University of Indianapolis, Biology, Indianapolis, IN 46227
Stem cells are responsible for the production of differentiated cells throughout the lifetime of an organism. However, in the adult Drosophila, there is no identified site of de novo blood cell production. During the larval stages of Drosophila development, the lymph gland is the known organ responsible for haematopoiesis. By the pupa stage in the Drosophila life cycle, the lymph gland falls apart and releases all of the blood cells into circulation, contributing many of the hemocytes present in the adult fly. To investigate the existence of an adult hematopoietic organ or site, confocal imaging techniques were used to view the expression pattern of blood-specific promoters labeled with green fluorescent protein in adult Drosophila abdominal tissue. In order to further provide a means to distinguish precursors from differentiated cells, fluorescent microspheres were injected into adult flies to solicit the phagocyitic response capable of only differentiated cells. The value of Drosophila as a model system to bolster our understanding of hematopoeiesis, can influence the understanding of similar mechanisms in vertebrate systems including humans.
[Abstract (DOC)]