A future vaccine might finally have hope to be in the works, as inspired by recent lab findings.
COVID-19 vaccines have helped keep people from getting severely sick and perishing from the virus. Still, they’ve required additional boosters to keep up with all the coronavirus variants that have popped up.
Currently, researchers in the US have uncovered an antibody that neutralises all known COVID-19 variants. The antibody, SP1-77, is the outcome of a collective effort from Boston Children’s Hospital and Duke University researchers. Developments from mouse studies they’ve conducted were recently published in the journal Science Immunology, and they look encouraging [1].
But what does it mean to have an antibody that can neutralise all known variants of COVID-19? And what kind of bearing will this have on vaccines in the future?
What is SP1-77?
SP1-77 is an antibody generated by researchers that so far can counteract all forms of SARS-CoV-2, the virus that causes COVID-19. It was created after researchers initially modified a mouse model to look broadly neutralising antibodies to HIV, which also mutates [2].
The mice used in the study have built-in human immune systems that mimic how our immune systems develop more useful antibodies when subjected to a pathogen. The researchers added two human gene segments into the mice, creating a range of antibodies humans might produce.
The mice were afterwards exposed to SARS-CoV-2’s spike protein – which the virus manipulates to latch onto your cells and produced nine families of antibodies hooked to the spike protein to neutralise it. The antibodies were tested and one, SP1-77, could cancel Alpha, Beta, Gamma, Delta and all Omicron strains – including the current circulating ones of COVID-19 [3, 4].
The antibody works slightly differently from many of the antibodies people make to vaccines. SARS-CoV-2 has initially attach to ACE2 receptors in your cells to infect you. The current COVID-19 vaccines block this binding by adhering to the spike protein’s receptor-binding domain (RBD) at certain spots, according to a media release from Boston Children’s Hospital [5].
The SP1-77 antibody also latches on to the RBD but doesn’t deter the virus from binding to ACE2 receptors. It intercepts the virus from combining its outer membrane with your cells’, which is what needs to happen to make you sick.
What does this indicate for future COVID-19 treatments and vaccines?
Although still unclear, it’s noteworthy that this research was done in mice, not humans – although studies on the antibody are ongoing.
The study is in early-stage proof-of-concept work to illustrate that broadly neutralising antibodies can be generated using a mouse model. If reproduced and developed, such work could form the foundation of new monoclonal antibody products and a vaccine.
Experts say a vaccine that could take out all variants of COVID-19 would be gladly received. “We’d love to have a vaccine that is active against all circulating variants, including those yet to come,” according to Thomas Russo, MD, professor and chief of infectious disease at the University at Buffalo in New York. “It’s the holy grail of vaccines.”
That could mean that you would only have to get a COVID-19 shot or booster annually or even less, depending on how long protection from the vaccine lasted, Russo aadds. The researchers applied for a patent for the SP1-77 antibody and mouse model used to create it and plan to construct something that the general public can use if all goes well.
Another breakthrough from a team in Israel
In another study, Israeli scientists say they have identified antibodies that are so powerful in neutralising the coronavirus that they could take out the need for more vaccine boosters [6].
A research team at Tel Aviv University tested numerous antibodies and found that two, in particular, neutralise all known strains of the coronavirus, including Delta and Omicron, in a lab setting.
Antibody infusions are used to treat some coronavirus patients. According to Microbiologist Dr Natalia Freund, who directed the new study, said the antibodies encountered could be utilised to develop a significantly potent infusion.
Relative to performance in lab conditions, the antibodies could supply the supplementary protection that currently comes from booster shots, she said, counting that this could potentially make additional ones redundant for vaccinated individuals.
COVID-19 infection can bring serious illness, and it’s known that supplying antibodies in the initial days after infection can stop the spread of the virus. “It is possible that by using effective antibody treatment, we will not have to provide booster doses to the entire population each time there is a new variant,” Freund said.
In addition, on a technical level, the accomplishment of the two antibodies appears to be because they bind to a distinct part of the coronavirus spike protein than most others. Freund’s latest study, newly peer-reviewed and published in Communications Biology, comes from analyses that began in her lab in October 2020 [7, 8].
Collaborating with doctoral students Michael Mor and Ruofan Lee, she sequenced the B immune system cells from the blood of people who had recuperated from the original COVID strain in Israel and isolated nine antibodies that the patients produced. The top two antibodies have were tested against various variants and performed well against all of them.
TAU-1109 and TAU-2310
According to their findings, the efficacy of the first antibody, TAU-1109, in neutralising the Omicron strain is 92 per cent, and against the Delta strain, 90 per cent. Meanwhile, the second antibody, TAU-2310, negates the Omicron variant with an efficacy of 84 per cent and Delta with 97 per cent.
The antibodies are called TAU because they were identified at Tel Aviv University. To guarantee that her lab work was done accurately, Freund sent the antibodies to have their effectiveness opposite live viruses checked in laboratory cultures at the University of California San Diego, and for additional testing at Bar-Ilan University’s medicine faculty in Galilee. These studies substantiated her results.
Freund said that antibodies indeed provide strong protection, as they prevent infection straight after recovery, but they wane, and immunity decreases. In her view, this makes it rational to support artificially boosting antibodies, and she hopes to do this with the antibodies identified.
“For reasons, we still don’t yet fully understand, the level of antibodies against COVID-19 declines significantly after three months,” she explained. This is why we see people getting infected repeatedly, even after being vaccinated thrice.
[1] https://www.science.org/doi/10.1126/sciimmunol.add5446
[2] https://www.prevention.com/health/a41092334/antibody-neutralize-covid-variants/
[3] https://www.prevention.com/health/a38400888/omicron-vs-delta-covid-19-variant
comparison/
[4] https://www.prevention.com/health/health-conditions/a40179304/omicron-ba-4-ba-5-new-variants-covid-19/
[5] https://answers.childrenshospital.org/covid-19-neutralizing-antibody/
[6] https://www.timesofisrael.com/two-antibodies-identified-in-israel-can-fight-all-known-covid-strains-study-finds/
[7] https://www.nature.com/articles/s42003-022-03739-5
[8] https://www.timesofisrael.com/hoping-to-outdo-trumps-miracle-cure-israelis-develop-new-antibody-cocktail/
