The Impact of Increasing Concentrations of Ragweed Pollen on the Innate Immune System and Allergic Response of Drosophila melanogaster
Author: Shaila Sachdev
Affiliation: Princeton High School, Princeton, NJ
Keywords: c. innate immunity; q. inflammation
The global warming crisis, caused by human activities, not only affects the environment but also human health. The increase in average annual temperature leads to longer growing seasons and higher pollen concentrations leading to an increase in the development of asthma and atopic allergies. Ragweed pollen happens to be the primary allergen trigger around the globe and affects more than 25 million Americans. Drosophila melanogaster exhibits a similar inflammatory response as humans making it a useful replicate asthma model. Although fruit flies only possess an innate immune system, they are outstanding invertebrate model organisms because they have comparatively simple physiology which allows for easy manipulation while possessing the major organs relevant to asthma. For instance, their trachea is made entirely of epithelial cells and directly exposed to high oxygen pressure and environmentally produced reactive oxygen species (ROS). It is believed that these reactive oxygen species may be generated by pollen which plays a potentially major role in influencing inflammatory responses in the airway epithelium. The purpose of this research is important to understand the extent of ragweed pollen’s ability to induce an allergic reaction in a live biological species. To model this experiment, I will be varying the concentration of ragweed pollen that the fruit flies are exposed to in their food media during their third instar larvae stage. Healthy larvae are usually buried in their food, but upon oxygen deprivation -- due to increased pollen concentration -- they move to the surface, which suggests impairments of the tracheal system. This behavior will be quantified by measuring the percentage of larvae showing this behavior, which will provide information about the availability of oxygen to the epithelial tissue. If Drosophila melanogaster are exposed to ragweed pollen, then they should exhibit oxygen deprivation by remaining at the surface of the food media because ragweed pollen is a reactive oxygen species and presents major mediators of inflammatory responses in the airway epithelium.