Immunoguided cutaneous regeneration: a theoretical framework linking extracellular matrix, immunity, and skin...

Adult human skin healing is predominantly characterized by fibrosis rather than true regeneration, despite the conserved regenerative principles observed in fetal wound healing, liver regeneration, and other biological systems. Historical and contemporary observations in skin allotransplantation, including studies describing the differential behavior of the epidermis and dermis and recent experience with Cryopreserved Total Skin Allografts (CTSA), reveal a recurring biological pattern in which the epidermis is progressively eliminated while the dermal extracellular matrix remains relatively preserved. These observations suggest that immune-mediated tissue remodeling and regeneration may coexist during graft development. Here, we propose Immunoguided Cutaneous Regeneration (ICR) as a biologically plausible and experimentally testable conceptual framework to explain these observations. ICR proposes that regeneration associated with certain skin allografts depends not on prolonged donor cell survival but rather on the convergence of a preserved dermal extracellular matrix and a regulated alloimmune response, neither of which is proposed to be sufficient in isolation. Within this framework, the graft is proposed to function primarily as a transient instructive microenvironment, guiding recipient cell recruitment, matrix remodeling, and tissue reorganization. The process is organized into four partially overlapping phases: biological barrier, immune activation and cellular colonization, selective epidermal elimination, and regenerative remodeling. Therefore, regeneration is interpreted as a context-dependent emergent property of the matrix-host system, arising when a preserved extracellular matrix and a regulated, resolving alloimmune response converge within a permissive biological environment. ICR integrates previously fragmented historical, experimental, and clinical observations into a coherent mechanistic model that bridges the fields of transplantation immunology, extracellular matrix biology, and regenerative medicine. Although the available evidence does not establish causality, it is consistent with the proposed framework and supports its biological plausibility of the framework. Importantly, the theory generates explicit and potentially falsifiable predictions that distinguish it from alternative explanations and provide a structured conceptual foundation for future experimental investigations. If validated, ICR may redefine skin allotransplantation not only as a model of immune rejection but also as a model of context-dependent tissue regeneration, providing a conceptual basis for understanding how immunity, extracellular matrix biology, and tissue architecture collectively determine the balance between fibrosis and regeneration.