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PubMed · 3746883

Urinary immunoglobulin G: a routine and highly sensitive technique based on competitive binding.

U Di Mario·S Morano·M Mancuso·P Pietravalle·A Napoli·S Gambardella·D Andreani
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Abstract

The evaluation of both small amounts of urinary immunoglobulins and the albumin/immunoglobulin ratio are important indices during the early stages of diabetic nephropathy. For this reason there is at present a need for highly-sensitive and specific routine tests for urinary immunoglobulins. A technique has been designed based on the competition between radiolabelled immunoglobulin G and immunoglobulins in the urine to be tested in binding to an anti-immunoglobulin antibody in solid phase. The immunoglobulin fraction of a rabbit anti-human immunoglobulin antiserum in a basic Ca-carbonate buffer is left to coat highly adsorbent polystyrene microtitre tubes. After the antibody-coated tubes have been saturated with gelatine, a 1/5 dilution of the urine to be tested and an equal volume of purified and radiolabelled human immunoglobulin G are left to incubate and are then added to the antibody-coated tubes. After incubation and repeated washings, radioactivity is counted. This technique has the characteristics of a routine assay for the accurate detection of immunoglobulin G in the urine. It requires only a few microliters of urine, takes only 3 hr to complete (after having coated the tubes) and detects about 120 ng of immunoglobulin G/ml, well below what is needed to assess physiological or pathological values.

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Binding, CompetitiveDiabetes MellitusDiabetic NephropathiesDose-Response Relationship, ImmunologicHumansImmunoglobulin GJournal ArticleResearch Support, Non-U.S. Gov't

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U Di Mario, S Morano, M Mancuso, P Pietravalle, A Napoli, S Gambardella, D Andreani. 1986. Urinary immunoglobulin G: a routine and highly sensitive technique based on competitive binding.. https://pubmed.ncbi.nlm.nih.gov/3746883/

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