US and Japanese researchers have converted white blood cells (WBC) into stem cells. A study published in this month's Cell Stem Cell showed how researchers successfully infected WBCs with a virus containing the four genes needed to reprogram them into iPS (induced pluripotent stem) cells.
WBCs are easily obtained from blood, but producing patient-specific stem cells has previously required invasive skin biopsies or the difficult and expensive isolation of specialised immune cells.
Dr Judith Staerk, one of the lead researchers from the Whitehead Institute, Massachusetts, said: 'Blood is the easiest, most accessible source of cells, because you'd rather have 20ml of blood drawn than have a punch biopsy taken to get skin cells'. The iPS cells were produced from frozen blood samples, which shows this approach could be used on blood already stored in blood banks.
Professor Rudolf Jaenisch, head of the study said: 'There are enormous resources - blood banks with samples from patients - that may hold the only viable cells from patients who may not be alive anymore or from the early stage of their diseases'.
The researchers at the Whitehead Institute are interested in using this approach to study blood diseases. Professor Jaenisch, said 'If the patient had a neurodegenerative disease, you can use the iPS cells to study that disease'.
'You could reprogram blood samples from patients where the underlying cause of their diseases is not known, and get cell numbers large enough to screen for genetic factors and study the molecular mechanisms underlying the blood disorders'.
Dr Shinya Yamanaka, another researcher involved with the project said these studies 'represent a huge and important progression in the field'.