(5de) Biomimetic Microdevices for Clinical Therapeutic and Diagnostic Applications

Sepsis is a major killer of man because a high microbial load in blood overcomes the immune system resulting in multi-systems failure. This is a particularly significant problem in premature infants and immunocompromised patients with fungal infections since antibiotic therapies are dose-limiting. Development of an extracorporeal blood cleansing device that can rapidly clear the blood of pathogens without loss or alteration of normal blood components could help remedy this problem. We have previously developed a prototype microfluidic-micromagnetic blood cleansing device that rapidly clears living Candida albicans pathogens from flowing human whole blood with high efficiency (80%) and throughput (20 mL/hr/device) in a single pass. Magnetic opsonins were created by coating 1-μm microbeads with pathogen-specific antibodies. One drawback of this device is that some blood is loss in the saline stream (~13%) during the separation process. More recently, we have developed an advanced design inspired by the native architecture of the spleen that virtually eliminates blood loss while further enhancing separation efficiency. This Biomimetic Spleen has three microfluidic layers that replicate the microvasculature, sinusoids, and lymphoid follicles of the organ. The result is a simple and yet robust device that can clear 85-95% of C.albicans at similar flow rates without any blood loss or dilution. (Funded by CIMIT, DoD, Wyss Institute)