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1.
ACS Nano ; 2022 Aug 03.
Article in English | MEDLINE | ID: covidwho-1972517

ABSTRACT

The elucidation of viral-receptor interactions and an understanding of virus-spreading mechanisms are of great importance, particularly in the era of a pandemic. Indeed, advances in computational chemistry, synthetic biology, and protein engineering have allowed precise prediction and characterization of such interactions. Nevertheless, the hazards of the infectiousness of viruses, their rapid mutagenesis, and the need to study viral-receptor interactions in a complex in vivo setup call for further developments. Here, we show the development of biocompatible genetically engineered extracellular vesicles (EVs) that display the receptor binding domain (RBD) of SARS-CoV-2 on their surface as coronavirus mimetics (EVsRBD). Loading EVsRBD with iron oxide nanoparticles makes them MRI-visible and, thus, allows mapping of the binding of RBD to ACE2 receptors noninvasively in live subjects. Moreover, we show that EVsRBD can be modified to display mutants of the RBD of SARS-CoV-2, allowing rapid screening of currently raised or predicted variants of the virus. The proposed platform thus shows relevance and cruciality in the examination of quickly evolving pathogenic viruses in an adjustable, fast, and safe manner. Relying on MRI for visualization, the presented approach could be considered in the future to map ligand-receptor binding events in deep tissues, which are not accessible to luminescence-based imaging.

2.
Letters in Drug Design and Discovery ; 19(11):996-1006, 2022.
Article in English | EMBASE | ID: covidwho-1968943

ABSTRACT

Background: The 2019 novel coronavirus disease (COVID-19) has caused a global health catastrophe by affecting the human population around the globe. Unfortunately, there is no specific medi-cation or treatment currently available for COVID-19. Objective: It is extremely important to find effective drug treatment in order to put an end to this pandemic period and return to normal daily life. In this context and considering the urgency, rather than focusing on the discovery of novel compounds, it is critical to explore the effects of existing herbal agents with proven antiviral properties on the virus. Methods: Molecular docking studies were carried out employing three different methods, Glide extra precision (XP) docking, induced fit docking (IFD), and molecular mechanics/generalized born surface area (MM/GBSA), to determine the potential antiviral and antibacterial effects of 58 phytochemicals present in Rosmarinus officinalis, Thymbra spicata, Satureja thymbra, and Stachys lavandulifolia plants against the main protease (Mpro) and angiotensin-converting enzyme 2 (ACE2) enzymes. Results: 7 compounds stood out among all the molecules, showing very high binding affinities. Accord-ing to our findings, the substances chlorogenic acid, rosmarinic acid, and rosmanol exhibited extremely significant binding affinities for both Mpro and ACE2 enzymes. Furthermore, carnosic acid and alpha-cadinol showed potent anti-Mpro activity, whereas caffeic acid and carvacrol exhibited promising anti-ACE2 activity. Conclusion: Chlorogenic acid, rosmarinic acid, rosmanol, carnosic acid, alpha-cadinol, caffeic acid, and carvacrol compounds have been shown to be powerful anti-SARS-CoV-2 agents in docking simulations against Mpro and ACE2 enzymes, as well as ADME investigations.

3.
Natural Product Communications ; 17(7), 2022.
Article in English | EMBASE | ID: covidwho-1968415

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was initially reported in the Wuhan province of China, spread throughout the world, and caused massive destruction in the form of a global pandemic that started back in 2020. SARS-CoV-2 is an RNA virus with various proteins like main protease, spike protein, NSP15 endoribonuclease, RNA-dependent RNA polymerase, and papain-like protease targeted to screen and find the novel drug candidate that can potentially work against the virus. Previous studies have reported multiple drugs after screening and validation against a single target and reported multiple medications. Nevertheless, many drugs are being used to date but do not have enough potential to work against SARS-CoV-2 and curb the spread and death rate. In this study, with the hypothesis of 1 drug and multiple targets, we have taken 5 main target proteins and screened the Asinex's complete BioDesign library (1,70,269 compounds) and identified N-{2-[(2S)-2-Amino-3-methylbutoxy]-6-propylbenzoyl}-L-phenylalanyl-L-serine (Butoxypheser) as multitarget inhibitor against SARS-CoV-2. Also, Butoxypheser has shown excellent docking scores, hydrogen bonding, and other bonding configurations like van der Waals force and water bridges. The stability and interaction pattern of the compound was validated with structural interaction fingerprints (SIFts) and molecular dynamics (MD) simulation. The Butoxypheser has performed flawlessly throughout the study, and the same results were used to compare the compound's activity against multiple targets. After a thorough theoretical comparative analysis, Butoxypheser can be treated as a multitargeted inhibitor candidate against SARS-CoV-2. Further, this study needs to be validated experimentally before human use.

