One of the major research themes of the Vickaryous Laboratory is focused on identifying and understanding the biological mechanisms that permit and promote scar-free wound healing and tissue regeneration. The primary model for our studies is the leopard gecko, Eublepharis macularius, a lizard common in the pet trade. As for many lizards, leopard geckos are able to self-shed (or autotomize) a portion of their tail as an anti-predation strategy, and then spontaneously regenerate a replacement.

Dorsal views of an original tail (o) and the seven stages of normal tail regeneration (I-VII).  These stages can be broadly organized into phases of wound healing (stages I-III) and regenerative outgrowth (IV-VII).  Timeframe for regenerat… — Dorsal views of an original tail (o) and the seven stages of normal tail regeneration (I-VII). These stages can be broadly organized into phases of wound healing (stages I-III) and regenerative outgrowth (IV-VII). Timeframe for regeneration is 25-30 days. See McLean and Vickaryous (2011) and Delorme et al. (2012) for details.

Regeneration is initiated by inducing tail loss.   In our lab, tail loss (or caudal autotomy) is achieved by pinching the tail.  The distal portion of the tail is self-detached, whereas the proximal portion is retained.  This sequence… — Regeneration is initiated by inducing tail loss. In our lab, tail loss (or caudal autotomy) is achieved by pinching the tail. The distal portion of the tail is self-detached, whereas the proximal portion is retained. This sequence of images was taken by a camera at 28 frames per second. Click here to see the video.

Tail regeneration is independent from tail autotomy.

Following from our work in whole-tail multi-tissue regeneration, we have begun to study and manipulate wound healing. Unlike mammals, which typically scar, species capable of regeneration often have the ability to heal cutaneous wounds without scarring.

To study wound healing, geckos are deeply anaesthetized and a 3mm diameter full-thickness cutaneous excisional wound is created. Forty-five days later, the wound site is healed without scar formation. Instead, newly formed pigmented scales cover the wound site. Using this model, we are working to uncover the key processes in wound healing that promote a scarless outcome.