A robust intracellular metabolite extraction protocol for human neutrophil metabolic profiling

BACKGROUND: Neutrophils are phagocytic innate immune cells that play essential roles in host defence, but are also implicated in inflammatory diseases such as rheumatoid arthritis (RA) where they contribute to systemic inflammation and joint damage. Transcriptomic analysis of neutrophils has revealed significant changes in gene expression in neutrophils activated in vitro by cytokines and in vivo during inflammation in RA. However, there are no reports on the global metabolomic changes that occur during neutrophil activation. The aim of this study was to establish protocols for the study changes in the metabolome of human neutrophils using 1H NMR spectroscopy.