Huntington’s disease (HD) is a hereditary, fatal neuropsychiatric disease. HD occurs in one in every ten thousand people in the USA. The effects of the disease on patients, families, and care givers are devastating as it reaches from generation to generation. This fatal disease touches all races and socioeconomic levels, and current treatment is strictly palliative. Existing drugs can reduce the involuntary movements and psychiatric symptoms, but do nothing to slow the inexorable progression. There is currently no cure for HD. People at risk of inheriting HD can undergo a genetic counseling and testing to learn if they are destined to develop this dreadful disease. Many people from HD families fear the consequences of stigma and genetic discrimination. Those at-risk often do not choose to be tested since there are currently no early prevention strategies or effective treatments.
We propose a novel therapy to treat HD: implantation of cells engineered to secrete Brain-Derived
Neurotrophic Factor (BDNF), a factor that can promote addition of new neurons to the affected area of the brain. BDNF is reduced in HD patients due to interference by the mutant Huntingtin (htt) protein that is the hallmark of the disease. We have discovered that mesenchymal stem/stromal cells (MSC), a type of adult stem cell, are remarkably effective delivery vehicles, moving robustly through the tissue and infusing therapeutic molecules into damaged cells they contact. In animal models of HD implantation of MSC into the brain has significant neurorestorative effects and is safe. We propose to use these MSCs as “nature’s own paramedic system”, arming them with BDNF to enhance the health of at-risk neurons. Our HD animal models will allow the therapy to be carefully tested in preparation for a proposed Phase I clinical trial of MSC/BDNF implantation into the brain of HD patients (HD-CELL), with the goal of slowing disease progression.
Delivery of BDNF by MSC into the brains of HD mice is safe and has resulted in a significant reduction in their behavioral deficits, nearly back to normal levels. We are doing further efficacy and safety studies in preparation for the Phase I clinical trial. The significance of our studies is very high because there are currently no other options, there is no current treatment to delay the onset or slow the progression of the disease.. There are potential applications beyond Huntington’s disease. Our biological delivery system for BDNF sets the precedent for adult stem cell therapy in the brain and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinocerebellar ataxia (SCA), Alzheimer’s disease, and some forms of Parkinson’s disease. Since HD patients unfortunately have few other options, the potential benefit to risk ratio for the planned trial is very high.
In the first year of our grant we have successfully engineered human MSCs to produce BDNF, and are studying effects on disease progression in HD mice. We have developed methods to produce these cells in large quantities to be used for future human clinical studies. As we go forward in year 2 we plan to complete the animal studies that will allow us to apply for regulatory approval to go forward with the planned Phase I trial.
We have designed an observational study, PRE-CELL, to track disease progression and generate useful data in preparation for this future planned Phase I clinical trial. PRE-CELL has been approved by the institution’s ethics board and is currently enrolling subjects. PRE-CELL was designed to operate concurrently with the ongoing pre-clinical safety testing. For additional information go to: ClinicalTrials.gov Identifier: NCT01937923