Full Name

Karen Echeverri

Throughout human life, many cells such as hair follicles and certain tissues such as liver can be continuously replaced to maintain tissue integrity in response to normal, daily wear and tear. However, the human response to more serious tissue damage, such as acute damage to limbs or to the spinal cord, is limited to relatively simple wound healing, whereby collagenous scar tissue fills the injury site, assuring the tissue’s structural integrity but often resulting in a debilitating loss of functional activity. While humans do exhibit some very limited regenerative capacity (e.g. liver), other animals exhibit sometimes astonishing regenerative ability.

Salamanders show the highest diversity in being able to regenerate limbs, tail, heart, eyes and jaw, and in addition can repair lesions in the brain and heal all wounds without forming scar tissue.

Our group has three main areas of research; the first is to understand at the molecular and cellular level how salamanders can regenerate a fully functional spinal cord after injury. In particular we focus on how the neural progenitor cells react to an injury signal and are activated to repair the lesion instead of forming inhibitory scar tissue. We aim to understand how these stem cells are guided to replace the correct number of lost neurons and reconnect the circuits to regain motor and sensory control.

The second main focus of the lab is on scar free wound healing. Axolotls regenerate without the formation of scar tissue. Our longstanding work on the “axolotl” salamander, the champion among such species, is identifying critical molecules, regulatory pathways and cellular processes underlying scar-free regeneration. We use transcriptional profiling and in vivo imaging to understand which cells respond to the injury signal, what the potential of these cells is and where cells come from to heal the wounds scar free.

The third area of research in the lab is the evolution of regenerative ability. We are using the local invertebrate sea anemone, Nematostella vectensis that has the natural ability to regenerate and adapt quickly to changing environmental conditions, to interrogate pathways conserved in invertebrates and vertebrate species, to begin to elucidate regulatory networks necessary to initiate and terminate regenerative growth.