Transforming growth factor-beta isoform expression in mature human healthyand carious molar teeth

Transforming growth factor (TGF)-beta isoforms have been implicated in cell ular signalling during tooth development and repair, but little is known of their cellular localisation or distribution within the dental tissues in t he mature tooth. This study investigated the presence of TGF-beta 1, beta 2 and beta 3 isoforms in tissues of sound and carious human molar teeth, to understand better the expression of TGF-beta s during health and disease. I n healthy tissues, odontoblasts, cells of the cell rich layer, pulpal fibro blasts and endothelial cells were stained to varying degrees for all isofor ms, with TGF-beta 3 showing the greatest intensity and TGF-beta 1 the weake st intensity. Similar patterns of staining were observed in carious teeth; however, TGF-beta 1 showed significantly increased staining intensity withi n odontoblasts and pulpal cells of carious teeth (p < 0.001). Biochemical a nalysis showed greater amounts of TGF-beta 1 in tertiary dentine than in pr imary dentine samples. The expression of TGF-beta s in odontoblasts and the increased presence of TGF-beta 1 in tertiary dentine suggest that these is oforms may be important in odontoblast behaviour and the modulation of the tissue response to injury.