ReNeuron, which develops neural stem cell lines marketed by Millipore, has published a new protocol that ensures that one of those cell lines differentiates into “electrophysiologically functional” dopaminergic neurons that better mimic the behavior of neurons in vivo.
The protocol, published in this week’s issue of BMC Neuroscience, is called “pre-aggregation differentiation” and generates electrophysiological activity in the company’s ReNcell VM line. The cell line is derived from the ventral mesencephalon region of the brain, but not in its ReNcell CX line, which is derived from the cortex.
Both cell lines are exclusively marketed by Millipore under an agreement that ReNeuron signed with Serologicals’ Chemicon subsidiary last April. Millipore acquired Serologicals in July and formally launched the ReNcell product line in November [CBA News 11-17-06].
The findings “further indicate the ReNcell VM cell line could be a very useful tool in the research to understand neurobiology and to develop therapeutic solutions to conditions known to involve dopaminergic neurons such as Parkinson's disease,” Michelle Greene, director of marketing in Millipore’s Bioscience division, wrote in an e-mail to CBA News.
John Sinden, chief scientific officer of ReNeuron, told CBA News that the study results are important because they indicate that the ReNCell VM neurons “genuinely function” — a characteristic that wasn’t known prior to the study.
Sinden said that ReNeuron is currently discussing with Millipore an off-the-shelf “differentiation assay kit” based on the protocol described in the study that would enable researchers to generate fully functional neurons in 24 hours. In the meantime, he said, researchers are free to follow the methods described in the paper, though that is likely to be a time-consuming task.
Millipore’s Greene declined to comment on the discussions, noting that the company does not discuss activities that are under development.
She did note that the ReNcell products form a “vital part” of Millipore’s broader neurobiology offering, which includes rat neural stem cells, media for expanding and freezing them, kits for differentiating them into neurons and astrocytes, and kits to characterize the extent of differentiation.
Sinden noted that the ReNcell cell lines are well-suited to high-throughput assays, and that ReNeuron has already used them in-house with 96-well plates.
According to the BMC Neuroscience paper, only two previous differentiation studies on human neural stem cells successfully demonstrated true electrophysiological function, in which the neurons exhibited action potential, which is an electrical current that travels down an axon of the neuron.
The goal of the ReNeuron scientists, in collaboration with researchers from University College London, was to develop a protocol that would differentiate the stem cells into functional neurons and ensure that they remain viable in culture indefinitely. They overcame this challenge by immortalizing the cells with the myc oncogene.
The findings “further indicate the ReNcell VM cell line could be a very useful tool in the research to understand neurobiology and to develop therapeutic solutions to conditions known to involve dopaminergic neurons such as Parkinson's disease.”
Sinden said that the ReNcell lines are easier to handle and generate more reproducible results than primary neurons. In addition, he said, researchers can go “from early-stage screening to late-stage screening on the same cells … which makes comparability between experiments a lot easier.”
ReNeuron is seeing “more enthusiasm” recently from pharmaceutical companies regarding the use of stem cells for drug screening, Sinden said. One reason, he said, is “that there are more products available that are now getting validation from academic studies, so they can sort of see what it is they’re buying in advance.”
ReNeuron’s primary business is developing stem-cell therapies, and the company submitted an investigational new drug application with the US Food and Drug Administration at the end of last year for a stem-cell therapy for stroke-related disability.
However, all of the company’s revenues so far come from its ReNcell partnership with Millipore. In the six months ending Sept. 30, 2006, the last period for which its financial results are available, the company generated £42,000 ($83,000) from the distribution deal, compared to zero revenues in the prior-year period.
The company posted a net loss of £3.2 million for the period, an improvement over £4.3 million for the same period in 2005.
ReNeuron said in its interim report for the period that the sale of the ReNcell products for non-therapeutic applications “will provide early commercial validation of our technologies and bring ReNeuron a near-term revenue stream.”
The company said in the report that it is also developing the ReNcell HEP hepatocyte cell line, “which has high potential utility as a drug toxicology testing and screening tool.”
ReNeuron said in the report that it had recently signed a collaboration with Japanese tissue-engineering firm CellSeed to develop “novel, liver cell culture systems using the ReNcell HEP cell line in conjunction with CellSeed’s temperature-sensitive polymer technology.”
Sinden said ReNeuron is using the same technology to develop cell lines for pancreatic and other cell types.
ReNeuron was founded in 1997 to commercialize technology developed at the Institute of Psychiatry at Kings College London. The company, based in Guildford, UK, currently employs around 25 people and is traded on the London Stock Exchange under the ticker symbol RENE.