Many vaccines have short shelf lives, or are unstable unless they are kept in the fridge, which makes storage difficult, especially in warm climates. A microemulsion vaccine carrier, developed by U.S. Army Maj. Jean M. Muderhwa, has the potential the improve the stability of vaccines.
Emulsions are mixtures of liquids such as oil and water. Muderhwa's microemulsion is a simple one, made of very small droplets of oil suspended in water, with glycerol and surfactants to stabilize the emulsion, and an aluminum adjuvant-adsorbed protein, used in influenza vaccines, to stimulate an immune response.
Microemulsions have been used in drug delivery, but their use in vaccines seems to be new, and could be used as a tool to investigate the effect of the size of the droplets on the immune response.
"Another part of the presentation is for the future--to tell people that these products can be used as a tool to investigate the effect of the surface area on the immune response," Muderhwa explained. "If you make the molecules smaller and smaller and smaller, what happens? What happens if you increase the surface area? It will be interesting for research purposes to see the effects when the surface area increases on the immune response using this compound."
Muderhwa, who is based at the Brooke Army Medical Center (BAMC) and San Antonio Military Medical Center (SAMMC), presented his data at the American Society for Biochemistry and Molecular Biology's annual meeting, which is part of FASEB's Experimental Biology 2012. Animal studies are planned.
Soligenix ($SNGX) is developing its ThermoVax technology to improve stability to extremes of temperature and other environmental stresses, and results show that a vaccine formulated using this technology remains active even after more than three months at high temperatures.
Carriers and formulations that could extend the shelf life of vaccines, perhaps even for as long as 10 or 20 years, would help preserve vaccines in hot climates, or in areas where refrigeration is hard to find. They would also allow the stockpiling of vaccines for rare infectious diseases, or against potential pandemic outbreaks such as swine flu or bird flu.
- read the press release from ASBMB
- see the press release from Soligenix