4.
Scandinavian Journal of Immunology ; 95(6), 2022.
Article in English | EMBASE | ID: covidwho-1968192

ABSTRACT

The COVID-19 pandemic has had a dramatic effect on the quality of life worldwide. It is caused by the SARS-CoV-2 virus and the main symptoms include myalgia, headache, and non-productive cough. Tocilizumab (TCZ) is a monoclonal antibody antagonist for the Interleukin-6 (IL-6) receptor. TCZ has shown significant efficacy in patients with severe COVID-19 because of the upregulation of IL-6 in their serum that has a correlation to severe disease and mortality. Here, we show how levels of IL-6 in serum of TCZ treated COVID-19 patients in the intensive care unit (ICU) is elevated in response to the TCZ treatment. Five COVID-19 patients that were administered TCZ in the ICU had serum samples taken at least two timepoints, before and after TCZ administration. Serum cytokine and antibody levels were analysed by multiplex. The study was approved by The National Bioethics Committee (VSN-20-169) and the Data Protection Authority. As expected, all ICU patients were in cytokine storm with significantly high levels of various inflammatory mediators including IL-6 (ranging from 4-196 pg/ml) before TCZ administration. Interestingly, despite of overall clinical improvements TCZ administration led to a significant surge of IL-6 levels, resulting in a 213-fold increase after treatment (range from 1940-9067 pg/ml). In contrast to IL-6 none of the other inflammatory biomarkers had the same pattern. However, IL-10 was downregulated in 4/5 individuals. Finally, all patients demonstrated normal antibody response in addition to high IgA levels against receptor binding domain and spike 1. These findings demonstrate that receptor blockage of cytokines can lead to a significant surge of its corresponding cytokine with unclear, but potentially important clinical significance.

5.
Zeitschrift fur Phytotherapie ; 43:S46, 2022.
Article in English | EMBASE | ID: covidwho-1967698

ABSTRACT

Introduction SARS-CoV-2 variants of concern (VOCs) represent an alarming threat as they may escape vaccination effectiveness. Broad-spectrum antivirals could complement and further enhance preventive benefits achieved through SARS-CoV-2 vaccination campaigns. Aim Testing the antiviral activity of Echinacea purpurea against VOCs and exploring underlying modes-of-action. Method A hydroethanolic extract of freshly harvested E. purpurea herb and roots (Echinaforce®, EF extract) was tested to inhibit infection of VOCs B1.1.7 (alpha), B.1.351.1 (beta), P.1 (gamma), B1.617.2 (delta), AV.1 (Scottish) and B1.525 (eta). Molecular dynamics (MD) were used to study interaction of EF phytochemical markers with known pharmacological viral and host cell targets. Results EF broadly inhibited propagation of all tested SARS-CoV-2 VOCs at EC50 < 12.0 ;jg/ml. Treatment of epithelial cells with 20 jg/ml EF prevented sequential infection with SARS-CoV-2 (Hu-1). MD analyses showed for alkylamides, caftaric acid and feruoyl-tartaric constant binding affinity to spike proteins of all VOCs and to TMPRSS-2, a serine protease required for virus endocytosis. Conclusion EF extract exhibits virucidal activity against all tested SARS-CoV-2 VOCs and protects epithelial cells from infection.

6.
Sensors (Basel) ; 22(15)2022 Jul 29.
Article in English | MEDLINE | ID: covidwho-1969429

ABSTRACT

The coronavirus pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has accelerated the development of biosensors based on new materials and techniques. Here, we present our effort to develop a fast and affordable optical biosensor using photoluminescence spectroscopy for anti-SARS-CoV-2 antibody detection. The biosensor was fabricated with a thin layer of the semiconductor polymer Poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-2,2'-bithiophene-5,5'-diyl)] (F8T2) as a signal transducer material. We mounted the biosensors by depositing a layer of F8T2 and an engineered version of RBD from the SARS-CoV-2 spike protein with a tag to promote hydrophobic interaction between the protein and the polymeric surface. We validated the biosensor sensitivity with decreasing anti-RBD polyclonal IgG concentrations and challenged the biosensor specificity with human serum samples from both COVID-19 negative and positive individuals. The antibody binding to the immobilized antigen shifted the F8T2 photoluminescence spectrum even at the low concentration of 0.0125 µg/mL. A volume as small as one drop of serum (100 µL) was sufficient to distinguish a positive from a negative sample without requiring multiple washing steps and secondary antibody reactions.


Subject(s)
Biosensing Techniques , COVID-19 , Communicable Diseases , Antibodies, Viral , Biosensing Techniques/methods , COVID-19/diagnosis , Humans , Polymers , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
8.
Front Immunol ; 13: 891816, 2022.
Article in English | MEDLINE | ID: covidwho-1969020

ABSTRACT

An important number of studies have been conducted on the potential association between human leukocyte antigen (HLA) genes and COVID-19 susceptibility and severity since the beginning of the pandemic. However, case-control and peptide-binding prediction methods tended to provide inconsistent conclusions on risk and protective HLA alleles, whereas some researchers suggested the importance of considering the overall capacity of an individual's HLA Class I molecules to present SARS-CoV-2-derived peptides. To close the gap between these approaches, we explored the distributions of HLA-A, -B, -C, and -DRB1 1st-field alleles in 142 Iranian patients with COVID-19 and 143 ethnically matched healthy controls, and applied in silico predictions of bound viral peptides for each individual's HLA molecules. Frequency comparison revealed the possible predisposing roles of HLA-A*03, B*35, and DRB1*16 alleles and the protective effect of HLA-A*32, B*58, B*55, and DRB1*14 alleles in the viral infection. None of these results remained significant after multiple testing corrections, except HLA-A*03, and no allele was associated with severity, either. Compared to peptide repertoires of individual HLA molecules that are more likely population-specific, the overall coverage of virus-derived peptides by one's HLA Class I molecules seemed to be a more prominent factor associated with both COVID-19 susceptibility and severity, which was independent of affinity index and threshold chosen, especially for people under 60 years old. Our results highlight the effect of the binding capacity of different HLA Class I molecules as a whole, and the more essential role of HLA-A compared to HLA-B and -C genes in immune responses against SARS-CoV-2 infection.


