title: Human CD100, a novel leukocyte semaphorin that promotes B-cell aggregation and differentiation.
abstract: Herein we describe the molecular characterization of the human leukocyte activation antigen CD100 and identify it as the first semaphorin, to our knowledge, in the immune system. Semaphorins have recently been described as neuronal chemorepellants that direct pioneering neurons during nervous system development. In this study we demonstrate that CD100 induces B cells to aggregate and improves their viability in vitro. We show that CD100 modifies CD40-CD40L B-cell signaling by augmenting B-cell aggregation and survival and down-regulating CD23 expression. Thus, these results suggest that semaphorins as exemplified by CD100 also play a functional role in the immune system.
authors.affiliation: Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: K T
authors.initials: KT
authors.lastname: Hall
authors.forename: L
authors.initials: L
authors.lastname: Boumsell
authors.forename: J L
authors.initials: JL
authors.lastname: Schultze
authors.forename: V A
authors.initials: VA
authors.lastname: Boussiotis
authors.forename: D M
authors.initials: DM
authors.lastname: Dorfman
authors.forename: A A
authors.initials: AA
authors.lastname: Cardoso
authors.forename: A
authors.initials: A
authors.lastname: Bensussan
authors.forename: L M
authors.initials: LM
authors.lastname: Nadler
authors.forename: G J
authors.initials: GJ
authors.lastname: Freeman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015703:Antigens, CD; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D019013:CD40 Antigens / Q000502:physiology; D019556:COS Cells; D002449:Cell Aggregation; D002454:Cell Differentiation; D002470:Cell Survival; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008213:Lymphocyte Activation; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology*; D008969:Molecular Sequence Data; D009928:Organ Specificity; D012333:RNA, Messenger / Q000096:biosynthesis; D017455:Receptors, IgE / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000276:immunology; D039961:Semaphorins; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D015703:Antigens, CD; C093224:CD100 antigen; D019013:CD40 Antigens; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D017455:Receptors, IgE; D011994:Recombinant Proteins; D039961:Semaphorins