Immunotherapy: ALLOGENEIC UMBILICAL CORD BLOOD REGULATORY T CELLS DECREASE INFLAMMATION AND PRESERVE ANTI-TUMOR ACTIVITY OF CAR T CELLS

Background & Aim: With larger accessibility and increased number of patients being treated with CART cell therapy, real-world toxicity continues to remain a significant challenge to its widespread adoption. We have previously shown that allogeneic umbilical cord blood derived (UCB) regulatory T cells (Tregs) can resolve uncontrolled inflammation and can treat acute and immune mediated lung injury in a xenogenic model as well as in patients suffering from COVID-19 acute respiratory distress syndrome. The unique properties of UCB Tregs including: i) lack of plasticity when exposed to inflammatory micro-environments;ii) no requirement for HLA matching;iii) long shelf life of cryopreserved Tregs;and iv) immediate product availability for on demand treatment, makes them an attractive source for treating acute inflammatory syndromes. Therefore, we hypothesized that add-on therapy with UCB derived Tregs may resolve uncontrolled inflammation responsible for CART cell therapy associated toxicity. Methods, Results & Conclusion(s): UCB Tregs were added in 1:1 ratio to CART cells, where no interference in their ability to kill CD19+ Raji cells, was detected at different ratios : 8:1 (80.4% vs. 81.5%);4:1 (62.0% vs. 66.2%);2:1 (50.1% vs. 54.7%);1:1 (35.4% vs. 44.1%) (Fig 1A). In a xenogenic B cell lymphoma model, multiple injections of Tregs were administered after CART injection (Fig 1B), which did not impact distribution of CD8+ T effector cells (Fig 1C) or CART cells cells (Fig 1D) in different organs. No decline in the CAR T levels was observed in the Tregs recipients (Fig 1E). Specifically, no difference in tumor burden was detected between the two arms (Fig 2A). No tumor was detected in CART+Tregs in liver (Fig 2B) or bone marrow (Fig 2C). A corresponding decrease in multiple inflammatory cytokines in peripheral blood was observed in CART+Tregs when compared to CART alone (Fig 2D). Here we show "proof of concept" for add-on therapy with Tregs to mitigate hyper-inflammatory state induced by CART cells without interference in their on-target anti-tumor activity. The timing of Tregs administration after CART cells have had sufficient time for forming synapse with tumor cells allows for preservation of their anti-tumor cytotoxicity, such that the infused Tregs home to the areas of tissue damage to bind to the resident antigen presenting cells which in turn collaborate with Tregs to resolve inflammation. Such differential distribution of cells allow for a Treg "cooling blanket" and lays ground for clinical study. [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy

Perinatal aspects of sars-cov-2 infection during pregnancy: A potential cause for concern

Ever since the beginning of COVID-19 pandemic, uncertainty regarding clinical presentation and differences among various subpopulations exist. With more than 209,870,000 confirmed cases and more than 4,400,000 deaths worldwide, we are facing the new era of health crisis which will undoubtedly impair global health, economic and social circumstances. In the past year, numerous genetic mutations which code SARS-CoV-2 proteins led to the occurrence of new viral strains, with higher transmission rates. Apart from the implementation of vaccination, the effect of SARS-CoV-2 on pregnancy outcome and maternal fetal transmission remains an important concern. Although neonates diagnosed with COVID-19 were mostly asymptomatic or presented with mild disease, the effect on early pregnancy is yet to be evident. While positive finding of SARS-CoV-2 RNA in some samples such as amniotic fluid, placental tissue, cord blood and breast milk exists, additional research should confirm its association with transplacental transmission.Copyright © 2022, Dr. Mladen Stojanovic University Hospital. All rights reserved.

Impact of SARS-CoV-2 infection in pregnancy on fetal immune state

SARS-CoV-2 infection during pregnancy is associated with increased risk of adverse maternal and pregnancy outcomes. Maternal COVID- 19 is associated with immune activation and inflammatory response in the pregnant individual and an altered immune repertoire in the placenta. Mother-to-child transmission of infection is reported but uncommon. Still, the potential impact of maternal SARS-CoV-2 infection on the immunologic and inflammatory state of the infant is of interest, both for the acute health of the newborn and longer-term outcomes. In this talk, we will discuss the mixed data from cord blood and infant studies of cytokine profiles, transcriptomics, immunophenotyping, and functional studies. We will address the timing and severity of maternal infection as we explore the potential immunological consequences of in utero exposure to maternal SARS-CoV-2 infection.

