Humans and other mammals normally cannot regrow lost limbs, while animals such as salamanders can rebuild whole appendages. A new paper in Nature Communications from Texas A&M describes experiments that uncover a hidden regenerative capacity in mammalian healing. Ken Muneoka led the team.
Researchers developed a two-step protocol using two growth factors. They applied fibroblast growth factor 2 (FGF2) after the wound had closed; this stimulated formation of a blastema-like tissue, a structure typically seen in regenerative species. Several days later the team applied bone morphogenetic protein 2 (BMP2), which encouraged the blastema-like cells to begin forming new structures.
The treatment restored many components removed during amputation, including bone, joint structures, tendon, ligament and other connective tissues. The tissues were not exact replicas, but they reproduced skeletal and connective elements in an organized, natural way. The experiments used multiple biological pathways and did not require adding external stem cells. Because BMP2 is already FDA approved for some uses and FGF2 is in trials, researchers say the method could move faster toward clinical exploration to reduce scarring and improve repair.
Difficult words
- regrow — to grow back after being lost or removed
- appendage — a body part that extends from the main bodyappendages
- growth factor — a protein that helps cells grow and dividegrowth factors
- blastema-like tissue — a mass of cells that can form new parts
- amputation — surgical removal of a limb or body part
- scarring — formation of scar tissue during healing
- connective tissue — tissue that connects and supports body partsconnective tissues
- protocol — a planned series of medical steps or procedures
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Discussion questions
- How might a treatment that reduces scarring change recovery after an injury?
- Would you prefer a therapy that uses growth factors rather than added stem cells? Why or why not?
- What challenges do you think doctors might face if this method moves to clinical use?
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