USE OF THE MIXED HAEMADSORPTION TECHNIQUE TO DEMONSTRATE LECTINS ADSORBED TO MONOLAYER CULTURES

Abstract

The radial diffusion mixed haemadsorption test was found to be a convenient, specific, sensitive and reproducible procedure by which to demonstrate the presence of phytohaemagglutinin (PHA) and concanavallin A (Con A) on the surface of monolayer cultures. When 100–500 μg/ml of PHA or Con A was included in the culture medium for 24 hours, an easily demonstrable concentration of the lectin was attached to the culture and remained so for at least 60 days. The heterogenicity of the commercial PHA preparations used was reflected by the fact that only the homologous antiserum gave filled haemadsorption zones with Difco PHA. An anti Wellcome PHA gave ring‐ or target zones with both the homologous and the Difco PHA. Also the anti‐Difco PHA serum gave ring‐ or target zones with the Wellcome PHA. The ring zone effect obtained with Wellcome PHA, therefore, depended on the properties of this antigen and most probably on the fact that the Wellcome preparation was more homogenous and therefore contained less antigenic specificities than the Difco preparation.