Tissue repair and regeneration with endogenous stem cells

Summary

This review examines whether tissue-resident adult stem cells can be mobilized to repair mammalian organs without transplanting externally expanded cells. It contrasts the comparatively weak regenerative capacity of mammals with that of non-mammalian vertebrates, then surveys endogenous stem-cell populations and the specialized niches that regulate their self-renewal, migration, and differentiation. A central approach is to recreate or modify those niches with natural or synthetic biomaterial scaffolds. Because such scaffolds can be shaped and furnished with biochemical and mechanical signals, they may provide spatial and temporal instructions that activate local cells and guide tissue formation. The review also considers interspecies chimaeras as a separate regenerative strategy. Its principal conclusion is that endogenous stem cells already participate in repair and remodelling, and that biomaterials could make this activity more therapeutically useful by supplying missing niche cues. This framework is significant because it favors in situ regeneration and may avoid some burdens of cell harvesting and transplantation. However, the abstract describes a broad conceptual review rather than a systematic evidence synthesis, reports no comparative clinical outcomes, and does not establish which scaffold designs are safe, durable, or effective in humans.