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2.
Gastroenterology ; 162(7):S-1006, 2022.
Article in English | EMBASE | ID: covidwho-1967392

ABSTRACT

BACKGROUND Little is known about the impact of immunosuppressants on COVID-19 vaccination in patients with immune-mediated inflammatory diseases (IMID). Although humoral response may be attenuated in patients using immunomodulators (IMM) and TNFinhibitors (anti-TNF), data regarding cellular response are scarce and conflicting. This study was aimed to identify immune response to COVID-19 vaccination in IMID patients. METHODS A prospective observational multicentre cohort study was conducted to examine the immunogenicity of mRNA vaccines to SARS-CoV-2 in adult IMID patients using immunosuppressive therapy (anti-TNF, IMM, anti-TNF+IMM, anti-IL12/23, anti-IL-17, anti-IL-23) or no therapy as compared to healthy controls (HC). Patient details and vaccination history were recorded. Blood samples were drawn at 3 time points: before, 3-4 weeks after first and 2 weeks after second vaccination. Humoral immune response to S and RBD proteins were assessed by ELISA. Neutralization was tested against 4 variants of SARS-CoV-2 by surrogate neutralization ELISA. Cellular immune responses were determined based on analysis of 9 secreted cytokines and cytotoxic molecules after stimulation of PBMC with S peptide pools. Response to N protein was used to assess SARS-CoV-2 exposure. RESULTS A total of 159 subjects (133 IMID patients and 26 HC) were included in this study (median age 42 years [IQR 30-53], 52% male). Of 133 IMID patients, 87 had inflammatory bowel disease, 23 psoriatic arthritis, 18 psoriasis, 11 ankylosing spondylarthritis and 4 rheumatoid arthritis. Of these, 44 used anti-TNF, 9 IMM, 18 anti-TNF+IMM, 33 anti-IL-12/23, 9 anti-IL-17, 10 anti-IL-23 therapy and 10 no therapy. All subjects received 2 doses of mRNA vaccines (2x Pfizer, 2x Moderna or mixed) between December 2020 and September 2021. The vast majority of subjects had minimal binding antibody and T cell responses to N, indicating they were COVID-19 naïve. After dose 1, anti-TNF group had lower IL-2 vs untreated IMID (p<0.01), and the anti-IL-23 group had lower IFN-g vs HC (p<0.01), though there was wide variation in responses within groups. Following dose 2, median responses between groups were mostly similar, but antibody responses were significantly lower in patients on anti-TNF as compared to HC in subjects that received two doses of Pfizer (p=0.01). Pooled data for all subjects combined show a higher response to Moderna over Pfizer in ELISA, neutralization and T cell readouts, and a lower response for those over 60 years of age after dose 2. Longer follow-up is in process to monitor the durability of these responses over time and after third dose. CONCLUSION Immune responses after 2 doses of mRNA vaccines in immunocompromised IMID patients largely reach the level of that of HC albeit antibody responses in the anti-TNF group are weaker and with wide variability between subjects within some groups

3.
Topics in Antiviral Medicine ; 30(1 SUPPL):348, 2022.
Article in English | EMBASE | ID: covidwho-1881001

ABSTRACT

Background: In attempts to rapidly immunize a greater proportion of the Ontario population against COVID, public health officials recommended extending the interval between vaccine doses and allowed "mixing of vaccine types". The impact of these decisions on the antibody response to the vaccine, particularly in the community dwelling elderly population is unknown. Methods: The STOPCoV study is designed to compare the IgG antibody response to spike protein and receptor binding domain (RBD) after COVID vaccination in those aged ≥ 70 years relative to a cohort aged 30-50 years. This prospective decentralized observational study is conducted remotely on a digital platform (www.stopcov.ca). Participants signed an e-consent, completed questionnaires and will submit dried blood spot (DBS) specimens 6-8 times over 48 weeks after the second vaccine dose. DBS samples were analyzed for IgG antibodies to spike and RBD by an in-house ELISA. We report here the ratio-normalized levels of anti-spike and anti-RBD IgG antibodies prior to and at 2 weeks after the second vaccine with comparisons between age groups. Linear regression models were used to determine the effect of age on the ratio normalized RBD antibody levels 2 weeks post second dose of vaccine after adjusting for potential confounders determined a priori. Results: 1286 persons enrolled between May 17 and July 31, 2021. 1194 participants (853 > 70 years;341 aged 30-50) completed at least one study related task. 761 (64.1%) are female. Most received an mRNA vaccine, with 863 (74%) receiving the same vaccine brand, and 196 (17%) receiving mixed brands over 2 doses. Two weeks after the second vaccine dose, the median interquartile rangeanti-spike antibody level was 0.76 [0.45, 1.16] for those ≥70 compared to 1.3 [0.98, 1.56] for those 30-50 (p<0.001). The median anti-RBD antibody levels were 0.28 [0.15, 0.53] and 0.66 [0.41, 1.08] (p<0.001) for the older and younger cohorts respectively. After adjusting for gender, cardiovascular disease, cancer, diabetes, transplant or immune suppression, body mass index, vaccine brand, and time between doses, participants ≥70 had lower levels of anti-RBD antibodies at 2 weeks after 2nd dose (β=-0.14, 95% confidence interval-0.19,-0.08, p<0.0001). Conclusion: High antibody levels against COVID-19 are attainable after 2 doses of mRNA vaccines. Levels were higher with Moderna than Pfizer. Delay of the second dose to 4 months or mixing of brands had minimal impact on the antibody level but levels are lower in the elderly.

