July 15, 2005

MICROBIOLOGY
Bacterium Proves Essential to Immune System Development
The bacteria living in our digestive tract are known to help digestion and intestinal function, but a new study suggests that one common intestinal bacterium may do even more. In the July 15 Cell, a team led by Dennis Kasper (on left) and Sarkis Mazmanian reports that Bacteroides fragilis contributes to the immune system’s development. The team has identified a specific molecule on the bacterium’s outer coat that promotes proper immune function in mice—the first known “symbiosis factor” responsible for carrying out a beneficial relationship between mammals and bacteria.

ONCOLOGY: Smart Cancer Drug Passes Test Against Multiple Myeloma
A paper in the June 16 New England Journal of Medicine reports that a new kind of cancer drug is twice as good at treating an incurable blood cancer as a conventional medication. To people with myeloma and their doctors, the study broadens access to a potentially more effective therapy. To other cancer researchers, the findings confirm the tangible benefits that can result from a molecular understanding of how drugs work against disease. To the team headed by Kenneth Anderson that contributed much of the preclinical and clinical testing, the results are the vanguard of scores of other novel agents under scrutiny in the lab and clinic.

ENDOCRINOLOGY: Molecular Middleman Puts Thyroid Hormone in Developmental Signaling Pathway
The active form of thyroid hormone, T3, is regulated by a delicate feedback mechanism so its level in the bloodstream rarely fluctuates. Yet T3 levels can vary wildly within cells. Antonio Bianco and his colleagues have identified a molecule, WSB1, that helps regulate how much active thyroid hormone is produced inside cells. In the June 19 online Nature Cell Biology, they report that WSB1-controlled thyroid hormone activation plays a role not just in homeostasis, but also in a critical developmental pathway.