Department of Advanced Translational Microbiology, Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Via dell'Istria, 65, 34137 Trieste, Italy.
Unit of Fetal Medicine and Prenatal Diagnosis, Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Via dell'Istria, 65, 34137 Trieste, Italy.
Int J Mol Sci. 2023 Feb 2;24(3):2873. doi: 10.3390/ijms24032873.
The in utero microbiome hypothesis has been long debated. This hypothesis will change our comprehension of the pioneer human microbiome if proved correct. In 60 uncomplicated pregnancies, we profiled the microbiome of chorionic villi (CV) and amniotic fluids (AF) in relation to maternal saliva, rectum, and vagina and the soluble cytokines cascade in the vagina, CV and AF. In our series, 12/37 (32%) AF and 10/23 (44%) CV tested positive for bacterial DNA. CV and AF harbored bacterial DNA of Streptococcus and Lactobacillus, overlapping that of the matched oral and vaginal niches, which showed a dysbiotic microbiome. In these pregnant women, the immune profiling revealed an immune hyporesponsiveness in the vagina and a high intraamniotic concentration of inflammatory cytokines. To understand the eventual role of bacterial colonization of the CV and AF and the associated immune response in the pregnancy outcome, further appropriate studies are needed. In this context, further studies should highlight if the hematogenous route could justify the spread of bacterial DNA from the oral microbiome to the placenta and if vaginal dysbiosis could favor the likelihood of identifying CV and AF positive for bacterial DNA.
子宫内微生物组假说长期以来一直存在争议。如果这一假设被证明是正确的，它将改变我们对人类早期微生物组的理解。在 60 例单纯妊娠中，我们对绒毛膜绒毛（CV）和羊水（AF）的微生物组与母体唾液、直肠和阴道以及阴道、CV 和 AF 中的可溶性细胞因子级联进行了分析。在我们的研究中，12/37（32%）的 AF 和 10/23（44%）的 CV 检测到细菌 DNA 呈阳性。CV 和 AF 携带了链球菌和乳杆菌的细菌 DNA，与口腔和阴道生态位的 DNA 重叠，这表明微生物组存在失调。在这些孕妇中，免疫分析显示阴道免疫反应低下，羊水中炎症细胞因子浓度较高。为了了解 CV 和 AF 细菌定植及其相关免疫反应对妊娠结局的最终作用，还需要进一步的适当研究。在这种情况下，进一步的研究应该强调血液传播途径是否可以解释口腔微生物组中的细菌 DNA 传播到胎盘，以及阴道菌群失调是否会增加 CV 和 AF 检测到细菌 DNA 的可能性。
