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PubMed · 7720251

Automated homogeneous liposome-based assay system for total complement activity.

S Yamamoto·K Kubotsu·M Kida·K Kondo·S Matsuura·S Uchiyama·O Yonekawa·T Kanno
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Abstract

We developed an automated homogeneous immunoassay, based on immune lysis of dinitrophenyl (DNP)-labeled liposomes, for measuring total complement activity. Liposome lysis caused by complement activity was detected spectrophotometrically from entrapped glucose-6-phosphate dehydrogenase activity. Complement activity in human sera was quantified by comparison with a calibration curve. For ease of application to fully automated routine clinical analyzers, we adopted a two-reagent system, one reagent containing a homogeneous population of small DNP-labeled liposomes and one containing antibody/substrate. This system required calibration only once a week. Within-run and between-run CVs were 0.4-1.3% (n = 10) and 1.8-4.7% (n = 10), respectively. Serum results were linear upon dilution (with saline) over a twofold range. Bilirubin, hemoglobin, Intrafat, and serum proteins such as rheumatoid factor, M protein, IgG, and IgA did not affect the assay results. The results (y) correlated well with those from a hemolytic complement activity test (x): y = 1.05x - 1.14, r = 0.92, on 66 samples in the range < 10- > 50 kU/L. This method should therefore be of great use for the determination of complement activity.

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AdolescentAdultAnimalsAutoanalysisCalibrationComplement System ProteinsDinitrobenzenesFemaleGlucosephosphate DehydrogenaseHumansIndicators and ReagentsKineticsLiposomesMaleMiddle AgedQuality ControlRatsReference ValuesSpectrophotometryJournal Article

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S Yamamoto, K Kubotsu, M Kida, K Kondo, S Matsuura, S Uchiyama, O Yonekawa, T Kanno. 1995. Automated homogeneous liposome-based assay system for total complement activity.. https://pubmed.ncbi.nlm.nih.gov/7720251/

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