Introduction: The infection rate of artificial blood vessels after the operations for infected aneurysms or vascular infections was reported to be about 16%. An omental flap is commonly used to prevent infection but is often not available in cases like after gastrectomy.
The amniotic membrane is a physically tough membrane, and amniotic membrane derived cells are known to have antibacterial effects by secreting βdefensin, elafin, and secretory leukocyte peptidase inhibitor (SLPI), anti-inflammatory effects by secreting anti-inflammatory cytokines, and wound healing effects by secreting wound healing factors. Because of these characteristics, the amniotic membrane has been used to treat ulcers and burns. Also, the amniotic membrane is already commonly used in ophthalmology. In this study, we aimed to establish a method of preventing infection of artificial blood vessels using the amniotic membrane.
Method: The amniotic membrane was aseptically removed from the placenta of a woman who had given birth by Cesarean section at Tohoku University Hospital and used for the experiment. A subcutaneous pocket was created in the back of male rats, and 0.1 g of cecal contents and an artificial blood vessel cut into a 3 x 3 mm square and covered with amniotic membrane were implanted. After seven days, the artificial blood vessel is removed from the abscess, and the presence of inflammatory cells and bacteria on the surface of the artificial blood vessel is evaluated by HE staining and Gram staining.
Result: Macroscopically, no disruption of the amnion was observed. HE staining and Gram staining revealed no direct infiltration of inflammatory cells or bacteria on the surface of the amniotic membrane-coated vessels.
Conclusion: The amniotic membrane prevented bacterial leaching onto the surface of the artificial vessel.In patients who need artificial vessel replacement in an infected wound, the ability to isolate the wound from the surrounding area for seven days and prevent bacterial invasion is clinically very significant. We are currently working to determine whether antimicrobial peptides such as βdefensin, elafin, and SLPI are involved in these results.