Immunolatex particles were used as markers for IgE receptors on basophils using electron-microscope scanning. These particles appeared to bind specifically to basophils. Basophils from atopic asthma patients showed greater binding to latex particles than those from intractable asthma patients or healthy subjects. Cap and patch formations on IgE receptors were frequently found in basophils of atopic asthmatics, and cap formation was observed only on basophils that were pear-shaped. The redistribution of IgE receptors, such as that by cap formation, may be a significant triggering mechanism for basophil activation.

The latex density on basophils pre-treated with anti-human IgG was much greater in intractable asthmatics than in atopic asthmatics or healthy subjects, and almost all basophils with increased immunolatex particles were pear-shaped, suggesting the presence of some IgG receptors on the surface, and such receptors may play an important role in intractable asthma.