Intracerebral Passage of Sarcoma 180 in Mice and Hamsters. ∗

Summary

Mouse sarcoma 180 has been through a total of more than 25 IC passages in suckling and adult mice. Sarcomatous brain suspensions also produced sarcomas in adult mice by subcutaneous route. The IC route in suckling mice was about 1,000 times as effective as subcutaneous route in adult mice. After serial IC passages in suckling mice the sarcoma was adapted to suckling hamsters by IC injection and to date more than 12 serial passages have been carried out in this animal. A strain of sarcoma 180 cells which has undergone more than 25 TC passages produced sarcomas regularly in adult mice after subcutaneous injection and required about 500,000 cells to give 100% “takes.” However, when inoculated IC into suckling mice these cells seemed less neurotropic than mouse (IC) passage sarcoma cells.