Regenerative medicine: Cell reprogramming gets direct.

The article reports on the conversion of one type of differentiated cell into another distinct type without going through an intermediate stem-cell stage. It mentions that the ability to reprogram fibroblasts to embryonic-like stem cells was a remarkable success which cleared the way to create disease- and patient-specific stem cells. The indirect routes involve reprogramming of a variety of adult cell types from different lineages to produce a de-differentiated embryonic stem (ES) cell state. Scientists show that a direct route can be taken by inducing lineage-specific transcription factors encoded by genes, increasing the efficiency of conversion. Further, it questions how many different cell types can now be generated by activating distinct combinations of lineage-specific factors.