In a cohort of BNT162b2 (Pfizer–BioNTech) mRNA vaccine recipients (n = 1,090), we observed that spike-specific IgG antibody levels and ACE2 antibody binding inhibition responses elicited by a single vaccine dose in individuals with prior SARS-CoV-2 infection (n = 35) were similar to those seen after two doses of vaccine in individuals without prior infection (n = 228). Post-vaccine symptoms were more prominent for those with prior infection after the first dose, but symptomology was similar between groups after the second dose.

Background. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused over one million deaths worldwide, thus there is an urgent need to develop preventive and therapeutic strategies. The anti-tuberculosis vaccine Bacillus Calmette-Guérin (BCG) demonstrates nonspecific protective innate immune-boosting effects. Here, we determined if history of BCG vaccination was associated with decreased SARS-CoV-2 infection and seroconversion in a longitudinal, retrospective observational study of a diverse cohort of healthcare workers (HCWs). Methods. We assessed SARS-CoV-2 seroprevalence and collected medical questionnaires, including BCG vaccination status and pre-existing demographic and clinical characteristics, from an observational cohort of HCWs in a multi-site Los Angeles healthcare organization. We used multivariate analysis to estimate if history of BCG vaccination was associated with decreased rates of SARS-CoV-2 infection and seroconversion. Results. Of the 6,201 HCWs, 29.6% reported a history of BCG vaccination whereas 68.9% did not receive BCG vaccination. Seroprevalence of anti-SARS-CoV-2 IgG as well as incidence of self-reported clinical symptoms associated with COVID-19 were significantly decreased among HCWs with a history of BCG vaccination compared to those without BCG vaccination. After adjusting for age and sex, we found that history of BCG vaccination, but not meningococcal, pneumococcal or influenza vaccination, was associated with decreased SARS-CoV-2 IgG seroconversion. Conclusions. History of BCG vaccination was associated with decreased seroprevalence of anti-SARS-CoV-2 IgG and reduced reported COVID-19-related clinical symptoms in this cohort of HCWs. Therefore, large randomized prospective clinical trials of BCG vaccination are urgently needed to confirm if BCG vaccination can induced a protective effect against SARS-CoV2 infection.

No abstract

Sample preparation for protein quantification by mass spectrometry requires multiple processing steps including denaturation, reduction, alkylation, protease digestion, and peptide cleanup. Scaling these procedures for the analysis of numerous complex biological samples can be tedious and time-consuming, as there are many liquid transfer steps and timed reactions where technical variations can be introduced and propagated. We established an automated sample preparation workflow with a total processing time for 96 samples of 5 h, including a 2 h incubation with trypsin. Peptide cleanup is accomplished by online diversion during the LC/MS/MS analysis. In a selected reaction monitoring (SRM) assay targeting 6 plasma biomarkers and spiked β-galactosidase, mean intraday and interday cyclic voltammograms (CVs) for 5 serum and 5 plasma samples over 5 days were <20%. In a highly multiplexed SRM assay targeting more than 70 proteins, 90% of the transitions from 6 plasma samples repeated on 3 separate days had total CVs below 20%. Similar results were obtained when the workflow was transferred to a second site: 93% of peptides had CVs below 20%. An automated trypsin digestion workflow yields uniformly processed samples in less than 5 h. Reproducible quantification of peptides was observed across replicates, days, instruments, and laboratory sites, demonstrating the broad applicability of this approach.

