CLONALLY EXPANDED LYMPHOCYTES IN THE MINOR SALIVARY-GLANDS OF SJOGRENS-SYNDROME PATIENTS WITHOUT LYMPHOPROLIFERATIVE DISEASE

Objective. To determine whether clonally expanded B cells are present in the early infiltrates of minor labial salivary glands (LSG) of Sjog ren's syndrome (SS) patients. Methods. Available paraffin-embedded LSG biopsies from 14 patients with primary SS were studied. DNA from LSG tissue was amplified by a polymerase chain reaction directed toward re arranged immunoglobulin gene DNA. Results. All LSG specimens showed ol igoclonal or monoclonal B cell expansion. In one patient with plasma c ell neoplasm, tumor and LSG specimens obtained at the same operation d isplayed different immunoglobulin gene rearrangements. Conclusion. Clo nal expansion is characteristic of primary SS, and it is uniformly fou nd in the early LSG infiltrates of patients who do not experience furt her progression to pseudolymphoma or lymphoma (mean followup 4.1 years after biopsy). This feature, together with the clonal discordance bet ween the LSG and the B cell neoplasm found in one patient, suggests th at additional steps are critical for the progression to malignancy.