Vitamin D enhances type I IFN signaling in COVID-19 patients

The ability of Vitamin D (VitD) to modulate antiviral responses through induction of antimicrobial peptide is well established. However, the effect of VitD on host responses to SARS-CoV-2 is not well investigated. We here report the ability of VitD to enhance host IFN-alpha/beta (a/β) signaling both in vitro and among severe COVID-19 patients treated with VitD. Blood and saliva specimens were obtained from severe COVID-19 patients treated (43 patients), or not (37 patients), with vitD, during their stay in intensive care unit. Patients were followed up to 29 days following admission, and patient survival outcomes were collected. Higher activity levels of RIG-1/MDA-5 and JAK-STAT signaling pathways were observed with significantly higher gene and protein levels of antiviral interferon stimulating genes (ISGs) such as MX-1 and ISG-15; both in vitro, following treatment of PBMCs with vitD, and in whole blood and saliva specimens of VitD treated patients. Moreover, VitD treated patients had lower risk of all-cause mortality by day 29 compared to untreated patients (adjusted hazard ratio, 0.37, 95% confidence interval of 0.14–0.94; P = 0.038). The herein uncovered regulatory role of VitD on type I IFNs suggests the importance of insuring a normal level of VitD for the prevention and probably treatment of SARS-CoV-2 infection. Additional mechanistic studies, however, are needed to fully elucidate the antiviral effects of VitD particularly in the setting of COVID-19 infection

Vitamin D modulates systemic inflammation in patients with severe COVID-19

Aims The ability of vitamin D (VitD) to modulate immune responses in the clinical setting of COVID-19 infection is not well investigated. This study aimed to evaluate the ability of VitD to attenuate inflammatory responses in patients with severe COVID-19. Materials and methods Blood samples and nasopharyngeal swabs were obtained from patients with severe COVID-19 who had been treated (20 patients), or not (25 patients), with VitD, during their stay in the intensive care unit. Western blotting was used to evaluate the expressions of STAT3, JNK and AKT signaling pathways and ELISA was used to measure levels of IL-6, IL-17, and IL-1β in blood of these patients. Key findings Reduced levels of STAT3, JNK and AKT pathways and lower levels of proinflammatory cytokines such as IL-6, IL-17, and IL-1β were observed in VitD treated patients (50,000 IU of cholecalciferol weekly for 3 weeks), and in vitro following treatment of poly I:C stimulated PBMCs with VitD (50 nM of calcitriol). Moreover, lower circulatory levels of these proinflammatory cytokines following treatment with VitD were associated with lower serum levels of COVID-19-related severity markers such as D-dimer and C-reactive proteins (

Multiple inborn errors of type I IFN immunity in a 33-year-old male with a fatal case of COVID-19

The host genetic inborn errors of immunity (IEIs) have been shown to contribute to susceptibility to life-threatening coronavirus disease 2019 (COVID-19), as it had been associated previously with other viral infections. Most genetic association studies have described IEIs as a monogenic defect, while there have been no reports of patients with multiple inherited immune deficiencies. This is a complex case of IEIs predisposing to severe viral infections in an unvaccinated 33-year-old male patient. The patient was admitted with no respiratory symptoms, showed a SARS-CoV-2 PCR positive test on the second day of admission, started developing progressive lung consolidation within three days of hospitalization, and was moved from non-invasive to mechanical ventilation within 12 days of hospitalization. Impaired production of type I IFN was detected in patient PBMCs treated with poly(I:C), at both mRNA and protein levels. Whole exome sequencing revealed three mutations across type I IFN production pathway, which were predicted to be loss-of-function (pLOF). The three mutations were predicted to predispose to severe viral infections: monoallelic R488X TLR3, monoallelic His684Arg TLR3, and biallelic Val363Met IRF3. Functional analysis confirmed that all these mutations dysregulated the type I IFN pathway. Evaluation of TLR3 and IRF3 IFN-β1 luciferase reporter activity showed a hypomorphic suppression of function. TOPO TA cloning was used to ascertain the positioning of both TLR3 variants, indicating that both variants were on the same allele. We have described a unique complex IEI patient with multiple mutations, particularly along type I IFN production pathway

Determinants of healthcare workers perceptions, acceptance and choice of COVID-19 vaccines: a cross-sectional study from the United Arab Emirates