Subject(s)
COVID-19 , Histocompatibility Antigens Class I , Viral Proteins , COVID-19/genetics , HLA-A Antigens/genetics , HLA-A Antigens/metabolism , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/metabolism , Humans , Iran , Middle Aged , Protein Binding , SARS-CoV-2 , Viral Proteins/metabolism
9.
Journal of Hepatology ; 77:S240-S241, 2022.
Article in English | EMBASE | ID: covidwho-1967503

ABSTRACT

Background and aims: Canada is currently on target to reach the 2030 WHO goal of HCV elimination. Continued high rates of treatment initiation are required to meet this goal. Novel models have proven successful to engage populations who use drugs (PWUD) in HCV therapy with a simplified, task-shifted cascade of care: Tayside, Scotland pharmacy-based HCV screening and treatment has demonstrated excellent outcomes and progress towards local HCV elimination. The EPIC Study seeks to determine whether pharmacybased treatment successes can be replicated at community pharmacies in Victoria BC. Method: Four community pharmacies known to work with PWUD and provide opioid agonist therapy (OAT) were provided training sessions to equip staff with a standardized tool kit of resources. In fall 2020, pharmacy staff were trained to provide verbal informed consent and perform point of care HCV OraQuick antibody screening. Pharmacies were supported by a study nurse to link to HCV RNA testing when antibody positive patients were identified, with initiation of HCV treatment offered to those found to be RNA positive. (Figure Presented) Figure: (: THU296): Antibody responses after the COVID-19 vaccination in patients with AILD and healthy controls. (A-B) The seropositivity rate (A) and titers (B) of anti-RBD-IgG in patients with AILD and healthy controls. (D-E) The seropositivity rate (D) and titers (E) of NAbs in patients with AILD and healthy controls. The distribution of anti-RBD-IgG (C) and NAbs (F) antibody titers over time in patients with AILD and healthy controls. AILD, autoimmune liver disease;anti-RBD-IgG, spike receptor-binding domain IgG antibody;NAbs, neutralizing antibodies. The study nurse worked with pharmacy staff to strategize adherence and support as needed by study subjects. Qualitative interviews have been conducted with five pharmacy staff to explore their experiences with testing and monitoring HCV treatment and the feasibility of involving pharmacists in the HCV care cascade. Results: To date pharmacy staff completed 171 HCV OraQuick tests finding 53 tested positive for HCV antibodies: 23 people were HCV RNA negative, (20 previously treated and 2 self-cleared), 8 unk/LTF. Of the 22 RNA positive participants, 1 is pending treatment start, 21 people have started treatment, with 8 achieving SVR. While great success has been achieved in treating identified people, less than half of projected OraQuick tests have been completed. Although the onset of the Covid 19 pandemic was a fundamental barrier incorporating HCV testing at pharmacies, stigma related to HCV and illicit drug use continues to impact this process. Pharmacists described feeling hesitant about approaching participants, especially after receiving negative responses from clients about HCV testing. Some worried their relationship would change with clients as asking about HCV implied risky drug use. Conclusion: This innovative and novel approach to HCV therapy in PWUD attempted to use a pharmacy-based approach to find people with limited connection to primary health care to test and treat HCV. Increased training of pharmacy staff related to stigma around drug use and HCV is required both before and ongoing for successful integration of pharmacy-led HCV testing and treatment in Canada.

