人工血管のハイブリット化

人工血管により高度な機能をもたす目的で，ハイブリット化が今日進められるようになってきた。この背景について説明するとともに，我々の独自に行っているハイブリット型人工血管作成の方法およびその成果について報告する。その具体的方法としては以下の通りである。末梢静脈小片を勇刀にて細切したのち，約20ccの生理的食塩水に入れて静脈組織細切片浮遊液を作った。次に高有孔性人工血管の一端より吸引管を挿入し，これを作成した液に入れ，吸引によって組織片を外側から人工血管壁に絡ませた。次に新鮮な血液を注ぎ，組織片をさらに固着させた。成犬胸部下行大動脈へこのような処理をしたポリエステル布製人工血管を植え込んだところ，植え込み5日目に新生血管壁内部に無数の内皮細胞の増殖像がみられ，35日目の例では吻合部はもとより，人工血管の中央部ですら内皮細胞による完全な被覆を認めた。 　以上のような方法で新生血管壁が容易に形成されることが判明したことより，今後，他の人工臓器分野でもハイブリット化が予測される。

Recently, vascular grafts had contributed in the treatments of various vascular disease, and today, was required to have fine functions like native blood vessels. Many kinds of approaches to develop the ideal graft had been applied. In these efforts, endothelial cells seeding technique to fabric vascular prostheses was reported successfully, however, it was not for general use. To get and proliferate the endothelial cells, special techniques and facilities were required. Moreover, it was not available for emergency use, smce the cell culture needed a certain period of time. To overcome these problems, we developed a reliable method to make a hybrid vascular graft as follows. Tissue fragments suspension was prepared using a piece of peripheral vein. Highly porous fabric vascular prosthesis was immersed into the suspension fluid. The tissue fragments were trapped from the outer surface of the prosthesis by intraluminal suction. Preclotting procedure was adopted to immobilize the tissue fragments to the fabric of the prosthesis. The prostheses were implanted into the thoracic descending aortae of 15 dogs. There was no bleeding at the time of the implantation. Numerous endothelial cells proliferation was observed in the specimen for 5 days after implantation. The surface was covered with thin layer of fibrin. Full endothelialization was noticed in the specimens of 35 days. The graft wall was completely healed. This method was very simple and easy to prepare, but the efficacy to promote the healing of the neointima was excellent.