IN VITRO DIFFERENTIATION OF HUMAN STEM CELLS INTO DOPAMINERGIC NEURONS
Zeinab M. Kamel, Menna Abdel-Dayem, Nagla M. Salama, Hala Gabr*, Dalia Ibrahim
Departments of Histology and Clinical pathology*, Faculty of medicine, Cairo University
Background: The inability of the neurons to regenerate has encouraged the scientists to search for a method to replace damaged or dead nerve cells. Parkinson’s disease (PD) is the most common neurodegenerative disorder, affecting 2% of individuals over age 65 and 4-5% over 85 years, and it is caused by the loss of dopaminergic (DA) neurons. There is no effective treatment for PD and the disease progression cannot be counteracted. Therefore, nerve cell replacement is an important therapeutic option for PD.Aim of work: The aim of this study was to explore the in-vitro ability of human adult mesenchymal stem cells (MSCs) derived from peripheral blood, after their mobilization from bone marrow, to differentiate into DA neurons.Subjects and Methods: This study included 10 healthy donors (8 males and 2 females) undergoing stem cell mobilization. They were subcutaneously injected with Filgrastim (Granulocyte-colony stimulating factor) in a single daily dose of 10 µg/kg for 5 days. Then collection of mononuclear cells (MNCs) by apheresis was done on the fifth day one hour after injection of the last dose. Total leucocytic counts were done before and after mobilization. Culture and separation of MSCs were done. Cell viability test was done after culture, and immunophenotyping of CD44 cells was done before and after culture. Differentiation of MSCs into neural lineage was done using nerve growth factor. This was followed by induction of DA neurons using ascorbic acid. Cultured specimens were immunostained for neurofilament (NF) and tyrosine hydroxylase (TH).Results: Colonies of MSCs were detected by the inverted microscope 3 days after culture and they increased markedly after 7 days. They were proved to be MSCs by CD44 positivity. The mean percentage of cells stained for NF and TH was 15.38% and 5.94% respectively.Conclusion: MSCs could be isolated from peripheral blood after their mobilization from bone marrow, expanded and differentiated into DA neurons. This may be of value in treating PD.