Alterations in MicroRNA and Cytokine Expressions in Placental and Amniotic Tissues of COVID-19 Affected Pregnant Women.

Since 2019, coronavirus disease 2019 (COVID-19) has been associated with increased risks of preterm birth and placental complications. We prospectively investigated alterations in microRNAs (miRNAs) and cytokines in placental and amniotic tissues from pregnant women with and without COVID-19 to evaluate the infection's impact on pregnancy. Placental and amniotic samples were collected at delivery from 15 pregnant women, including 7 with confirmed COVID-19 and 8 healthy controls. Tissue lysates were prepared for miRNA sequencing with QIAseq and cytokine profiling using Bio-Plex ProTM assays, and clinical data were recorded for correlation analyses. We identified three miRNAs, including hsa-miR-20a-5p, hsa-miR-20b-5p, and hsa-miR-25-3p were consistently upregulated in both placental and amniotic tissues following maternal COVID-19 infection. Eight cytokines, including IL-4, IL-9, and IL-10, showed strong correlations with these miRNA changes. Besides, placental hsa-miR-20b-5p expression was positively correlated with IL-9 levels. Although expression of hsa-miR-142-3p and hsa-miR-155-5p did not differ significantly between COVID-19-positive and control groups, these miRNAs demonstrated inverse correlations with IL-4 and IL-10 levels in amniotic samples, suggesting potential immunoregulatory roles during infection. These findings highlight a set of miRNAs with shared regulatory patterns across placental and amniotic compartments and their close association with key cytokines, suggesting common immune mechanisms at the maternal-fetal interface. miRNA-cytokine signatures may serve as candidate biomarkers for monitoring the effects of COVID-19 in prenatal and postnatal care.