SpaceX launched its 17th resupply mission to the International Space Station on May 4, with bioengineering professor Dan Huh’s organ-on-a-chip experiments in tow.
Dan Huh, the Wilf Family Term Assistant Professor in the Department of Bioengineering, researches human organs and the diseases that infect them by engineering devices made of living cells that act as stand-ins for organs. Huh’s lab has developed imitations of many organs, including the placenta and the eye, but it’s his lung-on-a-chip and his bone-marrow-on-a-chip that are reaching unprecedented heights as part of a new experiment taking place at the International Space Station (ISS).
On May 4, SpaceX launched a ISS-bound cargo capsule carrying Huh’s organ-on-a-chip experiments, which will remain in space for a month. Once back on Earth, the chips that spent time in space will be compared to control chips from Huh’s lab that are being monitored in parallel. Huh’s team is looking to see how being in space affects bacterial infections in lungs and white blood cell behavior in bone marrow. The researchers’ hope is that their studies will reveal important information about how human organs function both in space and on Earth.
Daniel Oberhaus of WIRED wrote an article describing the multiple organs-on-a-chip experiments being conducted at the ISS, including the two experiments headed by Huh:
Dan Huh is a bioengineer at the University of Pennsylvania and the lead researcher on the lung tissue chip headed to the ISS. This lung chip models a human airway and will be infected with Pseudomonas aeruginosa, a species of bacteria that had previously been found on the ISS. On Earth this bacteria is usually associated with respiratory infections, which are one of the leading types of illness on long-duration missions to the ISS.
Huh says scientists still know very little about why astronauts’ immune response seems to become suppressed in orbit, and the tissue chips are aimed at building a better understanding of the phenomenon.
Throughout the 60-year history of the U.S. space program—from the Mercury capsules of the 1960s to today’s International Space Station—astronauts have been getting sick. Researchers know being in orbit seems to suppress their immune systems, creating a more fertile ground for infections to grow. But nobody really understands why.
Early on the morning of April 26, a SpaceX Falcon 9 rocket will launch a cargo mission to the ISS from Cape Canaveral Air Force Station. Along with fresh water, food, and other necessities for the crew, the craft will be carrying two experiments designed by Penn scientists that could help shed light on why bugs have bedeviled space travelers.
Every undergraduate student pursuing a B.S.E. in Bioengineering participates in the Bioengineering Modeling, Analysis, and Design Laboratory I & II courses, in which students work together on a series of lab-based design challenges with an emphasis on model development and statistical analysis. Recently, junior undergraduates enrolled in this course taught by Dr. Brian Chow and Dr. David Issadore (both of whom recently received tenure) completed a project involving the use of electrocardiography (ECG) to innovate a non-invasive fatigue-monitoring device for astronauts that tend to fall asleep during long operations in space.
Using ECG lead wires and electrodes with a BioPac M-35 data collection apparatus, students collected raw data of their own heart and respiration rates, and loaded the data into MATLAB to analyze and calculate information like the heart rate itself, and portions of it like the QT-interval. “I think it was cool that we could measure signals from our own body and analyze it in a way that let us use it for a real-world application,” said junior Melanie Hillman about the project.
After taking these preliminary measurements, students used a combination of circuitry, MATLAB, and data acquisition boards to create both passive and active filters for the input signals. These filters helped separate the user’s breathing rate, which occurs at lower frequencies, from the heart rate, which occurs at higher frequencies, allowing for the data to be read and analyzed more easily. In their final design, most students used an active filter circuit chip that combined hardware with software to create bandpass filters of different frequency ranges for both input signals.
“It was nice to be able to do a lab that connected different aspects of engineering in the sense that we both electronically built circuits, and also modeled them theoretically, because normally there’s a separation between those two domains,” said junior Emily Johnson. On the final day of the project, Demo Day, groups displayed their designs ability to take one input from the ECG cables connected to a user, and filter it out into recognizable heart and respiration rates on the computer. This project, conducted in the in the Stephenson Foundation Bioengineering Educational Laboratory here at the University of Pennsylvania’s Department of Bioengineering, is just one of many examples of the way this hallmark course of the bioengineering curriculum strives to bring together all aspects of students’ foundational engineering coursework into applications with significance in the real world.