Richard Gallo and his research team identified how Staphylococcus aureus and Staphylococcus epidermidis can act as a catalyst for skin inflammation and barrier damage in mouse models.
Netherton syndrome is a rare skin disease caused by a single genetic mutation.
“Our study shows how closely tied the human genome is to the genetic information in our skin microbiome. This rare disease is due to a mutation in a human gene. But, in adults, the symptoms of the disease are driven by the skin microbiome,” said Dr. Gallo in a press release. Dr. Gallo is an Irma Gigli distinguished professor and chair of the department of dermatology at UC San Diego’s School of Medicine.
“The two genomes work closely together. When one is off, even by a single gene, the other genome reacts.”
Researchers took skin swabs of 10 people with Netherton syndrome and found that their skin microbiome had an abundance of certain strains of S. aureus and S. epidermidis. But unlike the skin of normal subjects, the excess bacteria produced genes that could not be controlled due to the gene mutation in Netherton syndrome.
According to the National Institutes of Health, most people with this recessive inherited genetic disorder have immune system-related problems, such as food allergies, hay fever, asthma or eczema. It is estimated that 1 in 200,000 newborns are affected.
“In addition to demonstrating how an abnormal skin microbiome promotes inflammation in Netherton syndrome, this study provides one of the most detailed genomic descriptions to date of the skin microbiome,” said Dr. Gallo.
S. aureus is known to aggravate skin conditions, such as atopic dermatitis. Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of death resulting from infection in the United States.
On the other hand, S. epidermidis is commonly found on healthy human skin and presumed benign. In a previous study Dr. Gallo reported that a specific strain of S. epidermidis seemed to hold a protective property by secreting a chemical that kills several types of cancer cells but does not appear to be toxic to normal cells.
S. epidermidis was also known to promote wound repair, skin immunity and limit pathogen infections. It was not known that, in some cases, S. epidermidis can have pathogenic effects.