Tracing Hematopoietic Progenitor Cell Neutrophilic Differentiation via Raman Spectroscopy

Abstract

A major challenge to experimental studies and therapeutic uses of hematopoietic stem cells (HSC) is the limited options for analytical tools that can reliably resolve functional differences in heterogeneous HSC subpopulations at the single cell level. Currently available methods require the use of external labels and/or separate clonogenic and transplantation assays to identify bona fide stem cells, necessitating the harvest of bulk cell populations and long incubation times that obscure how individual HSCs dynamically respond to exogenous and endogenous stimuli. In this study, we employ Raman spectroscopy to noninvasively resolve the dynamics of individual differentiating hematopoietic progenitor cells during the course of neutrophilic differentiation. We collected Raman peaks of individual cells daily over the course of 14-day neutrophilic differentiation. Principal component analysis (PCA) of the Raman peaks revealed spectral differences between individual cells during differentiation that were strongly correlated with changes in the nucleus shape and surface antigen expression, the primary traditional means of monitoring neutrophilic differentiation. Additionally, our results were consistently reproducible in independent rounds of neutrophilic differentiation, as demonstrated by our partial least-squares discriminant analysis (PLS-DA) of the Raman spectral information that predicted the degree of neutrophilic differentiation with high sensitivity and specificity. Our findings highlight the utility and reliability of Raman spectroscopy as a robust molecular imaging tool to monitor the kinetics of HSC differentiation patterns.

A single-cell Raman-based platform to identify developmental stages of human pluripotent stem cell-derived neurons

“…Raman microspectroscopy is a label-free technique which has been applied to study phenotypes of single cells ( 13 – 15 ). It is a nondestructive vibrational spectroscopy based on inelastic scattering of light, reflecting the intrinsic biochemical profiles of cells ( 16 ).…”

Development of an Inexpensive Raman-Compatible Substrate for the Construction of a Microarray Screening Platform

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Raman fingerprints as promising markers of cellular senescence and aging

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