I wrote this short paper freshman year for a biomedical engineering introductory seminar. The paper focuses on a technical report of an experiment where rat hearts underwent perfusion decellularization and then were recellularized to be fully functional. In this process, the rat hearts were washed with a complex mix of detergents which removed all cellular matter from the heart, leaving the organ’s protein matrix intact. The organ matrices were then re-seeded with stem cells from each rat. Using a device designed to deliver nutrients and maintain the proper environment, the stem cells multiplied and recellularized each heart. The hearts were then transplanted back into rats. The paper demonstrates my ability to navigate, analyze, and comprehensively explain technical reports. It also demonstrates my ability to identify and assess the potential impacts and significance of new technology. The following excerpt is from the second paragraph of the paper.
There are many components involved in perfusion decellularization. The process begins with an intact heart. In a technical study of the device, eight cadaveric rat hearts were selected for the process (Ott, Taylor, 2008). The heart is placed in a Langendorff apparatus for decellularization. A Langendorff apparatus is a device designed to perfuse an organ with a specified mixture, usually nutrients and oxygen (Enersen, 2010). The heart is then washed with a specialized detergent solution. In the previously mentioned technical study, several different detergents were used on the rat hearts and the results compared. The detergents used were SDS (sodium lauryl sulfate), polyethylene glycol, enzyme-based protocols, and Triton-X100. SDS works by solubilizing cytoplasmic and nuclear cellular membranes. Triton-X100 disrupts lipid-lipid and lipid-protein interactions, but leaves protein-protein interactions alone (Gilbert, 2006). The function of these detergents is to remove all cellular components from an organ, such as DNA and intracellular structural proteins. After perfusion with a detergent, what remains of the heart is only the extracellular matrix (EMC). Structural fibers, such as collagens, laminin, and fibronectin remain, which serve to retain the structure and shape of the original heart.
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