Circulating beta(1) Adrenergic Autoantibodies from Patients with Chronic Periodontitis Interact with Gingival Fibroblasts.

Objectives: To demonstrate the presence of circulating autoantibodies (Abs) from patients with chronic periodontitis (CP) that interacted with human gingival fibroblast membranes activating beta(1) adrenoceptors (beta(1)-AR).

Methods: Sera and purified IgG from 25 patients with CP and 20 age-matched healthy subjects were studied by flow cytometry, ELISA and DNA synthesis. Human gingival fibroblast membranes and/or synthetic peptides with amino acid sequences identical to human beta(1)-AR were used as antigens.

Results: By flow cytometry and ELISA procedures, we proved that the serum-purified IgG fraction from patients with CP reacted with the fibroblast surface and to the beta(1) synthetic peptide. The corresponding affinity-purified anti-beta(1) peptide Abs displayed agonist-like activity associated with specific receptor activation, inhibiting the DNA synthesis of human gingival fibroblasts.

Conclusions: This study demonstrates that beta(1)-AR autoantibodies are elevated in patients with CP. These autoantibodies were targeted to the fibroblasts, and specifically to the beta(1)-AR, and has receptor-like activity inhibiting DNA synthesis.