April 12, 2006

Scientists explore using bacteria and plants to produce vaccines

Biotechnology companies are searching for faster ways to mass-produce bird flu vaccines so as to replace the relatively slow egg-based system employed currently.

Turning bacteria, plants or insect cells into protein factories could be an alternative in the event of a flu pandemic, vaccine developers and US scientists said.

Vaccines constitute a key defense should the H5N1 avian flu virus that has spread among birds in Asia, Europe and parts of Africa mutate into a form easily transmitted among people.

Several companies are focusing on new ways for growing antigens needed to stimulate the immune system to fight an infection.

VaxInnate, a New Jersey-based biotechnology company, reported success using E. coli bacteria to produce vaccines. In addition, Dowpharma, a unit of Dow Chemical Co, has been working on bacteria found in soil and water which may churn out high volumes of antigens faster than E. coli.

Other companies are trying to make antigens in cells taken from insects and reproduced in a lab, or in plants. People could simply eat the plants, or the proteins produced could be extracted and put into vaccines.

A more viable option is growing the vaccine in cell cultures, a method large vaccine makers are working on.

Despite these breakthroughs, experts expect vaccines to be produced from eggs for years.