Reduced control of SARS-CoV-2 infection associates with lower mucosal antibody responses in pregnancy.

Pregnant patients are at greater risk of hospitalization with severe COVID-19 than non-pregnant people. This was a retrospective observational cohort study of remnant clinical specimens from patients who visited acute care hospitals within the Johns Hopkins Health System in the Baltimore, MD-Washington DC, area between October 2020 and May 2022. Participants included confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected pregnant people and matched non-pregnant people (the matching criteria included age, race/ethnicity, area deprivation index, insurance status, and vaccination status to ensure matched demographics). The primary dependent measures were clinical COVID-19 outcomes, infectious virus recovery, viral RNA levels, and mucosal anti-spike (S) IgG titers from upper respiratory tract samples. A total of 452 individuals (117 pregnant and 335 non-pregnant) were included in the study, with both vaccinated and unvaccinated individuals represented. Pregnant patients were at increased risk of hospitalization (odds ratio [OR] = 4.2; confidence interval [CI] = 2.0-8.6), intensive care unit admittance (OR = 4.5; CI = 1.2-14.2), and being placed on supplemental oxygen therapy (OR = 3.1; CI = 1.3-6.9). Individuals infected during their third trimester had higher mucosal anti-S IgG titers and lower viral RNA levels (P < 0.05) than those infected during their first or second trimesters. Pregnant individuals experiencing breakthrough infections due to the Omicron variant had reduced anti-S IgG compared to non-pregnant patients (P < 0.05). The observed increased severity of COVID-19 and reduced mucosal antibody responses particularly among pregnant participants infected with the Omicron variant suggest that maintaining high levels of SARS-CoV-2 immunity through booster vaccines may be important for the protection of this at-risk population.IMPORTANCEIn this retrospective observational cohort study, we analyzed remnant clinical samples from non-pregnant and pregnant individuals with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections who visited the Johns Hopkins Hospital System between October 2020 and May 2022. Disease severity, including intensive care unit admission, was greater among pregnant than non-pregnant patients. Vaccination reduced recovery of infectious virus and viral RNA levels in non-pregnant patients, but not in pregnant patients. In pregnant patients, increased nasopharyngeal viral RNA levels and recovery of infectious virus were associated with reduced mucosal IgG antibody responses, especially among women in their first trimester of pregnancy or experiencing breakthrough infections from Omicron variants. Taken together, this study provides insights into how pregnant patients are at greater risk of severe COVID-19. The novelty of this study is that it focuses on the relationship between the mucosal antibody response and its association with virus load and disease outcomes in pregnant people, whereas previous studies have focused on serological immunity. Vaccination status, gestational age, and SARS-CoV-2 omicron variant impact mucosal antibody responses and recovery of infectious virus from pregnant patients.

Fetal growth restriction exhibits various mTOR signaling in different regions of mouse placentas with altered lipid metabolism.

Fetal growth restriction (FGR) is a common complication of pregnancy and can have significant impact on obstetric and neonatal outcomes. Increasing evidence has shown that the inhibited mechanistic target of rapamycin (mTOR) signaling in placenta is associated with FGR. However, interpretation of existing research is limited due to inconsistent methodologies and varying understanding of the mechanism by which mTOR activity contributes to FGR. Hereby, we have demonstrated that different anatomic regions of human and mouse placentas exhibited different levels of mTOR activity in normal compared to FGR pregnancies. When using the rapamycin-induced FGR mouse model, we found that placentas of FGR pregnancies exhibited abnormal morphological changes and reduced mTOR activity in the decidual-junctional layer. Using transcriptomics and lipidomics, we revealed that lipid and energy metabolism was significantly disrupted in the placentas of FGR mice. Finally, we demonstrated that maternal physical exercise during gestation in our FGR mouse model was associated with increased fetal and placental weight as well as increased placental mTOR activity and lipid metabolism. Collectively, our data indicate that the inhibited placental mTOR signaling contributes to FGR with altered lipid metabolism in mouse placentas, and maternal exercise could be an effective method to reduce the occurrence of FGR or alleviate the adverse outcomes associated with FGR.

Membrane inflammasome activation by choriodecidual Ureaplasma parvum infection without intra-amniotic infection in a Non-Human Primate model†.

