Canadian researchers have succeeded in producing a tobacco plant that contains a human gene that expresses the cytokine interleukin 10, a drug used to prevent rejection of transplanted organs. The British Medical Journal reports that researchers hope to produce enough interleukin 10 cheaply enough to be able to make an oral anti-inflammatory vaccine for bowel diseases and certain autoimmune diseases.

• The first plants containing the gene were grown in a laboratory, and the first field tests in Canada of a plant bearing a human gene will be conducted soon, according to Anthony Jevnikar, the leader of the project.

• Cytokines, which are biological response modifiers, are too expensive to manufacture synthetically for the type of oral treatment envisioned.

• Jevnikar's group had previously developed an oral vaccine for protection against autoimmune diseases, and the current project originated from that work.

• In the earlier work, they fed plants containing a different protein (not interleukin 10) to mice that were prone to developing diabetes; feeding the mice these plants seemed to protect them from the disease.

The tobacco plant is considered to be especially useful in producing interleukin 10 because it is not a food crop, it can be segregated from other plants, and it dies during the winter, thus allaying concerns that the engineered genes could spread to other plants.

Source: David Spurgeon, "Tobacco could be used to produce interleukin 10," British Medical Journal, July 17, 1999.

For text http://www.bmj.com/cgi/content/full/319/7203/143/a