Photo by Graham Colm
A new method for identifying immune cells could pave the way for rapid detection of hematologic malignancies from a small blood sample, according to researchers.
The team found they could use wavelength modulated Raman spectroscopy (WMRS) to identify subsets of T cells, natural killer cells, and dendritic cells.
Traditional methods of identifying these cells usually involve labeling them with fluorescent or magnetically labeled antibodies.
Using WMRS, the researchers were able to identify immune cells with no labeling at all, thus permitting rapid identification and further analysis to take place with no potential alteration to the cells.
Simon Powis, PhD, of the University of St Andrews in Fife, Scotland, and his colleagues described this work in PLOS ONE.
Raman scattering refers to light scattering from molecules in a sample where the light energy can be shifted up or down and recorded as a “molecular fingerprint” that can be used for identification. Normally, this process is very weak and further hampered by other background light (eg, fluorescence).
WMRS subtly changes the incident laser light that, in turn, results in a modulation of the Raman signal, allowing it to be extracted from any (stationary) interfering signal.
Using WMRS, Dr Powis and his colleagues found they could identify CD4+ T cells, CD8+ T cells, CD56+ natural killer cells, CD303+ lymphoid/plasmacytoid dendritic cells, and CD1c+ myeloid dendritic cells.
“Under a normal light microscope, these immune cells essentially all look identical,” Dr Powis said. “With this new method, we can identify key cell types without any labeling.”
“Our next goal is to make a full catalogue of all the normal cell types of the immune system that can be detected in the bloodstream. Once we have this completed, we can then collaborate with our clinical colleagues to start identifying when these immune cells are altered, in conditions such as leukemia and lymphoma, potentially providing a rapid detection system from just a small blood sample.”