6.
Embase; 2022.
Preprint in English | EMBASE | ID: ppcovidwho-333915

ABSTRACT

Background Limited information is available on the impact of immunosuppressants on COVID-19 vaccination in patients with immune-mediated inflammatory diseases (IMID). Methods This observational cohort study examined the immunogenicity of SARS-CoV-2 mRNA vaccines in adult patients with inflammatory bowel disease, rheumatoid arthritis, ankylosing spondylitis, or psoriatic disease, with or without maintenance immunosuppressive therapies. Antibody and T cell responses to SARS-COV-2, including neutralization against SARS-CoV-2 variants were determined before and after 1 and 2 vaccine doses. Results We prospectively followed 150 subjects, 26 healthy controls, 9 IMID patients on no treatment, 44 on anti-TNF, 16 on anti-TNF with methotrexate/azathioprine (MTX/AZA), 10 on anti-IL-23, 28 on anti-IL-12/23, 9 on anti-IL-17, and 8 on MTX/AZA. Antibody and T cell responses to SARS-CoV-2 were detected in all participants, increasing from dose 1 to dose 2 and declining 3 months later, with greater attrition in IMID patients compared to healthy controls. Antibody levels and neutralization efficacy against variants of concern were substantially lower in anti-TNF treated patients than in healthy controls and were undetectable against Omicron by 3 months after dose 2. Conclusions Our findings support the need for a third dose of mRNA vaccine and for continued monitoring of immunity in these patient groups.

7.
Embase; 2021.
Preprint in English | EMBASE | ID: ppcovidwho-330471

ABSTRACT

Although SARS-CoV-2 infects the upper respiratory tract, we know little about the amount, type, and kinetics of antibodies (Ab) generated at this site in response to intramuscular COVID-19 vaccination, and whether these Ab protect against subsequent “breakthrough” infections. We collected longitudinal serum and saliva samples from participants receiving two doses of mRNA COVID-19 vaccines over a 6-month period and measured the relative level of anti-Spike and anti-Receptor Binding Domain (RBD) Ab. We detected anti-Spike/RBD IgG and IgA and associated secretory component in the saliva of most participants receiving 1 dose of mRNA vaccine. Administration of a second dose of mRNA boosted the IgG but not the IgA response, with only 30% of participants remaining positive for IgA at this timepoint. At 6 months post-dose 2, these participants exhibited greatly diminished anti-Spike/RBD IgG and IgA levels concomitant with a reduction in neutralizing activity in the saliva, although the level of secretory component associated anti-Spike was less susceptible to decay. Examining two prospective cohorts of subjects that were monitored for infections post-vaccination, we found that participants who were subsequently infected with SARS-CoV-2 had lower levels of vaccine-induced serum anti-Spike/RBD IgA at 2-4 weeks post-dose 2 compared to participants who did not experience an infection, whereas IgG levels were comparable between groups. These data emphasize the importance of developing COVID-19 vaccines that elicit a durable IgA response.

