Study finds healthy-appearing lupus skin predisposed to flares, rashes

 People with lupus have overactive immune systems that attack their own tissue, causing inflammation throughout the body.

Around 70-80% of them will develop skin disease as part of their condition. And while it's thought that exposure to ultraviolet light triggers the rashes, scientists are not sure how it ties together with the systemic inflammation.

A Michigan Medicine study now brings more clarity, as researchers found that the normal-appearing skin of lupus patients contains the same inflammatory signals that are detected when the skin develops a rash -- sometimes at even higher levels. The results are published in Science Translational Medicine.

"This really starts to piece the puzzle together of how inflammation seen in lupus patients may be related to skin exposures such as UV light," said J. Michelle Kahlenberg, M.D., Ph.D., senior author of the study and rheumatologist at University of Michigan Health. "We were able to see the properties of normal-appearing skin in unparalleled resolution, suggesting that the skin is primed for inflammatory reactions."

The team of researchers used single-cell RNA-sequencing analysis to assess the biopsies of both normal-appearing skin and skin from rashes of seven lupus patients. The results reveal that elevated signals of interferon, a protein known to contribute to UV sensitivity, were robustly present in all lupus biopsies compared to healthy control skin -- with the strongest signal coming from the healthy-appearing skin, not the inflamed skin.

These interferon-rich inflammatory properties weren't just found in the keratinocytes, the cells that make up the epidermis of the skin. Researchers saw the same inflammatory changes in the fibroblasts that generate the connective tissue of the skin.

source :science daily