NCAM1 and neoplasm: Thus, researchers can label immune effector cells and tumour cells with proper fluorescent dye or antibodies to visually investigate how natural products affect target cell killing, effector-target cell conjugation, and immune effective molecular production, such as CD56 antibody for human NK cells, carboxyfluorescein succinimidyl ester (CFSE) for tumour cells, propidium iodide (PI) for dead cells, and interferon antibody for immune-effective molecules.