Intrauterine infection is a significant cause of neonatal morbidity and mortality. Ureaplasma parvum is a microorganism commonly isolated from cases of preterm birth and preterm premature rupture of membranes (pPROM). However, the mechanisms of early stage ascending reproductive tract infection remain poorly understood. To examine inflammation in fetal (chorioamnionic) membranes we utilized a non-human primate (NHP) model of choriodecidual U. parvum infection. Eight chronically catheterized pregnant rhesus macaques underwent maternal-fetal catheterization surgery at ~105-112 days gestation and choriodecidual inoculation with U. parvum (105 CFU/mL, n =4) or sterile media (controls; n = 4) starting at 115-119 days, repeated at 5-day intervals until C-section at 136-140 days (term=167 days). The average inoculation to delivery interval was 21 days, and Ureaplasma infection of the amniotic fluid (AF) was undetectable in all animals. Choriodecidual Ureaplasma infection resulted in increased fetal membrane expression of MMP-9 and PTGS2, but did not result in preterm labor or increased concentrations of AF pro-inflammatory cytokines. However, membrane expression of inflammasome sensors, NLRP3, NLRC4, AIM2, and NOD2, and adaptor ASC (PYCARD) gene expression were significantly increased. Gene expression of IL-1ß, IL-18, IL-18R1  , CASPASE-1, and pro-CASPASE-1 protein increased with Ureaplasma infection. Downstream inflammatory genes MYD88 and NFκB (Nuclear factor kappa-light-chain-enhancer of activated B cells) were also significantly upregulated. These results demonstrate that choriodecidual Ureaplasma infection, can cause activation of inflammasome complexes and pathways associated with pPROM and preterm labor prior to microbes being detectable in the AF.

Suppression of progesterone by influenza A virus mediates adverse maternal and fetal outcomes in mice.

Influenza A virus infection during pregnancy can cause adverse maternal and fetal outcomes but the mechanism responsible remains elusive. Infection of outbred mice with 2009 H1N1 at embryonic day (E) 10 resulted in significant maternal morbidity, placental tissue damage and inflammation, fetal growth restriction, and developmental delays that lasted through weaning. Restriction of pulmonary virus replication was not inhibited during pregnancy, but infected dams had suppressed circulating and placental progesterone (P4) concentrations that were caused by H1N1-induced upregulation of pulmonary cyclooxygenase (COX)-1-, but not COX-2-, dependent synthesis and secretion of prostaglandin (PG) F2α. Treatment with 17-α-hydroxyprogesterone caproate (17-OHPC), a synthetic progestin that is safe to use in pregnancy, ameliorated the adverse maternal and fetal outcomes from H1N1 infection and prevented placental cell death and inflammation. These findings highlight the therapeutic potential of progestin treatments for influenza during pregnancy.IMPORTANCEPregnant individuals are at risk of severe outcomes from both seasonal and pandemic influenza A viruses. Influenza infection during pregnancy is associated with adverse fetal outcomes at birth and adverse consequences for offspring into adulthood. When outbred dams, with semi-allogenic fetuses, were infected with 2009 H1N1, in addition to pulmonary virus replication, lung damage, and inflammation, the placenta showed evidence of transient cell death and inflammation that was mediated by increased activity along the arachidonic acid pathway leading to suppression of circulating progesterone. Placental damage and suppressed progesterone were associated with detrimental effects on perinatal growth and developmental delays in offspring. Treatment of H1N1-infected pregnant mice with 17-OHPC, a synthetic progestin treatment that is safe to use in pregnancy, prevented placental damage and inflammation and adverse fetal outcomes. This novel therapeutic option for the treatment of influenza during pregnancy should be explored clinically.

Membrane Inflammasome Activation by Choriodecidual Ureaplasma parvum Infection without Intra-Amniotic Infection in an NHP Model.

