Littlefield, Dawn

Withdrawal Statement The authors have withdrawn the manuscript because the data it contained has been updated. Consequently, they request that this work should not be cited as a reference for any projects to ensure the use of the most current information. For any questions or further clarifications, readers are encouraged to contact the corresponding author directly

Abstract Background The worldwide prevalence of cytomegalovirus (CMV) infection is estimated to be 83-100%.1,2 In pregnancy, transmission to the fetus can occur through the placenta with 0.4-2.3% of all newborns affected.3 The phenotype of congenital CMV (cCMV) has a spectrum of severity; 10-20% of exposed neonates show severe clinical manifestations.4 CMV has a wide range of tropism and can infect epithelial, myeloid, and endothelial cells. However, the cellular mechanisms of cCMV infection, and how they influence disease severity in exposed fetuses during gestation are not fully outlined,5 Here, we used the NanoString™ Digital Spatial Profiler (DSP) to characterize the cell-specific proteomic profile in placental tissue from infants with cCMV. Methods Placental tissue from 5 CMV-affected and 4 CMV-unaffected pregnancies were retrieved from the Mayo Clinic tissue repository. Immune cells were identified by CD45 positivity and cytotrophoblasts (CTBs) identified by CK7. The cell-specific proteome of these tissues was identified using the NanoString™ immune cell and cell death panels. Data was analyzed by NanoString™ GeoMx technology. Results Unsupervised clustering illustrated a distinct proteome in the immune cell compartment of CMV-positive compared to CMV-negative placental tissue (Figure 1). Linear Mixed Model (LMM) analysis revealed that immune cell related proteins were significantly overexpressed in CMV+ tissue as were four proteins associated with cell death: BIM, BCLXL, PARP, neurofibromin (Figure 2). Clustering did not demonstrate a distinct proteome in the CTB compartment (Figure 3), but LMM showed that two immune markers (CD44 and HLA-DR) and a cell death protein (BCL6) were overexpressed by CTBs in CMV+ tissue (Figure 4). The proteome of immune cells, and to a lesser extent in CTBs in CMV-infected placentae differs from CMV-uninfected placentae with overexpression of proteins associated with immune activation and cell death. With new screening initiatives set to improve identification of cCMV, our results provide a starting point to identify specific biomarkers and immune pathways associated with disease severity. These biomarkers and pathways may serve as novel antiviral targets in the treatment and management of cCMV. The proteome of immune cells, and to a lesser extent in CTBs in CMV-infected placentae differs from CMV-uninfected placentae with overexpression of proteins associated with immune activation and cell death. With new screening initiatives set to improve identification of cCMV, our results provide a starting point to identify specific biomarkers and immune pathways associated with disease severity. These biomarkers and pathways may serve as novel antiviral targets in the treatment and management of cCMV. Fig 3 - The proteome of immune cells, and to a lesser extent in CTBs in CMV-infected placentae differs from CMV-uninfected placentae with overexpression of proteins associated with immune activation and cell death. With new screening initiatives set to improve identification of cCMV, our results provide a starting point to identify specific biomarkers and immune pathways associated with disease severity. These biomarkers and pathways may serve as novel antiviral targets in the treatment and management of cCMV. Fig 4 - Volcano plot illustrating the differential proteomic expression in CK7+ tissue compartment of CMV-positive placental tissue compared to CMV-negative placental tissue. Conclusion The proteome of immune cells, and to a lesser extent in CTBs in CMV-infected placentae differs from CMV-uninfected placentae with overexpression of proteins associated with immune activation and cell death. With new screening initiatives set to improve identification of cCMV, our results provide a starting point to identify specific biomarkers and immune pathways associated with disease severity. These biomarkers and pathways may serve as novel antiviral targets in the treatment and management of cCMV. Disclosures Mark R. Schleiss, MD, Moderna Vaccines: Grant Support to my Division but no personal honoraria

Abstract Despite intensive characterization of immune responses after COVID-19 infection and vaccination, research examining protective correlates of vertical transmission in pregnancy are limited. Herein, we profiled humoral and cellular characteristics in pregnant women infected or vaccinated at different trimesters and in their corresponding newborns. We noted a significant correlation between spike S1–specific IgG antibody and its RBD-ACE2 blocking activity (receptor-binding domain–human angiotensin-converting enzyme 2) in maternal and cord plasma (P < .001, R > 0.90). Blocking activity of spike S1–specific IgG was significantly higher in pregnant women infected during the third trimester than the first and second trimesters. Elevated levels of 28 cytokines/chemokines, mainly proinflammatory, were noted in maternal plasma with infection at delivery, while cord plasma with maternal infection 2 weeks before delivery exhibited the emergence of anti-inflammatory cytokines. Our data support vertical transmission of protective SARS-CoV-2–specific antibodies. This vertical antibody transmission and the presence of anti-inflammatory cytokines in cord blood may offset adverse outcomes of inflammation in exposed newborns.

