Differences and Similarities in the Transcriptional Profile of Peripheral Whole Blood in Early and Late-Onset Preeclampsia: Insights into the Molecular Basis of the Phenotype of Preeclampsia
Chaiworapongsa, T., Romero, R., Whitten, A., et al.
Preeclampsia (PE) has been sub-divided into early- and late-onset phenotypes. The pathogenesis of these two phenotypes has not been elucidated. To gain insight into the mechanisms of disease, the transcriptional profiles of whole blood from women with early- and late-onset PE were examined.
A cross-sectional study was conducted to include women with: 1) early-onset PE (diagnosed prior to 34 weeks, n=25); 2) late-onset PE (after 34 weeks, n=47); and 3) uncomplicated pregnancy (n=61). Microarray analysis of mRNA expression in peripheral whole blood was undertaken using Affymetrix microarrays. Differential gene expression was evaluated using a moderated t-test (false discovery rate <0.1 and fold change >1.5), adjusting for maternal WBC count and gestational age. Validation by real-time qRT-PCR was performed in a larger sample size [early PE (n=31), late PE (n=72) and controls (n=99)] in all differentially expressed genes. Gene Ontology analysis and pathway analysis were performed.
1) 43 and 28 genes were differentially expressed in early- and late-onset PE compared to the control group respectively; 2) qRT-PCR confirmed the microarray results for early and late-onset PE in 77% (33/43) and 71% (20/28) of genes, respectively; 3) 20 genes that are involved in coagulation (SERPINI2), immune regulation (VSIG4, CD24), developmental process (H19) and inflammation (S100A10) were differentially expressed in early-onset PE alone. In contrast, only seven genes that encoded proteins involved in innate immunity (LTF, ELANE) and cell-to-cell recognition in the nervous system (CNTNAP3) were differentially expressed in late-onset PE alone. Thirteen genes that encode proteins involved in host defense (DEFA4, BPI, CTSG, LCN2), tight junctions in blood-brain barrier (EMP1) and liver regeneration (ECT2) were differentially expressed in both early- and late-onset PE.
Early- and late-onset PE are characterized by a common signature in the transcriptional profile of whole blood. A small set of genes were differentially regulated in early- and late-onset PE. Future studies of the biological function, expression timetable and protein expression of these genes may provide insight into the pathophysiology of PE.
Chaiworapongsa, T., Romero, R., Whitten, A., et al. "Differences and Similarities in the Transcriptional Profile of Peripheral Whole Blood in Early and Late-Onset Preeclampsia: Insights into the Molecular Basis of the Phenotype of Preeclampsia" Journal of Perinatal Medicine (2014): 485–504