The quantitation of rabies-specific antibodies. II. Factors affecting the sensitivity of the haemagglutination inhibition test.
Various factors affecting the HAI test for the quantitation of rabies-specific antibodies have been evaluated with a view to obtaining maximum sensitivity and reproducibility in tests using tissue culture antigens prepared in vero cells and concentrated by dialysis. Goose erythrocytes treated with proteolytic enzyme bromelian at a concentration of 0.025% were much more susceptible to HA than those that were untreated or erythrocytes treated with neuraminidase. In addition, other parameters like the use of a phosphate buffered saline (PBS) as a diluent at pH 6.2, incubation at 0-4 degrees C for 1.5-3 h were found to be most critical for achieving maximum HA activity. To remove non-specific inhibitors, serum samples were treated with aerosil, acetone in combination or alone. Of the 73 serum samples tested, removal of non-specific inhibitors by aerosil alone occurred in up to 54.79% of the samples, whereas using acetone-aerosil treatment followed by adsorption with goose erythrocytes, the inhibitors were removed in 98.67% of the samples to a level that was undetectable at the 1:4 starting dilution in the HAI test.
Chauhan
A
A
Department of Hepatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Sood
D K
DK
Saha
S M
SM
Aggarwal
R K
RK
Saxena
S N
SN
D000096:Acetone; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D004912:Erythrocytes; D005069:Evaluation Studies as Topic; D005777:Geese; D006385:Hemagglutination Inhibition Tests; D006386:Hemagglutination Tests; D006801:Humans; D006863:Hydrogen-Ion Concentration; D011819:Rabies Vaccines / Q000494:pharmacology; D011820:Rabies virus / Q000276:immunology*; D012680:Sensitivity and Specificity; D013696:Temperature
D000914:Antibodies, Viral; D011819:Rabies Vaccines; D000096:Acetone