Effects of TGF-βs on the growth, collagen synthesis and collagen lattice contraction of human dental pulp fibroblasts in vitro

Transforming growth factor-beta (TGF-beta) is important in regulating the repair and regeneration of damaged dental pulp. For further elucidating the roles of different isoforms of TGF-beta in the heating and inflammatory processes of human dental pulp, we found that TGF-beta l, TGF-beta 2 and TGF-beta 3 inhibited the growth of two human dental pulp cell strains in vitro by 19-29, 18-25 and 23-26%, respectively, at a concentration of 0.5 ng/ml. TGF-beta also differentialty stimulated the collagen synthesis of pulp cells. Collagen synthesis increased by 1 ng/ml of TGF-beta 1 and TGF-P2 by 42 and 51%, respectively. TGF-beta 3 (0.1-1 ng/ml) lacked of stimulatory effect on collagen synthesis of pulp cells. Pulp cells have the intrinsic capacity to contract cottagen lattice, leading to decreasing of Lattice diameter. An 8 h exposure to TGF-beta 1 and TGF-beta 2 enhanced the pulp cett-populated collagen lattice contraction at concentrations ranging from 0.2 to 3 ng/ml. At similar concentrations, TGF-beta 3 Lacked of this stimutatory effect. When cottagen Lattice were detached after 24 h of exposure, TGF-beta 1 and TGF-beta 2 (0.6-3 ng/ml) induced the pulp cells-populated cottagen lattice contraction within 4-8 h of get detachment. These results indicate that TGF-beta-induced collagen lattice contraction is a late cellular event. These in vitro results indicate that effects of TGF-beta isoforms on the growth, collagen synthesis and collagen lattice contraction of pulp cells may play crucial roles in the pathobiological processes of dental pulp. (c) 2004 Elsevier Ltd. All rights reserved.