Washington, July 29 - Researchers have found a way to directly convert spermatogonial stem cells, precursors of sperm cells, into tissues of the prostate, skin and uterus.

Their approach may prove to be an effective alternative to the medical use of embryonic stem cells.

The hunt for alternatives to embryonic stem cells has led to some promising yet problematic approaches, some of which involve spermatogonial stem cells (SSCs).

Researchers recently observed, for example, that lab-grown SSCs will eventually give rise to a few cells that look and act like embryonic stem cells.

This process can take months, however, and only a small percentage of the SSCs are converted into 'embryonic stem (ES)-like' cells.

The new method, recently developed at the University of Illinois (U-I), takes advantage of the unusual interaction of two tissue types: the epithelium and the mesenchyme.