Intrauterine infection is a significant cause of preterm labor and neonatal morbidity and mortality. Ureaplasma parvum is the micro-organism most commonly isolated from cases of preterm birth and preterm premature rupture of membranes (pPROM). However, the mechanisms during the early stages of ascending reproductive tract infection that initiate maternal-fetal inflammatory pathways, preterm birth and pPROM remain poorly understood. To examine inflammation in fetal (chorioamnionic) membranes in response to Ureaplasma parvum infection, we utilized a novel in vivo non-human primate model of early choriodecidual infection. Eight chronically catheterized pregnant rhesus macaques underwent maternal-fetal catheterization surgery at 105-112 days gestation and choriodecidual inoculation with Ureaplasma parvum (10 5 cfu/mL of a low passaged clinical isolate, serovar 1; n=4) or saline/sterile media (Controls; n=4) starting at 115-119 days gestation, repeated every 5 days until scheduled cesarean-section at 136-140d gestation (term=167d). The average inoculation to delivery interval was 21 days and Ureaplasma infection of the amniotic fluid was undetectable by culture and PCR in all animals. Inflammatory mediators in amniotic fluid (AF) were assessed by Luminex, ELISA and multiplex assays. RNA was extracted from the chorion and amnionic membranes for single gene analysis (qRT-PCR) and protein expression was determined by Western blot and immunohistochemistry. Our NHP model of choriodecidual Ureaplasma infection, representing an early-stage ascending reproductive tract infection without microbial invasion of the amniotic cavity, resulted in increased fetal membrane protein and gene expression of MMP-9 and PTGS2, but did not result in preterm labor (no increase in uterine contractility) or increased concentrations of amniotic fluid pro-inflammatory cytokines (IL-1ß, IL-6, IL-8, IL-18, TNF-α). However, membrane expression of inflammasome sensor molecules, NLRP3, NLRC4, AIM2 and NOD2, and the adaptor protein ASC ( PYCARD ) gene expression were significantly increased in the Ureaplasma group when compared to non-infected controls. Gene expression of IL-1 ß, IL-18, the IL-18R1 receptor , CASPASE-1 and pro-CASPASE-1 protein were also increased in the fetal membranes with Ureaplasma infection. Downstream inflammatory signaling genes MYD88 was also significantly upregulated in both the amnion and chorion, along with a significant increase in NFKB in the chorion. These results demonstrate that even at the early stages of ascending reproductive tract Ureaplasma infection, activation of inflammasome complexes and pathways associated with degradation of chorioamnionic membrane integrity are present. This study therefore provides experimental evidence for the importance of the early stages of ascending Ureaplasma infection in initiating processes of pPROM and preterm labor. These findings have implications for the identification of intrauterine inflammation before microbes are detectable in the amniotic fluid (sterile inflammation) and the timing of potential treatments for preterm labor and fetal injury caused by intrauterine infection.

Addressing the smoking-hypertension paradox in pregnancy: insight from a multiethnic US birth cohort.

Background: Smoking during pregnancy has been associated with reduced risk of a spectrum of hypertensive (HTN) disorders, known as the "smoking-hypertension paradox." Objective: We sought to test potential epidemiologic explanations for the smoking-hypertension paradox. Methods: We analyzed 8510 pregnant people in the Boston Birth Cohort, including 4027 non-Hispanic Black and 2428 Hispanic pregnancies. Study participants self-reported tobacco, alcohol, cannabis, opioids, or cocaine use during pregnancy. We used logistic regression to assess effect modification by race/ethnicity, and confounding of concurrent substances on hypertensive disorders or prior pregnancy. We also investigated early gestational age as a collider or competing risk for pre-eclampsia, using cause-specific Cox models and Fine-Gray models, respectively. Results: We replicated the paradox showing smoking to be protective against hypertensive disorders among Black participants who used other substances as well (aOR: 0.61, 95% CI: 0.41, 0.93), but observed null effects for Hispanic participants (aOR: 1.14, 95% CI: 0.55, 2.36). In our cause-specific Cox regression, the effects of tobacco use were reduced to null effects with pre-eclampsia (aOR: 0.81, 95% CI: 0.63, 1.04) after stratifying for preterm birth. For the Fine-Gray competing risk analysis, the paradoxical associations remained. The smoking paradox was either not observed or reversed after accounting for race/ethnicity, other substance use, and collider-stratification due to preterm birth. Conclusions: These findings offer new insights into this paradox and underscore the importance of considering multiple sources of bias in assessing the smoking-hypertension association in pregnancy.

Suppression of progesterone by influenza A virus mediates adverse maternal and fetal outcomes in mice.

Influenza A virus infection during pregnancy can cause adverse maternal and fetal outcomes, but the mechanism responsible remains elusive. Infection of outbred mice with 2009 H1N1 at embryonic day (E) 10 resulted in significant maternal morbidity, placental tissue damage and inflammation, fetal growth restriction, and developmental delays that lasted through weaning. Restriction of pulmonary virus replication was not inhibited during pregnancy, but infected dams had suppressed circulating and placental progesterone (P4) concentrations that were caused by H1N1-induced upregulation of pulmonary cyclooxygenase (COX)-1, but not COX-2-, dependent synthesis and secretion of prostaglandin (PG) F2α. Treatment with 17-α-hydroxyprogesterone caproate (17-OHPC), a synthetic progestin that is safe to use in pregnancy, ameliorated the adverse maternal and fetal outcomes from H1N1 infection and prevented placental cell death and inflammation. These findings highlight the therapeutic potential of progestin treatments for influenza during pregnancy.

Adverse outcomes in SARS-CoV-2-infected pregnant mice are gestational age-dependent and resolve with antiviral treatment.

