Mammals May Possess Latent Regenerative Abilities

New research suggests that mammals, including humans, may possess a hidden capacity for regeneration, which could be activated under specific conditions. Scientists at the Texas A&M College of Veterinary Medicine and Biomedical Sciences (VMBS) developed a two-stage treatment that enabled the regeneration of bone, joint structures, and ligaments in animal studies. This finding challenges the long-held belief that mammals are fundamentally limited to healing injuries with scar tissue.

The study, published in *Nature Communications*, details how researchers redirected the body's natural healing response. Normally, when mammals are injured, fibroblast cells form scar tissue in a process called fibrosis. The research team instead guided these cells to form a blastema-like structure, similar to those seen in regenerating animals like salamanders. This redirection was achieved using a sequential application of two growth factors.

The treatment involved applying fibroblast growth factor 2 (FGF2) after the initial wound healing was complete. This encouraged the formation of the blastema-like structure. Several days later, bone morphogenetic protein 2 (BMP2) was applied, signaling the cells to build new tissues. This two-step process effectively shifted the cells away from scarring and towards regeneration, according to the researchers.

An important aspect of the study is the finding that regeneration may not require external stem cell introduction. The cells capable of regeneration appear to be already present at the injury site. The research indicates that these existing cells can be reprogrammed to behave in a regenerative manner. This suggests that the capacity for regeneration is not absent in mammalian cells but rather obscured.

Although the regenerated tissues were not perfect replicas, they successfully restored major structures lost during amputation, including bone, tendons, ligaments, and joint tissue. The regenerated areas contained skeletal components and connective tissues arranged in patterns resembling natural anatomy. This approach could potentially improve healing outcomes by reducing scar formation and enhancing tissue repair, even before full regeneration becomes possible.

Both BMP2 and FGF2 are already in clinical use or trials, which could streamline the path to clinical testing for this regenerative approach. The study provides a new framework for understanding mammalian regeneration, suggesting it is a dormant capability that can be activated. This opens new avenues for research into how to harness these latent regenerative powers.