Lack of knowledge of underlying biology and effective treatments for brain tumors, remains an unmet medical need. Recent reports suggest that phagocytosis, in which a type of immune cells, called macrophages, engulf foreign bodies, may have a role in treating brain tumors. The objectives of this project were to grow brain tumor cell lines and establish the optimal growth conditions; and then to study the role of phagocytosis in the treatment of gliomas. Oligodendroglioma (BT142) (unsorted) and Medulloblastoma (MB002) cell lines (unsorted & sorted) were thawed and plated to grow in Oligodendroglioma media. Cells were checked regularly under a microscope to monitor for cell growth, and under a fluorescent microscope for cell viability. The BT142 cell line initially grew (#2 days) and small clusters formed, but then by day 10 it stopped growing and cells started to die by day 16. For the MB002 unsorted cell line, the number of cells increased from 0-4 days, but stopped growing and cells died from 4-6 days. On the other hand, MB002, the sorted cell line enriched for tumor cells, consistently grew and had to be split. The data generated so far has established the optimal growth conditions for oligodendroglioma and medulloblastoma brain tumor cells lines. The observation that the sorted cell line grew while the unsorted did not is likely due to the higher percentage of tumor cells. In the future, different cell populations will be labeled to conduct a phagocytosis assay.