In a presentation at AAD 2022, Jack Arbiser, MD, PhD, FAAD, explained how improved knowledge of an intact skin barrier can help dermatologists better treat their patients who present with inflammatory disorders.

At the start of his session he said, “[M]y goal for this talk today is to simplify the basic science.”

He asked the audience, “Why should clinical dermatologists understand the barrier function of the skin?”

According to Dr Arbiser, virtually all inflammatory and malignancy disorders arise from chronic barrier defects. Additionally he said that skin has a unique sensing mechanism through ceramide release which ultimately helps identify inflammation.  

Dr Arbiser said there are three important things to maintain a healthy skin barrier. They include:

• energy;
• acid; and
• ceramides.

“The earlier the onset, he said, “the more likely genetics are involved and later onset implications environmental causes.”

He then explained and said that the skin barrier is important because, “the skin barrier keeps water in and noxious chemicals and organisms out. The outer layer is the stratum corneum—dead cells—but the visibility of all the layers is required for optimal barrier functions.

Of important note, Dr Arbiser explained that each layer of the skin is required in order to maintain optimal barrier function.

“The acid mantle concept, in which acidity of the skin is required for maintenance of the barrier function,” he said. “Decreased acidity leads to inflammation and infection.”

As many people know, he reminded the audience that most soaps and detergents are alkaline based. Further, he said, that ceramide-based lipids rapidly signal barrier disruption.

“The skin has a tonic level of Th1 inflammation maintained by IL-12,” Dr Arbiser said. “IL-12 suppresses Th2 mediated immunity and Th17 mediated immunity.”

Finally, Dr Arbiser explained to the audience that a consequence of aging is skin inflammation. Again he stressed that at birth or in utero, most cutaneous inflammation is not present.

“A combination of skin aging plus external influences result in inflammation,” Dr Arbiser said.  

Additionally, he added that defects in the dermis, such as a burn, can impair epidermal skin barrier.

“A defective dermis cannot support skin appendages or maintain adequate barrier function,” he said.

Reference:

Arbiser JL. Understand the skin barrier. Presented at: AAD Annual Meeting; March 25-28, 2022; Boston, MA.