Multimedia Reporting (Kuhr-Musser)

A University of Kansas professor is working on an innovative new vaccine that may make it easier to immunize people in the event of an anthrax attack.

In January 2006 Russell Middaugh, professor of pharmaceutical chemistry at the University of Kansas, published a paper along with colleagues at private and government labs on the development of a powdered anthrax vaccine capable of being sprayed into the nose rather than injected into the muscle.

Laboratory tests confirm the effectiveness of the powdered vaccine on laboratory mice, and human testing has occurred on a limited basis.

“Tests on humans look encouraging,” Middaugh said, “you rely on the data you have, but you will only know if it works on the day you experience a terrorist attack.”

FluMist is prepackaged in a single-use unit that is sprayed into the patient’s nose either by a doctor or nurse. Middaugh hopes a similar delivery system would provide a more effective way for the mass immunization of a population exposed to anthrax.

“Vaccines are best absorbed by the same method we absorb bacteria,” Middaugh said, “which is what made the nose so attractive.”

The idea behind vaccines has changed little since Edward Jenner experimented with them in the late 18th century. Jenner discovered that if a patient were injected with a weak dose of a virus, the body would naturally build up antibodies against it and be resistant to further infection. Intramuscular injection by needle was the method used by Jenner, and still remains the most common delivery method for vaccines today.

To understand the innovative new powdered vaccine, one must first understand the anthrax virus and the problems with the old vaccine.

Anthrax is a combination of three different proteins: edema factor (EF), lethal factor (LF), and protective antigen (PA). The three proteins are non-toxic when separate, but when either LF or EF combine with PA, it acts a medium for the other proteins to enter the human cell with fatal outcomes. The anthrax vaccine is an injection of the PA protein that causes the body to build up a natural immunity. The LF and EF proteins are then unable to bond with the PA protein and enter the cells of the body.

The problem with the current liquid anthrax vaccine is it contains varying amounts of natural PA, Because of this, the current vaccine must be administered six times over a year and a half in order to be fully protected.

Middaugh synthesized a synthetic form of the PA protein called recombinant protective antigen (rPA). This new form standardizes the vaccines strength and eliminates the need for multiple vaccinations.
In synthesizing the rPA, Middaugh was not only able to develop a more consistent, uniform dose, but he also improved the shelf life of the vaccine.

A magnified view of the rPA protein in its powdered form.

Heat destroys the liquid vaccine. The liquid vaccine retained only 15 percent of its potency after 15 days at 77 degrees Fahrenheit and was unusable after just one day at 104 degrees, Middaugh found.
He synthesized a powdered version that after retained 90% of its potency after 29 days at both temperatures.

These findings suggest the powdered vaccine would have the ability to be shipped worldwide and withstand long period of storage with little maintenance. This would be especially useful in developing nations where refrigeration and money are scarce.

The powdered vaccine is still several years away from mass production, during which time more research will be done to further refine the formula and delivery methods, Middaugh said.