Objective: To analyze Ro and La autoantibody levels in the periphery and production in the target organ in patients with Sjögren's syndrome.
Methods: The autoantibody production against the Ro and La proteins was investigated in 12 patients with Sjögren's syndrome. ELISA with recombinant antigens was used to determine levels in sera. The distribution of the antibody-producing plasma cells in the target organ was studied by immunohistochemistry using biotinylated antigens.
Results: All investigated patients with Sjögren's syndrome had detectable levels of Ro and La antibodies in sera, while local antibody-production in the salivary glands was restricted to patients with high antibody levels. The autoantibody-producing cells were identified at the periphery of the infiltrates and in interstitial spaces.
Conclusions: The chronic inflammation of the salivary glands in Sjögren's syndrome may be a self-sustaining process promoting autoantibody production in the target organ, possibly contributing to increased serum levels of autoantibodies.