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PubMed · 6414736

DNA interference with radioimmunoassay procedures.

N Matsuo·S S Koide
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Abstract

A bacterial factor preventing precipitation of immune complexes was purified from a culture of Streptococcus faecalis (AK strain) by gel filtration on Sephadex G-100 and Bio-Gel A-150m columns. The factor was identified as DNA on the basis of its ultraviolet absorption maximum at 260 nm, hydrolysis by deoxyribonuclease, Mr exceeding 1.5 X 10(8), and positive reaction with diphenylamine. DNA interferes with the immunoassay by preventing precipitation of immune complexes. Only double-stranded DNA and polynucleotides showed this property. Evidently, double-stranded DNA will give false-positive interference with the usual RIA procedures.

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Antigen-Antibody ComplexChorionic GonadotropinChromatography, GelDNA, BacterialEnterococcus faecalisFalse Positive ReactionsRadioimmunoassayJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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N Matsuo, S S Koide. 1983. DNA interference with radioimmunoassay procedures.. https://pubmed.ncbi.nlm.nih.gov/6414736/

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