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1.
Gastroenterology ; 162(7):S-1252, 2022.
Article in English | EMBASE | ID: covidwho-1967441

ABSTRACT

Introduction We sought to evaluate the longitudinal serological response from the second to third dose of SARS-CoV-2 vaccine in liver transplant recipients at our institution. This study is ongoing and the total N will increase. Methods We prospectively enrolled 54 LT patients who received Pfizer-BioNTech or Moderna vaccine in two doses 3-4 weeks apart at our institution and an additional third dose after CDC approval in August 2021. 6 patients were excluded because of a positive nucleocapsid Ab after the third dose that indicated prior COVID infection. Recipients had semi-quantitative spike IgG and nucleocapsid IgG titers tested between 30 and 75 days after receiving a second vaccine dose. Serological responses to both spike and nucleocapsid antigens indicated COVID-19 infection. All recipients had spike and nucleocapsid Ab titers checked at least 14 days after receiving the third dose. Recipients who had a positive spike Ab titer and negative nucleocapsid titer after a second vaccine dose had repeat spike and nucleocapsid Ab testing within 1 week prior to receiving their third vaccine dose. Results Among 48 LT recipients that met inclusion criteria, seropositivity for spike Ab increased from 47.9% after the second dose to 81.3% after the third dose. 9 patients who were seronegative after a third dose had failed to develop detectable spike Ab after their second dose. The median interval between the second and third doses was 5.9 months. After the third dose, 69% of seropositive recipients had a high spike Ab titer. In 25 recipients who were seronegative after a second dose, 64% produced spike Abs after their third dose. Recipients who remained seronegative after 3 vaccine doses had significantly higher mean tacrolimus trough concentrations. To assess whether spike Ab titers waned after the second vaccine dose, we retested spike Ab titers within one week prior to the third dose in 14 out of 23 recipients who were seropositive after their second dose. All 14 patients had a decline in their spike Ab titers after their second dose. Previously detectable spike Ab titers became undetectable in 5 recipients. However, all five of these patients regained detectable spike Ab after the third vaccine. Discussion We demonstrate that a third dose of mRNA SARS-CoV-2 vaccine in LT recipients was effective. Minimizing immunosuppression by lowering tacrolimus trough thresholds is one potential strategy to improve immune responses. Our results also provide useful information about the optimal interval between the second and third vaccine doses in SOT recipients. Our cohort received the third vaccine dose after a longer delay of 6 months. With this delay, we demonstrated higher seropositivity and seroconversion rates than those reported after shorter interval dosing. A shorter delay between doses is a practical approach to help mitigate the immediate risk in this population. (Table Presented)

2.
Gastroenterology ; 162(7):S-652, 2022.
Article in English | EMBASE | ID: covidwho-1967353

ABSTRACT

Introduction: Patients with inflammatory bowel disease (IBD) treated with anti-TNF therapy exhibit attenuated humoral immune responses to vaccination against SARS-CoV-2. The gut microbiota and its functional metabolic output, which are perturbed in IBD, play an important role in shaping host immune responses. We explored whether the gut microbiota and metabolome could explain variation in anti-SARS-CoV-2 vaccination responses in immunosuppressed IBD patients. Methods: Faecal and serum samples were prospectively collected from patients with IBD established on infliximab therapy (for >12 weeks) who were undergoing vaccination against SARS-CoV-2. The Roche Elecsys Anti-SARS-CoV-2 spike (S) and nucleocapsid (N) immunoassays were used to measure antibody responses following two doses of either ChAdOx1 nCoV-19 or BNT162b2 vaccine. Seroconversion was defined by a cut-off anti-S concentration of 15 U/ml, which correlated with 20% viral neutralization;anti-S antibody concentration of < 380 U/ml was indicative of poor response to vaccination. Patients with serological evidence of prior SARS-CoV-2 infection were excluded from the analysis. Faecal calprotectin measurement, 16S rRNA gene amplicon sequencing, nuclear magnetic resonance (NMR) spectroscopy and bile acid profiling with ultra-performance liquid chromatography mass spectrometry (UPLC-MS) were performed on faecal samples. Results: Forty-five infliximab-treated patients were recruited (median age 40 [range 19-67];32 Crohn's disease, 13 ulcerative colitis;28 with concomitant immunomodulator therapy;six with prior infection). 14 patients (35%) had seroconverted after one dose of vaccine and 37 (95%) seroconverted after two doses. 18 patients (46%) had a poor response after two doses of vaccine. There was no association between faecal calprotectin and vaccine response (p=0.41). No differences between satisfactory and poor vaccine responders were noted in alpha or beta diversity of the gut microbiota. The faecal metabolome of satisfactory responders was enriched in the microbial metabolite trimethylamine (q=0.03). Trends were noted linking the short chain fatty acid butyrate with satisfactory response (P=0.01) and succinate with poor response (P=0.06). No significant differences in primary or secondary bile acids were found to associate with vaccine response. The butyrate-producing genus Roseburia was positively correlated with faecal butyrate abundance (q=0.03). Conclusion: Our data suggest an association between gut microbiota function and variable serological response to vaccination against SARS-CoV-2 in immunocompromised patients. Microbial metabolites including trimethylamine and butyrate may be important in mitigating anti-TNF-induced attenuation of the immune response.

