Jan 26, 2011 11:30 GMT  ·  By
Microscopic image of human embryonic stem cells in the new defined culture created by UCLA researchers
   Microscopic image of human embryonic stem cells in the new defined culture created by UCLA researchers

A group of stem cell biologists and bioengineers based at the University of California in Los Angeles (UCLA) were able to develop a new method for producing high-quality embryonic stem cells (ESC).

These cells are absolutely essential to the field of regenerative medicine, which seeks to treat a vast number of conditions using stem cell implants. But a number of obstacles exist in this field today.

For starters, it's very difficult to manufacture ESC batches that have a consistent quality. The variations currently being recorded are caused by the mediums in which these cell cultures are grown.

If these types of implants are ever to succeed widely, and be employed as standard practice, they need to rely on clinical-grade stem cells. Obtaining this cells is however proving to be problematic.

The mouse “feeder” cells and bovine serum mediums used to cultivate the ESC contaminate the cells, and cause each new batch to exhibit new, undesirable variations, the UCLA research team explains.

In their new experiments, the experts managed to discover an optimal combination and concentration of small molecules called inhibitors, that allow for the creation of ESC with consistent quality.

By using the new approach, the cells can also be maintained for prolonged periods of time in lab, without the need for using feeders and serums for the job. This was achieved via the implementation of a feedback system control (FSC) scheme in the process flow of obtaining and caring for these cells.

“What is significant about this work is that we've been able to very rapidly develop a chemically defined culture medium to replace serum and feeders for cultivating clinical-grade [ESC] cells, thereby removing a major roadblock in the area of regenerative medicine,” explains expert Chih-Ming Ho.

He holds an appointment as the Ben Rich–Lockheed Martin Professor at the UCLA Henry Samueli School of Engineering and Applied Science, and as a member of the National Academy of Engineering.

The researcher and his group published the full details of their major breakthrough in the January 25 issue of the esteemed scientific journal Nature Communications.

“Although other studies have demonstrated growth of [ESC] cells under defined media formulations and/or on defined surfaces, to the best of our knowledge, this is the first study that combines defined cultures with routine single-cell passaging, which plays an important role in supplying a large mass of clinically applicable cells,” explains expert Hideaki Tsutsui

“Thus, our [ESC] cell culture system, guided by the FSC technique, will bring [ESC] cells one step closer to clinical therapies,” adds the scientist, who was the lead author of the new study, and also a UCLA postdoctoral scholar.