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Minoru Fukuda - One of the best experts on this subject based on the ideXlab platform.
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Leukosialin a major sialoglycoprotein defining leucocyte differentiation
Ciba Foundation Symposium 145 - Carbohydrate Recognition in Cellular Function, 2007Co-Authors: Minoru FukudaAbstract:We have isolated a major sialoglycoprotein on leucocytes and found that this glycoprotein, termed Leukosialin, is ubiquitously present on various human leucocytes (granulocytes, monocytes/macrophages and T lymphocytes). Our studies showed that Leukosialin is significantly glycosylated by O-linked oligosaccharides (70 chains/molecule). The polypeptide portions of these molecules are, however, apparently the same, with a molecular mass of 38.5 kDa. The amino acid sequence derived from cDNA shows tandemly repeated O-glycan attachment sequences, and about 70% of the serine or threonine residues in the external domain are modified by O-glycans. The structures of those O-linked oligosaccharides are characteristic of each cell lineage and maturation stage. In particular, we have shown that O-glycans of Leukosialin are converted from NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-6)]-GalNAc to NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-6)] GalNAc during T cell activation.
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Ciba Foundation Symposium 145 - Carbohydrate Recognition in Cellular Function - Leukosialin, a Major Sialoglycoprotein Defining Leucocyte Differentiation
Ciba Foundation symposium, 2007Co-Authors: Minoru FukudaAbstract:We have isolated a major sialoglycoprotein on leucocytes and found that this glycoprotein, termed Leukosialin, is ubiquitously present on various human leucocytes (granulocytes, monocytes/macrophages and T lymphocytes). Our studies showed that Leukosialin is significantly glycosylated by O-linked oligosaccharides (70 chains/molecule). The polypeptide portions of these molecules are, however, apparently the same, with a molecular mass of 38.5 kDa. The amino acid sequence derived from cDNA shows tandemly repeated O-glycan attachment sequences, and about 70% of the serine or threonine residues in the external domain are modified by O-glycans. The structures of those O-linked oligosaccharides are characteristic of each cell lineage and maturation stage. In particular, we have shown that O-glycans of Leukosialin are converted from NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-6)]-GalNAc to NeuAc(alpha 2-3)Gal(beta 1-3) [NeuAc(alpha 2-3)Gal(beta 1-4)GlcNAc(beta 1-6)] GalNAc during T cell activation.
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Mucin-type O-glycans and Leukosialin
Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 1999Co-Authors: Minoru Fukuda, S TsuboiAbstract:AbstractMucin-type O-glycans on leukocytes acquire functions once they contain core 2 branches, which can be synthesized by core 2 β1,6-N-acetylglucosaminyltransferase (C2GnT). Recently, understanding the roles of mucin-type O-glycans has been significantly advanced by generating transgenic mice overexpressing C2GnT or knockout mice defective in C2GnT. This review article summarizes previous results implicating the roles of mucin-type O-glycans and the most recent studies to test such a hypothesis. These results, taken together, demonstrate that mucin-type O-glycans either facilitate or attenuate cell adhesion depending on the structures of non-reducing termini
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Chapter 8 Leukosialin and the Wiskott-Aldrich syndrome
New Comprehensive Biochemistry, 1996Co-Authors: Minoru FukudaAbstract:Publisher Summary The Wiskott–Aldrich syndrome is characterized by severe eczema, thrombocytopenia and susceptibility to opportunistic infections. The signs and symptoms appear in the first few months after birth, accompanied by bloody diarrhea. The Wiskott–Aldrich syndrome is inherited as an X-linked recessive trait, most likely due to defect(s) in a single locus of the X chromosome. This chapter discusses It was shown by sequential immunoprecipitation that Leukosialin is identical to the glycoprotein defective in the Wiskott–Aldrich syndrome and represents the human counterpart of the “glycophorinlike” molecule isolated from rat thymocytes. This glycoprotein is now termed CD43 but is still often called Leukosialin or occasionally sialophorin. However, these terms designate the same sialoglycoprotein. The most recent study identified a gene in this syndrome that is apparently responsible for this defect. The identification of this gene will provide critical information in future studies for understanding the defect in the Wiskott-Aldrich syndrome.