SARS-CoV-2 infection during pregnancy is associated with severe COVID-19 and adverse fetal outcomes, but the underlying mechanisms remain poorly understood. Moreover, clinical studies assessing therapeutics against SARS-CoV-2 in pregnancy are limited. To address these gaps, we developed a mouse model of SARS-CoV-2 infection during pregnancy. Outbred CD1 mice were infected at E6, E10, or E16 with a mouse-adapted SARS-CoV-2 (maSCV2) virus. Outcomes were gestational age-dependent, with greater morbidity, reduced antiviral immunity, greater viral titers, and impaired fetal growth and neurodevelopment occurring with infection at E16 (third trimester equivalent) than with infection at either E6 (first trimester equivalent) or E10 (second trimester equivalent). To assess the efficacy of ritonavir-boosted nirmatrelvir, which is recommended for individuals who are pregnant with COVID-19, we treated E16-infected dams with mouse-equivalent doses of nirmatrelvir and ritonavir. Treatment reduced pulmonary viral titers, decreased maternal morbidity, and prevented offspring growth restriction and neurodevelopmental impairments. Our results highlight that severe COVID-19 during pregnancy and fetal growth restriction is associated with heightened virus replication in maternal lungs. Ritonavir-boosted nirmatrelvir mitigated maternal morbidity along with fetal growth and neurodevelopment restriction after SARS-CoV-2 infection. These findings prompt the need for further consideration of pregnancy in preclinical and clinical studies of therapeutics against viral infections.

Modeling of vertical transmission and pathogenesis of cytomegalovirus in pregnancy: Opportunities and challenges.

In addition to facilitating nutrient, oxygen, and waste transfer between developing fetus and mother, the placenta provides important immune barrier function against infection. Elucidation of the complexity of placental barrier function at the maternal-fetal interface has been greatly aided through experimental model organism systems. In this review, we focus on models of vertical transmission of cytomegalovirus (CMV), a ubiquitous double-stranded DNA viruses whose vertical transmission during pregnancy can lead to devastating neurological and obstetric sequelae. We review the current evidence related to guinea pig and murine models of congenital CMV infection, discuss the possible translatability of a non-human primate model, and conclude with recently developed technology using human placental organoids.

Reduced control of SARS-CoV-2 infection is associated with lower mucosal antibody responses in pregnant women.

Importance: Pregnant women are at increased risk of severe COVID-19, but the contribution of viral RNA load, the presence of infectious virus, and mucosal antibody responses remain understudied. Objective: To evaluate the association of COVID-19 outcomes following confirmed infection with vaccination status, mucosal antibody responses, infectious virus recovery and viral RNA levels in pregnant compared with non-pregnant women. Design: A retrospective observational cohort study of remnant clinical specimens from SARS-CoV-2 infected patients between October 2020-May 2022. Setting: Five acute care hospitals within the Johns Hopkins Health System (JHHS) in the Baltimore, MD-Washington, DC area. Participants: Participants included confirmed SARS-CoV-2 infected pregnant women and matched non-pregnant women (matching criteria included age, race/ethnicity, and vaccination status). Exposure: SARS-CoV-2 infection, with documentation of SARS-CoV-2 mRNA vaccination. Main Outcomes: The primary dependent measures were clinical COVID-19 outcomes, infectious virus recovery, viral RNA levels, and mucosal anti-spike (S) IgG titers from upper respiratory tract samples. Clinical outcomes were compared using odds ratios (OR), and measures of virus and antibody were compared using either Fisher's exact test, two-way ANOVA, or regression analyses. Results were stratified according to pregnancy, vaccination status, maternal age, trimester of pregnancy, and infecting SARS-CoV-2 variant. Resultss: A total of 452 individuals (117 pregnant and 335 non-pregnant) were included in the study, with both vaccinated and unvaccinated individuals represented. Pregnant women were at increased risk of hospitalization (OR = 4.2; CI = 2.0-8.6), ICU admittance, (OR = 4.5; CI = 1.2-14.2), and of being placed on supplemental oxygen therapy (OR = 3.1; CI =13-6.9). An age-associated decrease in anti-S IgG titer and corresponding increase in viral RNA levels (P< 0.001) was observed in vaccinated pregnant, but not non-pregnant, women. Individuals in their 3rd trimester had higher anti-S IgG titers and lower viral RNA levels (P< 0.05) than those in their 1st or 2nd trimesters. Pregnant individuals experiencing breakthrough infections due to the omicron variant had reduced anti-S IgG compared to non-pregnant women (P< 0.05). Conclusions and Relevance: In this cohort study, vaccination status, maternal age, trimester of pregnancy, and infecting SARS-CoV-2 variant were each identified as drivers of differences in mucosal anti-S IgG responses in pregnant compared with non-pregnant women. Observed increased severity of COVID-19 and reduced mucosal antibody responses particularly among pregnant participants infected with the Omicron variant suggest that maintaining high levels of SARS-CoV-2 immunity may be important for protection of this at-risk population.

Adverse outcomes in SARS-CoV-2 infected pregnant mice are gestational age-dependent and resolve with antiviral treatment.

