National Institute of Biotechnology Malaysia (NIBM) 1 article published in JoVE Cancer Research Time-Lapse 2D Imaging of Phagocytic Activity in M1 Macrophage-4T1 Mouse Mammary Carcinoma Cells in Co-cultures Noorzaileen Eileena Zaidi1, Nur Aima Hafiza Shazali2, Adam Leow Thean Chor1, Mohd Azuraidi Osman1, Kamariah Ibrahim3, Marilyn Jaoi-Edward4, Nik Mohd Afizan Nik Abd Rahman1,2 1Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 2Institute of Tropical Forestry and Forestry Products (INTROP), Universiti Putra Malaysia, 3Department of Biomedical Science, Faculty of Medicine, University of Malaya, 4Agro-Biotechnology Institute (ABI), National Institute of Biotechnology Malaysia (NIBM) Macrophage phagocytic activity against cancer cells, specifically 4T1 mouse mammary carcinoma cells, was imaged in this study. The live cell coculture model was established and observed using a combination of fluorescent and differential interference contrast microscopy. This assessment was imaged using imaging software to develop multipoint time-lapse video.