Poster #079, Charles R. Drew University of Medicine and Science
Investigating Blastema Formation in the Non-Regenerating Tails of Crested Geckos (Correlophus ciliatus)
Mentor: Thomas Lozito, PhD
A vast majority of lizards are capable of epimorphic regeneration, specifically in their tails, due to complex adaptations. Their regeneration is characterized by blastema formation, a mass of proliferating cells that reform lost tissues. Lizards are valuable models for understanding mammals’ inability to regenerate epimorphically, as they are the closest relatives of mammals capable of multilineage blastema-based regeneration. Despite widespread regenerative ability, crested geckos (Correlophus ciliatus) undergo tail autotomy, voluntary tail shedding, but lack the ability to regenerate lost tails. The cause of this regenerative failure remains poorly understood. The purpose of this research is to assess whether the inability of crested geckos to regenerate lost tails is associated with failure to form a blastema following tail autotomy. To determine whether crested geckos form a blastema following tail amputation, cell proliferation in amputated tails of crested geckos is compared with regenerating green anoles (Anolis carolinensis) using Ki67 and PCNA immunostaining. Ki67 and PCNA positive cells are quantified to assess blastema formation. Preliminary immunostaining optimization is being conducted using antibody dilutions of 1:100, 1:500, and 1:1000 to determine optimal staining conditions. Data collection and analysis are currently underway. Preliminary immunostaining identified 1:500 as the current optimal antibody dilution for Ki67 and PCNA detection, producing strong specific nuclear staining with minimal background compared with the 1:100 and 1:1000 dilutions. Manual quantification was selected as the current approach for assessing cell proliferation based on staining quality and limitations with automated detection. This dilution and method will continue to be evaluated for subsequent analysis of proliferation cells during blastema formation. Ongoing analyses will determine whether the absence of blastema formation contributes to regenerative failure in crested geckos. This study may identify mechanisms required for successful epimorphic regeneration and advance understanding of why some species, like humans and crested geckos, lack this regenerative capacity.