title: Rat embryonic mast cells originate in the AGM.
abstract: Mast cells originate from pluripotent hematopoietic stem cells. Two mast cell specific antibodies, mAbsAA4 and BGD6, have previously been used to identify and study committed mast cell precursors (MCcps) in the bone marrow of adult mice and rats. However, the embryonic origin of MCcps is still not known. In the present study, we identified MCcps in rat embryos using these previously characterized mast cell specific antibodies. The MCcps were found in the AGM (aorta-gonad-mesonephros) region of rat embryos at E11.5. These cells were BGD6+, CD34(+), c-kit(+), CD13(+), FcεRI(-), AA4(-) CD40(-), and Thy-1(-). By PCR the cells contained message for the α and β subunits of FcεRI and mast cell specific proteases. In vitro, the MCcps differentiated into metachromatic mast cells. With age of gestation the percent of MCcps diminished while the percent of mast cell progenitors increased. An increased knowledge of the biology and embryonic origin of mast cells may contribute to a greater understanding of allergy, asthma, and other mast cell related diseases.
authors.affiliation: Department of Cell and Molecular Biology and Pathogenic Bioagents, Faculdade de Medicina de Ribeirão Preto-University of São Paulo, Ribeirão Preto, Brazil.
authors.forename: Michel Farchi
authors.initials: MF
authors.lastname: Guiraldelli
authors.forename: Carolina Nunes
authors.initials: CN
authors.lastname: França
authors.forename: Devandir Antonio
authors.initials: DA
authors.lastname: de Souza
authors.forename: Elaine Zayas Marcelino
authors.initials: EZ
authors.lastname: da Silva
authors.forename: Vanina Danuza
authors.initials: VD
authors.lastname: Toso
authors.forename: Celiane Cardoso
authors.initials: CC
authors.lastname: Carvalho
authors.forename: Maria Célia
authors.initials: MC
authors.lastname: Jamur
authors.forename: Constance
authors.initials: C
authors.lastname: Oliver
mesh_terms: D000818:Animals; D001011:Aorta / Q000196:embryology* / Q000378:metabolism; D002454:Cell Differentiation; D005260:Female; D006066:Gonads / Q000196:embryology* / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D018189:Immunomagnetic Separation; D008099:Liver / Q000196:embryology / Q000378:metabolism; D008297:Male; D008407:Mast Cells / Q000166:cytology* / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D008650:Mesonephros / Q000196:embryology* / Q000378:metabolism; D051381:Rats; D011951:Receptors, Complement / Q000378:metabolism; D017455:Receptors, IgE / Q000235:genetics / Q000378:metabolism
chemical_list: C553474:FCER1A protein, rat; D008562:Membrane Glycoproteins; D011951:Receptors, Complement; D017455:Receptors, IgE; C032402:complement 1q receptor