Matrix Remodelling and MMP Expression/Activation Are Associated with Hidradenitis Suppurativa Skin Inflammation

The study investigated the inflammatory response in hidradenitis suppurativa (HS) skin using an ex vivo model with nine skin biopsy specimens. It found that HS skin exhibited significant matrix remodeling, characterized by changes in collagen I and III organization and increased elastin fiber fragmentation. This remodeling was linked to elevated levels of MMP-2 and MMP-9 in HS lesional skin. After 4 days of culture, MMP expression in HS perilesional skin matched that of lesional skin, and IL-1β concentrations increased in all samples, remaining higher in HS lesional skin compared to controls. However, IL-17 and inflammasome components NLRP3 and caspase-1 did not vary. The findings suggested that MMP-induced matrix alterations could contribute to HS inflammation by releasing active peptides and inflammatory factors from the extracellular matrix, offering new insights into the inflammatory mechanisms of HS.