Evaluation of the single radial haemolysis (SRH) technique for rubella antibody measurement.

Abstract

SUMMARY Sera from 1258 individuals have been tested by four laboratories for rubella antibody by both the haemagglutination-inhibition and single radial haemolysis techniques. There was good agreement between the results obtained by the two methods. Although sheep red blood cells were used in the single radial haemolysis plates, no problems were encountered with sera from patients with infectious mononucleosis.The single radial haemolysis technique was found to be simple, convenient, and reliable, and suited to the rapid screening of large numbers of sera to assess susceptibility to rubella in the context of a vaccination campaign. However, since the technique does not detect anti-rubella IgM, it should not be used as the only test to investigate suspected recent infection.The haemagglutination-inhibition (HAI) test is at present the one most widely used for detecting antibodies to rubella virus. However, this test is laborious and time-consuming to perform: sera must be pretreated to remove non-specific inhibitors; they may require absorption to remove red cell agglutinins; and they must be individually diluted. In addition, the test involves a large number of variables which can give rise to poor reproducibility (Gust et al., 1973).The single radial haemolysis (SRH) technique was first developed to detect and measure influenza antibody (Russell et al., 1975;Schild et al., 1975) and, because of its simplicity, accuracy, and reproducibility, has now been used for detecting antibodies against rubella virus.We here report an evaluation of the SRH technique as a replacement for the HAI test in the routine screening of large numbers of sera for rubella antibody. Sera were examined undiluted. A 10-,ul volume of test serum was added to each well and allowed to diffuse through the gel overnight at 40C. The gels were then flooded with a 1:10 dilution of guinea-pig complement (Wellcome Reagents Ltd) and incubated in a humidified atmosphere at 370C for three hours.Plates were examined immediately or fixed in 10% formol saline. The diameters of the zones of haemolysis were then measured, and the corresponding annulus areas were calculated (total area minus area of well).Since some human sera contain sufficient antisheep red blood cell antibody to produce a very small zone of lysis, sera were defined as SRHpositive only if the area of lysis exceeded 5 mm2, that is, the lysis extended more than 0-5 mm from the edge of the well.

A comparison of three tests for rubella antibody screening.

“…They were prepared and used according to Russell et al (1978). In the laboratory, plates were stored at 40C and used within 14 days of receipt.…”

“…It has been suggested that single radial haemolysis (SRH) and enzyme-linked immunosorbent assay (ELISA) would offer considerable advantages (Voller and Bidwell, 1975;Russell et al, 1978).…”

Validation of Single Radial Haemolysis assay: A reliable method to measure antibodies against influenza viruses

“…The SRH assay is a technique used to detect antibodies not only against influenza A and B viruses but also against numerous other viruses such as Rubella, Parainfluenza virus, Dengue and Japanese Encephalitis viruses (Schild et al, 1975;Chan et al, 1985;Russell et al, 1978).…”

Altered hemolysis in single radial hemolysis from a single serum sample as an indicator of recent primary rubella virus infection

“…For the latter purpose, the SRH test has the limitation that IgM or IgA antibodies are not detected [Strannegard et al, 1975;Russell et al, 1978;VGnanen and Vaheri, 1979;Kurtz et al, 19801. Thus, paired sera are required.…”