Fetal lung underdevelopment, also known as pulmonary hypoplasia, is characterized by decreased lung growth and maturation. The most common birth defect found in babies with pulmonary hypoplasia is congenital diaphragmatic hernia (CDH). Despite research and clinical advances, babies with CDH still have high morbidity and mortality rates, which are directly related to the severity of lung underdevelopment. To date, there is no effective treatment that promotes fetal lung growth and maturation. Here, we describe a stem cell–based approach in rodents that enhances fetal lung development via the administration of extracellular vesicles (EVs) derived from amniotic fluid stem cells (AFSCs). Using fetal rodent models of pulmonary hypoplasia (primary epithelial cells, organoids, explants, and in vivo), we demonstrated that AFSC-EV administration promoted branching morphogenesis and alveolarization, rescued tissue homeostasis, and stimulated epithelial cell and fibroblast differentiation. We confirmed this regenerative ability in in vitro models of lung injury using human material, where human AFSC-EVs obtained following good manufacturing practices restored pulmonary epithelial homeostasis. Investigating EV mechanism of action, we found that AFSC-EV beneficial effects were exerted via the release of RNA cargo. MicroRNAs regulating the expression of genes involved in lung development, such as the miR17–92 cluster and its paralogs, were highly enriched in AFSC-EVs and were increased in AFSC-EV–treated primary lung epithelial cells compared to untreated cells. Our findings suggest that AFSC-EVs hold regenerative ability for underdeveloped fetal lungs, demonstrating potential for therapeutic application in patients with pulmonary hypoplasia.
The purpose of the present study was to determine the ability of lung‐to‐head ratio to predict survival and need for extracorporeal membrane oxygenation support in fetuses with left congenital diaphragmatic hernia without herniation of the liver into the chest. The perinatal records of 20 fetuses with isolated left congenital diaphragmatic hernia without herniation of the left lobe of the liver into the chest were reviewed. Fetuses were stratified into two groups depending on lung‐to‐head ratio: those with a ratio of less than 1.4 (historically a poor prognosis group) and those with a ratio of greater than 1.4. The outcome of both groups was compared with chi‐square analysis. Eight of 11 fetuses with a lung‐to‐head ratio greater than 1.4 survived, whereas 8 of 9 fetuses with a ratio of less than 1.4 survived. No differences were noted in the need for extracorporeal membrane oxygenation support or survival between the two groups. Fetuses with a prenatally diagnosed left congenital diaphragmatic hernia without herniation of liver into the chest have a favorable prognosis even in the presence of a low lung‐to‐head ratio.
Fetal teratomas are the most common tumors diagnosed prenatally. The majority of these tumors are benign and cured by complete resection of the mass during the neonatal period. Prenatal diagnosis has improved the perinatal management of these lesions and especially for the teratomas that might benefit from fetal intervention. A comprehensive prenatal evaluation including conventional ultrasounds, Doppler, echocardiography and fetal MRI, is essential for an effective counseling and perinatal management. Antenatal counseling helps the parents to better understand the natural history, fetal intervention, and perinatal management of these tumors, which differ dramatically depending on their size and location. Fetal surgical debulking improves survival in cases of sacrococcygeal teratoma with cardiac decompensation. Additionally, the use of an EXIT procedure reduces the morbidity and mortality if a complicated delivery in cases of cervical and mediastinal teratomas. Here, we offer an overview of all fetal teratomas and their recommended management, with emphasis on in utero treatment options.
Congenital diaphragmatic hernia (CDH) occurs in approximately 1:2,500 human births and has high morbidity and mortality rates, primarily due to pulmonary hypoplasia and pulmonary hypertension. Tracheal occlusion (TO), in experimental animals, distends lungs and increases lung growth and alveolar type I cell maturation but decreases surfactant components and reduces alveolar type II cell density. We examined effects of CDH and CDH+TO on lung growth and maturation in fetal rats. To induce CDH, we administered nitrofen (100 mg) to dams at 9.5 days of gestation. We compared lungs from fetuses with CDH, CDH+TO, and those exposed to nitrofen without CDH. CDH decreased lung wet weight bilaterally (P < 0.0001) and DNA content in lung ipsilateral to CDH (P < 0.05). CDH+TO significantly increased lung wet weights bilaterally; DNA content was intermediate between CDH and NC. To evaluate effects on the distal pulmonary epithelium, we examined surfactant mRNA and protein levels, type I and II cell-specific markers (RTI(40) and RTII(70), respectively), and transcriptional regulator thyroid transcription factor-1 (TTF-1). Decreased lung distension (due to CDH) increased SP-C mRNA and TTF-1 protein expression and reduced RTI(40) (P < 0.05 for all). Increased lung distension (due to CDH+TO) reduced expression of SP mRNAs and pro-SP-C and TTF-1 proteins and enhanced expression of RTI(40) (mRNA and protein; P < 0.05 for all). We conclude that CDH+TO partially reverses effects of CDH; it corrects the pulmonary hypoplasia and restores type I cell differentiation but adversely affects SP expression in type II cells. These effects may be mediated through changes in TTF-1 expression.
Objective: To report on the initial experience in a single Brazilian university clinic of the use of fetoscopic endotracheal occlusion (FETO) to treat severe isolated congenital diaphragmatic hernia (CDH). Methods: The inclusion criteria for FETO for this prospective study were isolated CDH and intrathoracic herniation of the liver, as well as the lung area to head circumference ratio (LHR) <1.0. The main variables evaluated were LHR and observed to expected (o/e) LHR before and after FETO, gestational age (GA) at FETO, reversal of tracheal occlusion (TO), and birth and discharge of a living child from the hospital. Results: Among 8 isolated left-sided CDH cases with normal karyotypes, the median LHR and o/e LHR before FETO were 0.7 (range: 0.6–0.9) and 0.27 (range: 0.22–0.32), respectively. The median LHR and o/e LHR after FETO were 1.2 (range: 0.9–1.8) and 0.45 (0.31–0.67), respectively. The median GA at FETO, reversal of TO and birth were 26.8 (range: 26–29), 32.5 (range: 31.0–34.0) and 37 weeks (range: 35–37), respectively. Neonatal survival at the time of hospital discharge was 50% (4/8). Conclusion: FETO is feasible at our institution and may help to improve postnatal survival of children with severe CDH in developing countries.
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