Submission Date


Document Type

Paper- Restricted to Campus Access



Faculty Mentor

Ellen Dawley


Presented during the 22nd Annual Summer Fellows Symposium, July 24, 2020 at Ursinus College.

A related presentation is available here.

Project Description

Setting the precedent for regenerative biology, the axolotl (Ambystoma mexicanum) faithfully reconstructs its spinal cord following injury. With application to neural regeneration and paralysis treatment in humans, research on this phenomenon has spanned the last 50 years. Early research began with anatomical investigations, considering the emergence of stem cells at wound sites, but within the current millennium, focus has shifted to regeneration’s biochemical underpinnings, including cytokine-mediated inflammatory responses and neurotrophin-directed axonal growth. Microglia—the central nervous system’s phagocytic immune cells—have emerged as cytokine and neurotrophin signaling platforms, such that they foster a pro-regenerative environment following spinal cord injury. Accordingly, this study characterized microglia after spinal cord injury. Initially, we amputated 20% of an axolotl’s tail to induce a regenerative immune response, and then we amputated an additional 20% of the tail in the days following initial insult. Using tomato lectin, we labeled microglia in the sampled tissue sections, enumerated them with respect to the wound site, and characterized them according to active (amoeboid) or scanning (ramified) morphologies. In associating active microglia with the injury site, we aim to fortify the role of microglia in spinal cord regeneration, implying that they establish a pro-regenerative environment at the wound site, and that they actively mold axonal associations between residual and regenerated neurons.


Available to Ursinus community only.