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tissue specific transcriptional regulation of human Leukosialin cd43 gene is achieved by dna methylation
Journal of Biological Chemistry, 1995Co-Authors: Shinichi Kudo, Minoru FukudaAbstract:Abstract The expression of human Leukosialin (CD43), a major sialoglycoprotein on the surface of hematopoietic cells, is regulated in cell lineage-specific as well as differentiation stage-specific manners. We have shown previously that transcription from the TATA-less promoter is mediated by the transcription factor Sp1, which binds to repeats of a GGGTGG motif in the 5′-flanking sequence. This regulatory region is ubiquitously functional in mammalian cells, providing a high transcriptional potential. No cis-acting element responsible for the specificity of this gene expression was revealed by extensive studies using transient as well as stable expression systems. Here, we demonstrate that DNA methylation plays a key role in Leukosialin gene expression. Southern blot analysis of genomic DNAs from various human cell lines with methylation-sensitive and -insensitive restriction enzymes showed a tight correlation between gene activity and demethylation state of the 5′-region of the Leukosialin gene. Consistent results were obtained from the same analysis of genomic DNAs from various human tissues. In addition, in vitro DNA methylation of the 5′-region drastically reduced transcriptional activity in a transient expression system. These results indicate that DNA methylation around the 5′-region of the Leukosialin gene is required to shut off a high level of transcription. Thus, the tissue-specific expression of the Leukosialin gene is constitutively achieved by alteration of DNA methylation.
Masutaka Furue - One of the best experts on this subject based on the ideXlab platform.
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Molecular mechanisms involved in the migration of epidermal dendritic cells in the skin.
The journal of investigative dermatology. Symposium proceedings, 1999Co-Authors: Koichiro Nakamura, Nami Yasaka, Atsushi Saitoh, Masutaka Furue, Kunihiko TamakiAbstract:The murine epidermis contains two types of dendritic cells (DC), Thy-1 + dendritic epidermal T cells (DETC) and Langerhans cells. In this review, we introduce our data obtained using a skin organ culture system to examine the migratory capacity of DETC and Langerhans cells into the epidermis. DETC or Langerhans cells were depleted by topical application of clobetazole propionate (CP) solution onto the murine ears. CP-treated or untreated ear skin was co-cultured with syngeneic (semisyngeneic, or allogenic, in experiments with Langerhans cells) epidermal cell suspension. We found (i) that donor DETC or Langerhans cells migrated into the CP-treated epidermis as well as into untreated epidermis, (ii) that Leukosialin Ly48 recognized by monoclonal antibody S11 and TNF-α strongly inhibited donor Langerhans cell migration into the epidermis. We mention other molecules that may participate in the migration of Langerhans cells such as chemotactic cytokines, monocyte chemoattractant protein (MCP)-1, TGF-β and skin-homing molecule, cutaneous lymphocyte-associated antigen (CLA) on Langerhans cells.
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Migration of Thy-1+ Dendritic Epidermal Cells (Thy-1+DEC): Ly48 and TNF-α Are Responsible for the Migration of Thy-1+DEC to the Epidermis
The Journal of investigative dermatology, 1994Co-Authors: Kunihiko Tamaki, Anthony A. Gaspari, Atsushi Saitoh, Nami Yasaka, Masutaka FurueAbstract:Abstract Thy-1 + dendritic epidermal cells (Thy-1 + DEC) are mainly T cells that express T-cell receptor γ and δ chains with limited diversity of γδ, mainly γ3δ1; such γ3δ1 TCR-bearing Thy-1 + DEC originate from day 16 fetal thymic cells. To understand the migratory capability of Thy-1 + DEC, we developed an in vitro model, using skin organ culture. First, emigration of Thy1 + DEC from the epidermis was examined. Ear skin from C3H/He mice was separated into two parts and incubated for 3 d with dermal side down. Thy-1 + DEC emigrated from the epidermis into the dermis and then migrated out of the skin into the culture medium. Next, immigration of Thy-1 + DEC into the epidermis was examined. Thy-1 + DEC were depleted in vivo by daily application of clobetazole propionate solution topically onto the ears of C3H/He mice. Seven days later, ear skin was harvested, separated, and cultured with the dermal side up with syngeneic epidermal cell suspensions with a migration chamber for 3 d. It was found that 1) Thy-1 + DEC immigrated into the Thy-1 + DEC depleted epidermis as well as into untreated epidermis, and 2) the migratory capability of Thy-1 + DEC was directly proved by a biolabeling technique with PKH-26. Blocking studies with various antibodies revealed that Leukosialin (S11 monoclonal antibodies) and TNFα were important for Thy-1 + DEC migration. Thus, Thy-1 + DEC retain the potential for migration in vitro , and Leukosialin and TNFα are partially responsible for the migration of Thy-1 + DEC into the epidermis.
Anthony A. Gaspari - One of the best experts on this subject based on the ideXlab platform.
