Adenovirus-mediated transmission of a dominant negative transforming growth factor-beta receptor inhibits in vitro XXXX cranial suture fusion.

@entity641 @entity281 @entity19 @entity778
Recent studies have implicated the transforming growth factor (TGF)-beta family in the regulation of pathological sporadic cranial suture fusion. In addition, these studies have shown that @entity641 is highly expressed by the dura mater underlying fusing @entity19 cranial sutures. The purpose of the present experiments was to analyze the effects of disrupting @entity641 signaling during programmed @entity19 cranial suture fusion. Using recombinant DNA technology, a replication-deficient adenovirus encoding a defective @entity641 receptor (Ad.DN-TbetaRII) capable of blocking @entity641 biological activity was constructed. @entity19 posterior frontal sutures were harvested before the initiation of suture fusion (postnatal day 25), and the dura mater underlying the suture was infected with vehicle, Ad.DN-TbetaRII, or control virus (Ad.LacZ; n = 10 each). Sutures were cultured for 14 or 30 days in an organ culture system and analyzed macroscopically and histologically.X-gal staining of Ad.LacZ-infected sutures 14 days after culture revealed strong staining of cells localized to the dura mater. Macroscopic analysis revealed complete sutural fusion in vehicle and Ad.LacZ-infected sutures. In contrast, Ad.DN-TBRII-infected sutures demonstrated nearly complete patency. Histological analysis confirmed our macroscopic observations with sutural fusion in 81.3 +/- 10 percent and 74.5 +/- 9 percent of vehicle and Ad.LacZ-infected sutures, respectively, versus 38.1 +/- 12 percent (p < 0.001) in Ad. @entity281 sutures. In addition, transfection with the Ad. @entity778 resulted in a significant attenuation of anterior-to-posterior suture fusion, with the majority of fused sections localized to anterior sections. These data strongly implicate @entity641 biological activity in the dura mater underlying the posterior frontal suture in the regulation of programmed sutural fusion. In addition, this study demonstrates the utility of adenovirus-mediated gene transfer in preventing programmed sutural fusion.
