The heterogeneity of autoantibody specificities occurring in sera from patients with systemic sclerosis (SSc) raised the necessity of developing various methodologies for their detection. A cohort of 150 SSc patients were selected and tested by Indirect Immunofluorescence (IIF), Counterimmunoelectrophoresis (CIE), Immunoblot (IB) using various extracts as antigenic source and RNA precipitation. By preparing a nuclear (IB-nuclear) and a metaphase chromosomal-enriched extract (IB-MC-pellet) from HeLa cells as well as a nucleolar (IB-nucleolar) and a histone (IB-histone) extract from rat liver nuclei, we assessed their sensitivity and specificity for anti-Topo I, anti-U3RNP, anti-H1, anti-snRNPs antibodies and ACA. IB-nuclear revealed the highest frequency of anti-Topo I antibodies, while CIE, IB-nucleolar and IB-MC-pellet, when compared to IB-nuclear showed a sensitivity of 89%, 87% and 95%, respectively. IB-MC-pellet was unique for ACA recognition, while IB-nucleolar and IB-MC-pellet showed excellent sensitivity for anti-U3RNP and anti-H1 antibody detection. We conclude that IB-nuclear is a highly sensitive system for anti-Topo I antibodies determination, but CIE reveals a good sensitivity to be used as a first screening test. IB-nucleolar or IB-MC-pellet are important techniques to detect the variety of antibodies to nucleolus and chromatin-related constituents. A novel specificity against a 28kD nucleolar protein, non-associated with RNAs is also presented.