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Migration of Thy-1+ Dendritic Epidermal Cells (Thy-1+DEC): Ly48 and TNF-α Are Responsible for the Migration of Thy-1+DEC to the Epidermis
The Journal of investigative dermatology, 1994Co-Authors: Kunihiko Tamaki, Anthony A. Gaspari, Atsushi Saitoh, Nami Yasaka, Masutaka FurueAbstract:Abstract Thy-1 + dendritic epidermal cells (Thy-1 + DEC) are mainly T cells that express T-cell receptor γ and δ chains with limited diversity of γδ, mainly γ3δ1; such γ3δ1 TCR-bearing Thy-1 + DEC originate from day 16 fetal thymic cells. To understand the migratory capability of Thy-1 + DEC, we developed an in vitro model, using skin organ culture. First, emigration of Thy1 + DEC from the epidermis was examined. Ear skin from C3H/He mice was separated into two parts and incubated for 3 d with dermal side down. Thy-1 + DEC emigrated from the epidermis into the dermis and then migrated out of the skin into the culture medium. Next, immigration of Thy-1 + DEC into the epidermis was examined. Thy-1 + DEC were depleted in vivo by daily application of clobetazole propionate solution topically onto the ears of C3H/He mice. Seven days later, ear skin was harvested, separated, and cultured with the dermal side up with syngeneic epidermal cell suspensions with a migration chamber for 3 d. It was found that 1) Thy-1 + DEC immigrated into the Thy-1 + DEC depleted epidermis as well as into untreated epidermis, and 2) the migratory capability of Thy-1 + DEC was directly proved by a biolabeling technique with PKH-26. Blocking studies with various antibodies revealed that Leukosialin (S11 monoclonal antibodies) and TNFα were important for Thy-1 + DEC migration. Thus, Thy-1 + DEC retain the potential for migration in vitro , and Leukosialin and TNFα are partially responsible for the migration of Thy-1 + DEC into the epidermis.
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Thy 1+ Dendritic Epidermal Cells but not Langerhans Cells Express Ly 48
The Journal of investigative dermatology, 1993Co-Authors: Anthony A. Gaspari, Barbara Ferbel, John G. FrelingerAbstract:Leukosialin (Ly 48) is a sialoprotein expressed by bone marrow – derived cells early in their development. To determine whether Ly 48 is expressed by specific subsets of epidermal cells (ECs) such as Langerhans cells, keratinocytes, or dendritic epidermal T cells (DETCs), we utilized flow cytometry to detect staining of ECs by a panel of four monoclonal antibodies (S11, S15, S7, and 3E8) that recognize two different epitopes of the Leukosialin antigen. Approximately 2.0% of unfractionated ECs expressed Ly 48, as demonstrated by reactivity with the monoclonal antibodies St11 and S15. Similarly, immunoblots of unfractionated EC lysates revealed an antigen of 125 kD apparent molecular weight that reacted with the S11 monoclonal antibody. Enrichment or depletion of various EC populations indicated that DETCs are the only EC population that express Ly 48. Studies of long-term cultured DETC lines indicated a marked heterogeneity of expression of Ly 48 epitopes. The function(s) of Ly 48 on DETCs as well as T-cell receptor α/β bearing mouse T cells remains to be determined.
C. Foa - One of the best experts on this subject based on the ideXlab platform.
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monocytic THP-1 cells to red blood cells
2015Co-Authors: M. Soler, C. Merant, C. Servant, M. Fraterno, T C. Allasia, T J. C. Lissitzky, P. Bongr, C. FoaAbstract:Leukosialin (CD43) behavior during adhesion of huma
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Glycocalyx modulation is a physiological means of regulating cell adhesion.
Journal of cell science, 2000Co-Authors: S Sabri, M. Soler, C. Foa, A Pierres, A Benoliel, P BongrandAbstract:Here we present experimental evidence that phagocytic cells use modulation of specific components of their glycocalyx to regulate their binding capacity. Particles coated with antibodies specific for the CD32 medium affinity IgG receptor were driven along human monocytic THP-1 cells (expressing CD32) in a flow chamber operated at low shear rate. Surprisingly, only minimal adhesion was observed. However, when cells were activated by exposure to fibronectin-coated surfaces and/or soluble &ggr; interferon, adhesion efficiency was dramatically increased, whereas the apparent glycocalyx thickness displayed 20% decrease, and the surface density of CD43/Leukosialin carbohydrate epitopes displayed 30-40% decrease on activated cells. The existence of a causal link between adhesion increase and glycocalyx alteration was strongly supported by the finding that (i) both phenomena displayed similar kinetics, (ii) an inverse relationship between THP-1 cell binding capacity and glycocalyx density was demonstrated at the individual cell level, and (iii) adhesion enhancement could not be ascribed to an increased binding site density or improved functional capacity of activated cells. Additional experiments revealed that cell-to-particle adhesion resulted in delayed (i.e. more than a few minutes) egress of CD43/Leukosialin from contact areas. Since the time scale of particle attachment was less than a second, surface mobility should not affect the potential of CD43 to impair the initial step of adhesion. Finally, studies performed with fluorescent lectins suggested that THP-1 cell activation and increased adhesive potential were related to a decrease of O-glysosylation rather than N-glycosylation of surface glycoproteins.
