OBJECTIVETo investigate methods of promoting revascularization of tracheal transplantation to increase the length of graft.

METHODSTransfer recombinant plasmid pcDNA3.1/myc-His(-)C-bFGF and pCD(2)-VEGF(121) into rabbit cervical muscle by direct injection of plasmid following electric pulses in vivo. Use histochemistry and immunohistochemistry analysis of muscles injected to show the transferred gene expression and the biological effect. Based on the former experiment, conduct gene therapy to the rabbit tracheal autotransplantation wrapped by cervical combined muscles by injecting plasmid DNA directly, combined with gene sutures following electric pulses. Observe and analyze the effect on trachea viability.

RESULTSThe recombinant plasmid, pcDNA3.1/myc-His(-)C-bFGF and pCD(2)-VEGF(121) was transferred into muscles flap in vivo successfully. The active protein bFGF and VEGF(121) were expressed at high levels. Blood vessels increased significantly in the muscles, and blood circulation was improved by local angiogenesis. Ten rings tracheal autograft wrapped by transgenic muscles integrating with gene structure revascularized completely, and the rabbit survived for a long period of time. There was significant difference between gene therapy group and control group (P < 0.01). There was no significant difference between bFGF gene therapy group and VEGF(121) gene therapy group. Almost rabbits in the control group died of graft necrosis.

CONCLUSIONTracheal grafts revascularization can be established early by the cervical combined muscles flap wrapping associated with single gene therapy. The length of the tracheal can be increased simultaneously.