Abstract
Methods used to separate macrophages from human lympho-medullary tissue samples have been applied to involved and uninvolved spleens and lymph nodes from 44 patients with Hodgkin's disease. The tumour samples yielded a population of ultrastructurally atypical cells with the anatomical and functional attributes of macrophages. The findings suggest that the macrophage was the neoplastic element in the cases of Hodgkin's disease studied. A feature of samples of uninvolved tissue from Hodgkin's disease patients was that there were fewer macrophages identifiable in the samples than in normal control tissues. These findings suggest that there may be a deficiency of normal macrophages as well as macrophage ncoplasia in this disease. Both abnormalities would contribute to the defective cell-mediated immunity which is a characteristic of Hodgkin's disease.