Transplacental transfer of SARS-CoV-2 variant antibodies following COVID-19 vaccination during pregnancy

Problem: Despite being over 3 years into the pandemic, infants remain highly undervaccinated and at a high risk for hospitalization due to COVID-19. Further investigation as to how maternal health decisions for immunization can reduce morbidity from infant COVID-19 by providing passive immunity is necessary. The objective of this study was to describe the rates of SARS-CoV-2 variant antibody transfer from mother to infant cord blood by trimester ofmaternal vaccination. Methods of study: This is an observational cohort study including mother-infant dyads receiving primary or subsequent booster COVID- 19 vaccines during pregnancy.Unvaccinated, but SARS-CoV-2 infected dyads with were included as a comparison group. We quantified median titer and interquartile range (IQR) for SARS-CoV-2 receptor binding domain (RBD) IgG in infant cord blood samples at delivery using the mesoscale discovery platform (electrochemiluminescence). Primary outcome was infant cord IgG titer by trimester of vaccination for the WA1/2022 RBD IgG and current circulating, immune evasive XBB RBD IgG. Secondary outcome is the percent detectable IgG for each variant. Sensitivity analysis was performed based on known SARS-CoV-2 infection. Result(s): Eighty-three mother-infant dyads were included in this analysis. Seven were vaccinated in the first trimester, 37 in the second trimester, 33 in the third trimester, and 6 were unvaccinated and infected. Twenty-three (30%) of the vaccinated group had known SARS-CoV-2 infection. Most received monovalent mRNA COVID-19 vaccines during pregnancy, aside from two who received the viralvectored Ad26.COV2.S, and two received the bivalent mRNA vaccine during pregnancy. The median cord blood WA1/2020 RBD IgG titer was 5370 (412-7296) for first, 1225 (589-3289) for second, 2623 (664-5809) for third trimester in individuals who received aCOVID-19 vaccine dose during pregnancy, and 45 (10-187) in those unvaccinated and infected. After excluding thosewith infection, the cord blood IgG was 514 (106-4182), 1070 (518-2317), and 2477 (664-4470) for first, second, and third trimester, respectively. The rate of detectable WA1/2020 RBD IgG was 100% for all three trimesters, even when excluding infected individuals. For theXBBvariant, cord bloodRBDIgG titer was 284 (43-1296) for first, 66 (32-227) for second, 173 (45-389) for third trimester, and 10 (10-11) in the unvaccinated/infected group. Excluding infections, the cord blood XBB RBD IgG was 54 (10-128), 44 (25-181), and 152 (45-360) for first, second, and third trimester vaccination, respectively. The rate of detectable XBB IgG in those who received a vaccine during pregnancy were 83%, 91%, and 90% for first, second, and third trimester respectively, compared to 17% in the unvaccinated/infected group. Excluding infections, the rate of XBB RBD IgG detection was 66%, 89%, and 95% for first, second, and third trimester vaccination, respectively. Conclusion(s): Vaccination during pregnancy leads to high rates of detectable cord blood IgG specific to SARS-CoV-2 WA1/2020 variant and current circulating variants (XBB), regardless of trimester of vaccination. Infection history leads to higher cord blood IgG in vaccinated;however, infection alone without vaccination leads to lower titer and greater rates of undetectable cord IgG at delivery.

POLYFUNCTIONAL SARS-CoV-2-SPECIFIC T CELLS PERSIST IN TISSUE OF COVID-19 CONVALESCENTS

Background: T cells play an essential role in SARS-CoV-2 immunity, including in defense against severe COVID-19. However, most studies analyzing SARSCoV- 2-specific T cells have been limited to analysis of blood. Furthermore, the role of T cells in SARS-CoV-2 immunity in pregnant women, which are at disproportionately higher risk of severe COVID-19, is poorly understood. Method(s): Here, we quantitated and deeply phenotyped SARS-CoV-2-specific T cells from convalescent women (n=12) that had mild (non-hospitalized) COVID-19 during pregnancy. Endometrial, maternal blood, and fetal cord blood specimens were procured at term, which ranged from 3 days to 5 months post-infection. SARS-CoV-2-specific T cells were deeply analyzed by CyTOF using a tailored phenotyping panel designed to assess the effector functions, differentiation states, and homing properties of the cells. Result(s): SARS-CoV-2-specific T cells were more abundant in the endometrium than in maternal or fetal cord blood. In a particularly striking example, in one donor sampled 5 months after infection, SARS-CoV-2-specific CD8+ T cells comprised 4.8% of total endometrial CD8+ T cells, while it only reached 1.4% in blood. Endometrial SARS-CoV-2-specific T cells were more frequently of the memory phenotype relative to their counterparts in maternal and fetal cord blood, which harbored higher frequencies of naive T cells. Relative to their counterparts in blood, endometrial SARS-CoV-2-specific T cells exhibited unique phenotypic features, including preferential expression of the T resident memory marker CD69, inflammatory tissue-homing receptor CXCR4, and the activation marker 4-1BB. Endometrial T cells were highly polyfunctional, and could secrete IFNg, TNFa, MIP1b, IL2, and/or IL4 in response to spike peptide stimulation. By contrast, their counterparts in blood preferentially produced the cytolytic effectors perforin and granzyme B. Conclusion(s): Polyfunctional SARS-CoV-2-specific T cells primed by prior exposure to the virus are abundant and persist in endometrial tissue for months after infection. These cells exhibit unique phenotypic features including preferential expression of select chemokine receptors and activation molecules. Compared to their blood counterparts, the effector functions of these cells are more cytokine-driven and less cytolytic. The long-term persistence of these cells in the endometrium may help protect future pregnancies from SARS-CoV-2 re-infection.

