Abstract
Improvements in quality of life and life expectancy have been observed in amyotrophic lateral sclerosis (ALS) patients transplanted with CD133(+) stem cells into their frontal motor cortices. However, questions have emerged about the capacity of cells from these patients to engraft and differentiate into neurons. The objective of this work was to evaluate the in vitro capacity of CD133(+) stem cells from 13 ALS patients to differentiate into neuron lineage. Stem cells were obtained through leukapheresis and cultured in a control medium or a neuroinduction medium for 2-48 hours. Expression of neuronal genes was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical techniques. Fluorescence microscopy demonstrated that CD133(+) stem cells from ALS patients incubated for 48 hours in a neuroinduction medium increased the detection of neuronal proteins such as nestin, β-tubulin III, neuronal-specific enolase, and glial fibrillary acidic protein. RT-PCR assays demonstrated an increase in the expression of β-tubulin III, nestin, Olig2, Islet-1, Hb9, and Nkx6.1. No correlation was found between age, sex, or ALS functional scale and the CD133(+) stem cell response to the neuroinduction medium. We conclude that CD133(+) stem cells from ALS patients, like the stem cells of healthy subjects, are capable of differentiating into preneuron cells.