I did a brief email Q&A interview with Dr. Bob Lanza of Advanced Cell Technology (ACT) on their new hES-MSC pre-clinical data for Multiple Sclerosis. I discussed the paper itself in a concise review yesterday here.
Thanks to Dr. Lanza for doing the interview.
1. Were you surprised at the fact that the therapeutic benefit did not require engraftment or even the use of proliferative hES-MSCs?
No, not at all. MSCs usually persist for only a few days or weeks, and exert their therapeutic effects during that short time period
2. Any thought on the mechanism by which the hES-MSCs are beneficial? Trophic factors?
MSCs have myriad functions. They can, of course, modulate B and T cell function and impact the autoimmune process itself. But extravasation also seems to be very important, so release of trophic factors at the local site of inflammation and damage may also be a critical part of the mechanism by which they are beneficial.
3. Why inject intraperitoneally? Have you done any studies based on IV injection or direct transplantation into the CNS itself?
The cells have homing receptors and migrate to the site of injury regardless of the route of administration. Although we haven’t looked at it in this particular model, IV works quite well in the other autoimmune models we’ve examined. I suspect direct transplantation into the CNS itself would work equally well, if not better. However, that would obviously be a less desirable route for clinical application.
4. What are the steps between where these studies stand today and getting a therapy based on this product into clinical trials?
We need to complete IND enabling studies—i.e. dosage, safety, tumorigenicity, and biodistribution studies etc.