SARS-CoV-2 ANTIBODY RESPONSES POST-INFECTION IN PREGNANCY BY VACCINATION STATUS

Background: We evaluated SARS-CoV-2 antibody binding and neutralization responses at delivery among pregnant persons with prior SARS-CoV-2 infection by vaccine status. Method(s): We enrolled participants with evidence of prior SARS-CoV-2 infection detected in pregnancy (anti-nucleocapsid [anti-N] IgG+ on enrollment or prior RT-PCR+ or antigen+) and followed them through delivery. Maternal delivery and cord blood samples were tested for SARS-CoV-2 binding antibodies to spike (anti-S) (from vaccination and/or infection) and anti-N (from infection only) IgG by Abbott Architect followed by neutralizing antibodies (classified as neutralizing if serum dilution inhibited infection by 50% [ND50 heat] >=20 and R2 >=0.9) if sample volume allowed. Positive IgG thresholds were Abbott index >=1.4 for anti-N and >=50 AU/mL for anti-S. Chi-squared test was used to compare differences in proportions between groups. Wilcoxon rank sum test was used to compare medians. Result(s): Among 71 participants with delivery and cord samples, median age was 33 years (interquartile range [IQR] 30-35) and median gestational age was 31.7 weeks (IQR 18.0-37.9) at enrollment in pregnancy. By delivery, 17 (24%) participants were unvaccinated, 21 (30%) were partially vaccinated or had completed a primary series, and 33 (46%) were boosted. Median time from infection (RT-PCR+ or antigen+ result) to delivery was 16.7 weeks (IQR 9.7- 24.3). At delivery, 33 (46%) of maternal (median 3.2 index) and 37 (52%) of cord samples (median 3.1 index) were anti-N IgG+. Participants with >=1 vaccine were more likely to be anti-S IgG+ than those unvaccinated (100% vs. 82%, p< 0.01), have higher median anti-S IgG+ (25,000 vs 1,019 AU/ml, p< 0.01), and have neutralizing antibodies (100% vs. 81%, p< 0.01) with higher median log10 neutralization (1:4.00 vs 1:2.41, p< 0.01) at delivery. Similarly, cord blood from participants with >=1 vaccine was more likely to be anti-S IgG+ than those unvaccinated (100% vs. 82%, p< 0.01), have higher median anti-S IgG+ (25,000 vs 1,188 AU/ml, p< 0.01), and have neutralizing antibodies (100% vs. 75%, p< 0.01) with higher median log10 neutralization (1:4.00 vs 1:2.41, p< 0.01) at delivery. Conclusion(s): Among pregnant people with prior SARS-CoV-2 infection detected during pregnancy, maternal and cord blood antibody binding and neutralization responses were higher among those receiving SARS-CoV-2 vaccination prior to delivery. (Table Presented).

Covid-19 Vaccinated Maternal/Cord Blood Dont Have Neutralization for Omicron Variants

Background: Maternally derived antibodies are crucial for neonatal immunity. Understanding the binding and -cross neutralization capacity of maternal/ cord antibody responses to COVID-19 vaccination during pregnancy can inform neonatal immunity. Method(s): Here we characterized binding and neutralizing antibody profile at delivery in 24 pregnant individuals following two doses of Moderna mRNA-1273 or Pfizer BNT162b2 vaccination. We evaluated the transplacental antibody transfer by profiling maternal and umbilical cord blood. We analyzed for SARS-CoV-2 multivariant cross-neutralizing antibody levels for wildtype Wuhan, Delta, Omicron BA1, BA2, and BA4/BA5 variants by enzyme-linked immunosorbent assay Results: Our results reveal that current vaccination induced significantly higher (p=0.003) RBD-specific binding IgG titers in cord blood compared to maternal blood for both Wuhan and Omicron BA1 strain. Interestingly, binding IgG antibody levels for the Omicron BA1 strain were significantly lower (P< 0.0001) when compared to the Wuhan strain in both maternal and cord blood. In contrast to the binding, the Omicron BA1, BA2, BA4/5 specific neutralizing antibody levels were significantly lower (P< 0.0001) compared to the Wuhan and Delta variants. It is interesting to note that the BA4/5 neutralizing capacity was not at all detected in both maternal and cord blood. Conclusion(s): Our data suggest that the initial series of COVID-19 mRNA vaccines were immunogenic in pregnant women, and vaccine-elicited binding antibodies were detectable in cord blood at significantly higher levels for Wuhan and Delta variants but not for Omicron variants. Interestingly, the vaccination did not induce neutralizing antibodies for Omicron variants. These results provide novel insight into the impact of vaccination on maternal humoral immune response and transplacental antibody transfer for SARS-CoV-2 variants and support the need for boosters as new variants emerge.