SARS-CoV-2 infection during pregnancy is associated with severe COVID-19 and adverse fetal outcomes, but the underlying mechanisms remain poorly understood. Moreover, clinical studies assessing therapeutics against SARS-CoV-2 in pregnancy are limited. To address these gaps, we developed a mouse model of SARS-CoV-2 infection during pregnancy. Outbred CD1 mice were infected at embryonic day (E) 6, E10, or E16 with a mouse adapted SARS-CoV-2 (maSCV2) virus. Outcomes were gestational age-dependent, with greater morbidity, reduced anti-viral immunity, greater viral titers, and more adverse fetal outcomes occurring with infection at E16 (3rd trimester-equivalent) than with infection at either E6 (1st trimester-equivalent) or E10 (2nd trimester-equivalent). To assess the efficacy of ritonavir-boosted nirmatrelvir (recommended for pregnant individuals with COVID-19), we treated E16-infected dams with mouse equivalent doses of nirmatrelvir and ritonavir. Treatment reduced pulmonary viral titers, decreased maternal morbidity, and prevented adverse offspring outcomes. Our results highlight that severe COVID-19 during pregnancy and adverse fetal outcomes are associated with heightened virus replication in maternal lungs. Ritonavir-boosted nirmatrelvir mitigated adverse maternal and fetal outcomes of SARS-CoV-2 infection. These findings prompt the need for further consideration of pregnancy in preclinical and clinical studies of therapeutics against viral infections.

The role of proprotein convertase subtillisin/kexin type 9 in placental salvage and lipid metabolism in women with preeclampsia.

INTRODUCTION: Preeclampsia is associated with decreased maternal low-density lipoprotein cholesterol (LDL-c), which is essential for fetal growth. The underlying mechanisms for decreased LDL-c in preeclampsia remain unknown. Proprotein convertase subtillisin/kexin type 9 (PCSK9) regulates serum LDL-c via LDL receptor (LDL-R) degradation. We describe the possible role of PCSK9 in lipid metabolism in all compartments of the parturient (maternal blood, placental tissue, and fetal blood) in pregnancies with and without preeclampsia. METHODS: This is an observational study examining PCSK9 levels in maternal sera, umbilical cord blood, and PCSK9 protein content in placental tissue in three different locations (maternal placental interface, fetal placental interface, and umbilical cord) in women with and without preeclampsia at >23 weeks gestation. RESULTS: 68 parturients with preeclampsia and 55 without preeclampsia were enrolled. Maternal serum LDL-c (116.6 ± 48.9 mg/dL vs 146.1 ± 47.1 mg/dL, p = 0.0045) and PCSK9 (83 [61.8127.6] ng/mL vs 105.3 [83.5142.9] ng/mL, p = 0.011) were also reduced in the preeclamptics versus controls. There were no differences in PCSK9 protein content between preeclamptics and controls at comparative placental interfaces. However, PCSK9 protein content increased between the preeclampsia maternal placental interface (1.87 ± 0.62) and the preeclampsia umbilical cord (2.67 ± 1.08, p = 0.0243). DISCUSSION: PCSK9 levels are lower in maternal sera in preeclampsia when compared to controls. Placental PCSK9 protein content in preeclampsia increases from the maternal interface to the umbilical cord; however, this is not seen in controls. This suggests a potential compensatory mechanism for PCSK9 which allows for higher circulating fetal LDL-c levels in preeclampsia.

Markers of intestinal immune activation and inflammation are not associated with preterm birth among women with low level HIV viremia.

BACKGROUND: Maternal markers of intestinal immune activation may be used to predict preterm birth (PTB) in pregnant women living with HIV. METHODS: This study used de-identified samples from the International Maternal Pediatric Adolescent AIDS Clinical Trials Group (IMPAACT) Protocol P1025 study. Singleton pregnancies with ≥3 ml plasma available and HIV viral load ≤400 copies/ml within 4 weeks of specimen collection were included. Frequency matching of PTB cases and term birth controls was performed on basis of maternal race, number of available plasma specimens, and timing of plasma sample collection in a 1:1 ratio. Plasma progesterone, 25-hydroxy vitamin D, soluble CD14, intestinal fatty acid binding protein (I-FABP), Lipopolysaccharide (LPS)-binding protein, and inflammatory cytokines (IL-1B, IFN-gamma, IL-6, TNF-alpha) were measured. Generalized mixed linear regression modeling was used to examine the association between PTB and biomarkers, adjusting for covariates and confounders. Data analyses were performed using SAS 9.4 (Cary, NC). RESULTS: We included 104 PTB compared to 104 controls. Third trimester log2 IL-1B was lower among PTB versus term birth controls by univariate analysis (-1.50 ± 2.26 vs. -.24 ± 2.69, p = .01) though this association was no longer significant by regression modeling. In an uncontrolled, exploratory sub-analysis, subjects with prior PTB had increased odds of PTB with higher I-FABP [aOR 2.72, 95% CI 1.18-6.24] and lower IFN-gamma [aOR .23, 95% CI .12-.41] after adjustment for covariates and confounders. CONCLUSIONS: Intestinal immune activation measured by soluble CD14 or intestinal fatty acid binding protein was not associated with preterm birth among pregnant women with low-level HIV viremia.

