Single Radial Haemolysis Research Articles

Correlation between Rate of Infection and Preexisting Titer of Serum Antibody as Determined by Single Radial Hemolysis during an Epidemic of Influenza A/Victoria/3/75

During an outbreak of infection with wild-type influenza A/Victoria/3/75 virus, a correlation was established between the rate of infection and the preepidemic titer of serum antibody to that virus as measured by the single radial hemolysis technique. Titers of antibody determined by the hemagglutination inhibition method as well as by the single radial hemolysis technique were directly correlated with the rate of infection. By use of the single radial hemolysis technique, the 50% protective titer of antibody was calculated for a population of recipients of live influenza A/Victoria/3/75 virus vaccine.

A single radial haemolysis technique for the measurement of antibody to Mycoplasma bovis in bovine sera

A single radial haemolysis in gel technique is described for assaying antibody to Mycoplasma bovis (M agalactiae subsp bovis) in bovine sera. The test, which should be particularly useful for screening large numbers of serum samples, is sensitive, simple to perform and highly reproducible.

Quantitation of Antibody to Non-Hemagglutinating Viruses by Single Radial Hemolysis: Serological Test for Human Coronaviruses

A single radial hemolysis test was developed for quantitation of specific antibody to non-hemagglutinating viruses. With the human coronaviruses as models, this test utilizes the binding properties of the chromic cation to attach viruses to glutaraldehyde-treated sheep erythrocytes. The most satisfactory system consisted of stabilizing washed sheep erythrocytes with 0.0073% glutaraldehyde for 15 min at 23 degrees C, binding a high concentration of virus to a 25% erythrocyte suspension with 0.0016% chromic chloride for 20 min at 23 degrees C, stopping the reaction with phosphate-saline, and finally mixing the treated, rewashed cells with complement and agarose at 45 degrees C to prepare a slide gel. The gel mix, which was dispensed in plastic plates (23 by 73 mm) in 3-ml volumes, consisted of 1% agarose, 0.1% sodium azide, 5% reconstituted complement, and 0.82% treated cells. Wells 2 mm in diameter were loaded with 5 mul of antiserum, incubated for 18 h at 4 degrees C for diffusion of antiserum and fixation of complement, and then incubated for 8 to 24 h at 37 degrees C for development of hemolysis zones. The diameter of a zone was linearly related to antibody concentration, as determined by conventional serological tests. This single radial hemolysis test was applicable to human and animal coronaviruses and to selected serotypes of the adenovirus, picornavirus, rhabdovirus, and rotavirus groups.

Evaluation of the Single Radial Hemolysis Test for Measuring Hemagglutinin- and Neuraminidase-Specific Antibodies to H3N2 Influenza Strains and Antibodies to Influenza B

Antibodies to the H3 hemagglutinin of influenza A virus could be specifically measured by single radial hemolysis (SRH) when test antigens were recombinant viruses containing the relevant H3 hemagglutinin antigen and irrelevant Neq1 neuraminidase of A/equine/Prague/1/56 virus. Antibodies to influenza B virus could also be measured by the SRH technique. Antibody rises to influenza A or B virus measured by SRH agreed with results of hemagglutination inhibition (HI) tests for about 80% of the sera tested, including sera from volunteers receiving killed influenza vaccine and sera from patients naturally infected with influenza. Correlation between antibody titers measured by SRH and HI was also good. Antibodies to the N2 neuraminidase of influenza A virus could be specifically measured by SRH when test antigens were recombinant viruses containing the relevant N2 neuraminidase antigen and irrelevant Heq1 hemagglutinin of A/equine/Prague/1/56 virus. The SRH test for neuraminidase antibodies was more strain specific than was the SRH test for hemagglutinin antibodies. Probably for this reason, agreement between neuraminidase antibody determinations in human sera by the SRH test and by the neuraminidase inhibition test was poorer than agreement between the SRH test for hemagglutinin antibodies and the HI test.

Measurement of antibody to influenza virus neuraminidase by single radial hemolysis in agarose gels.

A simple method of assaying anti-influenza neuraminidase antibodies in human sera was described. Suitable antigenic hybrid viruses were adsorbed to sheep erythrocytes, which were then incorporated into agarose gels. When sera were introduced into wells cut in the gels, zones of hemolysis were observed in the neighborhood of those containing neuraminidase antibodies. There was a direct relationship between zone size and antibody titer. No purification of adsorbed viruses was necessary. The test was rapid, required very simple reagents, gave results that agreed well with those given by conventional techniques, and appeared to be the most sensitive of four methods evaluated. Studies of cross-reactions by hyperimmune sera against homologous and heterologous neuraminidases and of absorption of neuraminidase antibodies from human sera indicated a high degree of specificity. The technique seems to be suitable for large-scale epidemiological investigations.

Measurement of parainfluenza-3 virus antibody by the single radial hemolysis technique

A single radial hemolysis assay for parainfluenza-3 virus antibody is described as a simple, sensitive, accurate, and precise alternative to hemagglutination inhibition and serum neutralization tests. A highly significant correlation exists between single radial hemolysis zone areas and hemagglutination inhibition titers of both serum and nasal secretion samples. Antibody conversions equivalent to as little as a twofold rise in hemagglutination inhibition titer are readily and reliably detected in sera and nasal secretions. Single radial hemolysis and hemagglutination inhibition activity was demonstrable in the immunoglobulin G fraction of a hyperimmune parainfluenza-3 virus antiserum.

Methodology a study of the single radial hemolysis in gel system-III. Quantitation of complement

Application of the RHG method for quantification of complement (C′) is described. The measurements of potency obtained by the radial hemolysis in gel plates for different lots of C′ agree with the values obtained by conventional tube titration. With properly standardized plates, the RHG method can determine the CH 50 units of different lots of C′ using an experimentally determined area of lysis ( y) value obtained for CH 50/ml. This also allows the estimation of residual CH 50/ml after complement fixation by antigen-antibody.

Methodology a study of the single radial hemolysis in gel system-III. Quantitation of complement

Methodology a study of the single radial hemolysis in gel system-III. Quantitation of complement

A study of the single radial hemolysis in gel system—II application of the model to mouse 19S hemolytic antibodies

A study of the single radial hemolysis in gel system—II application of the model to mouse 19S hemolytic antibodies

A study of the single radial hemolysis in gel system—I factors affecting the model

Mouse hemolytic 19S antibodies can be quantitatively measured if they are allowed to radially diffuse in an agar plate containing the erythrocyte antigen. After diffusion and subsequent lysis with complement a linear relationship can be seen between the area of lysis and the square root of the antibody dilution. It is found that the temperature does not affect the area of lysis obtained; however, the erythrocyte concentration, agar concentration and time do affect the slope of the line for any antibody preparation. When care is taken, only 4·37 per cent error was observed.

A study of the single radial hemolysis in gel system—II application of the model to mouse 19S hemolytic antibodies

A quantitative method for the determination of mouse anti-SRBC has been described in the previous paper (Hiramoto et al., 1971). The mathematical formulation used to derive the slope was least square; theoretical and practical uses of these comparisons are given below. In addition, reconstruction experiments were performed to further test this system. In the first experiment, an antiserum was partially diluted and then compared with a different antiserum standard. In the second experiment, the same antiserum was diluted by one-third and compared with the original.

A study of the single radial hemolysis in gel system—I factors affecting the model

A study of the single radial hemolysis in gel system—I factors affecting the model