"The Chinese medical system makes money through transplant tourism, " says Nancy Scheper-Hughes of Organs Watch.

FORBES: Export Industry

But Dr Scheper and his colleagues found a new protein that becomes much more common in tumour cells when multidrug resistance appears.

ECONOMIST: Cell biology: The secret of the vaults | The

The circumstantial evidence is intriguing: as well as being more abundant in tumours than in ordinary cells, vaults, to Dr Scheper's eye, seem to congregate around the vesicles.

ECONOMIST: Cell biology: The secret of the vaults | The