Quantitative determination of immunoglobulins in the hemagglutination inhibition reaction. I. a method of expressing the results based on a comparison with a standard and using a logarithmic scale
Levenson, V.I.; Subbotina, I.L.
Zhurnal Mikrobiologii Epidemiologii i Immunobiologii 10: 56-62
1979
ISSN/ISBN: 0372-9311 PMID: 506601 Document Number: 145908
The sources of errors in the quantitative determination of immunoglobulins in the passive hemagglutination inhibition test are considered. The influence of some factors (the quality of erythrocyte diagnostic reagents, the non-standard working dose of the antiserum) can be reduced if in each test the material under study is compared with a known preparation having known serological activity (standard preparation). A suggestion is made on the advisability of expressing the results of the test in the logarithmic (log2) scale of serological activity units (SAU), where the activity of 100 IU/ml is considered to be 10 units. The serological activity of the standard preparation used in this research was determined against a set of Hyland reference sera. The average level and varibility of immunoglobulin content in the sera of healthy adults were determined with the use of 104 serum samples. The average level was 10.2 +/- 0.1 SAU for IgG, 10,4 +/- 0.1 SAU for IgA and 9.6 +/- 0.1 SAU for IgM, with sigma for all immunoglobulins being about 1.0. The reproducibility of the passive hemagglutination inhibition test was satisfactory; the variability of the results after repeated tests seldom exceeded 1 SAU.