The trial you linked (as well as the two other registered trials using mesenchymal stem cells for Ankylosing Spondylitis that I found) are using allogeneic (donor) MSCs. I've been in MSC research/development for 17 years and now cryopreserve them as a service (Forever Labs YCS17). From my experience and knowledge of clinical efforts, allogeneic is limited by immuno-rejection of the MSCs after a few days. That's not to say that they can't provide benefit, but just that their window of action is limited as your body recognizes the donor cells as foreign, and weeds them out (perhaps in AS this is enough). The allogeneic issue is actually why I started banking them. I wanted my own young MSCs available to me later in life.

I'd be curious if you can get the clinic in China to expand your own MSCs. I did some MSC research in Beijing long ago. IMO they are ahead of us in many respects, but they also push the envelope more, and you need to be cautious. That goes for everywhere, actually. Just for different reasons.