Improved vaccine for Bacillus anthracis has elevated resistance to premature degradation through increased thermal and structural stability.
Bacillus anthracis, more commonly known as Anthrax, is a bacterial toxin and is regarded to be a potential
threat for biowarfare or bioterrorism. Exposure to aerosolized B. anthracis spores is toxic and lethal to
humans and mammals, and can have devastating consequences if ever used as an agent for bioterrorism.
Anthrax has been used as a weapon around the world for nearly a
century and is classified by the CDC as a Tier 1 agent. In 2001,
powdered Anthrax spores were placed into letters and mailed
through the U.S. Postal System. A total of 22 people were infected
with Anthrax and five casualties. The spores can easily be found in
nature or produced in a lab, and can survive for long periods in
harsh environments. The microscopic spores can be easily placed
in powders, sprays, food, and water, and are often unable to be seen,
smelled, or tasted. The infection can occur in four forms: skin,
inhalation, intestinal, and injection. Symptoms are different for
each infection type, and range from skin lesions, abscess
formation, fever, chest pain, vomiting, and abdominal pain.
LIMITATIONS OF THE CURRENT VACCINE:
The only licensed human vaccine in the U.S. is
Anthrax Vaccine Adsorbed (AVA), commercially
known as BioThrax. FDA vaccination requirements
for pre-exposure to Anthrax involve a primary
series of three doses and require a booster series
at yearly intervals following the primary series.
The vaccine must be stored and refrigerated at
2 ⁰C – 8 ⁰C (36 ⁰F – 46 ⁰F) to retain efficacy.
Potency is reduced each time the vaccine is exposed
to improper conditions. Without specialized transport
with cold chain storage to keep the vaccine between
2 ⁰C – 8 ⁰C, wide distribution is a challenge. Any period
of temperature excursion will result in the physical or
chemical degradation of the protein structures that are
critical for inducing protective immunity. Improper
storage of the vaccine at the necessary conditions will
result in a complete loss of efficacy and be rendered
useless.
NEW VACCINE COMPLEX UNDETERRED BY PREVIOUS RESTRICTIONS:
Protective antigen is the protein responsible for transporting Lethal Factor
(LF) and Edema Factor (EF) into the host cell. Reseachers developed an
advanced Protective Antigen Complex to elicit an immunogenic response
in a subject and induce protective immunity. The complex has elevated
resistance to PA folding and pore formation, preventing LF and EF from
comprising immunity in the cell. The invented complex also raises the
thermal stabilty by at least 20 ⁰C compared to the prior serum. By acheiving
storage of the vaccine at 25 ⁰C , this eliminates the necessity for specialized
transport containers with temperature control. This will allow for the wide
distribution of the vaccine, making it easily accessible in underdevloped
areas with scarce medical resources.