Intensity of Humoral Immune Responses, Adverse Reactions, and Post-Vaccination Morbidity after Adenovirus Vector-Based and mRNA Anti-COVID-19 Vaccines

Abstract

The aim of the study was to compare mRNA vaccine BNT162b2 with adenovirus vector- based vaccines in terms of presence of adverse reactions, immunogenicity, and protection against COVID-19. A total of 270 individuals were enrolled, of which 135 were vaccinated with adenovirus vector-based vaccines and compared with 135 age- and sex-matched participants who received the BNT162b2 mRNA vaccine. Serum sampling was performed on all participants on days 21, 42, 90, and 180 following the first dose, to evaluate anti-spike IgG and IgA responses. Antibodies were quantified by chemiluminescent microplate and ELISA assays. We demonstrate that both mRNA and adenovirus vector-based vaccines caused mild side-effects and were effective in inducing adequate antibody responses against SARS-CoV-2, although BNT162b2 was superior concerning the intensity of antibody responses and protection against severe COVID-19. Moreover, we identify that IgG and IgA responses depended primarily on both history of previous COVID-19 infection and vaccination platform used, with individuals immunized with a single-dose vaccine having lower antibody titers over time. Lastly, all vaccine platforms had limited side-effects, with the most frequent pain at the injection site. Our results provide useful information regarding antibody responses after vaccination with different vaccine platforms, which can be useful for public health vaccination strategies.

Specific and off-target immune responses following COVID-19 vaccination with ChAdOx1-S and BNT162b2 vaccines—an exploratory sub-study of the BRACE trial

“…While BNT162b2 and ChAdOx1-S vaccines are designed to induce host cell production of the SARS-CoV-2 spike protein, previous studies have reported differing levels of SARS-CoV-2-specific antibody and T cell responses between the two vaccines. 37 , 46 , 47 , 48 , 49 Consistent with this, our study of healthcare workers showed that those vaccinated with BNT162b2 vaccine had greater SARS-CoV-2-specific IgG and in vitro cytokine responses compared to ChAdOx1-S recipients. Additionally, we observed differences in off-target effects of the two vaccines resulting in differential cytokine responses, particularly to BCG, E. coli , and R848 stimulation, 28 days after the second vaccine dose.…”

Dynamics of Anti-SARS-CoV-2 IgA and IgG Responses and Their Protective Effect against Fatal Disease after Booster COVID-19 Vaccination

“…The duration of the follow-up period was defined as the day of the first recorded dose of initial vaccination until day 90 following the last recorded third booster dose. Only data on day 90 and 180 following the first and second booster doses and on day 21 and 90 following the third booster dose were analyzed for IgG antibodies; outcomes derived from analysis of previous sampling days have already been published [ 8 , 9 ]. Regarding IgA antibodies, only data on day 90 were included because on this day individuals already display low IgA antibody levels, and their titers are expected to further decrease after day 90 [ 8 ].…”

A Clinical Update on SARS-CoV-2: Pathology and Development of Potential Inhibitors

“…The use of the mAbs Bebtelovimab and Evusheld (tixagevimab co-packaged with cilgavimab) that target SARS-CoV-2 is permitted by an EUA [44]. SARS-CoV-2 can mutate over time, like other contagious organisms, leading to genetic heterogeneity in the population of circulating viral strains [45,46]. Certain variations have the potential to result in resistance to one or more of the mAb treatments approved to treat COVID-19 [46].…”