title: A close developmental relationship between the lymphoid and myeloid lineages.
abstract: The classic dichotomy model of hematopoiesis postulates that the first step of differentiation beyond the multipotent hematopoietic stem cell generates the common myelo-erythroid progenitors and common lymphoid progenitors (CLPs). Previous studies in fetal mice showed, however, that myeloid potential persists in the T- and B-cell branches even after these lineages have diverged, indicating that the simple dichotomy model is invalid, at least for fetal hematopoiesis. Nevertheless, CLPs have persisted in models of adult hematopoiesis; results from several groups support the presence of CLPs in bone marrow. Recent evidence challenges the dichotomy model in the adult, and it is proposed here that the alternative myeloid-based model is applicable to both fetal and adult hematopoiesis.
authors.affiliation: Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan. kawamoto@rcai.riken.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawamoto
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage; D042381:Granulocyte Precursor Cells / Q000166:cytology* / Q000276:immunology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology; D006801:Humans; D008214:Lymphocytes / Q000166:cytology* / Q000276:immunology; D018448:Models, Immunological