A sensitive assay for serum acid soluble proteins with Coomassie brilliant blue G 250 and its application for autoimmune diseases
Oshima, I.; Kohama, T.; Kodaira, T.
Tokushima Journal of Experimental Medicine 34(1-2): 23-27
1987
ISSN/ISBN: 0040-8875 PMID: 2454516 Document Number: 287536
A sensitive method was developed for measurement of serum acid-soluble proteins (ASP) in normal subjects and patients with autoimmune diseases. ASP were extracted from human serum with perchloric acid 0.6 mol/litre and measured with Coomassie Brilliant Blue G 250. The lower limit of detection of serum ASP was 0.01 g/litre by this method. The intra- and interassay coefficients of variation at ASP concentration of 0.98 to 3.51 g/litre were 1.9 and 5.5%, respectively. The recovery of ASP from serum when present at 0.12 to 10.0 g/litre was 89.5 to 104.6%. The concentration of serum ASP in 206 normal subjects 18 to 70 years old was 1.05 +or- 0.17 g/litre (mean +or- s.d.). Their concentration was significantly increased in patients with systemic autoimmune diseases, but not in patients with organ-specific autoimmune diseases. The results indicate that routine measurement of serum ASP is useful in determining the pathogenesis of autoimmune diseases.