Figure 1.
Phagocytosis of tumor cells by antigen-presenting cells. Phagocytosis of lymphoma cells by macrophages (A) or dendritic cells (B) was determined by microscopic counting after a 2-hour incubation. Tumor cells were left untreated (NT), induced in apoptosis by γ-irradiation (APO), in necrosis by heating (NEC), or opsonized by rituximab (OPS). Cells were cyto-centrifuged and stained with May-Grünwald-Giemsa and phagocytosis was evaluated by microscopic counting. The data shown are the mean + SD of 5 experiments, and indicate the percentage of phagocytes containing at least one tumor cell.