Expression of neural crest linage marker in osteogenic tissue of the armadillo dasypus hybridus (Xenarthra, cingulata, dasypodidae) fetus dermis.

KRMPOTIC, C.M.; NISHIDA, F.; GALLIARI, F.C.; STROBL MAZZULLA, P.H.; CARLINI, A.A.F.; BARBEITO, C.G.

Buenos Aires

Jornada; XVIII Jornadas Anuales Multidisciplinarias de la Sociedad Argentina de Biología; 2016

Sociedad Argentina de Biología

Neural crest cellsgive rise to various cell populations in the adult vertebrate including facialbones. In some reptiles, such as turtles and crocodiles, neural crest isinvolved in the origin of the osteoderms (dermis ossifications). In modernmammals, osteoderms are only present in the Dasypodidae (armadillos, tatus,etc) skin. The osteoderm formation is a complex process including bothmetaplastic and intra-membranosous ossification mechanisms. At present thereare not studies about a possible neural crest origin of the of the Dasypodidaeosteordems. In this work we focus on Dasypus hybridus,a Dasypodidae species, toassess the presence of a neural crest marker (the HNK-1 epitope), which hasbeen previously found in the osteoderm precursor tissue of reptiles. Samples ofdorsal and ventral skin of fetus and neonates of D. hybridus were processed forimmunohistochemistry using a HNK-1 antiobody. The ventral skin mesenchymal orconnective tissues were negative, but in the dorsal region of a fetus (totallength 90.8 mm) positive cells were found in the subepidermal region of theundifferentiated dermis. Positive cells were absent in the region between theepidermal scales, where the osteoderms never develops. These results are thefirst evidence of a potential neural crest origin of poscranial ossificationsin mammals. Further works are in progress, using others neural crest markersand alternative designs to demonstrate negative melanocyte lineages in thesecells.