Abstract
Molecular mechanism (s) involved in adhesive interactions between T lymphocytes and human gingival fibroblasts (HGF) were examined. Both human peripheral blood T lymphocytes and T cell leukemia line, Molt-4 demonstrated significant binding ability to HGF only when the cells were activated with phorbol 12-myristate 13-acetate (PMA) . In order to reveal the molecule (s) responsible for the adherence, a panel of monoclonal antibodies (mAbs) was prepared against PMA-activated Molt-4 and mAb, 4-145 was finally entablished on the basis of its ability to block the adherence of activated Molt -4 to HGF. Biochemical and functional analysis revealed that 4-145 recognizes an epitope on VLAβ1 chain. Furthermore, blocking experiments utilizing mAbs specific for VLAα chains demonstrated that VLA-4 plays an important role for mediating the adhesion of activated T lymphocytes to HGF.
Results demonstrated in this study suggest that VLA integrins play critical roles not only in binding to activated endothelial cells in inflammatory sites but also in retention of activated T lymphocytes in inflamed periodontal lesions by mediating the adhesive interaction between T lymphocytes and HGF.