3.
Gastroenterology ; 162(7):S-596, 2022.
Article in English | EMBASE | ID: covidwho-1967340

ABSTRACT

Background: While vaccines against COVID-19 are effective in healthy individuals, we reported significantly lower serologic responses to BNT162b2 in patients with inflammatory bowel diseases (IBD) treated with anti-tumor necrosis factor (TNF) α agents. As this was apparent already 4 weeks post vaccination, vaccine longevity is concerning. Aim: to assess long-term serologic responses to BNT162b2 in patients with IBD stratified according to medical treatment. Methods: A prospective, observational multi-center Israeli study. Patients with IBD (anti-TNFα treated versus non-anti-TNFα treated) and healthy controls (HC) were followed from before the 1st BNT162b2 dose until 6 months after vaccination. COVID-19 spike (S) and nucleocapsid (N) antibodies (Abs) concentrations were analyzed by ELISA, followed by neutralization studies. Specific anti-receptor binding domain (RBD) memory Bcells response, serologic responses against variants of concern (VOCs), Beta, Gamma and Delta, immunoglobulin levels and lymphocyte cell subsets were evaluated as well. Safety was assessed using questionnaires, clinical and laboratory data. Results: Of 193 subjects, 130 had IBD (45 and 85 in the anti-TNFa and non-anti-TNFα groups, respectively), 63 HC. Serologic response assessed 176 (median) days (IQR 166-186) and compared to 4 weeks after 1st dose significantly declined in all three groups, but was lowest in the anti- TNFα group: 6 months anti-S Abs titer geometric means: 193 (95%CI: 128-292), 703 (520- 951), and 1253 (1023-1534) in anti-TNFα, non- anti-TNFα and HC groups, respectively, p<0.001, Figure 1. This was further supported by neutralization and inhibition studies. Importantly, significantly decreased memory B-cell response towards RBD was detected only in the anti-TNFα group, with the most significant reduction in response to Beta VOC (p<0.0008 and p<0.0001, vs. non-anti-TNFα and HC, respectively). Older age was an additional predictor of lower serologic response. Immunoglobulin levels and lymphocyte cell subsets were comparable between the study groups. Infection rate reflected by anti-N Abs was ~1% in all groups. Safety was comparable in all groups. Conclusion: The 6-months serologic response to BNT162b2 vaccine, evaluated prospectively, decreased in all subjects, most prominently in patients with IBD treated with anti-TNFα. Importantly, the latter also had the sharpest decline in serologies, the lowest functional activity and lowest RBD specific memory B-cells. Older age is an additional predictor of decreased serologic response. Altogether, waning of COVID-19 serologic and functional response over 6 months, specifically in patients with IBD treated with anti-TNFα, supports the need for an early third vaccine dose. (Figure Presented)

