Differentiation of Mouse Embryonic Stem Cells into Dorsal Interneurons of the Spinal Cord Using BMP4 and Activin A

Objective: in vertebrates, bone morphogenetic proteins (bmps) and activin signals playmultiple roles in dorso-ventral patterning and development of the spinal cord. here theinductions of bmp 4 and activin a on embryonic stem cells (escs) into dorsal interneuronshave been studied.materials and methods: four different treatments have been used for mesc derivedneural precursors; they include bmp4 (1ng/ml and 10ng/ml), activin a (100 ng/ml), andactivin a+bmp4 (100ng/ml, 10ng/ml). induction’s effect on expression of specific dorsalinterneuron markers in mature neurons have been evaluated by the use of immunocytochemistryand rt-pcr.results: treatment of esc-derived neural precursors with bmp4, activin a, or bothshowed an increased generation of both di1 and di3 interneurons (lhx2 and isl-1-positivecells) compared to the control group. however, the synergistic effect in generation of di3was not observed when both factors were used. moreover, rt-pcr analysis of differentiatedcells showed the expression of lhx9, lhx1, and isl1, the transcription factors that aremarkers of di1, di2, and di3 interneurons respectively.conclusion: our results showed that specific combination of developmental signalingmolecules can direct the differentiation of escs into dorsal interneurons. furthermore,qualitative and quantitative differences in signaling by different members ofthe tgf-â superfamily may play a role in the specification of different types of dorsalinterneurons.