Transmission of Myeloid Leukemia of Mice

A transmissible strain of myeloid leukemia of mice is described. It can be readily passed from diseased to healthy mice by the transfer of tissues that contain live cells; but inoculation fails when the latter are not present. Inoculation is successful in almost every mouse whose resistance is lowered by X-rays. It is often successful in mice related to the animal in which the spontaneous leukemia took its origin, and occasionally successful in mice unrelated to it. The systemic diffuse disease (myeloid leukemia) is produced only by intravenous inoculation with relatively large doses, whereas subcutaneous or intraperitoneal inoculation results in the formation of tumors composed of myelocytes with basophile granules, in other words malignant blood cells of the strain described. Intravenous inoculation with small doses in susceptible mice, or similar inoculation with larger doses in somewhat resistant mice, results in the formation of tumors composed of myelocytes (multiple myeloma).