Analysis of developmental potentials of dental pulp in vitro using GFP transgenes

Structured Abstract Authors –  Balic A, Mina M Background –  In recent years there has been increasing progress in identifying stem cells from adult tissues and their potential application for tooth replacement/regeneration. Our previous in vivo studies show that pOBCol3.6GFP and pOBCol2.3GFP transgenic animals provide a unique model to gain insight into progenitor/stem cells in the dental pulp capable of giving rise to odontoblasts. Objectives –  To characterize the behavior of dental pulp cells derived from pOBCol3.6GFP animals in vitro. Experimental design –  Primary cultures were established from the coronal portions of the pulps isolated first molars from 5-day-old pOBCol3.6GFP heterozygous mice and grown for 21 days. In these cultures proliferation, clonogenic capacity, activation of 3.6-GFP and mineralization were examined. Results –  Our observations show that dental pulp cells derived from 3.6-GFP contain a population of proliferative, clonogenic cells with the ability to mineralize. We also show the stage specific activation/upregulation of 3.6-GFP in primary cultures derived from dental pulp. In these cultures, expression of Col1a1-3.6-GFP occurs prior to the appearance of mineralized nodules and is unregulated in mineralized nodules. Conclusions –  Col1a1-GFP transgenes appear to fulfill many of the requirements of a marker gene for cell lineage studies in intact tooth and primary cultures derived from dental pulp.