Analysis of immunization time, amplitude, and adverse events of seven different vaccines against SARS-CoV-2 across four different countries. (preprint)

Background: Scarce information exists in relation to the comparison of seroconversion and adverse events following immunization (AEFI) with different SARS-CoV-2 vaccines. Our aim was to correlate the magnitude of the antibody response to vaccination with previous clinical conditions and AEFI. Methods: A multicentric comparative study where SARS-CoV-2 spike 1-2 IgG antibodies IgG titers were measured at baseline, 21-28 days after the first and second dose (when applicable) of the following vaccines: BNT162b2 mRNA, mRNA-1273, Gam-COVID-Vac, Coronavac, ChAdOx1-S, Ad5-nCoV and Ad26.COV2. Mixed model and Poisson generalized linear models were performed. Results: We recruited 1867 subjects [52 (SD 16.8) years old, 52% men]. All vaccines enhanced anti-S1 and anti-S2 IgG antibodies over time (p<0.01). The highest increase after the first and second dose was observed in mRNA-1273 (p<0.001). There was an effect of previous SARS-CoV-2 infection; and an interaction of age with SARS-CoV-2, Gam-COVID-Vac and ChAdOx1-S (p<0.01). There was a negative correlation of Severe or Systemic AEFI (AEs) of naive SARS-CoV-2 subjects with age and sex (p<0.001); a positive interaction between the delta of antibodies with Gam-COVID-Vac (p=0.002). Coronavac, Gam-COVID-Vac and ChAdOx1-S had less AEs compared to BNT162b (p<0.01). mRNA-1273 had a higher number of AEFIs. The delta of the antibodies showed an association with AEFIs in previously infected individuals (p<0.001). Conclusions: The magnitude of seroconversion is predicted by age, vaccine type and SARS-CoV-2 exposure. AEs are correlated with age, sex, and vaccine type. The delta of the antibody response is positively correlated with AEs in patients previously exposed to SARS-CoV-2.

mRNA COVID-19 vaccine booster fosters B and T cell responses in immunocompromised patients (preprint)

SARS-CoV-2 vaccination has proven effective in inducing an immune response in healthy individuals and is progressively allowing to overcome the pandemic. Recent evidence has shown that response to vaccination in some vulnerable patients may be diminished, and it has been proposed a booster dose. We tested the kinetic of development of serum antibodies to the SARS-CoV-2 Spike protein, their neutralizing capacity, the CD4 and CD8 IFN-γ T cell response in 328 subjects, including 131 immunocompromised individuals (cancer, rheumatologic, and hemodialysis patients), 160 healthcare workers (HCW) and 37 subjects older than 75 yo, after vaccination with two or three doses of mRNA vaccines. We stratified the patients according to the type of treatment. We found that immunocompromised patients, depending on the type of treatment, poorly respond to SARS-CoV-2 mRNA vaccines. However, an additional booster dose of vaccine induced a good immune response in almost all of the patients except those receiving anti-CD20 antibody. Similarly to HCW, previously infected and vaccinated immunocompromised individuals demonstrate a stronger SARS-CoV-2 specific immune response than those who are vaccinated without prior infection. Summary blurb Immunocompromised patients poorly respond to two doses of SARS-CoV-2 mRNA vaccines. However, an additional booster dose elicits a strong humoral and cellular immune response in these subjects.

New susceptibility loci for severe COVID-19 by detailed GWAS analysis in European populations (preprint)

Due to the highly variable clinical phenotype of Coronavirus disease 2019 (COVID-19), deepening the host genetic contribution to severe COVID-19 may further improve our understanding about underlying disease mechanisms. Here, we describe an extended GWAS meta-analysis of 3,260 COVID-19 patients with respiratory failure and 12,483 population controls from Italy, Spain, Norway and Germany, as well as hypothesis-driven targeted analysis of the human leukocyte antigen (HLA) region and chromosome Y haplotypes. We include detailed stratified analyses based on age, sex and disease severity. In addition to already established risk loci, our data identify and replicate two genome-wide significant loci at 17q21.31 and 19q13.33 associated with severe COVID-19 with respiratory failure. These associations implicate a highly pleiotropic ~0.9-Mb 17q21.31 inversion polymorphism, which affects lung function and immune and blood cell counts, and the NAPSA gene, involved in lung surfactant protein production, in COVID-19 pathogenesis.

