Nanoemulsion vaccines show increasing promise

Oil-based nasal vaccine technique produces immunity against smallpox, HIV

High energy oil-in-water emulsions used in the U-M vaccines are made up of droplets 200 nanometers in size. Click here for more information.

ANN ARBOR, Mich. — A novel technique for vaccinating against a variety of infectious diseases – using an oil-based emulsion placed in the nose, rather than needles – has proved able to produce a strong immune response against smallpox and HIV in two new studies.

The results build on previous success in animal studies with a nasal nanoemulsion vaccine for influenza, reported by University of Michigan researchers in 2003.

Nanoemulsion vaccines developed at the Michigan Nanotechnology Institute for Medicine and the Biological Sciences at U-M are based on a mixture of soybean oil, alcohol, water and detergents emulsified into ultra-small particles smaller than 400 nanometers wide, or 1/200th the width of a human hair. These are combined with part or all of the disease-causing microbe to trigger the body’s immune response.

A team led by U-M scientist James Baker Jr., M.D., the institute’s director, pioneered the technology, for which a patent was recently awarded to U-M.

“The two studies show the nanoemulsion platform is capable of developing vaccines from very diverse materials. We used whole virus in the smallpox vaccine. In the HIV vaccine, we used a single protein. We were able to promote an immune response using either source,” says Baker.

The technology is licensed to NanoBio Corp., an Ann Arbor-based biotech company which Baker founded in 2000 and in which he has a financial interest. Baker is the Ruth Dow Doan Professor of internal medicine and Allergy Division chief at the U-M Medical School.

The surface tension of the nanoparticles disrupts membranes and destroys microbes but does not harm most human cells due to their location within body tissues. Nanoemulsion vaccines are highly effective at penetrating the mucous membranes in the nose and initiating strong and protective types of immune response, Baker says. U-M researchers are also exploring nasal nanoemulsion vaccines to protect against bioterrorism agents and hepatitis B.

Potential for a better smallpox vaccine

The smallpox results, which appear in the February issue of Clinical Vaccine Immunology, could lead to an effective human vaccine against smallpox that is safer than the present live-vaccinia virus vaccine because it would use nanoemulsion-killed vaccinia virus, says Baker.