title: The ultrastructure of a porcine hereditary lymphoma with some observations on cell cultures and enzyme cytochemistry.
abstract: Ultrastructural studies have been made on affected tissues and cell cultures established from an hereditary lymphosarcoma of Large White pigs. Certain hydrolytic and lysosomal enzymes have been investigated at light microscope level in tumour cells and in cells established in culture. Morphological, behavioural and enzymatic characteristics indicate that two types of surface-adherent cells persist in primary cultures established from the marrow of affected pigs, namely macrophages and myeloid cells. The latter show an initial tendency to colonial growth which disappears in subsequent passages. In nearly all cases the tumour is considered to be a poorly differentiated lymphocytic lymphosarcoma. There is, however, considerable variation in cellular components and tumour-cell differentiation, and on purely morphological grounds one case might be considered to be an histiocytic i.e. macrophage lymphoma. Intra-nuclear bodies were observed in one case and occasional cytoplasmic virus-like particles were seen in both fresh tissues and cultured cells. In older pigs tumorous lymph nodes often show a cellular depletion associated with an increase of fibroreticular stroma.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D008198:Lymph Nodes / Q000648:ultrastructure; D008221:Lymphoid Tissue / Q000648:ultrastructure; D008228:Lymphoma, Non-Hodgkin / Q000201:enzymology / Q000235:genetics / Q000648:ultrastructure / Q000662:veterinary*; D008854:Microscopy, Electron; D013552:Swine; D013553:Swine Diseases / Q000235:genetics / Q000473:pathology*