Silk fibroin vascular graft: a promising tissue-engineered scaffold material for abdominal venous system replacement

Sho Kiritani,Takashi Tanaka,Daisuke Ito,Kiyoshi Hasegawa,Takuya Iida,Ryo Tanaka,Nobuhisa Akamatsu,Junichi Kaneko,Masaaki Morito,Takeaki Ishizawa,Mariko Tanaka,Junichi Arita,Tetsuo Asakura

doi:10.1038/s41598-020-78020-y

Sho Kiritani, Takashi Tanaka + Show 11 more

Open Access

https://doi.org/10.1038/s41598-020-78020-y

Copy DOI

Abstract

No alternative tissue-engineered vascular grafts for the abdominal venous system are reported. The present study focused on the development of new tissue-engineered vascular graft using a silk-based scaffold material for abdominal venous system replacement. A rat vein, the inferior vena cava, was replaced by a silk fibroin (SF, a biocompatible natural insoluble protein present in silk thread), tissue-engineered vascular graft (10 mm long, 3 mm diameter, n = 19, SF group). The 1 and 4 -week patency rates and histologic reactions were compared with those of expanded polytetrafluoroethylene vascular grafts (n = 10, ePTFE group). The patency rate at 1 and 4 weeks after replacement in the SF group was 100.0% and 94.7%, and that in the ePTFE group was 100.0% and 80.0%, respectively. There was no significant difference between groups (p = 0.36). Unlike the ePTFE graft, CD31-positive endothelial cells covered the whole luminal surface of the SF vascular graft at 4 weeks, indicating better endothelialization. SF vascular grafts may be a promising tissue-engineered scaffold material for abdominal venous system replacement.

Highlights

No alternative tissue-engineered vascular grafts for the abdominal venous system are reported
We evaluated the patency rate of double-raschel knitted silk fibroin (SF) grafts coated with an SF sponge as an abdominal venous system replacement for the inferior vena cava (IVC) in a rat model
An occluded expanded polytetrafluoroethylene (ePTFE) vascular graft (Fig. 6C, HE × 40) at 3 weeks 3 days showed neutrophils infiltrated inside the graft aggregating around erythrocytes (Fig. 6C, HE × 100, single arrowhead) and lymphocytes (Fig. 6C, HE × 100, double arrowhead), indicating infection and inflammation, respectively. This is the first report of venous replacement using an SF vascular graft in a rat model

Summary

Introduction

No alternative tissue-engineered vascular grafts for the abdominal venous system are reported. A rat vein, the inferior vena cava, was replaced by a silk fibroin (SF, a biocompatible natural insoluble protein present in silk thread), tissueengineered vascular graft (10 mm long, 3 mm diameter, n = 19, SF group). An R0 resection, in which the resection margin is free of cancer cells microscopically, is the only curative treatment for hepato-biliary-pancreatic malignant tumors, such as hepatocellular carcinoma, colorectal liver metastasis, biliary tract cancer, and pancreatic cancer These types of malignant tumors often invade the nearby major abdominal venous system, including the hepatic v ein[1,2], inferior vena cava (IVC)[3], portal vein, and superior mesenteric vein[4,5], leading surgeons to attempt precise and extensive resection of the malignant tumor including the abdominal venous system to achieve an R0 resection. We hypothesized that SF grafts would have a better patency rate than ePTFE grafts

Methods

Results

Conclusion