4.
Gastroenterology ; 162(7):S-278, 2022.
Article in English | EMBASE | ID: covidwho-1967264

ABSTRACT

Introduction: More adverse clinical outcomes following SARS-CoV-2 infection are reported in patients treated with infliximab/thiopurines (IFX/THIO), compared with biological monotherapy with anti-TNF or vedolizumab (VDZ). VDZ has been associated with a heightened and more durable serological response after infection and vaccination, compared to IFX. However, whether IBD patients on VDZ have a fully intact systemic response to SARS- CoV2 remains unknown. We explored the serological and functional neutralizing response after SARS-CoV-2 infection in IBD patients treated with VDZ, IFX or IFX/THIO compared to true healthy controls to guide treatment decisions and vaccination strategies. Methods: Serum from 640 IBD patients attending routine infusions in Oxford and London (May to December 2020) was screened by the Abbott assay for SARS-CoV-2 nucleocapsid (N) antibodies. Serum from seropositive patients was compared to seropositive health care workers (Table 1). Antibody reactivity to the SARS-CoV-2 wild type (WT) strain receptor-binding domain (RBD), full-length spike, and N was assayed by IgG/IgA ELISA over time as well as by IgG MSD V-PLEX ELISA at the time of seropositivity. A pseudotyped SARS-CoV-2 virus microneutralization assay was used to detect neutralizing antibodies to the WT, and an ELISA-based inhibition assay to compare differential inhibition of the WT vs. delta variant (DV) SARS-CoV-2 RBD-ACE2 interaction. Results: All IBD patients showed significantly reduced IgG antibody responses compared to healthy controls to all SARS-CoV-2 antigens, using MSD V-PLEX (Figure 1A-C). The greatest reduction in IgG response by ELISA was observed in patients treated with IFX/THIO (p=0.00019), whereas IgG response over time declined significantly faster in the IFX treated group (p=0.019). IgA responses were significantly reduced in the IFX/THIO group compared to healthy controls (p=0.009), but not in the IFX or VDZ group. The rate of decline in these monotherapy groups was not significantly different to healthy controls. Compared to healthy controls, functional SARS-CoV-2 neutralization was reduced in each treatment group (Figure 1D), with the greatest effect in patients receiving IFX/THIO (p=0.00000091). Neutralizing capacity to the DV was significantly reduced in 68.1% of IBD patients (30/44, p=0.0005). Conclusion: Both IFX and VDZ are associated with significantly reduced IgG responses to multiple SARS-CoV-2 antigens, and with impaired functional SARS-CoV-2 neutralizing antibody capacity, compared to healthy individuals. However, whilst IgG and neutralization responses are reduced in IBD patients on biological monotherapy, these findings were most pronounced in the combination treatment group. As neutralizing antibody responses are associated with protection, these observations may impact on decision-making regarding treatment and vaccination strategies.(Table Presented)(Figure Presented)

5.
Gastroenterology ; 162(7):S-277, 2022.
Article in English | EMBASE | ID: covidwho-1967262

ABSTRACT

Background: Although respiratory failure is the hallmark of severe disease, it is increasingly clear that Coronavirus Disease 2019 (COVID-19) is a multi-system disorder. The presence of gastrointestinal (GI) involvement by Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been suggested by epidemiological, clinical, non-human primate, in-vitro (enteroid) and ex-vivo (human biopsy) studies. Having recently documented persistence of SARS-CoV-2 within the intestinal epithelium 7 months after infection, here we aimed to study mucosal immune cell abnormalities in individuals with prior history of COVID-19. Methods: Individuals with previous COVID-19 diagnosis (by either RT–PCR or seroconversion) and controls (without RT-PCR or serological evidence of prior COVID-19 infection) undergoing endoscopic evaluation were recruited into the study (Table 1). Colonic and small intestinal (duodenal and ileal) biopsies were analyzed by multiparameter flow cytometry for mucosal immune cell populations including myeloid cells (classical and non-classical monocytes, dendritic cell subsets), T cells (subsets and activation state), B cells (including plasma cells) and NK cells. Persistence of viral antigens was determined by immunofluorescence microscopy (n=30) using a previously published anti-nucleocapsid (NP) antibody. Results: Thirty subjects with a previous history of COVID-19 (post-COVID), median of 4 months from diagnosis (range 1-10 months), were recruited and compared with 40 normal volunteer (NV) controls. Relative to controls, post-COVID subjects displayed higher frequencies of classical (CD14+) monocytes in both, the colon and the small bowel, while significantly higher frequencies of conventional dendritic cells (cDC)1 (lin-HLA-DRhiCD14- CD11c+CD141+) and cDC2 (lin-HLA-DRhiCD14-CD11c+CD1c+) were noted in the colon. Among NK subsets, CD56bright CD16- NK cells were significantly higher in the colon of post-COVID subjects. Among T cell subsets, CD8+ tissue resident memory T cells (CD8+CD69+CD103+) were significantly increased in colon of post-COVID subjects compared to NV. Among B cell subsets, plasma cells (CD3-CD27+CD38hi) trended higher (p= 0.06), while mucosal B cells (CD3-CD19+) were significantly lower in the terminal ileum of post-COVID subjects compared to NV. Finally, with IF, we detected SARS-CoV-2 NP in 10 out of 30 (33%) of post-COVID subjects (Figure 1). Conclusion: Innate and adaptive immune cell abnormalities persist in the intestinal mucosa of post-COVID subjects for up to 10 months and may reflect viral persistence or immune cell dysregulation in the intestines. These findings have major implications for understanding the pathogenesis of long-term sequelae of COVID-19, including long-haul COVID.(Table Presented)(Figure Presented)

