Medial Ganglionic Eminence Cells Freshly Obtained or Expanded as Neurospheres Show Distinct Cellular and Molecular Properties in Reducing Epileptic Seizures.

AIMS: Medial ganglionic eminence (MGE) progenitors give rise to inhibitory interneurons and may serve as an alternative cell source for large-scale cell transplantation for epilepsy after in vitro expansion. We investigated whether modifications in the culture medium of MGE neurospheres affect neuronal differentiation and expression of MGE-specific genes. In vivo, we compared anticonvulsant effects and cell differentiation pattern among neurospheres grown in different culture media and compared them with freshly harvested MGE cells. METHODS: We used four variations of cell culture: standard, containing growth factors (EGF/FGF-2) (GF); addition of retinoic acid (GF-RA); withdrawal of EGF/FGF-2 (WD); and addition of retinoic acid and withdrawal of EGF/FGF-2 (WD-RA). Based on in vitro results neurosphere-grown (WD-RA or GF conditions) or fresh MGE cells were transplanted into the hippocampus. RESULTS: In vitro WD-RA showed increased neuronal population and higher expression of Dlx1, Nkx2.1, and Lhx6 genes in comparison with GF culture condition. After transplantation, fresh MGE cells and neurospheres (GF) showed anticonvulsant effects. However, fresh MGE cells differentiated preferentially into inhibitory neurons, while GF gave rise to glial cells. CONCLUSION: We conclude that freshly isolated and neurosphere-grown MGE cells reduced seizures by different mechanisms (inhibitory interneurons vs. astrocytes). Fresh MGE cells appear more appropriate for cell therapies targeting inhibitory interneurons for conferring anticonvulsant outcomes.

Immunological aspects in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron death, leading to muscle atrophy, paralysis, and death usually within 3 to 5 years after diagnosis. Most cases are sporadic, with still undefined etiopathogenesis. Both the innate and adaptive immune systems are involved in ALS, with special participation of T lymphocytes and microglia. Inflammation plays a dual role in the disease, protective and T regulatory cell rich in the early stages and deleterious as disease progresses. Attempts to modulate immune/inflammatory system response are reported in the literature, and while beneficial effects are achieved in ALS animal models, results of most clinical trials have been disappointing. The impaired blood-brain barrier is an important feature in the pathogenesis of ALS and likely affects the immune system response. The present review describes the role of the immune system in ALS pathogenesis and the tight coupling of immunity and central nervous system barrier function.