CMU Students Ride Vomit Comet Over Spring Break
Although plenty of students probably experienced feelings of dizziness and vomiting over their spring break, it?s doubtful that they were studying astrobiology 30,000 feet above the ground at the time.
After spending months in space, astronauts return to earth with reduced bone mass, atrophied muscles, and decreased immune responses. To help understand why, four Carnegie Mellon students ran an experiment on NASA?s ?Vomit Comet? at Johnson Space Center in Houston on March 11 and 12. The ?Comet? is a KC-135A aircraft that dives from 30,000 to 3000 feet, exposing its occupants to forces of zero Gs at its highest point and two Gs at its lowest. One ?G? is about the amount of gravity you?re experiencing right now.
James Torchia and Candi Spier, senior biological sciences majors, Sujata Emani, a junior chemistry major, and Caroline Chen, a junior biological sciences major, who call themselves ?Team Conscius,? tested the effect of low gravity on cells as part of NASA?s Reduced Gravity Student Flight Opportunities program (microgravityuniversity.jsc.nasa.gov).
Spier and Torchia had discussed the program in their first year at CMU, but didn?t seriously think about participating until this year.
?I remembered this program over the summer out of the clear blue,? said Torchia. ?I wanted to come up with a project I could do on [the Comet], so I did a literature search.? He found that actin, a core component of a cell?s cytoskeleton that could play a role in the physical problems astronauts experience, was a topic ripe for reduced-gravity research.
Previous research had found that structures that are called microtubules, similar to the protein actin, become disorganized in space, so it may be that filaments of actin do the same. When actin forms filaments, it starts a process called signal trafficking, which impacts whether the cell gets weaker or stronger. If the process is disrupted, it could affect the cell?s organization, which in bone and immune cells may cause the astronauts? decreased bone mass and immunity.
Once Torchia had decided on a topic, the rest of the team came together. Since Emani wants to be an astronaut, she was a natural choice. ?She?s been to space camp, and she?s hardcore,? said Chen.
Torchia overheard Emani and Chen talking in class about Emani?s astronaut dream. ?Caroline thought it was cool too, so I thought, that?d be awesome, they?d probably want to be in my group then,? said Torchia. ?Then I remembered Candi told me about the program a long time ago, so I asked her about it too,? he said.
They used cells similar to neutrophils, a type of immune cell, but their research could apply to actin formation in other types of cells as well. The cell culture they used came from Daniel Johnson?s lab at the University of Pittsburgh Cancer Institute, where Torchia works.
To simulate low gravity, the team went up in the aircraft over a period of two days, two members at a time: Torchia and Emani went the first day, Chen and Spier the second. They tested their cells at various time intervals at zero and two Gs (and, back on the ground, at one G).
At any given time, doctors, flight staff and 12 students were on the aircraft. During the week Team Conscius flew, students from 12 colleges participated. Sixty-nine schools are participating in the program.
In a recent Carnegie Mellon News story, Spier, Torchia, and Emani were depicted as thrill-seeking adventurers (Spier skydives, Torchia is getting his pilot?s license, and Emani dreams of being in space); the article, however, said that Chen would be ?medicated on Dramamine? for the ride, implying that she was most likely to throw up. In fact, Spier was the only one to fulfill the promise of the Comet?s name (Emani did too, but back on the ground). The students were given a combination stimulant and depressant called Scope-Dex, a mixture of scopolamine and Dexedrine: a muscle relaxant to reduce nausea and vomiting and an alertness medicine, respectively. But, it turned out, it worked a bit too well.
?The upper overcompensated for the downer,? said Torchia. ?We were bouncing off the walls.?
But the students? trip to Houston included time on the ground as well. In their free time, NASA folks suggested restaurants and clubs for them to visit. They toured Mission Control, went to astronaut briefings, and, as Spier mentioned offhandedly, even had dinner ?with a few astronauts.?
Now back in Pittsburgh, they will analyze their results using the techniques of flow cytometry and fluorescence microscopy. After exposing the cells to a fluorescent marker that binds to actin, they will be able to see the actin in the cells under a fluorescence microscope. Then they can find out how different gravities affect actin development and how they affect cell organization.
Elizabeth Jones, head of the biology department, secured a Howard Hughes Medical Institute grant for the team, which also got a Small Undergraduate Research Grant (SURG). The team will present its research at CMU?s Meeting of the Minds undergraduate research conference in May.
As part of the NASA program, they must do an outreach project. They?re planning to work with the nonprofit organization Center of Life in the Hazelwood neighborhood to enhance underprivileged students? exposure to science.
With the help of Barry Luokkala, a principal lecturer in physics, the students also plan to teach a course on astrobiology this summer as part of the Pennsylvania Governor?s School for the Sciences. The high school students in the course will not only learn about the effects of outer space on the human body, they?ll also get a chance to see the results of Team Conscius? experiments and do their own experiments using the same cells and techniques the students used on the Comet.