World’s First mRNA Vaccine Developed in Israel

An mRNA vaccine that is 100% effective against a kind of bacteria that is fatal to humans has been created for the first time ever by a team of researchers from Tel Aviv University and the Israel Center for Biological Research.
The study, which used an animal model, showed that all treated animals had complete immunity to the germs. The researchers claim that their innovative approach can facilitate the quick production of vaccinations that are effective against bacterial infections, particularly those brought on by germs that are resistant to antibiotics, for instance in the event of a pandemic that is spreading quickly.

The study was led by Tel Aviv University’s Dr. Edo Kon and Prof. Dan Peer, VP for R&D and Head of the Laboratory of Precision Nano-Medicine at the Shmunis School of Biomedicine and Cancer Research, in collaboration with researchers from the Israel Institute for Biological Research: Dr. Yinon Levy, Uri Elia, Dr. Emanuelle Mamroud, and Dr. Ofer Cohen. The study’s results were published in the journal Science Advances.

Edo Kon explains, “So far mRNA vaccines, such as the COVID-19 vaccines familiar to all of us, were assumed to be effective against viruses but not against bacteria. The great advantage of these vaccines, in addition to their effectiveness, is the ability to develop them very quickly: once the genetic sequence of the virus SARS-CoV2 (COVID-19) was published, it took only 63 days to begin the first clinical trial. However, until now scientists believed that mRNA vaccines against bacteria were biologically undoable. In our study, we proved that it is in fact possible to develop 100%-effective mRNA vaccines for deadly bacteria.”

According to the researchers, viruses need external (host) cells to reproduce. A virus uses our cells as a factory to produce viral proteins based on its own genetic material, i.e. replicates of itself, by inserting its own mRNA molecule into a human cell. This similar molecule is created in the lab for mRNA vaccinations, which are subsequently encased in lipid nanoparticles that resemble human cell membranes. The lipids from the vaccine adhere to our cells after injection, which causes the cells to create viral proteins. When the immune system becomes accustomed to these proteins, it gains knowledge about how to defend our bodies from actual virus exposure.

Kon adds, “Since viruses produce their proteins inside our cells, the proteins translated from the viral genetic sequence are similar to those translated from the lab-synthesized mRNA. Bacteria, however, are a whole different story: They don’t need our cells to produce their own proteins. And since the evolutions of humans and bacteria are quite different from one another, proteins produced in bacteria can be different from those produced in human cells, even when based on the same genetic sequence.

“Researchers have tried to synthesize bacterial proteins in human cells, but exposure to these proteins resulted in low antibodies and a general lack of protective immune effect, in our bodies. This is because, even though the proteins produced in the bacteria are essentially identical to those synthesized in the lab, being based on the same ‘manufacturing instructions,’ those produced in human cells undergo significant changes, like the addition of sugars, when secreted from the human cell.

“To address this problem, we developed methods to secrete the bacterial proteins while bypassing the classical secretion pathways, which are problematic for this application. The result was a significant immune response, with the immune system identifying the proteins in the vaccine as immunogenic bacterial proteins. To enhance the bacterial protein’s stability and make sure that it does not disintegrate too quickly inside the body, we buttressed it with a section of human protein. By combining the two breakthrough strategies we obtained a full immune response.”

Prof. Peer stated, “There are many pathogenic bacteria for which we have no vaccines. Moreover, due to excessive use of antibiotics over the last few decades, many bacteria have developed resistance to antibiotics, reducing the effectiveness of these important drugs. Consequently, antibiotic-resistant bacteria already pose a real threat to human health worldwide. Developing a new type of vaccine may provide an answer to this global problem.

“In our study we tested our novel mRNA vaccine in animals infected with a deadly bacterium. Within a week, all unvaccinated animals died, while those vaccinated with our vaccine remained alive and well. Moreover, in one of our vaccination methods, one dose provided full protection just two weeks after it was administered. The ability to provide full protection with just one dose is crucial for protection against future outbreaks of fast-spreading bacterial pandemics. It is important to note that the COVID-19 vaccine was developed so quickly because it relied on years of research on mRNA vaccines for similar viruses. If tomorrow we face some kind of bacterial pandemic, our study will provide a pathway for quickly developing safe and effective mRNA vaccines.

Source Link