Vaccines and bacterial vectors.
The main aim of this research is to change the route of delivery and effectiveness of vaccinations to the human population.
Genetics and Biology
· Using live bacteria as a vector to carry vaccines into the human body
· Using specific plasmids that create a immune response in the human body and in turn vaccinating and building immunity in humans
· Using live bacteria as a vector combined with recombinant bacteria using techniques such as PCR and electrophoresis.
· What you are essentially doing is infecting a host with bacteria leading to research into suitable bacteria.
· One option is using GRAS (generally recognised as safe) bacteria. Which don’t readily replicate once in a mammalian host. These are readily used in the food industry to preserve food products.
· Lactobacillus is one of the bacteria used by the food industry and is considered a GRAS bacteria. Some lactobacillus strains are know to colonise in the human gut, exhibiting probiotic health-promoting activities. This has a disadvantage that producing a immune response in the guts is physiologically difficult.
· Enteric pathogens have shown promise and most of the research has been in this area. Were there is a higher surface area, the potential create a sufficient immune response.
· Currently there is one recombinant bacterium that is successful in creating immunity for tuberculosis. This bacterium is known as BCG bacteria (Bacille Calmette-Guerin). Which can delivered nasal or orally and has been proven to work. Which then leads to bacteria colonizing in the lungs preventing future infection.
· There are lots of others that are undergoing testing and clinical trial, but shows that this is all possible.
Pros and cons
· Cheep – theoretically once this is possible it will require no health professional to administer vaccinations.
· Save’s time - Vaccines can be cultured/grown in about two weeks, currently takes about a month to produce vaccination
· Convenient – its can be as simple as going to your pharmacist with a script from the doctor and ingesting recombinant bacteria from the routes of administration available. Oral, intranasal, rectally.
· Essentially what you are doing is infecting patient with live recombinant bacteria, negative side effects will occur
· From this there will be lots of safety requirement and guidelines for suitable bacteria
· There are known side effects with a live vector bacterium. Therefore a risk benefit for human health needs to be established, choosing bacteria that will produce minimal side effect but can still produce the desired immune response, this is the biggest obstacle at the moment.