Human maternal plasma proteomic changes with parturition

The powerful proteomic technique of Tandem Mass Tag labelling with Orbitrap mass spectrometry was applied to the quantification of relative levels of proteins in serial plasma samples from 15 women prior to and during labour. Quantitative data were obtained for 1038 proteins, with 217 quantified in ≥10 sample pairs. Most proteins were unaffected by labour, 32 had lower levels in labour, and two were increased in labour, and the t test had sufficient power to determine a significant difference in expression in 14 proteins. ELISA confirmed the significant increase of acute phase response components C-reactive protein and serum amyloid A. Proteomic technology is constantly advancing, and the latest techniques enable gel-free analysis of minimally preprocessed, complex biological samples, enabling simultaneous identification and quantification of many hundreds of proteins. The technique of TMT labelling and Orbitrap mass spectrometry is applicable to the analysis of serial maternal plasma samples in order to identify potential markers of the onset of labour.