Acceptance of COVID-19 vaccine among health-care workers (HCWs) is crucial for controlling the pandemic and ensuring HCW and patient safety. Information on the acceptance of different COVID-19 vaccines is lacking. Despite the United Arab Emirates (UAE) having vaccinated most of its population, vaccine acceptance still raises concerns. This study explores COVID-19 vaccine acceptance, vaccine choice, and associated factors among HCWs in the UAE. An online national cross-sectional study was conducted among 517 HCWs. Acceptance and choice of COVID-19 vaccines were assessed, and logistic regression analysis identified predictors for vaccine acceptance. More than half (58%) of HCWs were willing to take the vaccine and give it to their family. Reasons for taking the vaccine were concerns for families contracting COVID-19 (67%) and social responsibility (64%). Reasons for refusals included concerns with side-effects (61%). Most HCWs knew of the Pfizer (79%) and Sinopharm (57%) vaccines; however, acceptance was higher for Pfizer (35%) and AstraZeneca (21%) vaccines. Being male and being influenza vaccinated predicted willingness to take the vaccine (aOR: 2.34; 95% CI:1.34–4.08; p ≤ 0.001) and (aOR: 2.13; 95% CI: 1.29–3.51; p ≤ 0.001), respectively. HCWs who expressed concerns with inadequate safety data were less likely to take the vaccine (aOR: 0.17; 95% CI: 0.10–0.30; p ≤ 0.001). Additionally, side effects, perception of risk, and level of trust of company and country of manufacture predicted acceptance and choice of vaccines. Effective vaccine policy campaigns to improve acceptance should target HCW’s knowledge and awareness of perceived risks of COVID-19, safety data, social responsibility, and individual preferences for vaccine choice

Increased blood immune regulatory cells in severe COVID-19 with autoantibodies to type I interferons

Abstract The hallmark of severe COVID-19 is an uncontrolled inflammatory response, resulting from poorly understood immunological dysfunction. While regulatory T (Treg) and B (Breg) cells, as the main elements of immune homeostasis, contribute to the control of hyperinflammation during COVID-19 infection, we hypothesized change in their levels in relation to disease severity and the presence of autoantibodies (auto-Abs) to type I IFNs. Cytometric analysis of blood of 62 COVID-19 patients with different severities revealed an increased proportion of conventional (cTreg; CD25+FoxP3+) and unconventional (uTreg; CD25-FoxP3+) Tregs, as well as the LAG3+ immune suppressive form of cTreg/uTreg, in the blood of severe COVID-19 cases compared to the milder, non-hospitalized cases. The increase in blood levels of cTreg/uTreg, but not LAG3+ cTreg/uTreg subtypes, was even higher among patients with severe COVID-19 and auto-Abs to type I IFNs. Regarding Bregs, compared to the milder, non-hospitalized cases, the proportion of IL-35+ and IL-10+ Bregs was elevated in the blood of severe COVID-19 patients, and to a higher extent in those with auto-Abs to type I IFNs. Moreover, blood levels of cTreg, LAG3+ cTreg/uTreg, and IL-35+ and IL-10+ Breg subtypes were associated with lower blood levels of proinflammatory cytokines such as IL-6, IL-17, TNFα, and IL-1β. Interestingly, patients who were treated with either tocilizumab and/or a high dose of Vitamin D had higher blood levels of these regulatory cells and better control of the proinflammatory cytokines. These observations suggest that perturbations in the levels of immunomodulatory Tregs and Bregs occur in COVID-19, especially in the presence of auto-Abs to type I IFNs

Clinical parameters of COVID-19 patients in according to disease severity.

Clinical parameters of COVID-19 patients in according to disease severity.</p

Increased IL-17 level in saliva of severe COVID-19 patients associated with higher need for mechanical ventilation and/or death by days 29.

Kaplan–Meier survival curves of the need for mechanical ventilation (A-C) and/or death (D-F), based on the IL-17, TNFα, and IL-1β cytokine levels in saliva of patients with severe COVID-19 (n = 53). Statistical test: Cox proportional models adjusted for patient’s demographics factors (age, gender, and body mass index), comorbidities (diabetes mellitus), and COVID-19 related severity serum markers (D-dimer, CRP, and ferritin), with significance indicated by P value of less than 0.05.</p

Increased IL-17 gene expression levels in lung and nasopharyngeal swabs of COVID-19 patients.

(A) IL-17 mRNA levels in nasopharyngeal swabs of COVID-19 patients compared to healthy controls (n = 430 COVID-19 patients vs n = 54 healthy controls; GSE152075). (B) IL-17 mRNA levels in lung autopsies of COVID-19 patients compared to healthy controls (n = 17 SARS-CoV-2 infected lung vs. n = 5 healthy lung biopsies; GSE150316). Statistical test: Unpaired t-test or Mann-Whitney U test, depending on the skewness of the data, * P (PDF)</p

Correlation between IL-17 expression level and Th-17 signaling related cytokines/chemokines such as TNFα, IL-1β, IFNγ, IL-6, neutrophils chemoattractant IL-8, and monocytes chemoattractant, CCL2 in nasopharyngeal swabs of COVID-19 patients (n = 430 COVID-19 patients; GSE152075).

Data show that IL-17 in these COVID-19’s nasopharyngeal swabs positively correlate with levels of IL-1β, TNFα, IL-6, IL-8 and CCL2, but not IFNγ. Statistical test: Pearson’s coefficient test with two-tailed p-value (PDF)</p

Study raw data.

(SAV)</p