Solid phase radioimmunoassays for human C-reactive protein

• Published in: Clinica chimica acta Vol. 117; no. 1; p. 13
• Main Authors: Shine, B, de Beer, F C, Pepys, M B
• Format: Journal Article
• Language: English
• Published: Netherlands 25-11-1981
• Subjects: Adolescent; Adult; C-Reactive Protein - analysis; Female; Humans; Male; Middle Aged; Radioimmunoassay - methods
• ISSN: 0009-8981
• DOI: 10.1016/0009-8981(81)90005-X

Two new, rapid and sensitive radioimmunoassays for human C-reactive protein (CRP) have been established using antiserum coupled to magnetizable cellulose particles, which facilitate phase separation. A single antibody method, using solid phase anti-CRP, provides a sensitivity of 50 microgram/l with a 1-h incubation time and intra- and inter-assay coefficients of variation of 10%. A double antibody method, using fluid phase rabbit anti-CRP serum and solid phase sheep anti-rabbit IgG serum, provides a sensitivity of 3 microgram/l with an overnight incubation and intra- and inter-assay coefficients of variation of 10%. Among 468 sera from normal adult volunteer blood donors the median CRP concentration was 800 microgram/l, interquartile range 340-1700 microgram/l and range 70-29,000 microgram/l. Ninety percent of samples contained less than 3 mg/l and 99% less than 10 mg/l. Low levels (14-650 microgram/l) of CRP were detected both in amniotic fluids and in cerebrospinal fluids.