Meeting Abstract
P2.144 Saturday, Jan. 5 Quantifying hemocyte population changes in Manduca sexta larvae after x-ray irradiation damage HONG, T.*; MIRY, S.; CISNEROS, B.; FUSE, M.; San Francisco State University; San Francisco State University; San Francisco State University; San Francisco State University tiffanyihong@yahoo.com
Hemocytes, or insect blood cells, are comprised of about five classes of cells that play key roles in an insect’s life cycle and in its immune responses. Immune responses include phagocytosis of invading microbes in a similar fashion to the actions of human macrophages, encapsulation and melanization of larger invaders like parasitic wasp eggs, and cell signaling through the JAK/STAT pathway in response to general tissue damage. The larval tobacco hornworm Manduca sexta is a holometabolous insect whose hemocyte population has been quantified under different developmental and immune cues, largely through the use of manual hemocytometry. We therefore sought to (i) develop a flow cytometry technique in the lab to easily quantify hemocyte populations, by comparing our data to that derived by manual hemocytometry, and (ii) quantify changes in the hemocyte population after selectively damaging the highly proliferating imaginal discs using x-ray irradiation. We noted hemocyte populations on the order of 106-107 cells, using both methods. Moreover, the population was significantly reduced after tissue damage through x-ray irradiation, but not after manual fracturing of the discs. These differences suggest that x-rays may do more than damage imaginal discs, as was previously suggested.
