TY - CHAP M1 - Book, Section TI - Immunology of Skin Aging A1 - Vandiver, Amy R. A1 - Kim, Jenny A2 - Baumann, Leslie S. A2 - Rieder, Evan A. A2 - Sun, Mary D. Y1 - 2022 N1 - T2 - Baumann’s Cosmetic Dermatology, 3e AB - SUMMARY POINTSWhat’s ImportantThe skin provides the first line of defense against external pathogens through a physical, chemical, and antimicrobial barrier maintained by the epidermis and the cutaneous microbiome.In addition to barrier function, the skin acts as an innate immune sentinel, with Toll-like receptors responding to external pathogens and cellular damage to activate the local immune response.Cytokines and growth factors released upon activation of innate immune signaling regulate local inflammation and function of resident skin cells. Growth factors specifically play an important role in regulating epidermal proliferation and synthesis of the dermal matrix.Aging of the skin is associated with a decline in barrier function and increased activation of the innate immune system. These changes contribute to altered growth factor and MMP signaling which impair maintenance of the dermal matrix.What’s NewAdvances in sequencing technology have allowed increased insight into the diversity of the cutaneous microbiome. The balance of bacterial species and strains in each body site plays a role in regulating immune function.Induction of innate immune signaling through activation of Toll-like receptors as part of a damage response plays an important role in regeneration and wound healing.Anti-aging treatments targeted at modulating innate immune signaling have shown benefit for improving photoaging phenotypes.What’s ComingTherapy aimed at restoration of the skin barrier will clarify the role of skin barrier changes in initiating skin and systemic aging changes.Better characterization of the cutaneous microbiome will facilitate understanding of shifts associated with aging to offer more targeted probiotic therapy for cutaneous aging.Increased understanding of the role of the innate immune system in injury-mediated regeneration will offer new targets for promoting rejuvenation. SN - PB - McGraw Hill LLC CY - New York, NY Y2 - 2024/11/09 UR - dermatology.mhmedical.com/content.aspx?aid=1190667468 ER -