Epidemiological study of COVID-19 pneumonia in pregnant woman and their neonates, report of thirteen confirmed COVID-19 pregnant women

Background: In new pandemic, the probable effects of COVID-19 pneumonia on pregnant woman and their infant is one of new critical challenge for health care. Here we presented clinical symptoms, laboratory findings and outcome of COVID-19 pneumonia in pregnant woman. Method(s): In a case series study, from 15 Feb to 15 June 2020, all women with RT-PCR COVID-19 who referred to two hospitals (Taleghani and Qods Hospital) affiliated to Arak University of Medical Sciences were selected. The epidemiological and demographic variables, laboratory test and outcomes obtained from patient's medical records. Result(s): In this case series, we presented thirteen confirmed COVID-19 pregnant women. Their mean age was 34.6 (S.D.: 5.9) years and the mean gestational age was 32.4 (S.D.: 7.3) weeks. Most of patient didn't show any maternal complication and intrauterine vertical transmission. The large number of pregnant women had normal HRCT and also in terms of laboratory most of the patients had normal laboratory tests. Amniotic fluids, cord blood, the throat swab of neonate in our pregnant woman with delivery were tested for COVID-19 and all of them were negative. Conclusion(s): The COVID-19 mothers and their infant didn't have higher risk for morbidity and mortality and this virus didn't associate with intrauterine vertical transmission.Copyright © 2020 Ubiquity Press. All rights reserved.

Mesenchymal Stem Cells: A Potent Cell Source for COVID-19

Coronaviruses are enveloped positive-stranded RNA viruses that cause mild to acute respiratory illness. Coronaviruses can merge envelope proteins with the host cell membranes and de-liver their genetic material. Coronavirus disease 2019 (COVID-19) is the seventh coronavirus clos-est to the severe acute respiratory syndrome (SARS) in bats that infects humans. COVID-19 at-tacks the respiratory system and stimulates the host inflammatory responses, promotes the recruit-ment of immune cells, and enhances angiotensin-converting enzyme 2 (ACE2) activities. Patients with confirmed COVID-19 have experienced fever, dry cough, headache, dyspnea, acute kidney injury (AKI), acute respiratory distress syndrome (ARDS), and acute heart injury. Several strategies such as oxygen therapy, ventilation, antibiotic or antiviral therapy, and renal replacement therapy are commonly used to decrease COVID-19-associated mortality. Inflammation is a common and important factor in the pathogenesis of COVID-19. In recent years, stem cell-based therapies represent a promising therapeutic option against various diseases. Mesenchymal stem cells (MSCs) are multipotent stem cells that can self-renew and differentiate into various tissues of mesodermal ori-gin. MSCs can be derived from bone marrow, adipose tissue, and umbilical cord blood. MSCs, with their unique immunomodulatory properties, represent a promising therapeutic alternative against diseases associated with inflammation. Several previous studies have shown that MSCs with a strong safety profile can improve the treatment of patients with COVID-19. The information in this review provides a summary of the prevention and diagnosis of COVID-19. Also, we focus on the current clinical application of MSCs for treatments of patients with COVID-19.Copyright © 2021 Bentham Science Publishers.

Longitudinal antibody response kinetics following SARS-CoV-2 messenger RNA vaccination in pregnant and nonpregnant persons.

BACKGROUND: For some vaccine-preventable diseases, the immunologic response to vaccination is altered by a pregnant state. The effect of pregnancy on SARS-CoV-2 vaccine response remains unclear. OBJECTIVE: We sought to characterize the peak and longitudinal anti-S immunoglobulin G, immunoglobulin M, and immunoglobulin A responses to messenger RNA-based SARS-CoV-2 vaccination in pregnant persons and compare them with those in nonpregnant, reproductive-aged persons. STUDY DESIGN: We conducted 2 parallel prospective cohort studies among pregnant and nonpregnant persons who received SARS-CoV-2 messenger RNA vaccinations. Blood was collected at the time of first and second vaccine doses, 2 weeks post second dosage, and with serial longitudinal follow-up up to 41.7 weeks post vaccination initiation. Anti-S immunoglobulin M, immunoglobulin G, and immunoglobulin A were analyzed by enzyme-linked immunosorbent assay. We excluded those with previous evidence of SARS-CoV-2 infection by history or presence of antinucleocapsid antibodies. In addition, for this study, we did not include individuals who received a third or booster vaccine dosage during the study period. We also excluded pregnant persons who were not fully vaccinated (14 days post receipt of the second vaccine dosage) by time of delivery and nonpregnant persons who became pregnant through the course of the study. We studied the effect of gestational age at vaccination on the anti-S response using Spearman correlation. We compared the peak anti-S antibody responses between pregnant and nonpregnant persons using a Mann-Whitney U test. We visualized and studied the longitudinal anti-S antibody response using locally weighted scatterplot smoothing, Mann-Whitney U test, and mixed analysis of variance test. RESULTS: Data from 53 pregnant and 21 nonpregnant persons were included in this analysis. The median (interquartile range) age of the pregnant and nonpregnant participants was 35.0 (33.3-37.8) years and 36.0 (33.0-41.0) years, respectively. Six (11.3%) participants initiated vaccination in the first trimester, 23 (43.3%) in the second trimester, and 24 (45.3%) in the third trimester, with a median gestational age at delivery of 39.6 (39.0-40.0) weeks. The median (interquartile range) follow-up time from vaccine initiation to the last blood sample collected was 25.9 (11.9) weeks and 28.9 (12.9) weeks in the pregnant and nonpregnant cohort, respectively. Among pregnant persons, anti-S immunoglobulin G, immunoglobulin A, and immunoglobulin M responses were not associated with gestational age at vaccine initiation (all P>.05). The anti-S immunoglobulin G response at 2 weeks post second dosage was not statistically different between pregnant and nonpregnant persons (P>.05). However, the anti-S immunoglobulin M and immunoglobulin A responses at 2 weeks post second dosage were significantly higher in nonpregnant persons (P<.001 for both). The anti-S immunoglobulin G and immunoglobulin M levels 6 to 8 months after vaccine initiation fell to comparable proportions of the peak 2 weeks post second dosage antibody levels between pregnant and nonpregnant persons (immunoglobulin G P=.77; immunoglobulin M P=.51). In contrast, immunoglobulin A levels 6 to 8 months after vaccine initiation fell to statistically significantly higher proportions of peak 2 weeks post second dosage antibody levels in pregnant compared with nonpregnant persons (P=.002). Maternal anti-S immunoglobulin G levels were strongly correlated with umbilical cord anti-S immunoglobulin G levels (R=0.8, P<.001). CONCLUSION: The anti-S immunoglobulin A, immunoglobulin M, and immunoglobulin G response to SARS-CoV-2 vaccination in pregnancy is independent of gestational age of vaccine initiation. Maintenance of the immunoglobulin G response is comparable between pregnant and nonpregnant persons. The differential peak response of immunoglobulin M and immunoglobulin A and the differential decline of anti-S immunoglobulin A between pregnant and nonpregnant persons requires further investigation.

