Preeclampsia remains a leading cause of maternal and fetal mortality, due to ineffective treatment and diagnostic strategies, compounded by the lack of clarity on the etiology of the disorder. Although several clinical and biological markers of preeclampsia have been evaluated, they have proven to be ineffective in providing a definitive diagnosis during the various stages of the disorder. Exosomes have emerged as ideal biomarkers of pathological states, such as cancer, and have more recently gained interest in pregnancy-related complications, due to their role in cellular communication in normal and complicated pregnancies. This occurs as a result of the specific placenta-derived exosomal molecular cargo, which may be involved in normal pregnancy-associated immunological events, such as the maintenance of maternal–fetal tolerance. This review provides perspectives on placenta-derived exosomes as possible biomarkers for the diagnosis/prognosis of preeclampsia. Using keywords, online databases were searched to identify relevant publications to review the potential use of placenta-derived exosomes as biomarkers of preeclampsia.

Background: Preeclampsia is the leading cause of maternal and fetal mortality due to the inability to diagnose and treat the disorder early in pregnancy. This is attributed to the complex pathophysiology and unknown etiology of the disorder, which is modulated by several known and unknown factors. Exosomes have recently been implicated as possible mediators of the pathogenesis of preeclampsia, with, however, no evidence linking these nanovesicles to the pathophysiology of preeclampsia and its subtypes. Methods: To better understand the pathophysiological role of exosomes in preeclampsia, we have analyzed the exosomal microRNA in early and late onset preeclamptic women in comparison to their gestationally matched normotensive controls using Digital Direct Detection (NanoString Technologies). Results: For the first time, distinct exosomal microRNA signatures in early and late onset preeclampsia have been identified. Moreover, these signatures indicate that exosomes are involved in key pathological features associated with preeclampsia and differentiate between the subtypes. Conclusion: This study forms the basis for the diagnostic and functional validation of the identified signatures as biomarkers of preeclampsia and its subtypes.

The biological links between cancer and pregnancy are of recent interest due to parallel proliferative, immunosuppressive and invasive mechanisms between tumour and trophoblast development. Therefore, understanding “cancer-like” mechanisms in pregnancy could lead to the development of novel cancer therapeutics, however, little is understood on how tumour and trophoblast cells recapitulate similar molecular mechanisms. Based on our observations from a previous study, it was not only evident that exosomal miRNAs are involved in the pathophysiology of preeclampsia but also contained cancer-specific miRNAs, which suggested that “pseudo-malignant-like” exosomal-mediated mechanisms exist in pregnancy. The presented study therefore aimed to identify exosomal miRNAs (exomiR) in pregnancy which can be repurposed towards preventing tumour metastasis and immunosuppression. It was identified that exomiR-302d-3p, exomiR-223-3p and exomiR-451a, commonly associated with cancer metastasis, were found to be highly expressed in pregnancy. Furthermore, computational merging and meta-analytical pathway analysis (DIANA miRPath) of significantly expressed exomiRs between 38 ± 1.9 vs. 30 ± 1.11 weeks of gestation indicated controlled regulation of biological pathways associated with cancer metastasis and immunosuppression. Therefore, the observations made in this study provide the experimental framework for the repurposing of exosomal miRNA molecular mechanisms in pregnancy towards treating and preventing cancer.

This study investigates the efficacy of certain biosorbents as a filtration method to reduce chlorination and its costs in wastewater treatment. A two-step filtering process was used, with each phase containing 200 mL of bacterially contaminated water that was passed through 100 g of biosorbents. Colony forming units were counted using routine plate counts to determine the bacterial load reduction in filtered and unfiltered water. SEM–EDX analysis was used to investigate changes in particle size, elemental composition and structural changes in biosorbents, whereas hydraulic flow rate estimates determined material permeability. Adsorption decreased bacterial concentrations in all biosorbents. Although cow bone had the highest flow rate (4.62 E-06 m³/hr·m²), fly ash and dolomite had the best antibacterial properties, removing 100% of bacteria in the first 200 mL of water passed through biosorbent columns and removing bacteria at the third filtration with a count of less than 150 CFU/mL. Dolomite with activated carbon reduced color, odor, and turbidity. Dolomite and fly ash were found to be less expensive than traditional water filtration systems such as ultrafiltration and reverse osmosis, which are commonly used in industrial wastewater treatment. Future pilot-scale research is needed to fully evaluate these preliminary findings. Importantly, this research proposes a novel approach to wastewater treatment with circular economy benefits, recyclability, and a lower carbon footprint for the biosorbent materials evaluated. This lends support to their potential integration into wastewater treatment systems, which would reduce chlorine dosing and improve sustainability.