Tsai SL, Baselga-Garriga C, Melton DA. 2019. Blastemal progenitors modulate immune signaling during early limb regeneration. Development (Cambridge, England). 146(1). Pubmed: 30602532


Blastema formation, a hallmark of limb regeneration, requires proliferation and migration of progenitors to the amputation plane. Although blastema formation has been well described, the transcriptional programs that drive blastemal progenitors remain unknown. We transcriptionally profiled dividing and non-dividing cells in regenerating stump tissues, as well as the wound epidermis, during early axolotl limb regeneration. Our analysis revealed unique transcriptional signatures of early dividing cells and, unexpectedly, repression of several core developmental signaling pathways in early regenerating stump tissues. We further identify an immunomodulatory role for blastemal progenitors through interleukin 8 (IL-8), a highly expressed cytokine in subpopulations of early blastemal progenitors. Ectopic expression in non-regenerating limbs induced myeloid cell recruitment, while IL-8 knockdown resulted in defective myeloid cell retention during late wound healing, delaying regeneration. Furthermore, the receptor was expressed in myeloid cells, and inhibition of CXCR-1/2 signaling during early stages of limb regeneration prevented regeneration. Altogether, our findings suggest that blastemal progenitors are active early mediators of immune support, and identify CXCR-1/2 signaling as an important immunomodulatory pathway during the initiation of regeneration.
© 2019. Published by The Company of Biologists Ltd.

Related Faculty

Photo of Doug Melton

Doug Melton is pursuing a cure for type 1 diabetes. His lab studies the developmental biology of the pancreas, using that information to grow and develop pancreatic cells (islets of Langerhans). In parallel, they investigate ways to protect beta cells from autoimmune attack.

Search Menu