title: Separation of plasmacytoid dendritic cells from B-cell-biased lymphoid progenitor (BLP) and Pre-pro B cells using PDCA-1.
abstract: B-cell-biased lymphoid progenitors (BLPs) and Pre-pro B cells lie at a critical juncture between B cell specification and commitment. However, both of these populations are heterogenous, which hampers investigation into the molecular changes that occur as lymphoid progenitors commit to the B cell lineage. Here, we demonstrate that there are PDCA-1(+)Siglec H(+) plasmacytoid dendritic cells (pDCs) that co-purify with BLPs and Pre-pro B cells, which express little or no CD11c or Ly6C. Removal of PDCA-1(+) pDCs separates B cell progenitors that express high levels of a Rag1-GFP reporter from Rag1-GFP(low/neg) pDCs within the BLP and Pre-pro B populations. Analysis of Flt3-ligand knockout and IL-7Rα knockout mice revealed that there is a block in B cell development at the all-lymphoid progenitor (ALP) stage, as the majority of cells within the BLP or Pre-pro B gates were PDCA-1(+) pDCs. Thus, removal of PDCA-1(+) pDCs is critical for analysis of BLP and Pre-pro B cell populations. Analysis of B cell potential within the B220(+)CD19(-) fraction demonstrated that AA4.1(+)Ly6D(+)PDCA-1(-) Pre-pro B cells gave rise to CD19(+) B cells at high frequency, while PDCA-1(+) pDCs in this fraction did not. Interestingly, the presence of PDCA-1(+) pDCs within CLPs may help to explain the conflicting results regarding the origin of these cells.
authors.affiliation: Department of Immunology, Mayo Clinic, Rochester, Minnesota, United States of America.
authors.forename: Kay L
authors.initials: KL
authors.lastname: Medina
authors.forename: Sarah N
authors.initials: SN
authors.lastname: Tangen
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Seaburg
authors.forename: Puspa
authors.initials: P
authors.lastname: Thapa
authors.forename: Kimberly A
authors.initials: KA
authors.lastname: Gwin
authors.forename: Virginia Smith
authors.initials: VS
authors.lastname: Shapiro
mesh_terms: D000818:Animals; D018941:Antigens, CD19 / Q000276:immunology; D000950:Antigens, Ly / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D039521:CD11c Antigen / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D019070:Cell Lineage / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D058851:GPI-Linked Proteins / Q000276:immunology; D017493:Leukocyte Common Antigens / Q000276:immunology; D008562:Membrane Glycoproteins / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D054448:Precursor Cells, B-Lymphoid / Q000276:immunology*; D011951:Receptors, Complement / Q000276:immunology; D020395:Receptors, Interleukin-7 / Q000276:immunology
chemical_list: D018941:Antigens, CD19; D000950:Antigens, Ly; D039521:CD11c Antigen; D058851:GPI-Linked Proteins; C035271:Ly6d protein, mouse; D008562:Membrane Glycoproteins; D011951:Receptors, Complement; D020395:Receptors, Interleukin-7; C032402:complement 1q receptor; C415350:interleukin-7 receptor, alpha chain; D017493:Leukocyte Common Antigens