10.
Gastroenterology ; 162(7):S-1252, 2022.
Article in English | EMBASE | ID: covidwho-1967442

ABSTRACT

Introduction: Limited data exist on the immunogenicity of SARS-CoV-2 vaccination in liver transplant (LT) recipients. Homologous vaccination protocol demonstrated suboptimal responses in this population. Several studies showed that heterologous prime-boost approach yielded a better seroconversion rate in healthy individuals. We, therefore, aimed to explore the immunogenicity and safety of heterologous prime-boost immunization with ChAdOx1 nCoV-19 AstraZeneca (AZ) and BNT162b2 Pfizer-BioNTech (BNT) among LT patients. Method: LT recipients receiving SARS-CoV-2 vaccine at King Chulalongkorn Memorial Hospital between April and November 2021 were consecutively enrolled. Patients received either heterologous prime-boost protocol (AZ/BNT) or homologous regimen (AZ/AZ) depending on national policies. Blood samples were collected before vaccine administration and 4 weeks after the second dose. SARS-CoV-2 spike receptor-binding-domain (RBD) IgG was measured using electrochemiluminescence immunoassay (Roche). A titer $100 U/mL was considered as a protective antibody. The neutralizing antibody was detected by enzymelinked immunosorbent assay-based surrogate virus neutralization test (sVNT) (GenScript) with positive cut-off of ≥30% inhibition. Adverse events (AEs) within 7 days following vaccination were recorded by questionnaires. Results: Eighty-nine LT recipients were enrolled. Of these, 64 (71.9%) and 25 (28.1%) patients received AZ/BNT and AZ/AZ, respectively. Majority was male (68.5%) with mean age of 58.3±14.5 years. Median time since transplant was 5.7 years (IQR 2.8-11.8). No patient had a previous diagnosis of SARSCoV- 2 infection. Comparable seroconversion rate of anti-RBD antibody and sVNT after vaccination were observed in both AZ/BNT and AZ/AZ groups (70.3% vs 64.0%, p=0.62 and 77.8% vs 59.1%, p=0.10, respectively). However, median IgG titer was significantly higher in AZ/BNT group compared to AZ/AZ group (842.9 U/mL vs 152.2 U/mL, p=0.011). Patients receiving AZ/BNT also had significantly higher sVNT levels than those receiving AZ/BNT (91.2% vs 35.8%, p=0.003) (Figure 1). In multivariate analysis, use of prednisolone (OR 6.3, 95%CI 1.1-35.4, p=0.036) and LT duration <5 years (OR 3.2, 95%CI 1.1-9.1, p= 0.029) were associated with lack of protective serological response. AZ/BNT regimen trended to have higher reported AEs than AZ/AZ (Figure 2). No graft rejection or serious AEs were found. Conclusion: Heterologous prime-boost regimen with adenoviral vectored and mRNA SARS-CoV-2 vaccine yielded greater humoral response than homologous protocol and was well-tolerated in LT recipients. T-cell response, which might play additional role in protection, and immune durability of this mix-and-match strategy are eagerly awaited. (Figure Presented)

11.
Gastroenterology ; 162(7):S-1008, 2022.
Article in English | EMBASE | ID: covidwho-1967396

ABSTRACT

BACKGROUND: Immune-modulating medications for inflammatory bowel diseases (IBD) have been associated with suboptimal vaccine responses. There is conflicting data with SARS-CoV-2 vaccination. METHODS: We measured SARS-CoV-2 vaccine immunogenicity at 2 weeks post 2nd mRNA vaccine in IBD patients as compared to normal healthy donors (NHD). We measured humoral immune responses to SARS-CoV-2: anti-spike Immunoglobulin G (IgG) and anti-receptor binding domain (RBD) IgG were measured by ELISA, and neutralizing antibody titers were measured using recombinant, reporter SARS-CoV-2. Antigen specific memory B cells were measured using recombinant SARS-CoV-2 proteins. Activation induced marker T cell (AIM) assays were performed using SARS-CoV-2 spike megapools. Immunophenotyping was performed by flow cytometry. RESULTS: We enrolled 29 patients with IBD (19 with Crohn's disease, 10 with ulcerative colitis) on infliximab (IFX) monotherapy (N=9), IFX combination therapy with a thiopurine (N=9), vedolizumab monotherapy (N= 11) as compared to matched NHD (N=12). At 2 weeks post vaccination, all subjects made detectable anti-spike IgG and anti-RBD IgG. There were no differences in anti-spike IgG titers among the different groups. IBD patients on IFX monotherapy, but not IBD patients on IFX combination therapy or vedolizumab monotherapy, had lower anti-RBD and neutralization titers as compared to NHD (p-value: 0.041 and 0.023, respectively) (Fig. 1). There were no significant differences in the percentage of spike-specific or RBD-specific memory B cells in IBD patients as compared to NHD (Fig. 1). There were no differences in the percentage of spike-specific CD4+ or CD8+ T cells in all IBD patients as compared to NHDs (Fig. 2). CONCLUSIONS: We demonstrate overall comparable and perserved cell-mediated immunity to SARS-CoV-2 vaccination in a small cohort of IBD patients treated with a range of different immune-modulating medications as compared to healthy controls. Larger numbers of patients are needed to validate these findings.