6.
Arch Microbiol ; 204(8): 536, 2022 Aug 01.
Article in English | MEDLINE | ID: covidwho-1966133

ABSTRACT

The present study aimed to explore if bovine coronavirus nucleocapsid (BCoV N) impacts IFN-ß production in the host cells and to reveal further molecular mechanism of BCoV pathogenesis. Human embryonic kidney (HEK) 293 T cells were transiently transfected with pMyc-BCoV-N recombinant plasmids, then infected with the vesicular stomatitis virus (VSV). Expression levels of beta interferon (IFN-ß) mRNA were detected using RT-qPCR. The results showed that BCoV N gene was 1347 bp that was consistent with the expected size. pMyc-BCoV-N recombinant protein was 1347 bp which was successfully transcribed and overexpressed in HEK 293 T cells. BCoV-N recombinant protein inhibited dose-dependently VSV-induced IFN-ß production (p < 0.01). MDA5, MAVS, TBK1 and IRF3 could promote transcription levels of IFN-ß mRNA. But, BCoV-N protein demoted IFN-ß transcription levels induced by MDA5, MAVS, TBK1 and IRF3. Furthermore, expression levels of MDA5, MAVS, TBK1 and IRF3 mRNAs were reduced in RIG-I-like receptor (RLR) pathway. In conclusion, BCoV-N reduced IFN-ß levels in RIG-I-like receptor (RLR) pathway in HEK 293 T cells which were induced by MDA5, MAVS, TBK1 and IRF3(5D). BCoV-N protein inhibited IFN-ß production and activation of RIG-I-like receptors (RLRs) signal pathway. Our findings demonstrated BCoV N protein is an IFN-ß antagonist through inhibition of MDA5, MAVS, TBK1 and IRF3(5D) in RLRs pathway, also revealed a new mechanism of BCoV N protein to evade host innate immune response by inhibiting type I IFN production, which is beneficial to developing novel prevention strategy for BCoV disease in the animals and humans.


Subject(s)
Coronavirus, Bovine , Animals , Cattle , Coronavirus, Bovine/genetics , HEK293 Cells , Host-Pathogen Interactions , Humans , Interferon-beta/genetics , Nucleocapsid , RNA, Messenger , Recombinant Proteins
7.
Emerg Infect Dis ; 28(9)2022 Jul 22.
Article in English | MEDLINE | ID: covidwho-1963356

ABSTRACT

Given widespread use of spike antibody in generating coronavirus disease vaccines, SARS-CoV-2 nucleocapsid antibodies are increasingly used to indicate previous infection in serologic surveys. However, longitudinal kinetics and seroreversion are poorly defined. We found substantial seroreversion of nucleocapsid total immunoglobulin, underscoring the need to account for seroreversion in seroepidemiologic studies.

8.
Orv Hetil ; 163(25): 975-983, 2022 Jun 19.
Article in English | MEDLINE | ID: covidwho-1963096

ABSTRACT

INTRODUCTION: The COVID-19 (coronavirus disease 2019) caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is associated with high mortality rates worldwide. Polymerase chain reaction (PCR) is extensively used for virus detection in both infected patients and deceased persons. PCR, however, gives no information about the localization of the virus in cells and tissues. Detection of spike and nucleocapsid proteins and viral ribonucleic acid (RNA) of the SARS-CoV-2 in situ might provide more information and aid in the discovery of the pathomechanism of cellular damage. There are several commercially available anti-spike and anti-nucleocapsid antibodies used to detect immunohistochemical reactions, though each gives different results. OBJECTIVE: The goal of the present study was to compare the intensity and specificity of several anti-spike and anti-nucleocapsid antibodies in different dilutions in four Hungarian university departments. METHOD: Immunohistochemical reactions were performed on coded slides taken from infected lungs of 3 deceased and placenta samples with appropriate negative controls of formalin-fixed paraffin-embedded tissues, scanned, evaluated unanimously and analysed statistically by the assessors. RESULTS: By comparing the intensity, dilution, background and reproducibility of the different primary antibodies, it was possible to select the antibodies with the best results. CONCLUSION: The antibodies selected with established dilutions can be used in further studies to detect SARS-CoV-2 proteins in surgical materials and in samples obtained during autopsy. Orv Hetil. 2022; 163(25): 975-983.


