Identification of a B-1 B cell-specified progenitor

Nat Immunol. 2006 Mar;7(3):293-301. doi: 10.1038/ni1301. Epub 2006 Jan 22.


The B-1 subpopulation of B lymphocytes differs phenotypically and functionally from conventional B-2 B cells. B-1 B cells are proposed to derive from a distinct progenitor, but such a population has not been isolated. Here we identify and characterize a B-1 B cell progenitor whose numbers peaked in fetal bone marrow but were less abundant in postnatal bone marrow. These Lin(-)CD45R(lo-neg)CD19(+) cells responded to thymic stromal lymphopoietin and 'preferentially' reconstituted functional sIgM(hi)CD11b(+)CD5(lo-neg) B-1 B cells, but not sIgM(+)CD11b(-) B-2 B cells, in vivo. These data indicate that the CD45R(lo-neg)CD19(+) population includes B-1 B cell-specified progenitors and support models proposing distinct developmental pathways for B-1 B cells.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antigens, CD / immunology
  • Antigens, CD / metabolism
  • Antigens, Differentiation, B-Lymphocyte / immunology
  • Antigens, Differentiation, B-Lymphocyte / metabolism
  • B-Lymphocytes / cytology*
  • B-Lymphocytes / immunology*
  • Bone Marrow Cells / cytology
  • Bone Marrow Cells / immunology
  • Cell Differentiation / immunology
  • Cell Lineage / immunology*
  • Enzyme-Linked Immunosorbent Assay
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / immunology*
  • Immunohistochemistry
  • Lymphocyte Subsets / cytology*
  • Lymphocyte Subsets / immunology*
  • Mice
  • Mice, Inbred BALB C
  • Phenotype
  • Polymerase Chain Reaction


  • Antigens, CD
  • Antigens, Differentiation, B-Lymphocyte