RESUMEN
Ascending inflammation from the vagina is a major cause of preterm birth. Currently, this condition-especially when uncontrolled-has no effective treatment. Human amniotic fluid stem cells (hAFSCs) are mesenchymal stem cells known to exert potent anti-inflammatory effects in animal models of perinatal diseases, such as periventricular leukomalacia, myelomeningocele, and neonatal sepsis. However, hAFSC therapy for inflammation-induced preterm birth has not been tested. In order to determine the therapeutic effect of hAFSC transplantation, we employed a preterm mouse model of ascending infection; this model was constructed by administering lipopolysaccharide to pregnant mice. We investigated the preterm birth rate and evaluated the inflammation of tissues, which is related to progressive infections, such as those involving the cervix, placenta, and lavage cells, using real-time qPCR. Further, we tracked the fluorescence of fluorescently labeled hAFSCs using an in vivo imaging system, and hAFSC aggregation was evaluated using immunohistochemistry analysis. We also investigated the presence of multiple types of peritoneal macrophages via flow cytometry analysis. Finally, we performed sphere culturing and co-culturing to determine the therapeutic effects of hAFSCs, such as their anti-inflammatory effects and their potential to alter macrophage polarization. We found that hAFSC administration to the peritoneal cavity significantly reduced inflammation-induced preterm birth in the mouse model. The treatment also significantly suppressed inflammation of the placenta and cervix. Transplanted hAFSCs may have aggregated with peritoneal macrophages, switching them from an inflammatory to an anti-inflammatory type. This property has been reported in vivo previously, but here, we examined the effect in vitro. Our findings support the hypothesis that hAFSCs suppress inflammation and reduce preterm birth by switching macrophage polarity. This study is the first to demonstrate that hAFSCs are effective in the treatment and prevention of inflammation-induced preterm birth.
Asunto(s)
Células Madre Mesenquimatosas , Nacimiento Prematuro , Embarazo , Femenino , Humanos , Ratones , Recién Nacido , Animales , Líquido Amniótico , Nacimiento Prematuro/prevención & control , Células Madre , Inflamación/inducido químicamenteRESUMEN
Despite the poor prognosis associated with myelomeningocele (MMC), the options for prenatal treatments are still limited. Recently, fetal cellular therapy has become a new option for treating birth defects, although the therapeutic effects and mechanisms associated with such treatments remain unclear. The use of human amniotic fluid stem cells (hAFSCs) is ideal with respect to immunoreactivity and cell propagation. The prenatal diagnosis of MMC during early stages of pregnancy could allow for the ex vivo proliferation and modulation of autologous hAFSCs for use in utero stem cell therapy. Therefore, we investigated the therapeutic effects and mechanisms of hAFSCs-based treatment for fetal MMC. hAFSCs were isolated as CD117-positive cells from the amniotic fluid of 15- to 17-week pregnant women who underwent amniocentesis for prenatal diagnosis and consented to this study. Rat dams were exposed to retinoic acid to induce fetal MMC and were subsequently injected with hAFSCs in each amniotic cavity. We measured the exposed area of the spinal cord and hepatocyte growth factor (HGF) levels at the lesion. The exposed spinal area of the hAFSC-treated group was significantly smaller than that of the control group. Immunohistochemical analysis demonstrated a reduction in neuronal damage such as neurodegeneration and astrogliosis in the hAFSC-treated group. Additionally, in lesions of the hAFSC-treated group, HGF expression was upregulated and HGF-positive hAFSCs were identified, suggesting that these cells migrated to the lesion and secreted HGF to suppress neuronal damage and induce neurogenesis. Therefore, in utero hAFSC therapy could become a novel strategy for fetal MMC. Stem Cells Translational Medicine 2019;8:1170-1179.