Background aims: Amyotrophic lateral sclerosis (ALS) is characterized by the selective death of motor neurons. CD133 + stem cells are known to have the capacity to differentiate into neural lineages. Stem cells may provide an alternative treatment for ALS and other neurodegenerative diseases. Methods: Five men and five women (aged 38-62 years) with confirmed ALS were included in this study. Our institutional ethics and research committees approved the protocol. After informed consent was obtained, patients underwent Hidrogen-Magnetic Resonance Imaging (H-MRI) spectroscopy and were given scores according to an ALS functional rating scale, Medical Research Council power muscle scale and daily living activities. Bone marrow was stimulated with 300 ¿g filgrastim subcutaneously daily for 3 days. Peripheral blood mononuclear cells were obtained after admission by leukapheresis. The cell suspension was conjugated with anti-human CD133 superparamagnetic microbeads, and linked cells were isolated in a magnetic field. The isolated cells (2.5-7.5 × 10 5 ) were resuspended in 300 ¿L of the patient's cerebrospinal fluid, and implanted in motor cortexes using a Hamilton syringe. Ten patients with confirmed ALS without transplantation were used as a control group. Patients were followed up for a period of 1 year. Results: The autologous transplantation of CD133 + stem cells into the frontal motor cortex is a safe and well-tolerated procedure in ALS patients. The survival of treated patients was statistically higher (P=0.01) than untreated control patients. Conclusions: Stem-cell transplantation in the motor cortex delays ALS progression and improves quality of life.