Sex-specific differences in T-cell immune dysregulation and aberrant response to inflammatory stimuli in offspring exposed to maternal chronic inflammation.

PROBLEMS: Maternal chronic inflammation (MI) can adversely affect offspring's immune development resulting in dysregulation of splenic T cells. Interleukin 1 beta (IL-1ß) contributes to mediating inflammation in the placenta to induce fetal toxicity and cause long-term postnatal sequelae. In this study, we investigated how MI affects the T-cell immune development from the fetal to the neonatal period and how offspring responded to postnatal IL-1ß challenge when exposed to an adverse intrauterine environment. We also extend these studies to examine the sex-specific differences. METHODS OF STUDY: Time-pregnant CD1 dams were administrated with four consecutive injections of mouse recombinant Interleukin-1ß (rIL-1ß) or phosphate-buffered saline (PBS) from embryonic day (E)14 to E17. Pups were treated with rIL-1ß or PBS at postnatal day (PND)11 (pre-weaning) or PND24 (post-weaning). Pups' splenic immune cells were isolated and then characterized using flow cytometry. RESULTS: At PND12, no differences were observed either in Ctrl or MI offspring. At PND25, we observed elevated amount of CD8+ T cells, descending CD4+ /CD8+ and Treg/Teff ratio in MI offspring. Pre-weaning rIL-1ß administration did not affect T-cell subpopulation in Ctrl pups while post-weaning rIL-1ß administration increased T cells and CD8+ T cells and decreased CD4+ /CD8+ and Treg/Teff ratio in Ctrl offspring. Furthermore, pre-weaning rIL-1ß administration decreased the frequency of T cells and Treg/Teff ratio in MI pups while post-weaning rIL-1ß administration increased Tregs and Treg/Teff in MI pups. Regarding sex-specific changes, we observed that at PND12, MI females exhibited higher CD4+ /CD8+ and Treg/Teff ratio than Ctrl females. At PND25, we observed elevated amount of CD8+ T cells, descending CD4+ /CD8+ and Treg/Teff ratio in MI Females, while MI males did not show any changes in T-cell population. Pre-weaning rIL-1ß administration decreased T-cell frequency in both MI males and females and decreased Treg/Teff ratio only in MI females. Post-weaning rIL-1ß administration increased Tregs and Treg/Teff ratio, and decreased CD4+ /CD8+ ratio in MI females. CONCLUSIONS: Prenatal-inflammation-exposed offspring exhibited dysfunctional T-cell immunity and regulatory immune responses to postnatal challenges, showing both sex-specific and age-dependent differences. It could be speculated from our results that experiencing environmental challenges or adverse stimuli during the vulnerable intrauterine period, such as maternal chronic inflammation, stress, preterm birth, and chronic infections, might induce fetal immune reprogramming and potentially cause long-term adverse immune consequences, such as a predisposition to allergic diseases, autoimmune diseases, asthma and pediatric mortality of unknown etiology.

Estrogen receptor 1 appears essential for fetal viability in a murine model of premature birth.

PROBLEM: Protective effects for adult neurological disorders have been attributed to sex hormones. Using a murine model of prematurity, we evaluated the role of estrogen signaling in the process of perinatal brain injury following exposure to intrauterine inflammation. METHOD OF STUDY: Intrauterine lipopolysaccharide (LPS) was used to invoke preterm labor and fetal neuroinflammation. Fetal brains were analyzed for changes in Esr1, Esr2 and Cyp19. Dams heterozygous for the Esr1 knockout allele were also given intrauterine LPS to compare delivery and offspring viability to wild type controls. RESULTS: The upregulation in inflammatory cytokines was accompanied by an increase in Esr1 and Esr2 transcripts, though protein levels declined. Cyp19 did not differ by mRNA or protein abundance. Offspring from Esr1 mutants were larger, had a longer gestation and significantly greater mortality. CONCLUSIONS: Estrogen signaling is altered in the fetal brains of preterm offspring exposed to neuroinflammatory injury. The reduction of Esr1 and Esr2 proteins with LPS suggests that these proteins are degraded. It is possible that transcriptional upregulation of Esr1 and Esr2 occurs to compensate for the loss of these proteins. Alternatively, the translation of Esr1 and Esr2 mRNAs may be disrupted with LPS while a feedback mechanism upregulates transcription. Intact Esr1 signaling is also associated with early preterm delivery following exposure to intrauterine LPS. A loss of one Esr1 allele delays this process, but appears to do so at the cost of fetal viability. These results suggest estrogen signaling plays opposing roles between maternal and fetal responses to preterm birth.

