Functional studies on purified eosinophils and neutrophils from patients with Schistosoma mansoni infections.

Unpurified peripheral blood leucocytes or purified eosinophils and neutrophils from patients with schistosomiasis and from normal individuals were compared for their ability to interact with antibody coated schistosomula of Schistosoma mansoni. There was no difference in the ability of buffy coat cells or neutrophils from patients and from normal individuals to mediate antibody-dependent 51Cr release from labelled schistosomula. However, eosinophils from patients were significantly better than those from normal individuals in causing antibody-dependent 51Cr release. This enhanced activity of eosinophils from patients with schistosomiasis was found to correlate with the intensity of their infection as judged by faecal egg counts. Eosinophils from patients also contained a higher proportion of cells with detectable Fc receptors than those from normal individuals. It is suggested that the difference in the behaviour of eosinophils from patients and from normals may reflect an 'activated' state of these cells in the infected individuals.