The present invention provides compositions and methods for human neural
cell production. More particularly, the present invention provides
cellular differentiation methods employing amphiphilic lipid compounds,
preferably ceramide analogs of the .beta.-hydroxyalkylamine type and
optionally employing an essentially serum free MEDII conditioned medium
for the generation of human neural cells from pluripotent human cells.
The methods alternatively comprise modulating apoptosis by modifying the
levels of PAR-4, with or without the presence of amphiphilic lipid
compounds and optionally employing MEDII conditioned medium. The methods
alternatively encompass modulating apoptosis by modulating the
intracellular concentration of endogenous lipid second messengers, such
as ceramide.