Molecular Understanding of Endothelial Cell and Blood Interactions with Bacterial Cellulose: Novel Opportunities for Artificial Blood Vessels

Abstract

Cardiovascular disease (CVD) is the main cause of death or invalidism in high-income countries today. Moreover, worldwide demographic changes are aiding CVD’s rapid progression towards the number one killer in middleand low-income countries. The World Health Organisation estimates that if current trends are allowed to continue, about 20 million people will die from CVD by 2015. This group of disorders, which affect the heart and blood vessels, includes coronary heart disease, cerebrovascular disease and peripherial arterial disease, deep vein thrombosis and pulmonary embolism. The main cause of these acute life-threatening conditions is atherosclerosis. Atherosclerotic plaques and restenosis can result in severe occlusions of peripheral and coronary arteries. Current treatments include drug therapy and bypass surgery, and depend on the severity of the disease. All treatments require molecular understanding of the processes that govern atherosclerosis. This is especially important when introducing artificial graft materials in vivo. Generally, the first choice for vascular replacement graft material is the patient’s own vessels, i.e., autologous vessels. If these are in shortage supply or do not exhibit sufficient quality due to, e.g., other diseases or previous surgery, artificial alternatives become necessary. Today, clinics use biomaterials such as expanded polytetrafluorethylene (ePTFE) and polyethylene terephtalate fibre (Dacron®) as prosthetic grafts for reconstructive vascular surgery. However, their performance is dismal in small diameter vessels (>6 mm) like coronary arteries and peripheral arteries below the knee, resulting in early thrombosis and intimal hyperplasia. Therefore, about 10% of patients with CVD are left untreated due to the lack of replacement material for small vessels. Considering the large number of patients who need replacement vessels, the substantial demand for alternative small-caliber grafts is urgent, driving scientists to search for and develop new materials. Recently, this has even led to the use of completely biological vessels. However, the growth of such requires months, rendering them unsuitable for acute situations such as heart infarction, which demand a substitute vessel immediately.