RT Journal Article SR Electronic T1 Detection of maternal-fetal microchimerism in the inflammatory lesions of patients with Sjögren's syndrome JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 1041 OP 1046 DO 10.1136/ard.61.12.1041 VO 61 IS 12 A1 M Kuroki A1 A Okayama A1 S Nakamura A1 T Sasaki A1 K Murai A1 R Shiba A1 M Shinohara A1 H Tsubouchi YR 2002 UL http://ard.bmj.com/content/61/12/1041.abstract AB Background: A possible relation between maternal-fetal microchimerism and autoimmune diseases with some similarities to chronic graft versus host disease (cGVHD) has been reported. Objective: To investigate whether cells with male DNA exist in female patients with Sjögren's syndrome (SS) as SS has clinical features similar to those of cGVHD. Methods: DNA was extracted from 27 samples of peripheral blood mononuclear cells (PBMC), 42 biopsy samples of labial salivary glands (LSG), and nine samples of bronchoalveolar lavage fluid (BALF) cells from 56 female patients with SS. The presence of male DNA was determined by nested polymerase chain reaction (PCR) and by fluorescence in situ hybridisation (FISH). Results: Among 56 female patients with SS, 42 patients had at least one male child. Among those 42 patients, none of the 22 PBMC but 10/28 (36%) LSG samples tested positive by PCR for the Y chromosome-specific sequence (p=0.0013). The Y chromosome-specific sequence was not detected in the samples of LSG in 10 patients without SS. In the BALF samples 2/9 (22%) patients with SS tested positive by PCR. Cells containing the Y chromosome were shown to exist in all the LSG specimens from three female patients with SS by FISH. Conclusions: Maternal-fetal microchimerism was shown for the first time to exist in the salivary glands and lungs of female patients with SS in this study. The presence of non-host cells in the inflammatory lesions but not in the peripheral blood suggests a possible role for maternal-fetal microchimerism in the pathogenesis of SS.