Recellularized

Recellularized is an adjective used in regenerative medicine and tissue engineering to describe a biomaterial, scaffold, or organ that has been repopulated with living cells after decellularization. In decellularization, cellular components are removed from a tissue while preserving the extracellular matrix (ECM), which provides structural and biochemical cues for cell attachment and function. A recellularized construct aims to restore tissue-specific cellularity and, ideally, function.

Recellularization typically involves selecting an appropriate scaffold source, seeding cells onto or within the ECM, and cultivating the construct in static conditions or in a bioreactor that provides perfusion, oxygenation, and mechanical stimulation. Cell types used include endothelial cells for vasculature, parenchymal cells for organ-specific functions, and supporting stromal cells. The goal is to achieve uniform cell distribution, integrated vascular networks, and sustained viability.

Applications include engineering of whole organs or tissue patches, such as liver, heart, lung, kidney, or tracheal substitutes, as well as vascular grafts and skin. Recellularized constructs are studied as potential alternatives to conventional transplantation and as platforms for disease modeling, drug screening, and basic research on cell-ECM interactions.

Current status: recellularization is largely experimental for whole organs, with limited clinical translation to date. Key challenges include achieving full functional maturation, scalable production, immune compatibility, and reliable vascular perfusion. Ongoing research focuses on improving scaffold preservation, cell sourcing from iPSCs or primary cells, and bioreactor technologies to promote tissue integration after implantation.