Caterpillars produce flu vaccine

Flu vaccine is normally made using chicken eggs but now for the first time research has shown that genetically engineered flu vaccine can be made from yellow striped caterpillars according to a University of Rochester study.

Early results suggest that this caterpillar method could be a faster, easier alternative to traditional egg-based production. If this proves to be the case when scaled up then this might provide a quicker vaccine development cycle in response to a pandemic.

The research was funded by the vaccine's maker, Protein Sciences Corp. The company designed the study with Dr. John Treanor, director of UR's Vaccine Treatment and Evaluation Unit and lead author of the study. Dr.Treanor, is also professor of medicine and of microbiology and immunology at UR.

The results are reported in the Journal of the American Medical Association.

The experimental vaccine used in the research was designed to protect against three of the common influenza strains. Among participants who got single high-dose injections, none developed the flu and at least two-thirds had a strong immune response.

More than half of those given a lower dose had a strong immune response, and two got flu.

In a control seven patients who received a dummy vaccine got the flu.

451 adults took part in the study during the 2004-05 flu season.

Current production methods takes about nine months to produce vaccine supplies and rely on hens laying millions of eggs. Live flu viruses are injected into the eggs and multiply, then the shells are broken and the viruses inactivated and treated to create vaccine.

The experimental method uses fall army worms — abundant caterpillars that are vulnerable to a caterpillar virus. The researchers replaced a gene from that virus with a flu virus gene, then injected it into the worms to make more flu viruses. The process took about a month less than the egg method and didn't involve using live flu viruses.

The study is likely to boost interest in insect production methods as an alternative to traditional egg based methods for producing flu vaccine.