Intracerebral cell therapy, which aims to substitute striatal neurons lost to Huntington's disease by striatal neuroblasts and neural precursors obtained from embryos after elective abortion, has proven beneficial in patients with the disease. Theoretical projection models suggest that the clinical effects of grafting will lead to an initial improvement followed by a period of secondary decline due to the ongoing disease process. However, follow-up has not been long enough to assess the duration of clinical benefit of the treatment up to now.
Anne-Catherine Bachoud-Lvi (Henri Mondor Hospital, France) and colleagues have previously shown, in a pilot study, that intracerebral neural grafts lead to motor and cognitive improvement in patients with Huntington's disease 2 years after the procedure. In their current article, they present data for five patients from their pilot study, assessed annually for up to 6 years after neural grafting.
The procedure provided long-term clinical benefits to three patients in parallel with long-lasting focal improvement in brain metabolic activity. Progression of the disease led to heterogeneous secondary clinical alterations and changes of cerebral metabolism.
Whereas neuronal transplantation is not a permanent cure for Huntington's disease, it does provide a period of improvement and stability. Although neuroprotective treatment seems to be unavoidable in the disease, improvement of the surgical procedure and in patient selection could improve the therapeutic value of neuronal transplantation. Bachoud-Lvi concludes: "Neuroprotection could stop the disease, but only a graft can restore lost function."