title: Distinct Transcriptomic Features are Associated with Transitional and Mature B-Cell Populations in the Mouse Spleen.
abstract: Splenic transitional B-cells (T1 and T2) are selected to avoid self-reactivity and to safeguard against autoimmunity, then differentiate into mature follicular (FO-I and FO-II) and marginal zone (MZ) subsets. Transcriptomic analysis by RNA-seq of the five B-cell subsets revealed T1 cell signature genes included RAG suggesting a potential for receptor revision. T1 to T2 B-cell differentiation was marked by a switch from Myb to Myc, increased expression of the PI3K adapter DAP10 and MHC class II. FO-II may be an intermediate in FO-I differentiation and may also become MZ B-cells as suggested by principle component analysis. MZ B-cells possessed the most distinct transcriptome including down-regulation of CD45 phosphatase-associated protein (CD45-AP/PTPRC-AP), as well as upregulation of IL-9R and innate molecules TLR3, TLR7, and bactericidal Perforin-2 (MPEG1). Among the endosomal TLRs, stimulation via TLR3 further enhanced Perforin-2 expression exclusively in MZ B-cells. Using gene-deleted and overexpressing transgenic mice we show that IL-9/IL-9R interaction resulted in rapid activation of STAT1, 3, and 5, primarily in MZ B-cells. Importantly, CD45-AP mutant mice had reduced transitional and increased mature MZ and FO B-cells, suggesting that it prevents premature entry of transitional B-cells to the mature B-cell pool or their survival and proliferation. Together, these findings suggest, developmental plasticity among splenic B-cell subsets, potential for receptor revision in peripheral tolerance whereas enhanced metabolism coincides with T2 to mature B-cell differentiation. Further, unique core transcriptional signatures in MZ B-cells may control their innate features.
authors.affiliation: Department of Microbiology and Immunology, Miller School of Medicine, University of Miami , Miami, FL , USA.
authors.forename: Eden
authors.initials: E
authors.lastname: Kleiman
authors.affiliation: Center for Computational Science, University of Miami , Miami, FL , USA.
authors.forename: Daria
authors.initials: D
authors.lastname: Salyakina
authors.affiliation: Ludwig Institute for Cancer Research, Brussels Branch , Brussels , Belgium ; de Duve Institute, Université Catholique de Louvain , Brussels , Belgium.
authors.forename: Magali
authors.initials: M
authors.lastname: De Heusch
authors.affiliation: Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine , Nashville, TN , USA.
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Hoek
authors.affiliation: Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine , Nashville, TN , USA.
authors.forename: Joan M
authors.initials: JM
authors.lastname: Llanes
authors.affiliation: Department of Microbiology and Immunology, Miller School of Medicine, University of Miami , Miami, FL , USA.
authors.forename: Iris
authors.initials: I
authors.lastname: Castro
authors.affiliation: Department of Microbiology and Immunology, Miller School of Medicine, University of Miami , Miami, FL , USA.
authors.forename: Jacqueline A
authors.initials: JA
authors.lastname: Wright
authors.affiliation: Department of Microbiology and Immunology, Miller School of Medicine, University of Miami , Miami, FL , USA.
authors.forename: Emily S
authors.initials: ES
authors.lastname: Clark
authors.affiliation: Hussman Institute for Human Genomics, University of Miami , Miami, FL , USA.
authors.forename: Derek M
authors.initials: DM
authors.lastname: Dykxhoorn
authors.affiliation: Center for Computational Science, University of Miami , Miami, FL , USA.
authors.forename: Enrico
authors.initials: E
authors.lastname: Capobianco
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine in St. Louis , St. Louis, MO , USA.
authors.forename: Akiko
authors.initials: A
authors.lastname: Takeda
authors.affiliation: Ludwig Institute for Cancer Research, Brussels Branch , Brussels , Belgium ; de Duve Institute, Université Catholique de Louvain , Brussels , Belgium.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Renauld
authors.affiliation: Department of Microbiology and Immunology, Miller School of Medicine, University of Miami , Miami, FL , USA.
authors.forename: Wasif N
authors.initials: WN
authors.lastname: Khan
keywords: DAP10 PI3K pathway; IL-9/IL-9R; Myb Myc; Toll-like receptors 3 and 7; follicular 1 and 2 B-cells; marginal zone B-cells; splenic transitional B-cells; transcriptome by RNA-seq technique