Production of monoclonal antibodies against murine dental papilla

The mesenchymal component of the embryonic tooth, the dental papilla, shows unique cellular behavior. Only the dental papilla cells are capable of differentiating into odontoblasts. The dental papilla also directs the morphogenesis of the tooth. Our aim is to develop suitable markers for further studies on the molecular mechanisms behind the determination and differentiation of the dental mesenchymal cells. We have produced monoclonal antibodies against this embryonal cell population. Altogether 1114 enzymatically separated mesenchymes from dissected molar tooth germs of 17-day-old mouse embryos were fixed in paraformaldehyde (PFA) and sonicated in saline. A rat was immunized and hybridomas were produced by standard methods. The supernatants were screened by immunohistology, using both frozen sections and sections of PFA-fixed paraffin-embedded mouse molar teeth. Altogether, 19 wells produced antibodies reacting with dental tissues. One monoclonal antibody recognizes a 67,000 dalton intracellular antigen enriched in secretory odontoblasts and ameloblasts. The antigen is also found in osteoblasts and chondrocytes in the developing jaw, and in some cultured murine cells. The method described here appears to be successful for generating and screening monoclonal antibodies against the dental papilla.