The long projections that stretch out from the dendritic cell give it its name, one derived from the Greek word for "treelike." The job of the dendritic cell is that of an educator. This elite member of the human immune system grabs a piece of a foreign invader (an antigen)--whether from a virus, bacterium or another organism--and sends out an alarm. It waves a piece of antigen that acts as a signal so that T cells can rush in and dispatch the interloper.
In principle, the actions of the dendritic cell suggest a wholly new approach to cancer therapeutics, except for one hitch. In the terminology of immunologists, cancer cells are "self"--not encroaching outsiders. A late-stage clinical trial of a cancer vaccine using dendritic cells may be completed by next year and may prove whether or not such a drug can overcome self.
This article was originally published with the title Overcoming Self.