Transcriptome analysis on mesenchymal stem cells derived from placenta and blood in preeclamptic pregnancies

Hypertensive pregnancy disorders affect 10% of pregnancies worldwide. It is an important cause of maternal, perinatal morbidity and mortality. Preeclampsia (PE), which is a hypertensive pregnancy disease, is a condition where systolic blood pressure is 140 mmHg or above, and diastolic blood pressure is 90 mmHg or above as a result of repeated measurements made after the 20th week of pregnancy. In addition to hypertension, proteinuria and maternal organ dysfunction can also be seen. Placental development is incomplete and insufficient as well as implantation in pregnant women with preeclampsia. Disturbances in spiral artery remodeling experienced during placenta formation cause tissue to be deprived of oxygen and trigger hypoxia. Maternal release of anti-angiogenic factors occurs with oxidative stress. Imbalance between angiogenic and anti-angiogenic factors causes disruptions in angiogenesis and placental vascularity. Mesenchymal stem cells (MSCs) are self-renewable cells with the potential to differentiate into special cell lines. MSCs are thought to play a role in regulating the proangiogenic, immunomodulatory and anti-inflammatory environment of the maternal-fetal interface during placentation. Placenta is widely studied as a source of MSC. There are MSC studies isolated from different parts of the placenta. The fact that the placenta is a vascular organ suggests that there may be a more dominant angiogenic profile in MSCs isolated from this tissue. Accessibility and high potential for differentiation have also been an alternative to blood-derived stem cells as a promising resource for medical applications. There are studies of MSCs derived from peripheral blood, but insufficient amount of MSC after isolation is reflected in studies as a limiting factor. This thesis covers the mRNA expression analysis of decidua and peripheral blood-derived MSCs from PE and healthy pregnant women and is a preliminary study to investigate possible biomarkers.Within the scope of the thesis, gene expression analysis was studied by isolating MSCs from a total of 28 samples from placental tissue and peripheral blood belonging to seven pregnant women with preeclapsia and seven healthy pregnant women. After isolation and culture of MSCs, cell sorting was performed by using flow cytometry method by means of appropriate cell surface markers after increasing cell density as desired. Total RNA was isolated from MSCs and translated into cDNA. For gene expression analysis, "Vascular Endothelial Growth Factor A" (VEGF (A)), "Metallopeptidase Inhibitor 1" (TIMP-1), "Ephrin A3" (EFNA3), "Thrombospondin Type 1 7A" (THSD7A) and for normalization Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used. Gene expression analysis was performed by droplet digital polymerase chain reaction (ddPZR) method. "Graphpad Prism Version 8.3.0" program was used for the statistical results of the data. The significance of the results was evaluated using the nonparametric "Mann Whitney Test". "Reciever Operating Characteristic" (ROC) analysis was performed for specificity and sensitivity. As a result of the analyzes, TIMP-1, EFNA3 and THSD7A were not evaluated statistically significant although there were fold changes in the level of mRNA expression in both decidua and peripheral blood MSCs. Although there was a fold change in the mRNA expression level in VEGF (A) decidua MSCs, it was not considered statistically significant because it did not meet the condition of p <0.05, but a 4.2 fold increase in VEGF (A) level in peripheral blood-derived MSCs of PE patients was observed (AUC: 0.95 p = 0.019). It was considered to be statistically significant since it met the condition of p <0.05. This study was conducted to observe whether there is a change in gene expression at the stem cell level of genes thought to have effects on angiogenesis in parallel with the pathogenesis of preeclampsia. In line with these results, it can be predicted that the significant increase in VEGF (A) level in MSCs obtained from peripheral blood can be used as a potential biomarker and the therapeutics can be used as target gene in the treatment of PE in the future.