Human Plasma Proteome During Normal Pregnancy

The
human plasma proteome is underexplored despite its potential
value for monitoring health and disease. Herein, using a recently
developed aptamer-based platform, we profiled 7288 proteins in 528
plasma samples from 91 normal pregnancies (Gene Expression Omnibus
identifier GSE206454). The coefficient of variation was <20% for
93% of analytes (median 7%), and a cross-platform correlation for
selected key angiogenic and anti-angiogenic proteins was significant.
Gestational age was associated with changes in 953 proteins, including
highly modulated placenta- and decidua-specific proteins, and they
were enriched in biological processes including regulation of growth,
angiogenesis, immunity, and inflammation. The abundance of proteins
corresponding to RNAs specific to populations of cells previously
described by single-cell RNA-Seq analysis of the placenta was highly
modulated throughout gestation. Furthermore, machine learning-based
prediction of gestational age and of time from sampling to term delivery
compared favorably with transcriptomic models (mean absolute error
of 2 weeks). These results suggested that the plasma proteome may
provide a non-invasive readout of placental cellular dynamics and
serve as a blueprint for investigating obstetrical disease.