ANTI-CENP-B RESPONSE IN SERA OF URANIUM MINERS EXPOSED TO QUARTZ DUSTAND PATIENTS WITH POSSIBLE DEVELOPMENT OF SYSTEMIC-SCLEROSIS (SCLERODERMA)

Objective. To look for anti-CENP-B antibodies and their diagnostic rel evance in patients negative and positive for anticentromere antibodies (ACA) with different risk for the development of systemic sclerosis ( SSc), including uranium miners exposed to quartz dust. Methods. We stu died sera of 107 patients with SSc, 121 patients with possible SSc, 20 2 uranium miners heavily exposed to quartz dust, 14 patients with vibr ation induced white fingers, and 240 control patients. Subjects were s creened for ACA by indirect immunofluorescence on HEp-2 cells (IIF-ACA ) and then for anti-CENP-B autoantibodies by an ELISA using eukaryotic ally expressed human full length recombinant CENP-B protein. Results. All IIF-ACA positive sera of ''idiopathic'' SSc (N = 19), ''idiopathic possible'' SSc (N = 6) and other patients (N = 11), and 17 of 19 IIF- ACA positive sera of miners exposed to silica with (N = 13) and withou t (N = 6) symptoms of SSc reacted with CENP-B in this assay, Of the 62 2 IIF-ACA negative sera, 28 were found positive for anti-CENP-B. There was a significant increase of the prevalence of anti-CENP-B antibodie s in IIF-ACA negative patients with possible SSc (11 of 109) and in mi ners exposed to silica (11 of 196) compared to a group of men older th an 60 years with diseases or symptoms not related to SSc (1 of 138). C onclusion. (1) CENP-B is also the major target of the IIF-ACA response in diseases other than scleroderma and in the risk group of miners ex posed to quartz dust, (2) Anti-CENP-B antibodies can be found in IIF-A CA-negative sera, particularly in those at risk for SSc. (3) The detec tion of anti-CENP-B antibodies in miners exposed to quartz dust may in dicate a high risk group for developing SSc and reveals possibilities for the study of early pathogenetic changes as well as exogenic and en dogenic factors involved in the development of this disease.