COVID-19 pandemic and neonatal health: What we know so far?

COVID-19 first time appeared in December 2019 in Wuhan, China. The number of cases increased rapidly in china and outside and the World Health Organization declared a pandemic on 11th March 2020. The pregnant and postpartum women, child, and neonatal populations are vulnerable to this disease due to immunological and physiological changes. This paper analyzed the published evidence for assessing the effect of COVID-19 on neonatal health and health care. Online published literature was searched from PubMed, Google Scholar, and other official webpages using keywords: "coronavirus/COVID-19/new coronavirus 2019"/SARS-CoV-2 and neonatal health/care/outcomes" and reviewed to prepare this article. COVID-19 is the potential to transmit either mother to fetus or mother/caregiver to neonates. However, neonates born from infected mothers did not show significant clinical features. Pharyngeal-swab, amniotic-fluid, cord-blood, and breast-milk test results were not found positive. Health facility-based vaginal/caesarian delivery was considered a low risk of transmission. However, recommended to separate neonates with infected mothers/caregivers and test immediately after birth to avoid the possible transmission. Mothers/caregivers should take routine preventive measures such as washing hands frequently and avoiding contact with infected people. If neonates suffered from the server acute respiratory distress requires intensive care urgently. Despite the possibility of the intrauterine transmission of COVID-19 direct evidence is still lacking so it needs more studies for further confirmation. The International Pediatric Association suggested preventive programs, curative care, vaccination, and telemedicine care as the minimum services and called on its members to address these cares during the pandemic. Copyright © 2020, Kathmandu University. All rights reserved.

Seroprevalence of antibodies against to SARS-CoV 2 in umbilical cord blood in two hospital centers in Córdoba and Sucre, Colombia.

INTRODUCTION: Pregnant women continue to be vulnerable to COVID-19, and their immunosuppressed state could put them at greater risk of developing more severe forms of the disease. In Colombia and Latin America, there are few studies on the immune response of the newborn against SARS-CoV-2. AIM: To determine the prevalence of SARS-CoV-2 infection in umbilical cord blood in two hospital centers in Córdoba and Sucre. METHODS: Between March and June 2021, a prospective descriptive cross-sectional study was carried out. Two hospitals from the departments of Córdoba and Sucre, located in the Northwest Caribbean area of Colombia, participated. Three hundred sixty umbilical cord blood samples were taken at the two hospitals. A commercial ELISA was performed to detect total IgG, IgM, and IgA antibodies against the N protein of SARS-CoV-2. The ethics committee approved the study of the participating institutions. RESULTS: Of 3.291 women who gave birth in the hospital centers included in the study, 360 (11%) participated. Complete clinical data were obtained for 223 women. The mean age of the women was 24 years (range, 15-42). 29.4% (106/360) of the umbilical cord samples had total antibodies against SARS-CoV-2. Pregnant women did not have blood samples taken. 58% of the women were asymptomatic. There was no association between umbilical cord samples, clinical, epidemiological characteristics, and serological response to antibodies to SARS-CoV-2 (p > 0.05). CONCLUSIONS: The prevalence of umbilical cord blood samples was 29.4% for total SARS-CoV-2 antibodies. The study provides essential aspects for the epidemiological approach to neonates infected with SARS-CoV-2.

Maternal COVID-19 Disease and COVID-19 Immunization.