Subject(s)
COVID-19 Testing , COVID-19 , SARS-CoV-2 , Antibodies, Viral , COVID-19/diagnosis , COVID-19 Testing/methods , Female , Humans , Nucleocapsid Proteins/analysis , Pregnancy , Reproducibility of Results , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/analysis
9.
Front Immunol ; 13: 871874, 2022.
Article in English | MEDLINE | ID: covidwho-1963450

ABSTRACT

The COVID-19 pandemic caused by the severe acute syndrome virus 2 (SARS-CoV-2) has been around since November 2019. As of early June 2022, more than 527 million cases were diagnosed, with more than 6.0 million deaths due to this disease. Coronaviruses accumulate mutations and generate greater diversity through recombination when variants with different mutations infect the same host. Consequently, this virus is predisposed to constant and diverse mutations. The SARS-CoV-2 variants of concern/interest (VOCs/VOIs) such as Alpha (B.1.1.7), Beta (B.1.351), Gamma (B.1.1.28/P.1), Delta (B.1.617.2), and Omicron (B.1.1.529) have quickly spread across the world. These VOCs and VOIs have accumulated mutations within the spike protein receptor-binding domain (RBD) which interacts with the angiotensin-2 converting enzyme (ACE-2) receptor, increasing cell entry and infection. The RBD region is the main target for neutralizing antibodies; however, other notable mutations have been reported to enhance COVID-19 infectivity and lethality. Considering the urgent need for alternative therapies against this virus, an anti-SARS-CoV-2 equine immunoglobulin F(ab')2, called ECIG, was developed by the Butantan Institute using the whole gamma-irradiated SARS-CoV-2 virus. Surface plasmon resonance experiments revealed that ECIG binds to wild-type and mutated RBD, S1+S2 domains, and nucleocapsid proteins of known VOCs, including Alpha, Gamma, Beta, Delta, Delta Plus, and Omicron. Additionally, it was observed that ECIG attenuates the binding of RBD (wild-type, Beta, and Omicron) to human ACE-2, suggesting that it could prevent viral entry into the host cell. Furthermore, the ability to concomitantly bind to the wild-type and mutated nucleocapsid protein likely enhances its neutralizing activity of SARS-CoV-2. We postulate that ECIG benefits COVID-19 patients by reducing the infectivity of the original virus and existing variants and may be effective against future ones. Impacting the course of the disease, mainly in the more vulnerable, reduces infection time and limits the appearance of new variants by new recombination.


Subject(s)
COVID-19 , SARS-CoV-2 , Angiotensin-Converting Enzyme 2/genetics , Animals , Antibodies, Viral , Horses , Humans , Nucleocapsid Proteins , Pandemics , Receptors, Virus/metabolism , Spike Glycoprotein, Coronavirus
10.
IEEE Sensors Journal ; : 1-1, 2022.
Article in English | Scopus | ID: covidwho-1961409

ABSTRACT

Current laboratory diagnostic approaches for virus detection give reliable results, but they require a lengthy procedure, trained personnel, and expensive equipment and reagents;hence, they are not a suitable choice for home monitoring purposes. This paper addresses this challenge by developing a portable impedimetric biosensing system for the identification of COVID-19 patients. This sensing system has two main parts: a throwaway two-working electrode (2-WE) strip and a novel read-out circuit, specifically designed for simultaneous signal acquisition from both working electrodes. Highly reliable electrochemical signal tracking from multiplex immunosensors provides a potential for flexible and portable multi-biomarker detection. The electrodes’surfaces were functionalized with SARS-CoV-2 Nucleocapsid Antibody enabling the selective detection of Nucleocapsid protein (N-protein) along with self-validation in the clinical nasopharyngeal swab specimens. The proposed programmable highly sensitive impedance read-out system allows for a wide dynamic detection range, which makes the sensor capable of detecting N-protein concentrations between 0.116 and 10,000 pg/mL. This lightweight and economical read-out arrangement is an ideal prospect for being mass-produced, especially during urgent pandemic situations. Also, such an impedimetric sensing platform has the potential to be redesigned for targeting not only other infectious diseases but also other critical disorders. IEEE

11.
J Infect Dis ; 2022 Jul 25.
Article in English | MEDLINE | ID: covidwho-1961056

ABSTRACT

Detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is essential for diagnosis, treatment, and infection control. Polymerase chain reaction (PCR) fails to distinguish acute from resolved infections, as RNA is frequently detected after infectiousness. We hypothesized that nucleocapsid in blood marks acute infection with the potential to enhance isolation and treatment strategies. In a retrospective serosurvey of inpatient and outpatient encounters, we categorized samples along an infection timeline using timing of SARS-CoV-2 testing and symptomatology. Among 1860 specimens from 1607 patients, the highest levels and frequency of antigenemia were observed in samples from acute SARS-CoV-2 infection. Antigenemia was higher in seronegative individuals and in those with severe disease. In our analysis, antigenemia exhibited 85.8% sensitivity and 98.6% specificity as a biomarker for acute coronavirus disease 2019 (COVID-19). Thus, antigenemia sensitively and specifically marks acute SARS-CoV-2 infection. Further study is warranted to determine whether antigenemia may aid individualized assessment of active COVID-19.