12.
Gastroenterology ; 162(7):S-1004, 2022.
Article in English | EMBASE | ID: covidwho-1967388

ABSTRACT

BACKGROUND: The characteristics of SARS-CoV-2 vaccine-induced immunity in inflammatory bowel disease (IBD) patients on immune modifying agents has not been clearly defined due to their exclusion in vaccine trials. Emerging results suggest infliximab impairs antibody response compared to vedolizumab. However there has not been direct comparison to controls. We evaluated this with both humoral and T cell response in IBD patients. METHODS: Antibody and T cell response were analysed in IBD patients who received BNT162b2 (Pfizer–BioNTech) or ChAdOx1 nCoV-19 (Oxford–AstraZeneca) vaccination from a single Australian centre. The control group were healthcare workers (HCW) without IBD. Blood samples were taken at 4 time points: at baseline V0 (before vaccination);V1 (7- 14 days after vaccine 1);V2 (7-14 days after vaccine 2);V3 (21-42 days after vaccine 2). Antibodies to the S1/2 IgG subunit and receptor-binding protein (RBD) were measured and reported here. RESULTS: 88 (28 ulcerative colitis, 50 Crohn's disease) IBD patients were included and compared to 53 healthy controls (Table 1). IBD patients medications included 6 5ASA (6.8%), 6 immunomodulator monotherapy (6.8%), 14 anti-TNF monotherapy (15.9%), 32 anti-TNF combination therapy with immunomodulator (36%), 16 IL12/23 (18%) and 13 vedolizumab (14%). Pre-vaccine baseline sera showed absence of anti-RBD antibodies in all participants. 84 patients (87%) received BNT162b2 and 4 (4.5%) received ChAdOx1 nCoV-19 vaccines. Geometric mean [SD] anti-S1/2 antibody concentrations at 4 weeks after second vaccination (V3) were significantly lower in IBD TNF treated patients (162.6[1.7]) compared to IBD non TNF treated patients (325.2[1.3]), and healthy controls (325.2[1.3]), p<0.0001 (Figure 1). There was no difference between non-TNF treated patients including those on vedolizumab or IL12/23 compared to controls. Similarly there was a significant difference between anti-RBD IgG titres between TNF and non-TNF IBD patients at V3 but not when compared to controls. There was no difference in RBD IgG and anti-S1/2 antibodies between anti-TNF monotherapy and combination therapy. All healthy controls and most IBD patients seroconverted at V3. 2 patients that failed to seroconvert were on steroid. CONCLUSION: TNF agents influence SARS-CoV-2 vaccine-induced antibody response in IBD patients, with lower anti-S1/2 IgG concentrations compared to non-TNF IBD patients and healthy controls. However, there was no difference in RBD IgG concentrations. It is unclear whether these subtle differences in antibody response in IBD patients on TNF agents is biologically meaningful, as most seroconverted after second dose vaccination. They may translate to differences in antibody longevity, but this is yet to be demonstrated. Neutralising antibody and T cell (CD4+/CD8+/follicular T cell) data from this study to come. (Table Presented) (Figure Presented)

13.
Gastroenterology ; 162(7):S-598-S-599, 2022.
Article in English | EMBASE | ID: covidwho-1967344

ABSTRACT

Background: Current recommendations in many countries support additional COVID-19 vaccine doses in patients with inflammatory bowel disease (IBD) who are treated with immunosuppressants, yet real-world data on the effectiveness and safety of additional vaccine doses is lacking. We sought to quantify the humoral immune response to an additional (third) dose of mRNA vaccines in adolescents and adult patients with IBD. Methods: We performed a direct-to-patient, internet-based cohort study of patients with IBD in the United States who have received any SARS-CoV-2 vaccine granted EUA. Participants completed baseline and follow-up surveys and had blood work obtained approximately 8 weeks following completion of the initial vaccination series and 6 weeks following administration of an additional (third) vaccine dose. We performed quantitative measurement of antireceptor binding domain (RBD) IgG antibodies specific to SARS-CoV-2 using the LabCorp Cov2Quant IgG™ assay. Results: A total of 659 participants were included [415 participants (63%) initially received BNT162b2, 243 participants (37%) initially received mRNA-1273, and 5 participants (1%) initially received Ad26.COV2.S]. Demographic, clinical, and treatment characteristics of the study population are provided in Table 1. Over 98% of those receiving an initial mRNA vaccine received the same type additional dose. Whereas 93% had detectable antibody after the initial vaccination series, 99.5% had detectable antibodies following an additional dose. Mean (SD) increase in antibody level was 61 ug/mL (103) in those receiving BNT162b2 and 78 ug/mL (143) for those receiving mRNA-1273 (Figure 1). Importantly, of 47 of patients without initial antibody response, 45 (96%) had detectable antibodies following an additional dose. Additional vaccination was generally well tolerated in this population, with 44%, 24%, 25%, and 6% reporting no, mild, moderate, and severe side effects respectively. Discussion: These findings demonstrate robust immunogenicity to additional doses of SARS-CoV-2 vaccine, even amongst patients with undetectable antibody following the initial series. Adverse event rates were low. These data can be used to inform vaccine decisions in patients with a broad array of immune-medicated conditions frequently managed by immunosuppression. (Table Presented) (Figure Presented)

14.
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)

