Page 19 - Improved endothelialization by silicone surface modification and fluid hydrodynamics modulation- Implications for oxygenator biocompatibility Nasim

key limitation for clinical application of artificial lungs [1, 3]. Blood proteins adsorb
to the synthetic hollow fibers surfaces, which can trigger the activation of immune
cells and deposition of clots onto the fibers, resulting in a tendency toward
bleeding, when the blood reenters the patient [1]. Therefore high levels of anticoagulants, such as heparin, are required during ECMO to attempt to minimize 3 thrombus formation associated with blood contact to a foreign surface, which
greatly restricts patient mobility and quality of life, and is associated with high mortality [1].
Figure 1. The native lung provides approximately 70 m2 of gas transfer area in alveoli with actively anticoagulant endothelial surfaces lining the blood vessels. Membrane oxygenators commonly include a pack of hollow fibers across which blood flows. Blood protein deposits on the synthetic hollow fibers lead to the need for anticoagulation therapy.
Fortunately, recent advancements in the field of tissue engineering and biomaterials have increased the biocompatibility of current artificial lungs. A landmark achievement of recent developments is the design of biohybrid artificial lungs. Biohybrid artificial lungs may become a first stepping stone towards introducing regenerative medicine techniques in the treatment of chronic lung disease. Endothelialization of blood contacting surfaces of hollow fibers is a key step to generate a biohybrid artificial lung [3, 5, 6]. Although imitating the delicate structures of the human lung will not be possible in the foreseeable future, the cells that are necessary to create a single cell layer are on hand. These endothelialized
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