Temporal Trend of COVID-19 Clinical Severity and the Ethnic/Racial Disparity: A Report from the Maryland Study Group.

OBJECTIVES: This study aimed to evaluate the temporal trend of novel coronavirus disease 2019 (COVID-19) symptoms and severity of clinical outcomes among pregnant women over a calendar year in the State of Maryland and compare clinical outcomes between different ethnic and racial groups. STUDY DESIGN: We conducted a retrospective, multicenter observational study of the temporal trend of COVID-19 clinical presentation during pregnancy in the State of Maryland. We reviewed consecutive charts of adult pregnant females, aged 18 to 55 years, with laboratory-confirmed severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection between March 1, 2020, and February 28, 2021, and managed within the University of Maryland Medical System and Johns Hopkins Medicine. We excluded cases with insufficient data for assessing the COVID-19 diagnosis, pregnancy status, or clinical outcomes. We evaluated the evolution of COVID-19 symptoms at the time of presentation. Also, we compared COVID-19 infection rate, hospitalization rate, oxygen use, and intensive care unit (ICU) admission rates between different ethnic and racial groups. RESULTS: We included 595 pregnant women with laboratory-confirmed COVID-19 over the study period. The prevalence of respiratory and systemic symptoms decreased over time with incidence rate ratios (IRRs) of 0.91 per month (95% confidence interval [CI]: 0.88-0.95) and 0.87 per month (95% CI: 0.83-0.95), respectively. The prevalence of hospitalization, O2 requirement, and ICU admission decreased over time with IRRs of 0.86 per month (95% CI: 0.82-0.91), 0.91 per month (95% CI: 0.84-0.98), and 0.70 per month (95% CI: 0.57-0.85), respectively. The Hispanic and Black populations had a higher COVID-19 infection rate and hospitalization rate than the non-Hispanic White population (p = 0.004, < 0.001, and < 0.001, respectively). CONCLUSION: Understanding the concepts of viral evolution could potentially help the fight against pandemics like COVID-19. Moreover, this might improve the knowledge of how pandemics affect disadvantaged populations and help close the gap in health care inequities. KEY POINTS: · A trade-off between virulence and transmissibility is determined by the natural selection of viruses.. · Understanding the concepts of viral evolution can help the fight against pandemics like COVID-19.. · Evolution of SARS-CoV-2 over time resulted in decreased virulence and increased infectivity..

Effects of fetal haemoglobin on systemic oxygenation in preterm infants and the development of retinopathy of prematurity PacIFiHER Report No. 2.

BACKGROUND/AIMS: Fetal haemoglobin (HbF) has an oxyhaemoglobin dissociation curve that may affect systemic oxygenation and the development of retinopathy of prematurity (ROP). The study aim is to characterise the effects of HbF levels on systemic oxygenation and ROP development. METHODS: Prospective study conducted from 1 September 2017 through 31 December 2018 at the Johns Hopkins NICU. Preterm infants with HbF measured at birth, 31, 34 and 37 weeks post-menstrual age (PMA), complete blood gas and SpO2 recorded up to 42 weeks PMA, and at least one ROP exam were included. RESULTS: Sixty-four preterm infants were enrolled. Higher HbF was associated with significantly higher SpO2, lower PCO2, lower FiO2 from birth to 31 weeks PMA and 31 to 34 weeks PMA (rs=0.51, rs=-0.62 and rs=-0.63; p<0.0001 and rs=0.71, rs=-0.58 and rs=-0.79; p<0.0001, respectively). To maintain oxygen saturation goals set by the neonatal intensive care unit, higher median FiO2 was required for HbF in the lowest tercile from birth compared with HbF in the highest tercile to 31 weeks and 31 to 34 weeks PMA; FiO2=35 (21-100) versus 21 (21-30) p<0.006 and FiO2=30 (28-100) versus 21 (21-30) p<0.001, respectively. Preterm infants with ROP had poorer indices of systemic oxygenation, as measured by median levels of SpO2 and PCO2, and lower levels of HbF (p<0.039 and p<0.0001, respectively) up to 34 weeks PMA. CONCLUSION: Low HbF levels correlated with poor oxygenation indices and increased risk for ROP. O2 saturation goals to prevent ROP may need to incorporate relative amount of HbF.

