Ventrally emigrating neural tube cells differentiate into vascular smooth muscle cells

A multipotential cell population originating in the ventral part of the hin dbrain neural tube, the ventrally emigrating neural tube cells (VENT cells) , has recently been shown to migrate into the craniofacial mesenchyme. Beca use vascular smooth muscle cells develop from this mesenchyme, we sought to determine if the VENT cells contributed to their differentiation. VENT cel ls were tagged with replication-deficient retroviral vector with LacZ by mi croinjection into the lumen of the rostral hindbrain of chick embryos on da y 2. Embryos were processed for the detection of LacZ positive cells on day 7. LacZ-positive cells were present in the wall of craniofacial arteries a nd veins. Immunostaining with the smooth muscle ol.-actin confirmed the lab eled cells to be smooth muscle cells. It is concluded that some vascular sm ooth muscle I-ells differentiate from neural tube cells, the developmental and functional significance of which remains to be established. (C) 1999 El sevier Science Inc. All rights reserved.