8.
Kidney international reports ; 7(2):S426-S427, 2022.
Article in English | EuropePMC | ID: covidwho-1695121
9.
Kidney International Reports ; 7(2):S426-S427, 2022.
Article in English | PMC | ID: covidwho-1693509
11.
Journal of the American Society of Nephrology ; 32:95, 2021.
Article in English | EMBASE | ID: covidwho-1490284

ABSTRACT

Background: Hemodialysis (HD) patients have high mortality from COVID-19 and immunity following vaccination remains uncertain. This study evaluated SARS-CoV-2 antibody response in HD patients following BNT162b2 COVID-19 vaccination compared to health care workers (HCW) and convalescent serum. Methods: This single centre observational cohort study enrolled 142 HD patients and 35 HCW receiving the BNT162b2 vaccine. SARS-CoV-2 IgG antibodies to the spike protein (anti-spike), receptor binding domain (anti-RBD), and nucleocapsid protein (anti-NP) were measured in 66 HD patients receiving one vaccine dose, 76 HD patients receiving two vaccine doses, and 35 HCW receiving two vaccine doses. Results: In HD patients receiving a single BNT162b2 dose, seroconversion occurred in 53/66 (80%) for anti-spike and 35/66 (55%) for anti-RBD by 28 days post dose, but only 15/66 (23%) and 4/66 (6%), respectively attained a robust response defined as reaching the median level of anti-spike and anti-RBD in convalescent serum. In patients receiving two doses of BNT162b2 vaccine, seroconversion occurred in 69/72 (96%) for anti-spike and 63/72 (88%) for anti-RBD by 2 weeks following the second dose while 52/72 (72%) and 43/72 (60%) reached median convalescent serum levels of anti-spike and anti-RBD. In HCW, 35/35 (100%) exceeded median levels of anti-spike and anti-RBD in convalescent serum 2-4 weeks post second dose. Conclusions: This study found poor immunogenicity 28 days following a single dose of BNT162b2 vaccine in HD patients, supporting adherence to recommended vaccination schedules, and avoiding delay of the second dose in this population.

12.
Transfusion ; 61(SUPPL 3):196A-197A, 2021.
Article in English | EMBASE | ID: covidwho-1467638

ABSTRACT

Background/Case Studies: Multiple assays to detect SARS-COV-2 antibodies are available but no gold standard exists. Due to many factors including waning antibodies and differences in test designs, discordance between SARS-CoV-2 serology assays is common. Given these limitations we used multiple assays and methodological approaches to estimate SARS-COV-2 seroprevalence during the first COVID-19 wave in Canada. Study Design/Methods: This serial cross-sectional study was conducted using residual plasma from healthy blood donors between April-September 2020. Qualitative (Table Presented) assessment of SARS-CoV-2 IgG antibodies was based on four assays: Abbott Architect SARS-Cov-2 IgG assay (target nucleocapsid) (Abbott-NP) and three in-house IgG ELISA assays (target spike glycoprotein (Spike), spike receptor binding domain (RBD), and nucleocapsid (NP)) based on thresholds set by the manufacture or 3-standarddeviations from the negative mean. We compared seroprevalence rates by multiple composite reference standards (CRS) and by a series of Bayesian Latent Class Models (BLCM) (using uninformative, weakly and informative priors). Using the BLCM we estimated assay characteristics, bimonthly to evaluate changes over time. Results/Findings: In total, 8999 blood samples were tested. The Abbott-NP assay consistently estimated seroprevalence to be lower than the ELISA-based assays. A priori, choosing a combination of 2 assays resulted in a range of seroprevalence estimates that ranged from 0.2% to 0.5% in April to 0.4% to 1.5% in September. From 16 possible diagnostic phenotypes, 13 were observed, only 33 samples (0.4%) were positive by all four assays. BLCM with non-informative priors provided the best model fit and predicted seroprevalence increased from 0.7% (95% CrI;0.6, 0.8%) in April/May to 1.0% (0.8, 1.1%) in June/ July to 1.5% (1.3, 1.8) in August/September. Assay characteristics varied considerably over time. Overall RBD had the highest sensitivity 82.2% (69.3, 92.9%) with a specificity of 99.6% (99.4, 99.7%). In contrast the sensitivity of the Abbott-NP assay was the lowest and waned from 63.2% (41.4, 83.1%) in April/May to 33.9% (19.7, 53.1%) by August/September. Conclusions: Regardless of the analytical method we found at the end of the first COVID-19 wave, SARSCoV- 2 seroprevalence among a healthy population of blood donors was low (<2%). While the sensitivity of all assays waned, the rates did vary. We found significant limitations to using a single assay to estimate SARSCoV- 2 seroprevalence in a low prevalence setting, such as healthy Canadian blood donors during the first wave of the COVID-19 pandemic.

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