Thomas Leung, M.D., Ph.D., Assistant Professor of Dermatology at Penn, along with research specialist, Casey Spencer, and graduate student, Mailyn Nishiguchi, worked together to understand why scarring is less prevalent in older skin than younger skin. They discovered that the younger the skin the more likely it is to scar than regenerate tissue, due to a specific protein in the blood, SDF1, which has higher levels in younger mice and humans. Older skin is more likely to regenerate than scar due to lower levels of SDF1 and higher levels of protein EZH2, which also inhibits SDF1. They published their findings in Cell Reports.
Dr. Leung theorizes that the reason younger skin scars is an evolutionary factor–a young injured animal needs to repair a wound quickly to survive and reproduce; older animals past their peak reproductive periods have more time to regenerate tissue.
Dr. Leung’s lab studies how human tissue heals without scarring. This discovery allows him to further research the proteins and ways to prevent scarring and promote tissue regeneration. As noted in an article Dr. Leung wrote for The Conversation and reprinted in the LA Times, “Taken together, we identified a rare example where aging improves tissue function, specifically the tissue repair process. We are planning a clinical trial with the drug, plerixafor, an existing FDA-approved SDF1 inhibitor which is currently used to mobilize stem cells for bone marrow transplant patients, to test its efficacy in preventing scar formation in humans.”
