Class ¢ó Betaª²Tubulin is expressed in human myoblasts and myotubes

    LIU Xia1, A Wernig2, JU Gong1

    1Institute of Neurosciences, Fourth Military Medical University, Xi¡¯an 710033, China, 2Department of Neurophysiology, University of Bonn, 53111 Bonn, Germany

    ¡¾Abstract¡¿ AIM: To determine whether pluripotent stem cells isolated from adult human muscle could be induced to differentiate into neural cells in vitro as a prelude to future skeletal muscle stem cells studies in therapy for nervous injury and diseases. METHODS: We employed neural induction medium which had been used in rats to induce human adherent myoblasts to differentiate into neural cells and investigated the expression of ¦Âª²Tubulin ¢ó, neurofilament and GFAP in human adherent myoblasts cultured by different medium by immunocytochemical, western blotting and RTª²PCR techniques. RESULTS: After differentiation of human adherent myoblasts by neural induction medium, no cells with a neural cell morphology (ie., small, refractile cell body with dendritic cell extensions) were seen. All remaining myoblasts cultured with neural induction medium, myoblasts with proliferation medium and myotubes with differentiation medium containing 20 mL/L HS were positive for ¦Âª²Tubulin ¢ó. C2C12 myoblasts were negative for ¦Âª²Tubulin ¢ó. In contrast, all the above cells were negative for the markers Neurofilament Mr 68¡Á103 and GFAP. Human myoblasts and myotubes positive for ¦Âª²Tubulin ¢óª²immunoreactivity were verified with RTª²PCR and western blotting techniques. CONCLUSION: We failed in inducing adult human adherent myoblasts to differentiate into neurons or glial cells. Human myoblasts and myotubes express neuron marker ¦Âª²Tubulin ¢ó but not neurofilament Mr 68¡Á103. The expression of ¦Âª²Tubulin ¢ó is not consistent with that of neurofilament Mr 68¡Á103 in human myoblasts. Thus, we question the justification of using ¦Âª²Tubulin ¢ó expression as a specific neuron marker for transdifferentiation studies. ......