Bacteria offer drug for organ recipients. (Biomedicine).

Korean investigators have identified a compound that suppresses the immune system of animals. They suggest it may offer an alternative to similar drugs currently used by people receiving organ transplants.

A research group led by Jae-Hyuck Shim of Yonsei University in Korea isolated the new compound, called tautomycetin, from a bacterial strain that grows in the soil of Cheju, an island about 40 miles south of the Korean peninsula. The microbes apparently secrete tautomycetin in self-defense: The compound can kill fungi and other bacteria that may prey on the Cheju strain.

In an upcoming Proceedings of the National Academy of Sciences, the research team reports that tautomycetin also kills human immune cells called T cells in lab dishes. The researchers tried the compound on mice receiving heart transplants, with the idea of preventing rejection of the organs.

Untreated mice typically reject a transplanted heart and die within 2 weeks. In contrast, tautomycetin-treated mice survived an average of 160 days after receiving a transplant. Shims group says that survival time is even longer than that of heart-transplant mice treated with cyclosporin A, a drug often used in people receiving organ transplants.--J.T.