Search

Background: Congenital and postnatal cytomegalovirus (CMV) infections in Uganda is prevalent and may compromise the health of Ugandan children. The objective of this study is to estimate the prevalence of CMV infections in newborns, neonates with sepsis, and infants with hydrocephalus in Uganda. Methods: Three populations: (1) newborn-mother pairs, (2) neonates with sepsis, and (3) infants (≤ 3 months) with non-postinfectious (NPIH) or postinfectious (PIH) hydrocephalus, were evaluated over four years (2016-2019) for CMV infection at three medical centers – two in the Eastern (Mbale) and one in Western (Mbarara) Uganda. To characterize the prevalence of CMV we used quantitative PCR (qPCR) analysis. In newborn-mother pairs maternal blood (n=99) and a subset of matching cord blood (n=92), placental tissue (n=99), and vaginal specimens (n=99) were tested for CMV. In neonates and infants aged 3 months or less, peripheral blood (751 with sepsis, 399 with hydrocephalus) and cerebrospinal fluid samples (560 with sepsis, 399 with hydrocephalus (205 PIH, 194 NPIH) were also tested for CMV. Findings: The overall CMV prevalence across all groups was 9%. In newborn-mother pairs, a 3% (n=3/92; 95% CI, 1-9%) prevalence of cord blood positivity and 33% (n=33/99; 95% CI, 24-44%) prevalence of maternal vaginal shedding of CMV was estimated. In neonates with clinical sepsis, a 2% (n=17/751; 95% CI, 1-4%) CMV prevalence was estimated. Maternal HIV seropositivity (adjusted odds ratio [aOR], 21.09; 95% CI, 4-109; p= 0.0002), residence in Eastern Uganda (aOR, 11.10; 95% CI, 3-77; p=0 .003), maternal age < 25 years (aOR, 4.91; 95% CI, 2-20; p=0.012), and older neonatal age (9 days vs. 5 days; p= 0.006) were associated with CMV in neonates with clinical sepsis. In infants with PIH, the prevalence in blood was 24% (n=50/205; 95% CI, 19-31%) and in infants with NPIH it was 20% (n=39/194; 95% CI, 15-26%; p=0.34). CMV was present in the CSF of 13% (n=26/205; 95% CI, 8-18%) of infants with PIH compared to 0.5% of infants with NPIH (n=1/194; 95% CI, 0-3%, p

Summary: Inflammation during neonatal brain infections leads to significant secondary sequelae such as hydrocephalus, which often follows neonatal sepsis in the developing world. In 100 African hydrocephalic infants we identified the biological pathways that account for this response. The dominant bacterial pathogen was a Paenibacillus species, with frequent cytomegalovirus co-infection. A proteogenomic strategy was employed to confirm host immune response to Paenibacillus and to define the interplay within the host immune response network. Immune activation emphasized neuroinflammation, oxidative stress reaction, and extracellular matrix organization. The innate immune system response included neutrophil activity, signaling via IL-4, IL-12, IL-13, interferon, and Jak/STAT pathways. Platelet-activating factors and factors involved with microbe recognition such as Class I MHC antigen-presenting complex were also increased. Evidence suggests that dysregulated neuroinflammation propagates inflammatory hydrocephalus, and these pathways are potential targets for adjunctive treatments to reduce the hazards of neuroinflammation and risk of hydrocephalus following neonatal sepsis.

SummaryPrecise regulation of the formation, maintenance, and remodeling of the vasculature is required for normal development, tissue response to injury, and tumor progression. How specific microRNAs intersect with and modulate angiogenic signaling cascades is unknown. Here, we identified microRNAs that were enriched in endothelial cells derived from mouse embryonic stem (ES) cells and in developing mouse embryos. We found that miR-126 regulated the response of endothelial cells to VEGF. Additionally, knockdown of miR-126 in zebrafish resulted in loss of vascular integrity and hemorrhage during embryonic development. miR-126 functioned in part by directly repressing negative regulators of the VEGF pathway, including the Sprouty-related protein SPRED1 and phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2/p85-β). Increased expression of Spred1 or inhibition of VEGF signaling in zebrafish resulted in defects similar to miR-126 knockdown. These findings illustrate that a single miRNA can regulate vascular integrity and angiogenesis, providing a new target for modulating vascular formation and function.