title: Identification of CD72 as a lymphocyte receptor for the class IV semaphorin CD100: a novel mechanism for regulating B cell signaling.
abstract: We have identified the lymphocyte semaphorin CD100/Sema4D as a CD40-inducible molecule by subtractive cDNA cloning. CD100 stimulation significantly enhanced the effects of CD40 on B cell responses. Administration of soluble CD100 markedly accelerated in vivo antigen-specific antibody responses. CD100 receptors with different binding affinities were detected on renal tubular cells (K(d) = approximately 1 x 10(-9)M) and lymphocytes (K(d) = approximately 3 x 10(-7)M). Expression cloning revealed that the CD100 receptor on lymphocytes is CD72, a negative regulator of B cell responsiveness. CD72 thus represents a novel class of semaphorin receptors. CD100 stimulation induced tyrosine dephosphorylation of CD72 and dissociation of SHP-1 from CD72. Our findings indicate that CD100 plays a critical role in immune responses by the novel mechanism of turning off negative signaling by CD72.
authors: Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita Osaka 565-0871, Japan.
authors: A
authors: A
authors: Kumanogoh
authors: C
authors: C
authors: Watanabe
authors: I
authors: I
authors: Lee
authors: X
authors: X
authors: Wang
authors: W
authors: W
authors: Shi
authors: H
authors: H
authors: Araki
authors: H
authors: H
authors: Hirata
authors: K
authors: K
authors: Iwahori
authors: J
authors: J
authors: Uchida
authors: T
authors: T
authors: Yasui
authors: M
authors: M
authors: Matsumoto
authors: K
authors: K
authors: Yoshida
authors: H
authors: H
authors: Yakura
authors: C
authors: C
authors: Pan
authors: J R
authors: JR
authors: Parnes
authors: H
authors: H
authors: Kikutani
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D016466:CHO Cells; D006224:Cricetinae; D008562:Membrane Glycoproteins / Q000276:immunology*; D011971:Receptors, Immunologic / Q000276:immunology*; D039961:Semaphorins; D015398:Signal Transduction / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; C093224:CD100 antigen; C064228:CD72 protein, human; D008562:Membrane Glycoproteins; D011971:Receptors, Immunologic; D039961:Semaphorins