Analysis of Clinical Outcomes of Pregnant Patients Treated With Nirmatrelvir and Ritonavir for Acute SARS-CoV-2 Infection.

Importance: Pregnant people are at increased risk of poor outcomes due to infection with SARS-CoV-2, and there are limited therapeutic options available. Objective: To evaluate the clinical outcomes associated with nirmatrelvir and ritonavir used to treat SARS-CoV-2 infection in pregnant patients. Design, Setting, and Participants: This case series included pregnant patients who were diagnosed with SARS-CoV-2 infection, received nirmatrelvir and ritonavir, and delivered their offspring within the Johns Hopkins Health System between December 22, 2021, and August 20, 2022. Exposures: Treatment with nirmatrelvir and ritonavir for SARS-CoV-2 infection during pregnancy. Main Outcomes and Measures: Clinical characteristics and outcomes were ascertained through manual record review. Results: Forty-seven pregnant patients (median [range] age, 34 [22-43] years) were included in the study, and the median (range) gestational age of their offspring was 28.4 (4.3-39.6) weeks. Medication was initiated at a median (range) of 1 (0-5) day after symptom onset, and only 2 patients [4.3%] did not complete the course of therapy because of adverse effects. Thirty patients (63.8%) treated with nirmatrelvir and ritonavir had a comorbidity in addition to pregnancy that could be a risk factor for developing severe COVID-19. Twenty-five patients [53.2%] delivered after treatment with nirmatrelvir and ritonavir. Twelve of these patients [48.0%] underwent cesarean delivery, 9 [75.0%] of which were scheduled. Two of 47 patients [4.3%] were hospitalized for conditions related to preexisting comorbidities. Conclusions and Relevance: In this case series, pregnant patients who were treated with nirmatrelvir and ritonavir tolerated treatment well, although there was an unexpectedly high rate of cesarean deliveries. The lack of an increase in serious adverse effects affecting pregnant patients or offspring suggests that clinicians can use this drug combination to treat pregnant patients with SARS-CoV-2 infection.

Increasing effective postpartum care in an obstetric clinic using ACOG's postpartum toolkit.

BACKGROUND: Approximately 69% of maternal mortality occurs in the postpartum period. Contributing factors include the absence of preparation of pregnant women for the postpartum period during the antenatal period, postpartum follow-up care not being scheduled until 6 weeks after childbirth, and the lack of further care coordination. AIM: The aim of this project was to increase the frequency of effective postpartum care visits to 80% in 8 weeks at an urban obstetric clinic. METHODS: A quality improvement project was conducted through four Plan-Do-Study-Act cycles over 8 weeks. INTERVENTIONS: Postpartum Readiness & Awareness Tools (PRATs) were reviewed with patients during their late third trimester, to review postpartum warning signs that warrant further evaluation. A population health registry was created to manage early follow-up for newly postpartum patients, to ensure their recovery was progressing normally. A note template was created and implemented to guide the completion of comprehensive postpartum visits. RESULTS: Over 8 weeks, 188 patients received 1 of the 3 standardized interventions. Effective postpartum visits increased to 88%. The PRATs increased patient postpartum warning sign knowledge, with a project mean risk factor knowledge score of 6 (Goal = 5). The population health registry drove right care by ensuring early postpartum patients were recovering as expected, as seen by a project mean right-care score of 16 (Goal = 12). The note template increased the effectiveness of postpartum visits, with a mean effective postpartum care score of 10 (Goal = 10). CONCLUSIONS: The PRATs, population health registry, and note template collectively increased the quality and effectiveness of postpartum care.

Maternal siRNA silencing of placental SAA2 mitigates preterm birth following intrauterine inflammation.

The placental inflammatory processes induced maternally result in preterm birth (PTB). Serum amyloid A (SAA) is a well-known biomarker of inflammation. The objective of this study was to investigate whether murine placental SAA isoforms (SAA1-4) participate in the mechanism of spontaneous PTB and whether maternal regulation of SAA production may serve as a therapeutic approach. During the gestation, all isoforms of SAA were detectable except SAA2. The mouse model of intrauterine inflammation was established using LPS infusion to the uterus. Following intrauterine inflammation, placental SAA2 increased significantly. Inhibition of Saa2, using siSaa2, markedly decreased PTB. The increased placental expression of pro-inflammatory cytokines Il1ß, Il6, and Tnfα were downregulated by siSaa2 treatment. Maternal inhibition of Saa2 did not change the expression of Saa1-4 in the fetal brain. Explant inflammatory culture of placentas with siSaa2 showed similar results to our in vivo experiments. This study demonstrates the highly expressed placental SAA2 as a novel therapeutic target, and maternal administration of siRNA as a promising approach to alleviate PTB.