Advancing preclinical research with reconstructed in vitro skin models mimicking non-healing wounds

Chronic skin wounds remain a significant therapeutic challenge worldwide, primarily due to persistent inflammation, impaired function of fibroblasts and keratinocytes, defective angiogenesis, and the presence of complex polymicrobial biofilms. Conventional animal models only partially capture these human-specific pathophysiological mechanisms, limiting their predictive value for pharmacological development. Recent advances in human 3D in vitro skin models, including reconstructed human epidermis, full-thickness skin equivalents, vascularized and innervated constructs, and chronic wound-derived cell systems, provide opportunities to evaluate therapeutic strategies under controlled, human-relevant conditions. Here, we critically synthesize how engineered skin platforms recreate key pathological hallmarks of non-healing wounds, including IL-1/TNF-α-driven inflammation, RAGE-NOX4-mediated oxidative stress, MMP/TIMP imbalance, fibroblast and keratinocyte senescence, impaired HIF-1α/VEGF-dependent angiogenesis, immune polarization defects, and biofilm-associated antimicrobial tolerance. We examine scaffold-based, decellularized, and bioprinted approaches that enable the incorporation of adipocytes, endothelial cells, sensory neurons, and immune compartments, enhancing the mechanistic resolution with which chronic wound biology can be interrogated. By integrating cellular, biochemical, immune, vascular, and microbial components, next-generation models allow pharmacological interrogation of targets such as IL-1/IL-1R, IL-6/STAT3, TNF-α/TNFR, RAGE-NOX4, Nrf2/KEAP1, ERK/AKT, Ang/Tie2, ferroptosis regulators, senescence pathways, and neuroimmune modulators. Collectively, these platforms bridge the gap between reductionist assays and clinical complexity, offering a rational framework for mechanism-based drug discovery and preclinical screening. This review provides guidelines for selecting and designing advanced human skin models to accelerate the development of effective therapeutics for chronic non-healing wounds.