Aim This study aimed to evaluate the immune response and vertical transmission of anti-severe acute respiratory syndrome (SARS) antibodies in vaccinated, expectant mothers infected with coronavirus disease 2019 (COVID-19) and to study the sequelae. Study design This was a retrospective study of pregnant women conducted at Bahrain Defense Force Hospital from March 2021 to September 2021. The study population was divided into two groups: group 1 was vaccinated with Sinopharm or Pfizer/BioNTech during pregnancy and never infected with COVID-19. Group 2 was unvaccinated and had been infected with COVID-19. Immune responses such as anti-nucleocapsid (anti-N) and anti-spike (anti-S) from paired samples of maternal and umbilical cord blood were measured with Elecsys immunoassay (Roche Holding AG: Basel, Switzerland) at the time of delivery. Obstetric complications such as preterm labor, preeclampsia, and stillbirth were assessed. Analysis was performed using SPSS version 26.0 (IBM Corp: Armonk, NY) and Minitab version 18 (Minitab, LLC: State College, PA). A p-value of less than 0.05 was considered statistically significant. Results The study included 90 vaccinated and 90 COVID-19-recovered pregnant women. Matched samples were available for 80 vaccinated and 74 COVID-19-recovered women. Group 1 had significantly higher levels of anti-S for both the mother and the cord blood and a significantly higher transfer ratio of anti-S. Group 2 had higher levels of anti-N. In group 1, the paired sample titer of anti-S had a weak negative correlation with maternal age whereas, in group 2, the mother's anti-N had a weak positive correlation with age. Antibodies of COVID-19-recovered mothers and cord blood had a moderate negative correlation with gestational age, except for the mother's anti-N. In group 1, the transfer ratio of anti-N and anti-S had a statistically significant association with gestational age. Preterm delivery had a high prevalence of anti-transfer ratios of <1, and delivery at >37 weeks had a high prevalence of ≥1. In group 2, 90% of preterm deliveries had transfer ratios of anti-S <1. The latency period of the COVID-19 group had a statistically significant association with the antibody transfer ratio. An interval of less than 100 days had a high prevalence in the ratio of <1. An interval of more than 100 days had a high prevalence in the ratio of ≥1. There was no significant latency period in group 1. Group 1 had a 75% prevalence of an anti-S transfer ratio ≥1 with a birth weight of >3500 g; group 2 had no significance in birth weight. We did not find significance in the sequelae of morbidities in either group. Conclusion The production of the antibody N in the COVID-19-infected and antibody S in the vaccinated pregnant women as well as the vertical transmission of antibodies was efficacious. Significant variation was found regarding maternal age in both groups. The transfer ratio of the antibodies in the vaccinated and COVID-19-recovered women was significantly higher in terms of babies of the vaccinated and the infected population. The transfer ratios were distinct according to the latency period and birth weight of the infants.

ASSESSING GENOMIC SAFETY OF ANTIVIRAL NUCLEOSIDE ANALOGS IN HEMATOPOIETIC STEM CELLS

Background: Nucleoside analog (NAs) drugs are used for the treatment of a variety of diseases, such as cancers and viral infections. After phosphorylation of viral and host kinases, NA drugs compete with the corresponding naturally occurring nucleotide during DNA replication of the infected cell. After incorporation, they can lead to mutations, or chain termination. However, because of their mechanism of action, NA are also potentially mutagenic to the genome of physiologically normal cells. Indeed, we have shown that treatment with the antiviral NA ganciclovir (GCV) after stem cell transplantation induces an increased mutation burden in the hematopoietic stem and progenitor cells (HSPCs) of pediatric leukemia patients. Using mutational signature analysis, we provided evidence that GCV-induced mutagenesis contributes to development of relapses and second malignancies in pediatric patients by inducing driver mutations. Over 30 NA drugs have been approved for clinical use and millions of people receive antiviral treatment worldwide to treat viral infections, including COVID-19. However, the mutagenicity in normal cells and potential carcinogenicity is unclear. Aims: Here, we aimed to systematically assess the mutational consequences of antiviral NAs in human HSPCs and identify underlying mechanisms. Methods: By combining in vitro treatment of umbilical cord blood-derived HSPCs with whole-genome sequencing (WGS) analyses, we provide a compendium of mutational consequences of antiviral NAs in a relevant human tissue (i.e., toxicity to the hematopoietic system is often dose-limiting). We treated HSPCs with IC40-60 concentration of the assessed compound followed by clonal expansions to obtain sufficient DNA for WGS. Using established bioinformatic pipelines, we catalogued the somatic mutations and mutational signatures in these cells. Results: At time of writing, 5 out of 7 tested antiviral NAs induce an enhanced mutation burden in exposed HSPCs. For some of this antiviral NAs we were able to identify unique unreported mutational signatures. Of note, the thymidine analog brivudine showed the highest increase in single base substitutions, which were characterized by a T>C signature, depleted for flanking cytosines. Furthermore, like GCV, we also observed a signature characterized by C>ApA substitution after treatment with the penciclovir, a molecule nearly identical to GCV. Currently we are working on machine learning approach to identify relevant mutation characteristics and modes of action as well as to screen cancer genome databases for mutational signature occurrence. Summary/Conclusion: Many compounds of the NA class currently prescribed for the treatment of viral infections are mutagenic to healthy cells. This calls for more thorough screening of these drugs, incorporation of information on mutagenicity to healthy cells in drug safety guidelines and patient surveillance over time.

