Effects of PHEX antibodies on the development of mouse tooth germ

AIM:To investigate the effects of PHEX antibodies and possible roles of PHEX on the development of mouse tooth germ.METHODS:0.1mg/kg(group A)and 0.5mg/kg(group B)concentration of the PHEX antibody and 0.1M PBS(control group N)were injected into E17 pregnant rat through the tail vein.Samples of different stages,including early bell stage(E18),the late bell stage(P1)and dental hard tissue formation and mineralization stage(P3)were prepared and stained with Mallory's trichrome and immunohistochemical staining.RESULTS:Mallory trichrome staining results showed that there was no significant difference in the development of enamel in above three groups.No significant differences were also seen in the differentiation of odontoblasts and formation of dentin in group A and N.However,differentiation of odontoblasts and formation of dentin were significantly delayed and suppressed in group B.Expression of PHEX protein in ameloblasts of E18,P1,P3 were strongly positive in all three groups.Strong positive signals were also found in odontoblasts in P1,P3 of group A and N.But in the B group,weak positive PHEX signals were detected in dental papilla cells adjacent to the basement menbrane in P1 and in odontoblasts in P3.CONCLUSION:0.5mg/kg concentration of PHEX antibody could significantly inhibited the differentiation and PHEX expression in odontoblasts,and thus inhibit the formation of dentin.PHEX antibodies could not effect the differentiation of ameloblasts and mineralization of enamel.