University Of Colorado Study Warns That The Soon To Be Globally Dominant Lambda Variant Is More Vaccine Evasive Than The Delta Variant!
A new study by researchers from the Department of Immunology and Genomic Medicine, National Jewish Health-Denver and the Department of Immunology and Microbiology, School of Medicine, Anschutz Medical Center, University of Colorado-USA along with scientists from the State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agriculture University, Beijing-China warns that the soon to be globally dominant Lambda variant is more vaccine immune evasive that the current dominant Delta variants.
Worryingly the newly emerging variants of SARS-CoV-2 from India (Delta variant) and South America (Lambda variant) have led to a higher infection rate of either vaccinated or unvaccinated people.
The study team found that sera from Pfizer-BioNTech vaccine maintains high reactivity toward the receptor binding domain (RBD) of Delta variant but alarmingly it drops dramatically toward that of Lambda variant.
Furthermore, the overall titer of antibodies of Pfizer-BioNTech vaccinated individuals drops 3-fold after 6 months, which could be one of major reasons for breakthrough infections, emphasizing the importance of potential third boost shot.
Although a therapeutic antibody, Bamlanivimab, decreases binding affinity to Delta variant by ~20 fold, it fully lost binding to Lambda variant.
Structural modeling of complexes of RBD with human receptor, Angiotensin Converting Enzyme 2 (ACE2), and Bamlanivimab suggest the potential basis of the change of binding. The study findings suggest possible danger and a potential surge of Lambda variant in near future
The study findings were published on a preprint server and are currently being peer reviewed. https://www.biorxiv.org/content/10.1101/2021.08.25.457692v1
The Lambda variant is gradually getting a foothold in any countries and its spread is gaining momentum.. Also other new variants similar in nature to the Lambda variant could emerge overtime. Thailand Medical News first warned about the emergence of the Lambda variant on the 6th
Of July, way before any of the stupid American, British or Thai mainstream media were covering it. The same goes for the Mu variant. https://www.thailandmedical.news/news/breaking-news-forget-about-delta-variant,-new-fast-spreading-lambda-variant-is-vaccine-proof-and-guarantees-that-most-will-develop-disease-severity-an
The Chinese SARS-CoV-2 coronavirus which made its debut in Wuhan, China in December 2019 has to date killed
more than 4.6 million people globally according to official figures. (Actual death figures including excess deaths could be as high as eight-fold!)
The Chinese coronavirus has also infected more than 221 million people worldwide (WHO and the US CDC have publicly admitted that these figures could be as high as ten-fold!).
Hence it is quite apparent the World is facing a two pronged health crisis as cases for Long COVDI are already starting to mount!
Unfortunately the COVID-19 pandemic continues to affect more people globally, while certain health bodies and agencies are highlighting the need for widespread and rapid use of effective vaccines.
While several vaccines have been approved in the USA for emergency use, the increasing number of SARS-CoV-2 spike variants of concern emerging in different parts of the world raises major concerns about the continued efficacy of the currently approved vaccines.
Studies have shown that over 90% of neutralizing anti-SARS-CoV-2 antibodies taken from COVID-19 patients and vaccinated individuals act on the receptor-binding domain (RBD) of the SARS-CoV-2 Spike protein. Monoclonal antibodies developed by different companies specifically target the Spike protein and have been approved for emergency use by the FDA.
It has been found that the original (wildtype) SARS-CoV-2 virus that was first detected in Wuhan, China, has around 6 times higher binding affinity toward RBD and angiotensin-converting enzyme 2 (ACE2) ie the host cell receptor that facilitates viral entry, compared to SARS-CoV-1.
Studies have also shown that each SARS-CoV-2 variant of concern has some unique mutations and features that help them become the dominant strain in some places.
Alarmingly studies have shown that newly emerging SARS-CoV-2 variants from India (Delta) variant and South America (Lambda) variant have higher infection rates in vaccinated as well as unvaccinated people.
The study team insists that a better understanding of the underlying mechanisms that render these variants more infectious and vaccine-resistant is essential for battling the pandemic.
The study team analyzed the potential factors that confer high infectivity and immune resistance on the Delta and Lambda variants.
Their study findings alarmingly also suggests that the Lambda variant could become dominant in future surges.
The researchers found that sera from the Pfizer-BioNTech vaccinees had high reactivity toward the receptor-binding domain (RBD) of the Delta variant and poor reactivity toward RBD of the Lambda variant.
Furthermnore, the overall antibodies titers of individuals vaccinated with Pfizer-BioNTech dropped 3-fold 6 months after vaccination. This could be one major reason for breakthrough infections, which emphasizes the significance of a third booster shot.
Also the overall titer of antibodies of Pfizer-BioNTech vaccinated individuals drops 3-fold after 6 months, which could be one of major reasons for breakthrough infections, emphasizing the importance of potential third boost shot.
Presently approved vaccines are effective against the Delta variant in the USA
Biochemical analysis showed that the Delta variant slightly increases ACE2 binding compared to the wildtype virus.
The study team also found that the therapeutic antibody, Bamlanivimab, decreases binding affinity to Delta variant by about 20 fold, it fully lost binding to Lambda variant.
Structural modeling of RBD complexes with the human host cell receptor, ACE2, and Bamlanivimab show the potential basis of binding changes.
The study findings also demonstrate possible danger and an increase in the Lambda variant in the near future.
The study team also adds, “It becomes clear that the furin site and high binding affinity between RBD and ACE2 are responsible for the high infectivity while mutations mostly within the RBD accounting for the escaping of the virus. One intriguing question is why above 90% broadly neutralizing antibodies either from COVID-19 patients or vaccinated people are against only RBD of the spike. The production of broadly neutralizing antibodies from B Cells is regulated by T cells, and it suggests that the protecting T cells from COVID-19 patients or vaccinated people are likely limited to the RBD portion as well. One most possible explanation is that the four disulfide bridges within RBD, which stabilize the three-dimension structure of RBD, confer the domain as a dominant antigen responsible for host immune responses. Learning from this fact, it could be a promising strategy to introduce artificial disulfide bridges into some conserved regions within the spike protein, such as the proximate membrane fusion region, the N-terminal region, etc, to expand usage of antigens of the entire spike protein for immune response to trigger wider production of broadly neutralizing antibodies as well as T cell protection.”
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