Mild or Moderate COVID-19 during Pregnancy Does Not Affect the Content of CD34+ Hematopoietic Stem Cells in Umbilical Cord Blood of Newborns.

The study included umbilical cord blood samples (n=64) intended for cryogenic storage of hematopoietic stem cells and obtained from patients with a history of mild and moderate forms of COVID-19 during pregnancy. The control group was composed of samples (n=746) obtained from healthy women in labor. A comparative analysis of the volume of cord blood collected, the total leukocyte count, the relative and absolute content of cells with the CD34+/CD45+ phenotype revealed no significant differences between the groups.

Antigenic target, antibody subclass, function and glycans and SARS-CoV-2 coinfection impact the placental transfer of herpes simplex virus antibodies

Primary versus recurrent herpes simplex virus 1 or 2 (HSV-1 or HSV- 2) infection during pregnancy carries a higher risk of neonatal herpes suggesting that placental transfer of antibodies protects against transmission and infection. Murine and clinical studies demonstrate that antibody-dependent cellular cytotoxicity (ADCC) provides greater protection than neutralizing antibodies (nAbs) against disseminated neonatal disease. To quantify the relative transfer of HSV-specific Abs with different functions and targets and whether SARS-CoV-2 coinfection modified transfer, we conducted a prospective cohort study of mother-infant dyads prior to and during COVID-19. Total and HSV lysate, glycoprotein D (gD) and glycoprotein B (gB)- specific IgG, IgG1 and IgG3, nAbs, and ADCC were quantified in paired 3rd trimester maternal and cord blood. Transfer ratios (TR) were defined as cord: maternal Ab levels. IgG1 and IgG3 subclass and gD or gB-specific Abs were isolated by column purification and glycan profiles were assessed using mass spectrometry. The pre-COVID study population included 21 term and 15 preterm dyads who were HSV-1 (± HSV-2) seropositive (+) enrolled between 2018-2019 and the peri- COVID cohort included 25 HSV-1 (±HSV-2)+term dyadswhosemothers were also SARS-CoV-2 PCR and COVID Ab+ at delivery;14 were asymptomatic and 11 had mild-moderate COVID disease. None of the mothers had active genital HSV lesions during delivery. HSV-specific IgG, IgG1, and IgG3 TR were higher in term compared to preterm pre-COVID dyads (all p< 0.05). Similarly, the neutralizing Ab TR was 2.4[1.5, 4.0] in term vs 0.8[0.6, 1] in preterm (median [95%CI], p< 0.0001) but the ADCC TR was < 1.0 for both groups. To determine if the low ADCC TR reflected antigenic target, subclass, and/or glycans, we enriched for anti-gD and anti-gB specific and IgG1 and IgG3 Abs. These envelope glycoproteins are primary targets of neutralizing and ADCC responses, respectively. The anti-gD Abs were exclusively IgG1 and had only neutralizing activity. In contrast, anti-gB Abs were both IgG1 and IgG3;the IgG1 gB Abs had both neutralizing and ADCC activity whereas the IgG3 were only neutralizing. The anti-gD Abs were enriched for glycans associated with an affinity for FcRn, whereas anti-gB Abs expressed glycans associated with both FcRn and FcγRIIIa (receptor-associated with ADCC activity) binding. There was no significant difference in HSV-specific IgG TR in pre-COVID vs COVID dyads (0.42) but the nAb TR was lower (p = 0.018) and ADCC TR higher (p<0.001) in COVID compared to pre-COVID patients. Studies are in progress to assess whether this reflects increased placental colocalization of FcRn and FcgRIIIA, which would favor the transfer of ADCCAbs or modified Fc glycans. ADCC Abs transfer relatively inefficiently compared to nAbs, particularly in preterm infants and this may contribute to an increased risk of HSV disease. ADCC Ab transfer increased with SARS-CoV-2 coinfection, which may reflect differences in glycans and/or alterations in the placental architecture. Defining the determinants of ADCC transfer has implications for future vaccine and monoclonal Ab strategies to prevent/treat neonatal herpes. We speculate that increasing the transfer of ADCC may be a key element in providing immune protection.

Predictors of Covid-19 Vaccination Response After In-Vivo T-Cell-Depleted Stem Cell Transplantation.