12.
Gastro Hep Adv ; 1(5): 844-852, 2022.
Article in English | MEDLINE | ID: covidwho-1959542

ABSTRACT

Background and Aims: Recent evidence suggests that the gut is an additional target for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, whether SARS-CoV-2 spreads via gastrointestinal secretions remains unclear. To determine the prevalence of gastrointestinal SARS-CoV-2 infection in asymptomatic subjects, we analyzed gastrointestinal biopsy and liquid samples from endoscopy patients for the presence of SARS-CoV-2. Methods: We enrolled 100 endoscopic patients without known SARS-CoV-2 infection (cohort A) and 12 patients with a previous COVID-19 diagnosis (cohort B) in a cohort study performed at a regional hospital. Gastrointestinal biopsies and fluids were screened for SARS-CoV-2 by polymerase chain reaction (PCR), immunohistochemistry, and virus isolation assay, and the stability of SARS-CoV-2 in gastrointestinal liquids in vitro was analyzed. Results: SARS-CoV-2 ribonucleic acid was detected by PCR in the colonic tissue of 1/100 patients in cohort A. In cohort B, 3 colonic liquid samples tested positive for SARS-CoV-2 by PCR and viral nucleocapsid protein was detected in the epithelium of the respective biopsy samples. However, no infectious virions were recovered from any samples. In vitro exposure of SARS-CoV-2 to colonic liquid led to a 4-log-fold reduction of infectious SARS-CoV-2 within 1 hour (P ≤ .05). Conclusion: Overall, the persistent detection of SARS-CoV-2 in endoscopy samples after resolution of COVID-19 points to the gut as a long-term reservoir for SARS-CoV-2. Since no infectious virions were recovered and SARS-CoV-2 was rapidly inactivated in the presence of colon liquids, it is unlikely that performing endoscopic procedures is associated with a significant infection risk due to undiagnosed asymptomatic or persistent gastrointestinal SARS-CoV-2 infections.

13.
British Journal of Dermatology ; 186(6):e254, 2022.
Article in English | EMBASE | ID: covidwho-1956702

ABSTRACT

The COVID-19 pandemic resulted in a rapid requirement for a safe and effective vaccination programme. Currently, three types of vaccines exist: mRNA (Pfizer), adenoviral vector (AstraZeneca) and inactivated whole-virus vaccines (Sinofarm). These all have reported cutaneous side-effects, including papulovesicular, pityriasis rosea-like and papulosquamous eruptions (McMahon DE, Kovarik CL, Damsky W et al. Clinical and pathologic correlation of cutaneous COVID-19 vaccine reactions including V-REPP: a registry-based study. J Am Acad Dermatol 2021;86: 113-21). We present a case of delayed type III hypersensitivity reaction clinically resembling urticarial vasculitis (UV) in a 66-year-old woman following AstraZeneca vaccine. She initially reported urticarial lesions on the hands after the first vaccination;these settled spontaneously. On subsequent vaccination she developed a florid rash 4 days later, presenting to Accident & Emergency with angio-oedema, malaise and urticaria. The eruption was presumed viral given the mildly elevated C-reactive protein, and negative lateral flow test for COVID-19. She was given fexofenadine 180 mg QDS for 6 weeks;however, the rash persisted and became more widespread over the following 4 weeks. The initial urticated wheals persisted >24 h, becoming bruise-like and painful. Skin biopsy confirmed UV. ANA, complement, ANCA and COVID-19 polymerase chain reaction were nonsignificant. We believe this is the first documented case of UV triggered by the AstraZeneca vaccine and the third case of UV following a Sars-CoV-2 vaccine reported in English literature. The two other cases were secondary to Pfizer and whole-virus vaccine, respectively. From the literature it is believed UV is potentially caused by the coronavirus particles rather than vaccine additives, as the Sars-CoV-2 nucleocapsid has been demonstrated in skin lesions of asymptomatic COVID-19 patients with UV (Criado PR, Criado RFJ, Gianotti R et al. Urticarial vasculitis revealing immunolabelled nucleocapsid protein of SARS-CoV-2 in two Brazilian asymptomatic patients: the tip of the COVID-19 hidden iceberg? J Eur Acad Dermatol Venereol 2021;35: e563-6). Thus, although rare, clinicians should be aware of this entity.

