Man-made thymus churns out immune cells

In the thymus, so-called T cells mature into full-fledged immune system sentinels. Seeking better ways to grow these white blood cells in the laboratory, David T. Scadden of Massachusetts General Hospital in Boston and his colleagues have built an artificial thymus by seeding a three-dimensional carbon matrix with tissue from the immune organ.

When precursor T cells are added to this matrix, mature cells emerge within 2 weeks, the investigators report in the July Nature Biotechnology. This artificial thymus “has the potential to generate not only normal T cells to replace cells lost as a result of infection, chemotherapy, radiotherapy or aging, but also cells that can be manipulated to treat a number of diseases,” David L. Porter and Stephen G. Emerson, both of the University of Pennsylvania in Philadelphia, say in an accompanying commentary.