Electron microscope studies of Anaplasma marginale in an Aedes albopictus culture system.

Anaplasma marginale was seen by electron microscopy within the cytoplasm of Aedes albopictus cells in culture. Anaplasma marginale was seen in free bovine RBC as well as in RBC phagocytized by Ae albopictus cells. Some A marginale organisms, both intracellular and extracellular, remained intact for as long as 60 days in culture, and Anaplasma inclusion appendages were seen in free-lysed RBC and in lysed RBC phagocytized by Ae albopictus cells. Although some A marginale organisms had deteriorated by day 60, the structure of most A marginale organisms did not change appreciably from that in its natural bovine host. Reproduction of A marginale was not seen.