With vaccines being distributed across the country, it seems like there will be an end to the coronavirus pandemic.
And for that, we have to thank, in part, a Missouri man. Dr. David Curiel and his team at Washington University in St. Louis have been researching mRNA vaccines since 1995. He’s been called the “father” of the Covid-19 vaccine, and technology he worked on has allowed the vaccine to be developed in just a year, instead of several. The two approved vaccines, from Pfizer and Moderna, both work via a genetic molecule called mRNA that’s naturally found in human cells. That mRNA instructs the body to produce a coronavirus protein, called spike. Even though your own body made the spike, it’s recognized as a foreign invader, triggering the body’s infection-fighting antibodies.
Right now, the two approved vaccines both require two shots, spaced weeks apart. But Dr. Curiel is hopeful for another breakthrough, achieved by introducing the mRNA vaccine through the nose. It’s not only less invasive than a needle, but it could be faster-acting and more effective, since the immune response will be in the most-likely site of infection.
We chatted with Dr. Curiel about his work.
How does nasal delivery differ from a shot?
In addition to giving you protective immunity from the infection, it specifically enhances the immunity of the upper respiratory tract. And that may be important to limiting what we call lateral transmission, that is person-to-person transmission. The virus is naturally a respiratory pathogen. So by stimulating immunity at the portal where it normally infects, there is a logical way to accomplish the optimal immune response.
Are there any side effects that the nasal vaccine has?
We haven’t done big enough studies to capture every possible side effect; but, in the limited studies that we’ve done, there have been minimal side effects. So it may be that this is a way to reduce side effects as well.
What happens to the protein the body makes in response to the vaccine?
There’s a process called antigen processing. So the certain cells in your body take that protein and break it down, and they present it to the immune system in a way the immune system can see it. So the protein is consumed as if it were in the process of developing the immune response. It can’t cause an infection or even a pathology based on the one gene.
Does this vaccine protect just you or others as well?
Because it eradicates and sterilizes the upper airway and gets rid of anything that’s there, it should limit your ability to transmit it and protect you from getting the infection.
How does the mRNA intranasal vaccine differ in terms of storage and distribution?
For the Moderna and the Pfizer vaccines, which are mRNA vaccines, the storage requirements are much more stringent than for the adenovirus vaccines. The nasal vaccine is with adenovirus, and no matter how good the mRNA gets, it’s probably not going to be something we can give to as many body sites as we can the adenovirus, which is very stable and very effective.
Will the Covid vaccine be similar to the flu vaccine? Will one have to be vaccinated every year?
It will probably be very analogous because the way the flu vaccine works is through epidemiology and screening. We can anticipate months in advance what will be the makeup of the influenza strain; and, based on that, there’s adequate time to design a vaccine and implement it. So, it’s probably going to be very analogous to that for the SARS-COV-2 virus.
How does the body know to create and fight the protein that is placed in the body?
The body sees the spike protein as if the spike protein were part of the virus. So, it develops antibodies, and some of those antibodies block the portion of the spike protein that is critical for anchoring to the host cells.
When will this vaccine become available?
We started making the virus at the end of February, and our collaborators in India have started a human trial this week. So we’ve gone from an idea to a trial in humans in less than a year. And, their trial will have data, we hope, by the end of March. Based on that data, we’ll be able to do much larger trials to prove the efficacy of the agent.