15.
Gastroenterology ; 162(7):S-593-S-594, 2022.
Article in English | EMBASE | ID: covidwho-1967336

ABSTRACT

Background: The immune response of SARS-CoV-2 vaccines is uncertain in those with Inflammatory Bowel Disease (IBD) due to a diverse array of immune-modifying therapies that vary in the mechanism of immunosuppression. Aim: We aimed to quantify the serological response to SARS-CoV-2 vaccines in those with IBD and determine antibody levels across varying therapeutic options. Methods: Individuals with IBD who received a first and/or second dose of a COVID-19 vaccine (Pfizer-BioNTech, Moderna, and/or AstraZeneca) were assessed for serological response (1–8 weeks after first dose;1–8 weeks after second dose, 8–18 weeks after second dose, 18+ weeks after second dose) using the SARS-CoV-2 IgG II Quant assay to the receptor-binding domain of the SARS-CoV-2 spike protein. The cohort was stratified based on age, sex, vaccine received, IBD type, IBD therapeutic, and prior confirmed diagnosis of COVID-19. The primary outcome was seroconversion defined as IgG levels of ³50 AU/mL. Secondarily, we evaluated the geometric mean titer (GMT) with 95% confidence intervals (CI). Results: Table 1 describes the characteristics of individuals with IBD (n=466) with serological data following the first dose (n=247) and/or second dose (n=413) of a COVID-19 vaccine. After 1–8 weeks following first dose of the vaccine, 81.4% seroconverted, with the lowest first-dose conversion rates in patients taking anti- TNF monotherapy (80.3%), anti-TNF combination therapy (51.5%), and corticosteroids (50.0%) (Table 1). Overall, 98.4% of the cohort seroconverted within 1–8 weeks of the second dose. Over time, seropositive rates decreased with 95.8% seroconversion within 8– 18 weeks of the second dose and 90.5% after 18 weeks. Seroconversion after second dose was consistently high across all medication classes (range: 94.6%–100.0%), except for oral corticosteroids (62.5%). GMT levels significantly increased (p<0.0001) from first dose (1825 AU/mL [95% CI: 981, 2668 AU/mL]) to second dose at 1–8 week (9059 AU/mL [7698, 10420 AU/mL]) but fell significantly (p<0.0001) to 3649 AU/mL (95% CI: 2562, 4736 AU/ mL) 8–18 weeks from second dose and 2527 AU/mL (95% CI: 883, 4172 AU/mL) 18+ weeks after second dose (Table 1, Figure 1). GMT levels 1–8 weeks after second dose were higher in those with prior COVID-19 (16,770 AU/mL), but lower in those receiving anti- TNF combination therapy (4231 AU/mL) and oral corticosteroids (5996 AU/mL) (Table 1). Conclusion: Seroconversion rates following full-regimen vaccination are high in patients with inflammatory bowel disease across all medication classes except for anti-TNF combination therapy and oral corticosteroids. Antibody titres and seroconversion rates tend to decrease after eight weeks post-full vaccination, which is consistent across medication classes. (Table Presented) Table 1. Patient and vaccine characteristics, seroconversion rates, and geometric mean titres by prior PCR-confirmed COVID-19 status for each medication class. (Figure Presented) Figure 1. Log-transformed anti-SARS-CoV-2 spike antibody concentration per vaccine category. Black points represent GMTs while narrow black bars represent bounds of 95% CI associated with each GMT. Solid blue line represents threshold for positive seroconversion [ln (50 AU/mL)].

16.
Gastroenterology ; 162(7):S-364, 2022.
Article in English | EMBASE | ID: covidwho-1967299

ABSTRACT

Background: Diarrhea is present in up to 36.6% of patients with COVID-19. The mechanism of SARS-CoV-2-induced diarrhea remains unclear. We hypothesized that enterocyte-enteric neuron interactions were important in SARS-CoV-2-induced diarrhea. SARS-CoV-2 induces endoplasmic reticulum (ER) stress in enterocytes causing the release of Damage Associated Molecular Patterns (DAMPs). The DAMPs then stimulate the release of enteric neurotransmitters that disrupt gut electrolyte homeostasis. The influence of ER stress and enteric neuronderived vasoactive intestinal peptide (VIP) on the expression of Na+/H+ exchanger 3 (NHE3), an important transporter that mediates intestinal Na+/fluid absorption, was further examined. Methods: SARS-CoV-2 propagated in Vero-E6 cells was used to infect Caco-2, a human colon epithelial cell line that expresses SARS-CoV-2 entry receptor ACE2. The expression of ER stress markers, phospho-PERK, Xbp1s, and DAMP proteins, was examined by Western blotting. Primary mouse enteric neurons were treated with a conditioned medium of Caco- 2 cells that were infected with SARS-CoV-2 or treated with tunicamycin. VIP expression by cultured enteric neurons was assessed by RT-qPCR, Western blotting, and ELISA. Membrane expression of NHE3 was determined by surface biotinylation. Results: SARS-CoV-2 infection of Caco-2 cells led to increased expression of phospho-PERK and Xbp1s indicating increased ER stress. Infected Caco-2 cells secreted DAMP proteins, including HSP70 and calreticulin, as revealed by proteomic and Western analyses. The expression of VIP mRNA in enteric neurons was up-regulated after treatment with a conditioned medium of SARS-CoV-2- infected Caco-2 cells (Mock, 1 ± 0.0885;and SARS-CoV-2, 1.351 ± 0.020, P=.005). CD91, a receptor for HSP70 and calreticulin, is abundantly expressed in cultured mouse and human enteric neurons and was up-regulated by a conditioned medium of SARS-CoV-2-infected Caco-2 cells. Tunicamycin, an inducer of ER stress, also induced the secretion of HSP70 and calreticulin, mimicking SARS-CoV-2 infection. Moreover, co-culture of enteric neurons with tunicamycin-treated Caco-2 cells stimulated VIP production as determined by ELISA. Co-treatment of Caco-2 cells with tunicamycin (apical) and VIP (basolateral) induced a synergistic decrease in the membrane expression of NHE3. Conclusions: Our findings demonstrate that SARS-CoV-2 infection of enterocytes leads to ER stress and the release of DAMPs that up-regulate the expression and release of VIP by enteric neurons. The presence of ER stress together with the secreted VIP, in turn, inhibits fluid absorption through the downregulation of brush-border membrane expression of NHE3 in the enterocytes. These data highlight epithelial-neuronal crosstalk in COVID-19 related diarrhea. (Figure Presented)

