ABSTRACT The adherens junction component, alpha-T-catenin (αTcat) is an established contributor to cardiomyocyte junction structure and function, but recent genomic studies link CTNNA3 polymorphisms to diseases with no clear cardiac underpinning, including asthma, autism and multiple sclerosis, suggesting causal contributions from a different cell-type. We show Ctnna3 mRNA is highly expressed in peripheral nerves (e.g. vagus and sciatic), where αTcat protein enriches at paranodes and myelin incisure adherens junctions of Schwann cells. We validate αTcat immunodetection specificity using a new Ctnna3-knock-out fluorescence reporter mouse line yet find no obvious Schwann cell loss-of-function morphology at the light microscopic level. CTNNA3/Ctnna3 mRNA is also abundantly detected in oligodendrocytes of the central nervous system via public databases, supporting a general role for αTcat in these unique cell–cell junctions. These data suggest that the wide range of diseases linked to CTNNA3 may be through its role in maintaining neuroglial functions of central and peripheral nervous systems. This article has a corresponding First Person interview with the co-first authors of the paper.
Genomic evidence for dysregulated glutamine metabolism in the asthmatic airway epithelium
Background:As the vaccination campaign in response to the coronavirus disease 2019 (COVID-19) pandemic continues, concerns with regard to adverse reactions to the vaccine remain. Although immediate hypersensitivity reactions have received much attention, delayed systemic urticarial reactions after vaccination can occur.Objective:To describe the clinical presentation, vaccine excipient skin testing results, and outcomes of subsequent COVID-19 vaccination in patients who experienced delayed systemic urticarial reactions after messenger RNA (mRNA) COVID-19 vaccination.Methods:This was a retrospective case series of 12 patients referred to the Mayo Clinics in Rochester, Minnesota, and Jacksonville, Florida, between January 19, 2021, and April 30, 2021, for evaluation of delayed systemic urticarial reactions after mRNA COVID-19 vaccination. Demographics, medical and allergic history, reaction details, vaccine excipient skin testing results (when performed), and the outcome after subsequent vaccination were collected for each patient.Results:The mean age of the patients was 52 years, all were white, and 9 (75%) were women. Half of the patients had a history of drug allergy, and one had a history of chronic spontaneous urticaria. Seven patients reacted to the Pfizer-BioNTech vaccine and five reacted to the Moderna vaccine. Seven patients developed symptoms between 8 and 24 hours after vaccination. Nine patients required antihistamines for treatment. The median time to symptom resolution was 4 days. Nine patients underwent allergist-directed COVID-19 vaccine excipient skin testing, all of which were negative. Ten patients chose to receive their next mRNA COVID-19 vaccine dose, and four patients experienced recurrent delayed urticaria.Conclusion:Delayed systemic urticarial reactions after mRNA COVID-19 vaccination were not life-threatening, could be treated with antihistamines, and were not predicted with vaccine excipient skin testing. They were not a contraindication to subsequent vaccination, although patients should be counseled with regard to the possibility of recurrence.
State-of-the-art beta-adrenoreceptor agonists for the treatment of asthma
Background: It remains unclear if asthma is a risk factor associated with worse outcomes among patients with coronavirus disease 2019 (COVID-19). Methods: We performed a comprehensive database search for studies published from January 1, 2019, to October 2, 2020. We included studies that evaluated outcomes among patients with COVID-19 and underlying asthma. Outcomes of interest included the need for hospitalization, length of hospitalization, intensive care unit (ICU) admission, and death. The meta-analysis was conducted by using random-effects methodology. Results: A total of 389 studies were identified through data base searches. After abstract and full-text screening, 16 observational studies with 92,275 patients were included in the analysis. Of the 16 studies, 15 were retrospective and 1 was a prospective cohort study. The average age was 39.6 years, with 48% female patients. Six of the studies included pediatric patients, and one of these studies only evaluated pediatric patients. One study only evaluated pregnant patients. Among patients with COVID-19, the presence of asthma was not associated with any significant increase in risk of hospitalization (odds ratio [OR] 1.46 [95% confidence interval {CI}, 0.29-7.28]), length of hospitalization (1.59 days [‐0.55 to 3.74]), ICU admission (OR 1.65 [95% CI, 0.56-4.17]), or death (OR 0.73 [95% CI, 0.38-1.40]). The overall risk of bias of the included studies was high. Conclusion: Among the patients with COVID-19, asthma did not seem to significantly increase the risk of hospitalization, length of hospitalization, ICU admission, or death.
Senolytics reduce coronavirus-related mortality in old mice
Senescent cells exacerbate COVID-19 Cellular senescence is a state elicited in response to stress signals and is associated with a damaging secretory phenotype. The number of senescent cells increases with advanced age and this in turn drives age-related diseases. Camell et al. show that senescent cells have an amplified inflammatory response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (see the Perspective by Cox and Lord). This response is communicated to nonsenescent cells, suppressing viral defense mechanisms and increasing the expression of viral entry proteins. In old mice infected with a SARS-CoV-2–related virus, treatment with senolytics to reduce the senolytic cell burden reduced mortality and increased antiviral antibodies. Science , abe4832, this issue p. eabe4832 ; see also abi4474, p. 281
Passive siRNA transfection method for gene knockdown in air-liquid interface airway epithelial cell cultures
Differentiation of human bronchial epithelial cells (HBEs) in air-liquid interface (ALI) cultures recapitulates organotypic modeling of the in vivo environment. Although ALI cultures are invaluable for studying the respiratory epithelial barrier, loss-of-function studies are limited by potentially cytotoxic reagents in classical transfection methods, the length of the differentiation protocol, and the number of primary epithelial cell passages. Here, we present the efficacy and use of a simple method for small interfering RNA (siRNA) transfection of normal HBEs (NHBEs) in ALI cultures that does not require potentially cytotoxic transfection reagents and does not detrimentally alter the physiology or morphology of NHBEs during the differentiation process. This transfection protocol introduces a reproducible and efficient method for loss-of-function studies in HBE ALI cultures that can be leveraged for modeling the respiratory system and airway diseases.
Artificial Intelligence (AI)-Based Asthma Phenotype as a Computational Biomarker Predicting Asthma Prognosis
TP10. TP010 CLINICAL AND POPULATION-LEVEL STUDIES OF ASTHMA | May 4, 2021 | Volume: No volume available | Issue: No issue available | Pages: A1473-A1473
There is marked sexual dimorphism in the current coronavirus disease 2019 (COVID-19) pandemic. Here we report that estrogen can regulate the expression of angiotensin-converting enzyme 2 (ACE2), a key component for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cell entry, in differentiated airway epithelial cells. Further studies are required to elucidate the mechanisms by which sex steroids regulate SARS-CoV-2 infectivity.