Research Home University of South Florida, Dr. Paul Sanberg In the last few years, our research group has begun to work with human umbilical cord blood stem cells. These cells have demonstrated the ability to mature into various types of cells, depending upon external conditions. Data suggest that these cells are able to differentiate into pre-neural cells, making repair of an injured or defective nervous system possible. Patients with Sanfilippo Syndrome are unable to break down heparan sulfate because they lack a specific enzyme. Much of the damage caused by this disease is associated with a buildup of heparan sulfate. We intend to transplant human umbilical cord blood stem cells into a mouse model of Sanfilippo type III B. We hope that the transplanted cells, which have the needed enzyme, will thrive and prevent heparan sulfate accumulation so that disease progress will be delayed or, optimally, stopped. In this first year, our emphasis has been on obtaining the Naglu mutant mice (a model of Sanfilippo type III B) and establishing a colony. Dr. Svitlana Garbuzova-Davis and Dr. Alison Willing in our group have successfully produced 28 breeder pairs and a sufficient number of homozygous mice (1 mo of age) to begin transplanting the umbilical cord blood stem cells into the brain. We are using various behavioral tests to determine whether the cells will prevent or delay the onset of motor and cognitive deficits and extend lifespan of these mice. In addition, we will also determine the enzyme characteristics of the umbilical cord blood in vitro. We believe this novel cell source has the potential to change the way we treat Sanfilippo as well as other developmental disorders, and may lead to new strategies for enzyme replacement therapy.