Some interesting research done in Dr. James R. Baker Jr.’s lab at University of Michigan was reported this week. Baker is the Director of the University’s Nanotechnology Institute for Medicine and Biological Sciences.
Baker, an immunologist, developed a nontoxic nanoemulsion made of soybean oil droplets that carry antigens into the nasal mucosa where they stimulate an immune response. (See description of the vaccine project here.) His nanoemulsion research was funded by DARPA’s Unconventional Pathogen Countermeasures Program, while the vaccine development was funded by the NIH.
As Baker’s research projects page explains, there are some serious drawbacks to the current vaccines we have for both anthrax and smallpox, and a completely harmless soybean oil carrier could solve a lot of problems.
As current approaches to vaccination for agents such as small pox and anthrax have drawbacks due to the use of live virus, complex vaccination protocols or the addition of unacceptable adjuvants (for humans), we are currently determining whether mixing nanoemulsion with vaccinia will provide a rapid and effective means for a killed vaccinia virus vaccine. We will initially test the ability of the nanoemulsion to inactivate vaccinia virus. We will then evaluate the immunogenicity of vaccinia virus mixed with nanoemulsion and placed either in the nares or injected intradermal or intramuscularly. After the immune responses have been characterized, we will then determine if mice immunized with vaccinia/nanoemulsion are protected from infection with live vaccinia virus. These studies should determine the feasibility of a nanoemulsion-based killed vaccinia virus vaccine, and provide a basis for subsequent efficacy studies using primate models of small pox.
We plan to study the efficacy of nanoemulsion mixed with protective antigen of B. anthracis (PA) for the development of protective immunity against inhalation or injection challenge with either live bacilli or spores. Similar studies on the efficacy of nanoemulsion mixed with HIV and other agents are in progress.
I’ve not had the anthrax shots, luckily, but friends tell me it’s a royal pain and there are all those boosters. It could be that a series might be needed with the nasal vaccine, too, but it would be a more pleasant experience, I’m sure. Animal studies indicated that for inhalational anthrax, the nasal vaccine was partially effective but it did extend survival time. From New Scientist:
An exposure of 10 times the lethal dose killed 30% of the guinea pigs, and 100 times the lethal dose killed 60%. This is about the same level of effectiveness as that offered by conventional anthrax vaccines, which were developed 30 years ago.
The vaccine also extended survival time by between three and five days, which in humans might allow enough time for other treatments to work.
Extending survival time is very important now that a treatment’s been developed—remember ABThrax, which I blogged about here.
Baker’s lab is also working on research with dendrimers for targeted delivery of whatever-you-want, a project I find quite a bit more intriguing in all sorts of ways than the nasal vaccine.
Incidentally, I heard Baker speak on biosecurity a couple of years ago. He discussed a variety of examples of research that highlighted the range of potential future biothreats. He emphasized the need to educate health care professionals and that traditional bioagents found in nature might be missed by doctors because they cause different symptoms when delivered as a weapon. He was supportive of developing biosecurity measures that have dual uses, in other words are good public health measures whether someone attacks us or not.
And that seems to be the direction we are attempting to stumble in.