T Cell ‘Traffic Control’ Boosts Drug Hope

U.S. scientists have begun to clarify how one of the body’s molecules controls the trafficking of T cells through the blood to fight infection.

The traffic control system — composed of a fat-like compound called S1P and its receptor on T cells — usually prevents T cells from launching harmful reactions. But when the S1P traffic cop reacts incorrectly, T cells can swamp healthy tissue.

The new research explains how a promising experimental drug treats the autoimmune disease multiple sclerosis by blocking excess S1P action, said Dr. Edward Goetzl of the University of California at San Francisco and Dr. Hugh Rosen, of the Scripps Research Institute.

The research shows the promise of similar strategies to prevent rejection of transplanted organs and tissues without compromising essential immune defenses, according to the study published in a special issue of Nature Reviews Immunology.