The antibody response to SARS-CoV-2 increases over 5 months in patients with anosmia/dysgeusia (preprint)

The factors involved in the persistence of antibodies to SARS-CoV-2 are unknown. We evaluated the antibody response to SARS-CoV-2 in personnel from 10 healthcare facilities and its association with individuals' characteristics and COVID-19 symptoms in an observational study. We enrolled 4735 subjects (corresponding to 80% of all personnel) over a period of 5 months when the spreading of the virus was drastically reduced. For each participant, we determined the rate of antibody increase or decrease over time in relation to 93 features analyzed in univariate and multivariate analyses through a machine learning approach. In individuals positive for IgG (>= 12 AU/mL) at the beginning of the study, we found an increase [p= 0.0002] in antibody response in symptomatic subjects, particularly with anosmia/dysgeusia (OR 2.75, 95% CI 1.753 - 4.301), in a multivariate logistic regression analysis. This may be linked to the persistence of SARS-CoV-2 in the olfactory bulb.

A cautionary note on recall vaccination in ex-COVID-19 subjects (preprint)

Currently approved COVID-19 vaccines based on mRNA or adenovirus require a first jab followed by recall immunization. There is no indication as to whether individuals who have recovered from COVID-19 should be vaccinated, and if so, if they should receive one or two vaccine doses. Here, we tested the antibody response developed after the first dose of the mRNA based vaccine encoding the SARS-CoV-2 full-length spike protein (BNT162b2) in 124 healthcare professionals of which 57 had a previous history of COVID-19 (ExCOVID). Post-vaccine antibodies in ExCOVID individuals increase exponentially within 7-15 days after the first dose compared to naive subjects (p<0.0001). We developed a multivariate Linear Regression (LR) model with l2 regularization to predict the IgG response for SARS-COV-2 vaccine. We found that the antibody response of ExCOVID patients depends on the IgG pre-vaccine titer and on the symptoms that they developed during the disorder, with anosmia/dysgeusia and gastrointestinal disorders being the most significantly positively correlated in the LR. Thus, one vaccine dose is sufficient to induce a good antibody response in ExCOVID subjects. This poses caution for ExCOVID subjects to receive a second jab both because they may have a overreaction of the inflammatory response and also in light of the current vaccine shortage.

IgG serology in health care and administrative staff populations from 7 hospital representative of different exposures to SARS-CoV-2 in Lombardy, Italy (preprint)

Lombardy is one of the regions in Italy most affected by COVID-19. We assessed the diffusion of the virus via testing plasma anti-SARS-CoV-2 IgG antibodies in 3985 employees of 7 different hospitals, located across the Lombardy region in areas with different exposure to the epidemic. Subjects filled an anamnestic questionnaire to self-report on COVID-19 symptoms, co-morbidities, smoking, regular or smart-working, and the exposure to COVID-19-infected individuals. We show that the number of individuals exposed to the virus depended on the geographical area where the hospital was located and ranged between 3 to 43% which correlated with the incidence of COVID-19 in Lombardy. There was a higher prevalence of females than males positive for IgG, however the level of antibodies was similar, suggesting a comparable magnitude of the response. We observed 10% of IgG positive asymptomatic individuals and another 20% with one or two symptoms. 81% of individuals presenting both anosmia/ageusia and fever resulted SARS-CoV-2 infected. IgG positivity correlated with family contacts. In conclusion, the frequency of IgG positivity and SARS-CoV-2 infection is dependent on the geographical exposure to the virus and to extra-hospital exposure.

Impact of anti-androgenic therapies on COVID-19: an observational study in male population from a COVID-19 regional centre of Lombardy (Italy) (preprint)

There are gender differences in susceptibility and vulnerability to the Coronavirus disease 2019 (COVID-19). The S protein of coronaviruses facilitates viral entry into target cells and employs the host cellular serine protease TMPRSS2 for S protein priming. The TMPRSS2 gene expression is responsive to androgen stimulation and it could partially explain gender differences. We tested the hypothesis that men who received 5-Alpha reductase inhibitors (5ARIs) or androgen deprivation therapy (ADT) for prostate cancer could have a different susceptibility to COVID-19. We carried out an observational study on patients who were referred to our COVID-19 regional centre in Lombardy from 1st to 31st March 2020. Data from 421 patients, 137 women (32.54%) and 284 men (67.44%) with laboratory-confirmed COVID-19, were included in this report. Overall 84 patients died: 28 women (33.33%) and 56 men (66.67%). Among men, 12 patients (4.22%) reported assuming 5ARI treatment, and 6 were under ADT. Over 12 patients under 5ARIs, 3 (25%) died; 2 deaths (33%) were reported in patients under ADT. Our findings showed that only 4.22% of the overall population received 5ARI anti-androgen therapy, a percentage, which revealed to be significantly lower (P<0.0001) than what observed in Italian men aged more than 40 years (14.97%).