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The amelogenins are secreted by the ameloblast cells of developing teeth; they constitute about 90 % of the enamel matrix proteins and play an important role in enamel biomineralization. Recent evidence suggests that amelogenin may also be involved in the regen-eration of the periodontal tissues and that diVerent isoforms may have cell-signalling eVects. During enamel development and miner-alization, the amelogenins are lost from the tissue due to sequential degradation by speciWc proteases, making isolation of substantial puriWed quantities of full-length amelogenin challenging. The aim of the present study was to express and characterize a recombinant human amelogenin protein in the eukaryotic baculovirus system in quantities suYcient for structural and functional studies. Human cDNA coding for a 175 amino acid amelogenin protein was subcloned into the pFastBac HTb vector (Invitrogen), this system adds a hexa-histidine tag and an rTEV protease cleavage site to the amino terminus of the expressed protein, enabling eVective one-step puriWcation by Ni2+–NTA aYnity chromatography. The recombinant protein was expressed in Spodoptera frugiperda (Sf9) insect cells and the yield of puriWed his-tagged human amelogenin (rHAM+) was up to 10 mg/L culture. Recombinant human amelogenin (rHAM+) was characterized by SDS–PAGE, Western blot, ESI-TOF spectrometry, peptide mapping, and MS/MS sequencing. Pro-duction of signiWcant amounts of pure, full-length amelogenin opened up the possibility to investigate novel functions of amelogenin. Our recent in vivo regeneration studies reveal that the rHAM+ alone could bring about regeneration of the periodontal tissues; cementum, periodontal ligament, and bone