C urrently, 3 vaccines have been granted Emergency Use Authorization for coronavirus disease 2019 prevention in the United States. These include the messenger RNA (mRNA) platform vaccines (mRNA-1273; Moderna/National Institutes of Health) and BNT162b2 (Pfizer-BioNTech) and an adenovirus vector vaccine (Ad26.CoV2.S; Johnson & Johnson), which were 94%, 95%, and 67% effective against COVID-19 infection in their phase III registry trials against the endemic variants at the time, respectively. 1-3 All 3 vaccines target the viral spike (S) protein that facilitates severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry into host cells via its receptor binding domain, which interacts with angiotensin-converting enzyme 2. 4 Although the mRNA platform vaccines are 2-dose vaccines administered 3-4 weeks apart, the Ad26.CoV2.S is administered as a single dose. Another adenovirus vector vaccine (ChAdOx1; Astrazeneca), not yet authorized in the United States, is intended as a 2-dose regimen with an interval of 8-12 weeks.Patients with inflammatory bowel disease (IBD) on corticosteroids, immunomodulators, and advanced therapies may have normal to slightly decreased humoral responses to the SARS-CoV-2 mRNA vaccine platforms. 1 In addition, patients receiving infliximab and/or thiopurines have significantly lower rates of seroconversion than those on vedolizumab monotherapy after a single dose of either BNT162b2 or ChAdOx1. 2 A study of solid organ transplant recipients showed decreased humoral responses to Ad26.CoV2.S vaccine relative to both mRNA platform vaccines, although it is unknown whether these findings are generalizable to other immune compromised populations. 5 Q5 We aimed to assess for differences in serologic responses among patients with IBD who received Ad26.CoV2.S relative to those receiving mRNA-1273 or BNT162b2. Among 353 vaccine recipients with IBD participating in a prospective SARS-CoV-2 vaccine registry without prior COVID-19 infection and who had completed a full vaccine regimen, 148 (42%), 193 (55%), and 12 (3%) received mRNA-1273, BNT162b2, and Ad26.CoV2.S, respectively. Demographic and disease characteristics were similar across vaccine groups (mean age, 51 years, 62% were female) (Supplementary Table 1). Approximately 290 (83.1%) participants were on immune-modifying therapies (IMTs), as defined by receipt of advanced therapies (biologics or JAK inhibitors, 80.2%), immunomodulators (16.6%), and/or systemic corticosteroids (6.6%) at the time of initial vaccination. At least 2 weeks after completion of the vaccine regimen, positive antibody levels were detected in 121 (100%), 142 (99%), and 9 (90%) patients receiving mRNA-1273, BNT162b2, and Ad26.CoV2.S, respectively (Figure 1A). Quantitative log 10 (anti-Spike IgG

ObjectiveWe sought to determine the extent of SARS-CoV-2 seroprevalence and the factors associated with seroprevalence across a diverse cohort of healthcare workers.DesignObservational cohort study of healthcare workers, including SARS-CoV-2 serology testing and participant questionnaires.SettingsA multisite healthcare delivery system located in Los Angeles County.ParticipantsA diverse and unselected population of adults (n=6062) employed in a multisite healthcare delivery system located in Los Angeles County, including individuals with direct patient contact and others with non-patient-oriented work functions.Main outcomesUsing Bayesian and multivariate analyses, we estimated seroprevalence and factors associated with seropositivity and antibody levels, including pre-existing demographic and clinical characteristics; potential COVID-19 illness-related exposures; and symptoms consistent with COVID-19 infection.ResultsWe observed a seroprevalence rate of 4.1%, with anosmia as the most prominently associated self-reported symptom (OR 11.04, p<0.001) in addition to fever (OR 2.02, p=0.002) and myalgias (OR 1.65, p=0.035). After adjusting for potential confounders, seroprevalence was also associated with Hispanic ethnicity (OR 1.98, p=0.001) and African-American race (OR 2.02, p=0.027) as well as contact with a COVID-19-diagnosed individual in the household (OR 5.73, p<0.001) or clinical work setting (OR 1.76, p=0.002). Importantly, African-American race and Hispanic ethnicity were associated with antibody positivity even after adjusting for personal COVID-19 diagnosis status, suggesting the contribution of unmeasured structural or societal factors.Conclusion and relevanceThe demographic factors associated with SARS-CoV-2 seroprevalence among our healthcare workers underscore the importance of exposure sources beyond the workplace. The size and diversity of our study population, combined with robust survey and modelling techniques, provide a vibrant picture of the demographic factors, exposures and symptoms that can identify individuals with susceptibility as well as potential to mount an immune response to COVID-19.

The double dose regimen for mRNA vaccines against SARS-CoV-2 presents both a hope and a challenge for global efforts to curb the COVID-19 pandemic. With supply chain logistics impacting the rollout of population-scale vaccination programs, increasing attention has turned to the potential efficacy of single versus double dose vaccine administration for select individuals. To this end, we examined response to Pfizer-BioNTech mRNA vaccine in a large cohort of healthcare workers including those with versus without prior COVID-19 infection. For all participants, we quantified circulating levels of SARS-CoV-2 anti-spike (S) protein IgG at baseline prior to vaccine, after vaccine dose 1, and after vaccine dose 2. We observed that the anti-S IgG antibody response following a single vaccine dose in persons who had recovered from confirmed prior COVID-19 infection was similar to the antibody response following two doses of vaccine in persons without prior infection (P>0.57). Patterns were similar for the post-vaccine symptoms experienced by infection recovered persons following their first dose compared to the symptoms experienced by infection naive persons following their second dose (P=0.66). These results support the premise that a single dose of mRNA vaccine could provoke in COVID-19 recovered individuals a level of immunity that is comparable to that seen in infection naive persons following a double dose regimen. Additional studies are needed to validate our findings, which could allow for public health programs to expand the reach of population wide vaccination efforts.

This variation in practice indicates an opportunity exists to establish an evidence-based approach to QC that can be generalized across institutions.