This assay is optimized for fluorescence, inverted microscopic images of immune cells, such as T-cells, moving toward pathogen cells, such as tumor cells.
Fluorescence microscopy describes a technique that uses fluorescence instead of the reflection or absorption of light. In order for a sample to be used, it must be fluorescent either naturally or from special preparation by the researcher. The sample is then illuminated by light from one or more wavelengths which excite the fluorophores causing them to emit light of a different wavelength. The illuminated light is filtered out and the remaining light is from the sample.