title: Eotaxin modulates myelopoiesis and mast cell development from embryonic hematopoietic progenitors.
abstract: Eotaxin is a potent chemoattractant for eosinophils during inflammation and allergic reactions in the adult, but its role in the embryonic development of the hematopoietic system has not been examined. We report here that eotaxin and its receptor, CCR-3, are expressed by embryonic tissues responsible for blood development, such as fetal liver (FL), yolk sac (YS), and peripheral blood. We found that eotaxin acts synergistically with stem cell factor to accelerate the differentiation of embryonic mast cell progenitors, and this response can be suppressed by pertussis toxin, an inhibitor of chemokine-induced signaling through Gialpha protein and chemotaxis. Eotaxin promotes the differentiation of fetal mast cell progenitors into differentiated mast cells as defined by the expression of mast cell specific proteases. Furthermore, in combination with stem cell factor (SCF), it promotes the growth of Mac-1(+) myeloid cells from embryonic progenitors. These studies suggest that eotaxin may be involved in the growth of granulocytic progenitors and the differentiation and/or function of mast cells during embryogenesis and/or pathological conditions that induce high levels of eotaxin, such as allergic responses.
authors.affiliation: The Center for Blood Research, the Department of Genetics, Harvard Medical School, Cambridge, MA, USA.
authors.forename: E J
authors.initials: EJ
authors.lastname: Quackenbush
authors.forename: B K
authors.initials: BK
authors.lastname: Wershil
authors.forename: V
authors.initials: V
authors.lastname: Aguirre
authors.forename: J C
authors.initials: JC
authors.lastname: Gutierrez-Ramos
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D054413:Chemokine CCL11; D019742:Chemokines, CC; D002631:Chemotactic Factors, Eosinophil / Q000096:biosynthesis / Q000502:physiology*; D016207:Cytokines / Q000096:biosynthesis / Q000502:physiology*; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005260:Female; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D019891:Leukopoiesis / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008407:Mast Cells / Q000166:cytology* / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000096:biosynthesis; D015017:Yolk Sac / Q000098:blood supply / Q000378:metabolism
chemical_list: C515457:Ccl11 protein, mouse; D054413:Chemokine CCL11; D019742:Chemokines, CC; D002631:Chemotactic Factors, Eosinophil; D016207:Cytokines; D012333:RNA, Messenger