14.
Int J Mol Sci ; 23(15)2022 Jul 23.
Article in English | MEDLINE | ID: covidwho-1957346

ABSTRACT

The relentless, protracted evolution of the SARS-CoV-2 virus imposes tremendous pressure on herd immunity and demands versatile adaptations by the human host genome to counter transcriptomic and epitranscriptomic alterations associated with a wide range of short- and long-term manifestations during acute infection and post-acute recovery, respectively. To promote viral replication during active infection and viral persistence, the SARS-CoV-2 envelope protein regulates host cell microenvironment including pH and ion concentrations to maintain a high oxidative environment that supports template switching, causing extensive mitochondrial damage and activation of pro-inflammatory cytokine signaling cascades. Oxidative stress and mitochondrial distress induce dynamic changes to both the host and viral RNA m6A methylome, and can trigger the derepression of long interspersed nuclear element 1 (LINE1), resulting in global hypomethylation, epigenetic changes, and genomic instability. The timely application of melatonin during early infection enhances host innate antiviral immune responses by preventing the formation of "viral factories" by nucleocapsid liquid-liquid phase separation that effectively blockades viral genome transcription and packaging, the disassembly of stress granules, and the sequestration of DEAD-box RNA helicases, including DDX3X, vital to immune signaling. Melatonin prevents membrane depolarization and protects cristae morphology to suppress glycolysis via antioxidant-dependent and -independent mechanisms. By restraining the derepression of LINE1 via multifaceted strategies, and maintaining the balance in m6A RNA modifications, melatonin could be the quintessential ancient molecule that significantly influences the outcome of the constant struggle between virus and host to gain transcriptomic and epitranscriptomic dominance over the host genome during acute infection and PASC.


Subject(s)
COVID-19 , Melatonin , Host-Pathogen Interactions , Humans , RNA, Viral , SARS-CoV-2 , Virus Replication
15.
Clin Pract ; 12(4): 579-590, 2022 Jul 26.
Article in English | MEDLINE | ID: covidwho-1957242

ABSTRACT

It is an acknowledged fact that SARS-CoV-2 exhibits tropism for the human placenta. A possible mechanism of SARS-CoV-2 entry into host cells is via angiotensin-converting enzyme 2 (ACE2) receptors, which are expressed in trophoblasts, endothelial cells, and macrophages. The present study describes a case of spontaneous miscarriage in the 20th gestational week after maternal SARS-CoV-2 infection. The placenta and various fetal organs were examined for structural alterations and expression of the viral nucleocapsid protein and several immune cell markers via immunohistochemistry (IHC). Histopathological examination of the placenta revealed acute chorioamnionitis, acute subamnionic placentitis, multiple intervillous thrombi, increased fibrinoid deposition, and necrotic changes of the chorionic villi. Immunohistochemistry confirmed the presence of SARS-CoV-2 nucleocapsid protein regions predominantly in the syncytiotrophoblast. Staining of the placental tissue for different markers helped elucidate the distribution of immune cells. Pathomorphological examination of the fetal organs demonstrated changes in microcirculation with the presence of sludge phenomenon and diapedesis haemorrhages, mostly in the lungs, brain, and myocardium. IHC staining of fetal organs revealed expression of SARS-CoV-2 nucleocapsid protein, which was detected to the highest extent in the brain, lungs, and liver. The findings of the present report support the hypothesis of possible vertical transmission of SARS-CoV-2 from mother to fetus.

16.
Diagnostics (Basel) ; 12(5)2022 May 21.
Article in English | MEDLINE | ID: covidwho-1953133

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant outbreaks have highlighted the need of antigen-detecting rapid diagnostic tests (Ag-RDTs) that can be used at the point-of-care (POC). Although many Ag-RDTs have been approved for SARS-CoV-2 detection, studies demonstrating the clinical performance of Ag-RDTs against variants of concern, especially the new Omicron variant, are limited. The aim of this study was to evaluate the diagnostic sensitivity and specificity of the AMAZING COVID-19 Antigen Sealing Tube Test Strip (Colloidal Gold) in 584 early symptomatic and asymptomatic participants (age range 0-90 years). The performance of this Ag-RDT was assessed by comparing its results with reverse transcription RT-PCR (rRT-PCR). One hundred twenty positive samples were also analyzed with rRT-PCR to discriminate Omicron and Delta/Kappa variants (72.50% Omicron; 27.50% Delta/Kappa). Overall, the Ag-RDT showed high positive and negative percent values of 92.52% (95% CI, 86.61-95.95%) and 98.05% (95% CI, 96.41-98.95%), respectively, as well as an overall diagnostic accuracy of 96.92% (95% CI, 95.17-98.16%). Taken together, these data indicate that this inexpensive and simple-to-use Ag-RDT presents excellent analytical performance and can reliably detect Omicron and Delta/Kappa variants.

