Drosophila blood cells.
Drosophila blood cells or haemocytes belong to three lineages: plasmatocytes, crystal cells and lamellocytes. There is no equivalent of a lymphoid lineage in insects which have no adaptive immunity. Haematopoiesis is under the control of a number of transcription factors and signalling pathways (such as GATA factors, JAK/STAT or Notch pathways) most of which have homologues which participate in the control of mammalian haematopoiesis. Drosophila plasmatocytes are professional phagocytes reminiscent of the cells from the mammalian monocyte/macrophage lineage. Several receptors responsible for recognition of microorganisms or apoptotic corpses have been identified, which include a Scavenger Receptor, a CD36 homologue and a peptidoglycan recognition protein. Crystal cells contain the enzymes necessary for humoral melanization that accompanies a number of immune reactions. The production of melanin generates, as by-products, cytotoxic free radicals that are believed to participate in the killing of pathogens. Finally, lamellocytes represent a cell type that specifically differentiates after parasitism of Drosophila larvae and forms a capsule around the invader. Encapsulation together with melanization eventually kill the parasite within the capsule.
Meister
Marie
M
UPR 9022 du CNRS, IBMC, 15 rue René Descartes, 67084 Strasbourg, France. M.Meister@ibmc.u-strasbg.fr
Lagueux
Marie
M
D000818:Animals; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000166:cytology / Q000502:physiology*; D006410:Hematopoiesis / Q000235:genetics / Q000502:physiology*; D006434:Hemocytes / Q000502:physiology* / Q000648:ultrastructure; D015398:Signal Transduction / Q000502:physiology
D029721:Drosophila Proteins