In 1989, one in four (25%) infants born to women living with HIV were infected; by the age of 2 years, there was 25% mortality among them due to HIV. These and other pieces of data prompted the development of interventions to offset vertical transmission, including the landmark Pediatric AIDS Clinical Trial Group Study (PACTG 076) in 1994. This study reported a 67.5% reduction in perinatal HIV transmission with prophylactic antenatal, intrapartum, and postnatal zidovudine. Numerous studies since then have provided compelling evidence to further optimize interventions, such that annual transmission rates of 0% are now reported by many health departments in the US and elimination has been validated in several countries around the world. Despite this success, the elimination of HIV’s vertical transmission on the global scale remains a work in progress, limited by socioeconomic factors such as the prohibitive cost of antiretrovirals. Here, we review some of the key trials underpinning the development of guidelines in the US as well as globally, and discuss the evidence through a historic lens.

Abstract Background Despite extensive studies of human immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) vaccination, research examining protective correlates of vertical transmission following maternal exposure in pregnancy remain limited. Here, we characterized antibody and cytokine responses in maternal and cord blood following infection or vaccination at various timepoints during gestation. Methods Spike S1 protein-specific binding antibodies and antibodies capable of blocking the interaction between the receptor binding domain (RBD) and the angiotensin converting enzyme 2 (ACE2) were measured in maternal and cord blood by ELISA. Serum concentrations of 74 cytokines/chemokines were measured by multiplex assay. Humoral responses and cytokine levels from matched maternal and fetal cord sera were compared and examined for potential correlations. Results We observed a highly significant correlation between Spike S1-specific antibody titer and RBD-ACE2 blocking antibody activity between maternal and fetal cord serum (p < 2.2e-16, R > 0.90). Blocking antibody activity was significantly higher for mothers infected during the 3rd trimester compared to earlier trimesters; however, vaccinated mothers developed and transferred higher antibody titers with greater RBD-ACE2 blocking antibody activity to their neonates than infected mothers. Furthermore, vaccine-induced Spike S1 IgG transfer ratios (fetal cord/maternal) were significantly higher than those induced by infection (p = 0.002). Multiplex assay showed significantly elevated levels of 33 cytokines/chemokines, mainly pro-inflammatory in infected maternal serum samples, while the paired fetal cord samples exhibited an anti-inflammatory cytokine predominance. Conclusion Our data support selective vertical transmission of potentially protective humoral responses against SARS-CoV-2, especially following vaccination in the 3rd trimester. The anti-inflammatory cytokine predominance in cord blood that persists despite maternal SARS-CoV-2 infection may offset the adverse outcomes of inflammation in pregnancy for the neonate. Disclosures All Authors: No reported disclosures.

Background: Congenital toxoplasmosis (CT) is a widespread infection in several countries, and it is defined as an infection of a fetus, newborn, or infant under 1 year of age. Moreover, it represents a thread to pregnant women globally. The objective of our study is to evaluate a potential association between prematurity and CT and whether intrauterine transmission impacts gestational length during pregnancy. Methods: PubMed, Cochrane Library and Google Scholar databases were searched from 1950 to 2019. Case–control studies, retrospective, and prospective cohort studies were eligible. Seven studies were included from a total of 314. The Newcastle–Ottawa scale was used to establish the quality of the articles included. Results: Based on our review, an association between CT and preterm labor was not established, which may reflect heterogeneity in screening, treatments administered, and differing reported incidences of CT across continents over 69 years. A multicenter prospective cohort study powered to investigate a potential association is indicated. Conclusion: Further studies are needed including multicenter prospective cohort studies powered to investigate key clinical associations such as vertical transmission and preterm birth.