Christopher Lindsey, Jr., Biology
"AprA Effects on Dictyostelium Pseudopods"
Christopher Lindsey, a Walla Walla University senior biology student, participated in the 2014 Academic Symposium this spring. Entitled “AprA Effects on Dictyostelium Pseudopods,” Lindsey presented his research and findings:
“AprA is a chemorepellant protein secreted by Dictyostelium, a type of amoeba. In conditions of food shortage, Dictyostelium may secrete AprA causing the colony of cells to migrate away from each other so they are not exhausting the food supply. Dictyostelium will chemotax away from AprA using temporary projections called pseudopods (“fake feet”). I looked at the pseudopod formation of Dictyostelium with and without the presence of an AprA gradient.
“The Texas A&M lab I worked in previously discovered the chemorepellant activity of AprA. Richard Gomer, the biology professor I worked for, was interested in what this protein did on pseudopod formation. I had the opportunity to spend many hours watching, recording, and analyzing Dictyostelium movement and pseudopod formation by filming them through a microscope.”
John Clary, Jr., Biology
“The Incredible Edible Macro® Greens Super Food”
Macro Greens® is a non-allergenic, gluten-free, nutrient-rich super food supplement that claims to increase energy, promote weight loss, increase mental clarity, balance blood sugar, strengthen the immune system and improve digestion. I tested the claim that Macro Greens® strengthens the immune system by examining T-cell proliferation in mice. Mice were fed the “super food” with peanut butter for five weeks. A control group was fed only peanut butter. After week five, the spleens were removed and the cells were harvested. I found that mice that were given Macro Greens® super food demonstrated an increase in T-cell proliferation, which may indicate a healthy immune response.
Cedric Thiel, Jr., Biology
“How Does Chia Affect the Mouse Immune System?”
I studied how chia affects a mouse’s immune response. Chia is touted as a “superfood” in today’s dietary-supplement market. To test the effect of chia on immune function, we fed chia to mice for six weeks, after which the immune response of the mouse was compared to the response of a mouse which wasn’t fed chia. These results demonstrated that chia seems to decrease the immune response of mice, but only for a short period. Chia has been used to treat allergies, and our study may demonstrate the mechanism behind this phenomenon. Our results showed a decrease in T-cell replication. Because T-cells are necessary for the initiation of an allergic response, a reduction in T-cell proliferation may inhibit allergic reactions.
Katelyn Winter, Jr., Biology
“An Investigation of the Effect of Hyssopus Officinalis on T-cell Proliferation in Mice”
This study sought to investigate the effects of hyssop on the mammalian immune system. Hyssopus Officinalis is used as a natural remedy in European/Mediterranean countries for respiratory ailments. “Hyssop” is also referred to in the Bible as a symbol of cleansing and purification. I supplemented an experimental group of mice with hyssop and peanut butter for 6 weeks and a control group with just peanut butter. When I removed the spleens and tested T-cell proliferation, I found that the experimental group had less T-cell proliferation. This potentially indicates that hyssop is a suppressant of T-cell proliferation and potentially of the immune system in general (although the immune system is more complex than just T-cells and evidence from my experiment cannot fully back up the claim that hyssop is an immunosuppressant.).
Frances Leaf, Sr., Biology
"How Do Proteins Regulate a Cell’s Transition From Growth to Development?"
My project involves a soil-growing amoeba called Dictyostelium discoideum, or dicty. This slime mold usually lives as a single-cell amoeba, crawling around the forest floor by itself. However, when it starves, it aggregates with other dicty cells, and they differentiate into stalk and spore cells. These dicty aggregations creatively stick to animals passing by to help them get from a place with no food to another that is plentiful with bacteria to eat. The growth-to-development transition is what we’re interested in... how it goes from a single cell to forming this fruiting body.
Dicty is a good model organ- ism to understand stem cells in humans because they both have similar mechanisms in their growth-to-development transition. Replicating stem cells result in a large pool of undifferentiated cells, but when they encounter a particular stimulus they turn into the type of cell that is needed in the body. For dicty, the stimulus is starvation. dicty uses an ubiquitin-proteasome pathway to help degrade certain proteins at this transition stage.
By experimentation we now know what these proteins are and are currently trying to do experimentation to find out what they do in the cell and why the cell wants to get rid of them.