Vaccination efforts are widespread in many countries around the world. One of the authorized vaccines is the BNT162b2 vaccine or the Pfizer-BioNTech vaccine, a acidic ribonucleic acid (mRNA) vaccine against severe respiratory coronavirus syndrome 2 (SARS-CoV-2), the virus that causes the coronavirus disease (COVID-19).
Researchers at Pitié Salpêtrière Hospital, Department of Virology, Paris, France, in BNT162b2 vaccine participants who received two doses, concluded that their serum was at least neutral titer against all three SARS modifications. -CoV-2.
The results of the study, which appeared in the pre-print server bioRxiv *, recommend specific humoral protective action on UK or South African variables after two doses of the mRNA vaccine.
Study background
One of the disadvantages of vaccine development is its ability to protect against the muta virus. It has taken years to develop effective and safe vaccines against SARS-CoV-2, and if new variants are released, it may take longer to create updated vaccines.
Therefore, scientists wanted to find out if the developed and current vaccines can protect against these new variables.
As of October 2020, three new mutations have emerged from the Spike (S) protein-encoding gene of SARS-CoV-2. The new changes include the United Kingdom (UK) B.1.1.7 variable with many changes in the fall of 2020 and the South African version called B.1.351. Another recent variation has emerged, called the Brazilian or P.1 variant.
The new changes have caused skyrocketing issues as they appear to be more mobile. Recent studies have also shown that UK variability can cause more serious illness. However, further studies are ongoing.
These changes harbor a distinct pattern of depletion and mutations, leading to amino acid uptake at key sites in the S Receptor Link Area (RBD).
As vaccination efforts continue, the question remained as to whether these variants could avoid the neutral antibodies (NAb) induced by the mRNA vaccine.
Two recent studies have shown that only some mutations from the UK and US showed a weaker neutralization potential of vaccine-derived serum. Another study tested pseudoviruses SARS-CoV-2-S containing either ancestral Wuhan reference strain or UK spike protein with sera extracted by BNT162b2 vaccine showing slightly less reserved neutral titers against pseudovirus UK. However, none of these studies were performed on clinical isolates that contained full genomic mutations of both strands.
The study
To answer the question, the researchers performed a virus-neutralization (VNT) test on sera from health care workers with either a previous infectious disease of COVID-19, the second largest D614G strain, the UK snoring, and US snoring.
Two sets of health care workers were observed – a convalescent group of 15 participants with COVID-19 and a vaccination group of 29 participants with no history of COVID-19.
The team collected convalescent sera six months after symptoms from health care workers with a transversease-polymerase chain test (RT-PCR). They also collected sera from those who received the vaccine three weeks after the first dose and seven days after the increase.
From there, the team used the immunoglobulin G (IgG) SARS-CoV-2 anti-nucleocapsid (N) assay, known as the SARS-CoV-2 IgG Alinity assay by Abbott Laboratories. Further, the team also obtained and SARS-CoV-2 clinical isolation of D614G, RA, and USA The team then determined the neutral activity of the various serum samples.
The team found that the majority of sera found contain neutral antibody titers, suggesting a moderate humoral defense against one of the two variants. However, six months after infection, some HCW showed no neutral activity against U.S. strain.
The findings of the study showed that even those with moderate COVID-19 infection may still need to be vaccinated for protection.
The team suggests that further studies are needed to determine the vaccine-induced SARS-CoV-2 correlations of immunization based on Nab and T cell responses.
They suggested that further studies are needed to determine that SARS-CoV-2 binds 157 immunizations with a vaccine based on NAb and T cell responses.
“The long-term assessment of vaccine-induced NAb survival is needed to assess the stability of protection against SARS-CoV-2 changes,” the team said.
* Important message
bioRxiv publish preliminary scientific reports that are not peer-reviewed and, therefore, should not be seen as final, guiding health-related clinical / behavioral practice, or be treated as information established.