Neuroblastoma cells. Immunofluorescent Light Micrograph of human neuroblastoma cancer cells. Neuroblastoma is a tumour derived from primitive nerve cells, most commonly in the medulla of the adrenal gland. Here the cytoplasm of neuroblastoma cells stains red for polysialic acid; nuclei are blue; normal epithelial cells stain green. As a malignant tumour in children, neuroblastoma may spread via the blood into the bones and liver. Immunofluorescence is a staining technique which uses antibodies to attach fluorescent dyes to specific tissues and to molecules in the cell. Magnification: x250 at 5x7cm size. x125 at 35mm