17.
Front Microbiol ; 13: 853410, 2022.
Article in English | MEDLINE | ID: covidwho-1952413

ABSTRACT

Human coronavirus HKU1 (HCoV-HKU1) is one of the four endemic coronaviruses. It has been suggested that there is a difference in incidence, with PCR-confirmed HCoV-NL63 and HCoV-OC43 infections occurring more commonly, whereas HCoV-HKU1 is the least seen. Lower incidence of HCoV-HKU1 infection has also been observed in serological studies. The current study aimed to investigate antibody dynamics during PCR-confirmed HCoV-HKU1 infections using serum collected during infection and 1 month later. We expressed a new HCoV-HKU1 antigen consisting of both the linker and carboxy-terminal domain of the viral nucleocapsid protein and implemented it in ELISA. We also applied a spike-based Luminex assay on serum samples from PCR-confirmed infections by the four endemic HCoVs. At least half of HCoV-HKU1-infected subjects consistently showed no antibody rise via either assay, and some subjects even exhibited substantial antibody decline. Investigation of self-reported symptoms revealed that HCoV-HKU1-infected subjects rated their illness milder than subjects infected by other HCoVs. In conclusion, HCoV-HKU1 infections reported in this study displayed atypical antibody dynamics and milder symptoms when compared to the other endemic HCoVs.

18.
Biophys Chem ; 288: 106843, 2022 09.
Article in English | MEDLINE | ID: covidwho-1944353

ABSTRACT

The nucleocapsid protein of the SARS-CoV-2 virus comprises two RNA-binding domains and three regions that are intrinsically disordered. While the structures of the RNA-binding domains have been solved using protein crystallography and NMR, current knowledge of the conformations of the full-length nucleocapsid protein is rather limited. To fill in this knowledge gap, we combined coarse-grained molecular simulations with data from small-angle X-ray scattering (SAXS) experiments using the ensemble refinement of SAXS (EROS) method. Our results show that the dimer of the full-length nucleocapsid protein exhibits large conformational fluctuations with its radius of gyration ranging from about 4 to 8 nm. The RNA-binding domains do not make direct contacts. The disordered region that links these two domains comprises a hydrophobic α-helix which makes frequent and nonspecific contacts with the RNA-binding domains. Each of the intrinsically disordered regions adopts conformations that are locally compact, yet on average, much more extended than Gaussian chains of equivalent lengths. We offer a detailed picture of the conformational ensemble of the nucleocapsid protein dimer under near-physiological conditions, which will be important for understanding the nucleocapsid assembly process.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Nucleocapsid , Nucleocapsid Proteins/chemistry , Protein Conformation , Scattering, Small Angle , X-Ray Diffraction
19.
IEEE J Sel Top Signal Process ; 16(2): 164-174, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1948819

ABSTRACT

This work presents an opto-electrical method that measures the viral nucleocapsid protein and anti-N antibody interactions to differentiate between SARS-CoV-2 negative and positive nasal swab samples. Upon light exposure of the patient nasal swab sample mixed with the anti-N antibody, charge transfer (CT) transitions within the altered protein folds are initiated between the charged amino acids side chain moieties and the peptide backbone that play the role of donor and acceptor groups. A Figure of Merit (FOM) was introduced to correlate the relative variations of the samples with and without antibody at two different voltages. Empirically, SARS-CoV-2 in patient nasal swab samples was detected within two minutes, if an extracted FOM threshold of >1 was achieved; otherwise, the sample wasconsidered negative.

20.
Journal of Mazandaran University of Medical Sciences ; 32(210):26-36, 2022.
Article in Arabic | EMBASE | ID: covidwho-1935328

ABSTRACT

Background and purpose: Coronavirus disease 2019 (COVID-19) is a respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, an indirect ELISA method was designed to measure the human IgM and IgG antibodies against SARS-CoV-2. Materials and methods: Protein sequence of nucleocapsid antigen from SARS-CoV-2 was expressed in E. coli BL21 and then was purified by chromatography. The purified protein was confirmed by SDS-PAGE and Western blotting. An indirect ELISA method was designed to measure the specific IgG and IgM antibodies against SARS-CoV-2 using recombinant N protein. The optimized ELISA method was then applied to measure the IgG and IgM antibodies in 61 infected or recovered COVID-19 patients and in 31 healthy controls. Finally, data obtained from the designed ELISA method were compared with those of a commercially approved ELISA kit. Results: The recombinant nucleocapsid protein was successfully expressed and purified which was confirmed by SDS-PAGE and Western blotting. The amount of optical densities obtained from the designed ELISA method was similar to those of the commercial kit in 61 patients and 31 controls. The sensitivity and specificity of the designed ELISA method for IgG were 100% compared with the commercial ELISA kit, while the sensitivity and specificity for IgM were 96.72 and 96.77, respectively. Conclusion: Serological tests alone are not suitable for diagnosis;however, their combination with molecular tests increases the accuracy and sensitivity of the COVID-19 diagnosis. These tests are also vauable for epidemiological studies.

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