I’ve seen an idea on a number of TV shows or movies. There’s someone who is immune to the ongoing pandemic. So, the scientist takes their blood (?) and does something (?) and presto! We have a vaccine.
Is this really how it works? I guess I’m not understanding what exactly the scientist is supposed to be doing. What are the steps to go from “here’s this immune person” to “we have a vaccine”?
Or is this all just TV nonsense?
I’m no expert, and I’m sure TV is hardly the place to pick up realism in any regard. But I’m sure they’re collecting the immune patient’s antibodies, then incubating more of them to distribute to the sick. I’ve heard if them using eggs for this process.
Microbiologists?
There’s the use of blood serum from a survivor to help an individual via a transfusion. That’s been done in one case with the recent Ebola outbreak. In fact, it’s similar to the now-famous Zmapp drug (which is monoclonal antibodies, rather than polyclonal, and from mice rather than humans)
This isn’t really what is traditionally considered a “vaccine”, which is usually something designed to get the body to produce its own antibodies (usually the virus in some sort of weakened state)
Not my area of expertise, but that’s not how any vaccines that I am aware of were developed.
Most I think come from microorganisms that have been damaged in some way, through things like heat or chemicals. You want enough of the original microorganism present to trigger your immune system to produce antibodies but you don’t want the dangerous parts of the microorganism to survive.
Another method is to mix strains of the microorganism until you end up with a microorganism that is basically the same thing, something that triggers the production of antibodies without being dangerous.
The flu, polio, hepatitis, measles, and tuberculosis vaccines all involve damaged microorganisms that trigger your body’s own immune system to produce antibodies.
I’ve never heard of a vaccine that inserts antibodies from someone else into your system.
You’re confusing active immunity (vaccinations) with passive immunity (globulin infusion.)
Most vaccinations induce active immunity by promoting the development of antibody in the recipient, a response which is expected to be durable. Passive immunization, which usually involves the administration of a globulin product, produces transient immunity for a specific exposure through the transfer of antibody directly. If a person gets stuck with a known hepatitis B-contaminated needle, and hasn’t been vaccinated for Hep B in the past, they may get an infusion of Hepatitis B immune globulin, harvested from a patient who is known to be immune. This will knock out any Hep B virus trying to take hold at that moment, but won’t confer future immunity.
The goal of active immunization of a vaccine or toxoid is to stimulate the host to produce a primary immune response (usually by inducing B-cell proliferation, antibody response, and T-cell sensitization). If an individual is subsequently exposed to the pathogen against which the vaccine is directed, the exposure results in a secondary response that includes increased proliferation of B cells and formation of antibodies. The secondary response protects the individual from developing disease, ideally for life.
So a vaccine needs to contain a molecule/molecules (to serve as an antigen) that causes a body to develop antibodies to the desired pathogen (be it hepatitis B virus, pertussis bacteria, etc.) In the past, inactive or killed viruses have been used, along with fragments of viral coats or bacterial walls. Nowadays, other novel approaches may used targeting molecules resembling virus or cell interiors.
The tricky part is finding the right antigen to induce the proper immune response without infecting or otherwise seriously damaging the patient.
Credit to UpToDate.com for a lot of info in this post.
So that means its just TV show nonsense?
Just TV show nonesense. The original Salk polio vaccine consisted of killed viruses. Later the Sabin vaccine, which is more protective consisted of weakened live virus. I am not sure how they did that. But there is a theoretical possibility that it could mutate to a more dangerous form or that an individual might be so sensitive as to suffer a real infection anyway. I don’t know if either of those has ever happened.
The anti-vaxxers of today should only live through a polio epidemic.
You CAN get useful molecules from the plasma of an infected patient, like interferon and antibodies, and these molecules can be used to help another infected patient fight off an infection from the same (antibodies) or a different (interferon) virus. However, these are more like drugs - their action is purely temporary and lasts only as long as the molecules are in the patient’s system. They are NOT vaccines, and do NOT provide lasting immunity.
Now, if you wanted to make a vaccine, you could start by isolating virus particles from an infected patient, particularly if it’s an unidentified or completely new virus. But that’s just step one out of about forty million.
In fact, paralysis from Sabin vaccine-derived poliovirus does happen. Just before the United States switched back to injectable polio vaccine from oral poilo vaccine, most of the polio cases in the United States were from the vaccine. The vaccine virus itself is dangerous to people with certain severe immune deficiencies, and the vaccine virus can revert to virus dangerous to anyone
Nevertheless, the oral vaccine is still used in many countries. There are a couple of reasons why the oral vaccine has been and in some places still is used is used in place of the injectable: 1) the logistics of injecting people are formidable, compared with the logistics of squirting drops into mouths, and 2) the Sabin virus, being live, can pass from one gut to another, thereby immunizing persons who have not been vaccinated. Considering how devastating polio is, and how hard it has been to eradicate it, these concerns cannot be ignored.