Stem cell study paves way for patient therapies: expert

Stem cells that have been specifically developed for use as clinical therapies are fit for use in patients, suggests an independent study of their genetic make-up published on Thursday.

The research, which focused on human embryonic stem cells, paves the way for clinical trials of cell therapies to treat conditions such as Parkinson's disease, age-related degeneration of the eyes and spinal cord injury, said a press release from the University of Edinburgh.

The study also sets out a cost-effective approach for monitoring the quality of stem cell-based products and newly emerging cell therapies.

Stem cells have the potential to become any of the varied cell types found in the body. Researchers have been investigating how they may be used to repair or replace damaged tissues in patients.

However, because the cells continuously produce copies of themselves, there are concerns that they may acquire genetic abnormalities that could lead to cancer.

Scientists at the University of Edinburgh investigated the genetic make-up of human stem cells that have been grown in the laboratory from cells found in the early embryo.

The 25 cell lines tested were all "clinical-grade", which means they meet the strict quality requirements for cell lines earmarked for use as therapies.

The team at the Medical Research Council Centre for Regenerative Medicine analyzed each of the cell lines using a technique called molecular karyotyping, which is a highly sensitive method of detecting genetic abnormalities.

More than half of the cell lines carried large but stable genetic differences, the researchers found. However, these changes are also present in healthy people without significant consequences, reflecting the genetic diversity of the human population.

They found that a small number of the cell lines acquired genetic problems if they were grown in the laboratory for too long. Researchers say this highlights the need for continued genetic testing of emerging stem cell-based products to ensure they are suitable for use in patients.

More than three-quarters of the global clinical-grade embryonic stem cell lines have been established in Britain. The stem cell lines analyzed in the study were established for clinical use by the Universities of Sheffield and Manchester, King's College London, and Roslin Cells, a company that specializes in the production of clinical-grade cells for use in therapies.

Tilo Kunath, Senior Research Fellow at the Medical Research Council Center for Regenerative Medicine, University of Edinburgh, said:" This is the largest study of therapeutically useful stem cells to date and shows that we are in a good place to push forward new cell therapies into clinical trials."

The study is published in the journal Scientific Reports. Endit