Further studies on tumour‐producing activity in adult mice by embryonic tissue cultures exposed to a virus and grafted before manifestation of morphologic transformation

Abstract

Experiments were carried out to test the possibility of tumour production in adult recipients of different mouse strains by syngeneic embryonic tissue cultures exposed to, and not transformed by several oncogenic viruses. Tumour‐producing effect of embryonic tissue cultures exposed to C‐Z strain of RSV was observed in 100% of A, C3H‐H2p, AKR, C57BL/Sn, CC57W and in a small proportion of CC57BR mice, but not in B10.D2 and BALB/c mice. However, introduction of infected embryonic tissue cultures, originating from the resistant strains of mice, into F1 hybrids between the opposite strains resulted in tumour production. It was demonstrated that resistance to tumour production of the three strains mentioned above was not mediated by the strong immune reaction against the cells introduced. Tumour‐producing effect by infected but untransformed cells was also seen with the C‐Z strain in hamsters, with the S‐R strain of RSV in mice, and with the 5D strain in hamsters but not in mice. Attempts to produce tumours in mice by the introduction of syngeneic embryonic tissue culture exposed to SV40 and neurotropic strain (WSN) of influenza A viruses were negative.

Isolation and characterization of membranes from normal and transformed tissue-culture cells

“…Changes in composition (Buck et al, 1970;Dijong et al, 1971;Kryukova et al, 1971;Perdue et al, 1971a;Renkonen et al, 1972), function (Hatanaka & Hanafusa, 1970;Peery et al, 1971;Perdue et al, 1971b) and structure (Inbar et al, 1972a,b) of the surface membrane of tissue culture cells have been implicated in the phenomenon of 'transformation' of these cells by viruses. Central to much of this work is the preparation of a surface membrane fraction of well-established purity that is functionally intact.…”