This work was a collaborative effort between Geert van den Bogaart, theme Cancer development and immune defense, and Simona Cristescu from the Life Science Trace Gas Facility at Radboud University.
This publication is part of the PhD project of Laurent Paardekooper (photo) and reveals how ethylene can be detected in breath as a biomarker for systemic inflammation. ‘Ethylene is mostly known as a plant hormone mediating developmental processes and stress responses to stimuli such as infection. We now show that systemic inflammation triggers ethylene production in humans, which is released in breath.’ The authors demonstrate that ethylene is a lipid peroxidation product formed by the respiratory burst. Ethylene was detected by photoacoustics both in vitro from isolated white blood cells exposed to bacterial lipopolysaccharide (LPS) as well as in vivo following injection of LPS in healthy volunteers. In vivo, the ethylene release even preceded the rise of inflammatory markers in blood. ‘Our results highlight that ethylene release is an integral component of in vivo lipid peroxidation with clinical potency as an economical respiratory biomarker of bacterial infection.’