[Independence of tumor cell affinity for lung tissue from its interaction with unfixed macrophages]

The selection of tumor cells for their affinity to pulmonary tissue significantly enhances their ability to invade and proliferate. The intraveneous inoculation of these cells into mice increases the number of animals bearing tumour clones and the number of clones per animal. The adduction of unfixed macrophages by means of intramuscular injection of BGG, which is known to increase the implanted tumour growth, did not increase either the percentage of animals bearing tumor cell clones or the number of clones per a lung, in our experiments. The affinity of tumor cells to pulmonary tissue obviously does not depend significantly on the interaction with unfixed macrophages. We assume that the selection of tumor cells for their affinity to pulmonary tissue is not necessarily connected with changes in their antigenous properties for recipient animals.