17.
Gastroenterology ; 162(7):S-287, 2022.
Article in English | EMBASE | ID: covidwho-1967277

ABSTRACT

Introduction: The immunogenicity and safety following standard two-dose SARS-CoV-2 vaccination in patients with immune-mediated inflammatory diseases (IMIDs) are not well characterised, and data on third dose vaccination in this patient group are currently lacking. Methods & Aims: This prospective, observational cohort study included adult patients on immunosuppressive therapy for Crohn's disease (CD), ulcerative colitis (UC), rheumatoid arthritis (RA), spondyloarthritis (SpA), psoriatic arthritis (PsA), and healthy controls receiving standard two-dose SARS CoV-2 vaccination. Patients with a weak serologic response (<100 AU/ml) were allotted a third vaccine dose. Serum samples were collected prior to, and after vaccination for analyses of antibodies to the receptor-binding domain (RBD) of the SARSCoV- 2 spike protein. The aim of the study was to evaluate the immunogenicity and safety following standard and three dose SARS-CoV-2 vaccination in IMID patients on immunosuppressive therapies. Results: a total of 1641 patients (280 CD, 195 UC, 566 RA, 305 SpA, 295 PsA, median age 52 [IQR 40-63], 899 [55%] women), and 1114 healthy controls (median age 43 [IQR 32-55], 854 [77%] women), were included in the study. After standard SARS-CoV-2 two dose vaccination, 1504 (91%) patients compared to 1096 (98%) healthy controls were responders, p<0,001. Anti-RBD levels were lower in patients (median 619 AU/ml [IQR 192-4191]) than controls (median 3355 AU/ml [IQR 896–7849]), p<0,001. Response was shown in ≤90% of patients receiving methotrexate, tumor necrosis factor inhibitor (TNFi) monotherapy, ustekinumab, tozilizumab and vedolizumab, in 80–90% of patients receiving TNFi combination therapy and secukinumab and in £ 80% for JAK inhibitors (78%), and abatacept (53%) (fig.1). Lower age (OR 0.96 [95% CI 0.95–0.98]) and receiving the mRNA-1273 vaccine (OR 5.4 [95% CI 2.4–11.9]) were predictors of response. Of 153 patients with a weak response receiving a third vaccine dose, 129 (84%) became responders. After standard two dose vaccination, adverse events (AE) were reported in 50% of patients and in 78% of controls, with a comparable safety profile. Following the third dose, 44% of patients reported AEs, without new safety issues emerging. No serious AEs were reported. Conclusion: Response rate as well as anti-RBD levels were lower in IMID patients than healthy controls following standard vaccination. Third dose vaccination in serologically weak responders was safe and resulted in a response in most patients. Our data facilitate identification of patient groups at risk of an attenuated vaccine response eligible for post-vaccination serological monitoring. The data also support a third vaccine dose following standard SARS-CoV-2 vaccination to weak-responding IMID-patients. (Figure Presented) Fig.1 Anti-SARS-CoV-2 IgG antibodies following standard two dose SARS-CoV-2 vaccination according to medication group, compared to healthy controls. Violin plot showing the probability density of the data at different values, smoothed by a kernel density estimator. Each data point is a participant, and the solid orange line show the group median. The last row (CTRL vs) shows p-values for a comparison (Mann-Whitney U test) of anti-SARS-COV 2 antibodies between medication groups and healthy controls. ACE=Angiotensin converting enzyme, FL=full length, CTRL=Controls, TNF=Tumor necrosis factor inhibitor, TNF+= Tumor necrosis factor inhibitor combination therapy, MTX=methotrexate, VDZ=vedolizumab, JAK=Janus kinase inhibitor, TCZ=tocilizumab, UST=ustekinumab, ABA=abatacept, SCK=secukinumab.

18.
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)

