[The high frequency of spontaneous micronuclei observed in lymphocytes of systemic sclerosis patients: preliminary results].

OBJECTIVE Aim of the study is to assess the presence of spontaneous chromosome damage in patients affected by limited (lSSc) or diffuse (dSSc) Systemic Slerosis, using the micronucleus (MN) assay. METHODS We evaluated MN frequency in cultured peripheral lymphocytes of 18 SSc and in a group of 20 healthy controls. Patients were also classified as ACA+, Scl70+, FAN+ according to the presence of the specific anti-nuclear antibodies. We also explored the hypothesis that the extent of cytogenetic alteration might be related to the severity of the pathological condition and/or to the immunological profile. RESULTS Compared to controls, the patient group as a whole showed significantly higher MN frequencies (10.8+/-4.5 vs. 27.8+/-13.7, p<0.001). No correlation was found between spontaneous chromosome damage and severity of the disease, being MN frequency 33.1+/-17.0 and 19.8+/-2.7 in lSSc and dSSc, respectively. Interestingly, ACA+ subjects displayed the highest MN frequency (36.9+/-15.0), as compared to patients with different antibody pattern (Scl70+, FAN+; 19.7+/-8.2). CONCLUSIONS Our results confirm the presence of chromosomal damage in circulating lymphocytes of SSc patients and would suggest a key role of antibodies to the centromere in determining the observed cytogenetic anomalies.