Transplantation of human pulpal and gingival fibroblasts attached to synthetic scaffolds

Autologous tissue grafting for the restoration of oral tissues is limited by several factors, including the availability of sufficient donor tissue. One solution to this problem may be to develop substitute tissue grafts by attaching disaggregated autologous cells propagated in vitro to scaffolds composed of natural or synthetic polymers. We have earlier demonstrated that human dental pulp and gingival fibroblasts (HPF, HGF) adhere to non-woven polyglycolic acid (PGA) scaffolds, proliferate and produce extracellular matrix in vitro. We now report that such HPF and HGF adhered to PGA scaffolds survive when implanted into subcutaneous sites in immune-compromised mice. The transplanted cells synthesize and secrete type I collagen, cellular fibronectin and may express genes implicated in transducing bone morphogenetic protein (BMP) signals. Messenger RNA for BMP-2, -4, -7 (OP-l), the BMP type I receptors Act RI, BMPR-1A and 1B, the type II receptor BMPR-II, and type I collagen were detected by reverse transcription-polymerase chain reaction (RT-PCR). These data revealed that three adult human dental pulp and gingival cell populations, each from individual donors, attached to PGA scaffolds and cultured for 24 h in vitro, survive implantation and express genes indicative of a capacity to produce extracellular matrix. The implanted cells may also express genes associated with responsiveness to BMP-mediated tissue inductive signals.