19.
Gastroenterology ; 162(7):S-160-S-161, 2022.
Article in English | EMBASE | ID: covidwho-1967251

ABSTRACT

Background: The immune response to a two-dose regimen of SARS-CoV-2 vaccination in those with Inflammatory Bowel Disease (IBD) has been consistently high in emerging research. Serological responses following a third dose have yet to be established. Aim: We aimed to quantify the serological response to a third dose of SARS-CoV-2 vaccines in those with IBD and compare to responses after a two-dose regimen. Methods: Individuals with IBD who have received at least two doses of a COVID-19 vaccine were assessed for serological response using the SARS-CoV-2 IgG II Quant assay to the receptor-binding domain of the SARSCoV- 2 spike protein at least eight weeks after second dose and then after third dose. The primary outcome was seroconversion defined as IgG levels of ≥50 AU/mL. Secondarily, we evaluated the geometric mean titer (GMT) with 95% confidence intervals (CI). Outcomes were stratified by prior COVID-19 history. A Wilcoxon rank sum test was used to compare antibody titres following 3rd dose vaccination and titres following 2nd dose vaccination. For patients with both post-2nd and post-3rd vaccination serology, the difference in antibody titres between doses was determined and the mean difference was tested using one-sample Student's t-tests. Results: Table 1 describes the characteristics of individuals with IBD (n = 271) with serological data following the corresponding dose for those with 2nd dose vaccination (n = 175) compared to those with a 3rd dose of vaccine (n = 96). Seroconversion following 3rd dose vaccination occurred for all individuals (100.0%), compared to a 94.4% seroconversion rate at least eight weeks following 2nd dose vaccination (range: 8 to 35 weeks post-2nd dose). GMT for the post-3rd dose cohort (16424 AU/mL [13437, 19411 AU/mL]) was significantly higher (p<0.0001) than the post-2nd dose cohort (3261 AU/mL [2356, 4165 AU/mL] (Table 1, Figure 1b). Individual titres as a function of time following 2nd dose vaccination are seen in Figure 1a for both 3rd dose and 2nd dose cohorts. For individuals with serology following both 2nd dose and 3rd dose vaccination (n = 82), seroconversion rates increased from 97.6% to 100.0% after the 3rd dose. GMT following post-3rd dose vaccination also increased with a mean difference in antibody titres between post-3rd dose and post-2nd dose vaccination of 11384 AU/mL (8541, 14228 AU/mL, p < 0.0001). This difference was significant for both individuals with prior COVID-19 history (11682 AU/mL [95% CI: 8618, 14746 AU/mL, p<0.0001]) and individuals without (8194 AU/mL [95% CI: 988, 15400 AU/mL]). Conclusion: Seroconversion rates and antibody response following third dose vaccination are substantially increased as compared to second dose in patients with IBD. Third dose vaccination can counter the decrease in antibody concentration over time following a two-dose regimen. (Table Presented) Table 1. Patient characteristics, vaccine type, seroconversion rates, and geometric mean titres by prior COVID-19 status for post-3rd dose and post-2nd dose cohorts

20.
Gastroenterology ; 162(7):S-160, 2022.
Article in English | EMBASE | ID: covidwho-1967250

ABSTRACT

Background: Vaccine-induced protection against SARS-CoV-2 infection is predominantly mediated by humoral immunity;protection against disease progression is primarily determined by cellular immunity. Patients with inflammatory bowel disease (IBD) have high rates of post-vaccination anti-Spike IgG [IgG(S)] seroconversion, but postvaccination immune responses relative to non-IBD controls have not been well described. We aimed to assess post-vaccination humoral (antibody) and cellular (T-cell) responses in IBD relative to healthcare worker (HCW) controls. Methods: We evaluated IBD patients enrolled in a US registry referred from 26 centers at 2, 8, and 16 weeks after completing 2 doses of SARSCoV- 2 mRNA vaccination and compared results to non-IBD non-immunosuppressed HCW participating in a parallel study. We analyzed plasma antibodies to the receptor binding domain of the viral spike protein using the SARS-CoV-2 IgG-II assay (Abbott Labs, Abbott Park, IL);IgG(S) > 50 AU/mL was defined as positive. Those with prior COVID were excluded. We also performed T-cell clonal analysis by T-cell receptor (TCR) immunosequencing at 8 weeks (Adaptive Biotechnologies, Seattle, WA). The breadth (number of unique sequences to a given protein) and depth (relative abundance of all the unique sequences to a given protein) of the T-cell clonal response were quantified using reference datasets. Analyses were adjusted for age, sex and vaccine type. Results: Overall, 1805 subjects were included (IBD n=1074 (65% Crohn's disease, 35% ulcerative colitis);HCW n=731). Age and sex were similar between both cohorts;Hispanic ethnicity and Asian race were less common among IBD than HCW (Table). Vaccine type included BNT162b2 (Pfizer) (75% of IBD, 98% of HCW) and the remainder mRNA-1274 (Moderna). IBD treatments included anti- TNF (46%), other biologics (33%), other immune suppressing therapy (9%), and no immune suppression (12%). Postvaccination antibody levels were lower among IBD than HCW both before and after adjusting for vaccine type (p<0.0001 each timepoint;Figure). After further restricting the IBD cohort to those on no immune-suppressive therapies, antibodies remained lower in IBD vs HCW at 2w (p=0.008) and 8w (p<0.0001), but not 16w (p=0.07). Among 321 subjects with available whole cell samples at 8 weeks (IBD n=163, HCW =158), Spikespecific TCR responses were similar between IBD and HCW for both clonal breadth and depth in both unadjusted and adjusted analyses;sub-analyses of those on biologics yielded similar results. Conclusion: Patients with IBD have dampened humoral responses, but similar cellular responses, after SARS-CoV-2 mRNA vaccination relative to HCW. These findings suggest a potentially greater risk of infection, but not of disease progression, among those with IBD, and should be considered to help guide booster dosing strategies for the IBD population. (Figure Presented) (Figure Presented) Figure: Post-vaccination immune responses: (A) Antibody responses are lower in IBD relative to non-IBD healthcare workers at 2, 8, and 16 weeks (p<0.0001 at each timepoint). In contrast, post-vaccination Spike-specific T-cell receptor clonal breadth (B1) and clonal depth (B2) at 8 weeks are similar in IBD compared to healthcare workers.

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