Covid-19 vaccination is recommended in allogeneic transplant recipients, but many questions remain regarding its efficacy. Here we studied serologic responses in 145 patients who had undergone allogeneic transplantation using in vivo T-cell depletion. Median age was 57 (range 21-79) at transplantation and 61 (range 24-80) at vaccination. Sixty-nine percent were Caucasian. One third each received transplants from HLA-identical related (MRD), adult unrelated (MUD), or haploidentical-cord blood donors. Graft-versus-host disease (GVHD) prophylaxis involved in-vivo T-cell depletion using alemtuzumab for MRD or MUD transplants and anti-thymocyte globulin for haplo-cord transplants. Patients were vaccinated between January 2021 and January 2022, an average of 31 months (range 3-111 months) after transplantation. Sixty-one percent received the BNT162b2 (bioNtech/Pfizer) vaccine, 34% received mRNA-1273 (Moderna), and 5% received JNJ-78436735 (Johnson & Johnson). After the initial vaccinations (2 doses for BNT162b2 and mRNA-1273, 1 dose for JNJ-7843673), 124 of the 145 (85%) patients had a detectable SARS-CoV-2 spike protein (S) antibody, and 21 (15%) did not respond. Ninety-nine (68%) had high-level responses (≥100 binding antibody units [BAU]/mL)m and 25 (17%) had a low-level response (<100 BAU/mL). In multivariable analysis, lymphocyte count less than 1 × 109/ mL, having chronic GVHD, and being vaccinated in the first year after transplantation emerged as independent predictors for poor response. Neither donor source nor prior exposure to rituximab was predictive of antibody response. SARS-CoV-2 vaccination induced generally high response rates in recipients of allogeneic transplants including recipients of umbilical cord blood transplants and after in-vivo T cell depletion. Responses are less robust in those vaccinated in the first year after transplantation, those with low lymphocyte counts, and those with chronic GVHD.

COVID-19 Infection During Pregnancy Induces Differential Gene Expression in Human Cord Blood Cells From Term Neonates.

Background: The COVID-19 pandemic continues worldwide with fluctuating case numbers in the United States. This pandemic has affected every segment of the population with more recent hospitalizations in the pediatric population. Vertical transmission of COVID-19 is uncommon, but reports show that there are thrombotic, vascular, and inflammatory changes in the placenta to which neonates are prenatally exposed. Individuals exposed in utero to influenza during the 1918 pandemic had increased risk for heart disease, kidney disease, diabetes, stomach disease and hypertension. Early exposure of COVID-19 during fetal life may lead to altered gene expression with potential long-term consequences. Objective: To determine if gene expression is altered in cord blood cells from term neonates who were exposed to COVID-19 during pregnancy and to identify potential gene pathways impacted by maternal COVID-19. Methods: Cord blood was collected from 16 term neonates (8 exposed to COVID-19 during pregnancy and 8 controls without exposure to COVID-19). Genome-wide gene expression screening was performed using Human Clariom S gene chips on total RNA extracted from cord blood cells. Results: We identified 510 differentially expressed genes (374 genes up-regulated, 136 genes down-regulated, fold change ≥1.5, p-value ≤ 0.05) in cord blood cells associated with exposure to COVID-19 during pregnancy. Ingenuity Pathway Analysis identified important canonical pathways associated with diseases such as cardiovascular disease, hematological disease, embryonic cancer and cellular development. Tox functions related to cardiotoxicity, hepatotoxicity and nephrotoxicity were also altered after exposure to COVID-19 during pregnancy. Conclusions: Exposure to COVID-19 during pregnancy induces differential gene expression in cord blood cells. The differentially expressed genes may potentially contribute to cardiac, hepatic, renal and immunological disorders in offspring exposed to COVID-19 during pregnancy. These findings lead to a further understanding of the effects of COVID-19 exposure at an early stage of life and its potential long-term consequences as well as therapeutic targets.

TGF-Β2 IS ASSOCIATED with ASYMPTOMATIC/MILD SARS-CoV-2 INFECTION during PREGNANCY

Background: COVID-19 has been a devastating disease and a major public health concern mainly to susceptible populations. Methods: We accessed two groups of pregnant women at the time of delivery: SARS-CoV2 active infection and convalescents. To investigate the factors contributing to COVID19 severity we have assessed several immunological parameters including cytokines/chemokine levels in the maternal and cord blood plasma. We have evaluated 33 cytokines. Our findings were validated in vitro in HTBE (Human tracheobronchial epithelial) cells infected with live SARS-COV2 (wild type). Results: Our cohort was enriched in high-risk subjects, including African American and obese women. Only 6% had severe or critical disease, contrasting with the 20-25% reported in some pregnant cohorts. TGFb2 levels were significantly associated with asymptomatic/mild disease in both active and convalescent cohorts, and inversely correlated with IP10, IL6 and IL8, known to be part of the cytokine storm post-infection. Pre-treatment of HTBE with TGFb2 for 48 hours led to a significant decay in viral loads at 72h post-infection. This control was associated with significantly higher IL-6 (IFNb2) levels prior to infection, and significantly higher expression of anti-viral genes at 72h pi (MX1, IFNA1, IFNA2, IFNL1, STAT1). Additionally, TGFb2 pre-treatment suppressed the expression of the cytokines IP-10, IL1b and IL8. Conclusion: Altogether this data suggested that TGFB2 plays a protective role in SARS-COV2 infection in this high-risk population by improving epithelial cells intrinsic antiviral function and by modulating the expression of the cytokines associated to the heightened inflammation in severe cases.