Prenatal SARS-CoV-2 infection alters postpartum human milk-derived extracellular vesicles (preprint)

Human milk-derived extracellular vesicles (HMEVs) are crucial functional components in breast milk, contributing to infant health and development. Maternal conditions could affect HMEV cargos; however, the impact of SARS-CoV-2 infection on HMEVs remains unknown. This study evaluated the influence of SARS-CoV-2 infection during pregnancy on postpartum HMEV molecules. Milk samples (9 prenatal SARS-CoV-2 vs. 9 controls) were retrieved from the IMPRINT birth cohort. After defatting and casein micelle disaggregation, 1 mL milk was subjected to a sequential process of centrifugation, ultrafiltration, and qEV-size exclusion chromatography. Particle and protein characterizations were performed following the MISEV2018 guidelines. EV lysates were analyzed through proteomics and miRNA sequencing, while the intact EVs were biotinylated for surfaceomic analysis. Multi-Omics was employed to predict HMEV functions associated with prenatal SARS-CoV-2 infection. Demographic data between the prenatal SARS-CoV-2 and control groups were similar. The median duration from maternal SARS-CoV-2 test positivity to milk collection was 3 months (range: 1-6 months). Transmission electron microscopy showed the cup-shaped nanoparticles. Nanoparticle tracking analysis demonstrated particle diameters of <200 nm and yields of >1e11 particles from 1 mL milk. Western immunoblots detected ALIX, CD9 and HSP70, supporting the presence of HMEVs in the isolates. Thousands of HMEV cargos and hundreds of surface proteins were identified and compared. Multi-Omics predicted that mothers with prenatal SARS-CoV-2 infection produced HMEVs with enhanced functionalities involving metabolic reprogramming and mucosal tissue development, while mitigating inflammation and lower EV transmigration potential. Our findings suggest that SARS-CoV-2 infection during pregnancy boosts mucosal site-specific functions of HMEVs, potentially protecting infants against viral infections. Further prospective studies should be pursued to reevaluate the short- and long-term benefits of breastfeeding in the post-COVID era.

Is Blood Type Associated with COVID-19 Severity? (preprint)

Blood type purportedly influences susceptibility to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, but whether it affects severity of coronavirus disease 2019 (COVID-19) is unclear. Therefore, we examined the association of blood type and rhesus with hospitalization and disease severity among 428 COVID-19 patients diagnosed at the University of Cincinnati health system. In the sample, 50.2% of participants had the blood type O, 38.7% had the blood type A, 17.5% had the blood type B, and 3.5% had the blood type AB. In analysis adjusted for sociodemographic characteristics and comorbidities, the blood types A (OR: 0.90, 95% CI: 0.54, 1.50), B (OR: 0.93, 95% CI: 0.51, 1.69), AB (OR: 0.69, 95% CI: 0.20, 2.41), and O (OR: 1.18, 95%: 0.74, 1.98) were not associated with hospitalization for COVID-19. Similarly, the blood types A (OR: 0.93, 95% CI: 0.52, 1.65), B (OR: 0.92, 95% CI: 0.46, 1.84), AB (OR: 0.30, 95% CI: 0.04, 2.44), and O (OR: 1.25, 95%: 0.73, 2.14) were not associated with admission to intensive care unit or death in COVID-19. In conclusion, blood type is not associated with hospitalization or disease severity in COVID-19; therefore, it may not be useful marker for identifying patients at risk for severe COVID-19.

Factors Associated with Hospitalization and Disease Severity in a Racially and Ethnically Diverse Population of COVID-19 Patients (preprint)

Background: The coronavirus disease (COVID-19) first identified in Wuhan in December 2019 became a pandemic within a few months of its discovery. The impact of COVID-19 is due to both its rapid spread and its severity, but the determinants of severity have not been fully delineated. Objective: Identify factors associated with hospitalization and disease severity in a racially and ethnically diverse cohort of COVID-19 patients. Methods: We analyzed data from COVID-19 patients diagnosed at the University of Cincinnati health system from March 13, 2020 to May 31, 2020. Severe COVID-19 was defined as admission to intensive care unit or death. Logistic regression modeling adjusted for covariates was used to identify the factors associated with hospitalization and severe COVID-19. Results: Among the 689 COVID-19 patients included in our study, 29.2% were non-Hispanic White, 25.5% were non-Hispanic Black, 32.5% were Hispanic, and 12.8% were of other race/ethnicity. About 31.3% of patients were hospitalized and 13.2% had severe disease. In adjusted analyses, the sociodemographic factors associated with hospitalization and/or disease severity included older age, non-Hispanic Black or Hispanic race/ethnicity (compared to non-Hispanic White), and smoking. The following comorbidities: diabetes, hypercholesterolemia, asthma, COPD, chronic kidney disease, cardiovascular diseases, osteoarthritis, and vitamin D deficiency were associated with hospitalization and/or disease severity. Hematological disorders such as anemia, coagulation disorders, and thrombocytopenia were associated with both hospitalization and disease severity. Conclusion: This study confirms race and ethnicity as predictors of severe COVID-19. It also finds clinical risk factors for hospitalization and severe COVID-19 not previously identified such a vitamin D deficiency, hypercholesterolemia, osteoarthritis, and anemia.