Haemopoietic progenitor-cell responses in mice with the transplanted lymphoid leukaemia ABE-8.

BALB/c mice bearing the transplanted lymphoid tumour ABE-8 developed increased levels of neutrophil, macrophage and eosinophil progenitor cells in the marrow and spleen. Neutrophil-macrophage progenitors, assayed as granulocyte-macrophage colony-forming cells in agar, increased in number only if invasion of the marrow or spleen by ABE-8 cells was demonstrable. Rises in B-lymphocyte colony-forming cells occurred whether or not there was invasion of the host spleen or marrow. No increase in progenitor cells was found in mice bearing diffusion chambers containing ABE-8 cells. The magnitude of leukaemic infiltration was determined by assaying numbers of leukaemic stem cells in the spleen and marrow using a selective cloning system. This transplanted lymphoid leukaemia appears to be a useful model for analysing the effects of haemopoietic tumours on host haemopoietic tissues.