---

Leptin: integrator of immune response and regeneration

One of the major remaining hurdles to understanding why humans cannot regenerate appendages like hands and fingers is understanding how the initial immune response at the wound site prevents regeneration from occurring. Fetal mammals can regenerate more types of tissue than adults but they also heal differently. In order to understand how immune system development affects regeneration, I use the South African clawed frog (Xenopus laevis) as a model organism. These frogs have an immune system that is very similar to humans and also lose the ability to regenerate as the immune system matures. My project focuses on the role of leptin, an important immune system modulator, in integrating the immune responses necessary for regeneration and how its role in regeneration might change with immune system development. I have shown that leptin receptor is expressed differently before and after metamorphosis, the time point that regenerative ability becomes almost nonexistent. My project is focused on establishing direct roles of leptin as an immune integrator of regeneration at different points in immune system development. This will help us to better understand what parts of the immune system are important for regeneration and which prevent regeneration, with important applications in therapies for increasing human regeneration and healing from traumatic injuries.