Virus-cell Relationship in Kidney Tumours Induced in Golden Hamsters by the Mill Hill Polyoma Virus

MILL HILL polyoma virus (M.H.P.) was isolated from the spleen of a leukaemic AK mouse in 1959 (Negroni, Dourmashkin and Chesterman, 1959). It has many properties in common with the Stewart and Eddy polyoma virus (Stewart, Eddy

The Structure of Tumours Derived from Mouse Cells after “Spontaneous” Transformation in vitro

The histological structure of 58 primary tumours derived from spontaneously transformed tissue culture cell lines from embryonic (14-16 days), young (3-20 days) and old (28-34 months) C3H and C57 mice is described. Although the cell lines were derived from a number of different organs the tumours were similar in morphology. The pattern was mixed, with “fibrosarcomatous”, “myxoid”, “epithelioid” and giant cell areas. The tumours resemble some types of haemangiopericytoma

Immunological Control of Polyoma Virus Oncogenesis in Mice

Adult CBA mice thymectomized, treated with antilymphocytic globulin (ALG) and inoculated with human leprosy organisms were accidentally infected with polyoma virus and all developed tumours. After cessation of ALG administration, some animals were given spleen cells from syngeneic donors immunized with polyoma virus; none developed tumours. Similar results were obtained in mice deliberately infected with polyoma virus but not with leprosy organisms. Passive transfer of antibody before but not after virus inoculation prevented tumour formation in immunosuppressed recipients. Virus infection in thymectomized, lethally irradiated and bone marrow reconstituted mice resulted in only a very low incidence of tumours. These results emphasize the role of immunological surveillance in preventing polyoma tumour formation under natural conditions