Induction, isolation and surface marker studies on bovine eosinophils.

A crude extract from Ascaris suum was infused into the teat canal of heifers to serve as an irritant or an antigens. The cells present in the mammary gland following such stimulation were assessed over a period of 2 weeks. Prior to stimulation there were few cells, predominantly macrophages, however, by 12 h post-stimulation a larger number of eosinophils and neutrophils were present. The eosinophils, which represented approximately 50% of the total population, could be purified by Ficoll-Hypaque flotation and nylon or glass wool column filtration to yield a population consisting of over 90% eosinophils. Surface marker studies on the purified eosinophils revealed that they contained both Fc and complement receptors.