When cells grow out of control in the body, most people think of cancer, but this phenomenon also occurs in pulmonary arterial hypertension (PAH), a rare and deadly disease characterized by very high pressure in the arteries that supply blood to the lungs. New research co-led by Dr. Duncan Stewart may help explain why.

Dr. Stewart and his colleagues found that people with PAH have high levels of a protein called translationally controlled tumor protein (TCTP) in their plasma. Using laboratory models of PAH, they also showed that when certain blood vessel cells die, they transfer this protein to other cells in the lung via tiny particles called exosomes.

This causes the cells to replicate much more than normal. This research could lead to new therapies as well as a possible blood biomarker to track the progress of PAH in patients. See the American Journal of Respiratory Cell and Molecular Biology for details.