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Leukosialin (CD43) behavior during adhesion of human monocytic THP‐1 cells to red blood cells
Journal of leukocyte biology, 1997Co-Authors: M. Soler, C. Merant, C. Servant, M. Fraterno, C Allasia, J C Lissitzky, Pierre Bongrand, C. FoaAbstract:To understand the modulation and the be- havior of glycocalyx elements during adhesion, we ex- plored one ofits components, the CD43 molecule, on human monocytic THP-1 cells exposed to cytokine stimulation and its redistribution during heterotypic adhesion to opsonized erythrocytes. First we demon- strated by immunofluorescence and immunoprecipi- tation that CD43 is dys-sialylated in monocytic THP-1 cells stimulated by interferon-'y (IFN-'y) and tumor ne- crosis factor a (TNF-a) and stimulation increased cor- related to heterotypic adhesion. CD43 anti-adhesive effect seemed to be related to sialic acid moeties be- cause an increase in adhesion was also induced by si- alidase treatment and by monoclonal antibodies rec- ognizing sialic acid-dependent epitopes on CD43. Second, a redistribution of CD43 molecules was ob- served after adhesion, resulting in the exclusion of CD43 molecules from contact areas as demonstrated by immunofluorescence and by ultrastructural immuno- gold localization. We therefore demonstrated in mono- cytic THP-1 cells that some glycocalyx molecules can be modulated by cytokines and redistributed during adhesion. These results support the concept that CD43 can regulate cell interactions. J. Leukoc. Biol. 61: 609-618; 1997.
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Leukosialin cd43 behavior during adhesion of human monocytic thp 1 cells to red blood cells
Journal of Leukocyte Biology, 1997Co-Authors: M. Soler, C. Merant, C. Servant, M. Fraterno, C Allasia, J C Lissitzky, Pierre Bongrand, C. FoaAbstract:To understand the modulation and the be- havior of glycocalyx elements during adhesion, we ex- plored one ofits components, the CD43 molecule, on human monocytic THP-1 cells exposed to cytokine stimulation and its redistribution during heterotypic adhesion to opsonized erythrocytes. First we demon- strated by immunofluorescence and immunoprecipi- tation that CD43 is dys-sialylated in monocytic THP-1 cells stimulated by interferon-'y (IFN-'y) and tumor ne- crosis factor a (TNF-a) and stimulation increased cor- related to heterotypic adhesion. CD43 anti-adhesive effect seemed to be related to sialic acid moeties be- cause an increase in adhesion was also induced by si- alidase treatment and by monoclonal antibodies rec- ognizing sialic acid-dependent epitopes on CD43. Second, a redistribution of CD43 molecules was ob- served after adhesion, resulting in the exclusion of CD43 molecules from contact areas as demonstrated by immunofluorescence and by ultrastructural immuno- gold localization. We therefore demonstrated in mono- cytic THP-1 cells that some glycocalyx molecules can be modulated by cytokines and redistributed during adhesion. These results support the concept that CD43 can regulate cell interactions. J. Leukoc. Biol. 61: 609-618; 1997.
John G. Frelinger - One of the best experts on this subject based on the ideXlab platform.
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Disregulated expression of CD43 (Leukosialin, sialophorin) in the B cell lineage leads to immunodeficiency.
Journal of immunology (Baltimore Md. : 1950), 1996Co-Authors: J R Ostberg, Leonard L. Dragone, Richard K. Barth, T Driskell, Jan A. Moynihan, Richard P. Phipps, John G. FrelingerAbstract:Leukosialin (CD43 or sialophorin) is a cell surface sialoglycoprotein implicated in cell adhesion and proliferation whose tightly regulated expression in B lymphocytes is likely important for their normal development and/or function. To examine the physiologic role of mouse CD43 (mCD43) in vivo, we exploited transgenic (TG) mice whose developmental expression of mCD43 was extended during B cell differentiation so that mCD43 was now expressed on peripheral B cells. Despite having increased B cells, localization of lymphocytes in the TG spleens appeared normal by immunocytochemistry with anti-CD4, anti-CD8, and anti-B220 mAbs. However, the numbers of splenic germinal centers and the resting sera Ig levels were decreased in the TG mice compared with littermate controls. TG mice had decreased humoral responses to the T-dependent Ags keyhole limpet hemocyanin and OVA, as well as reduced Ag-specific B cell numbers. In contrast, in vitro LPS stimulation of purified TG or control B cells resulted in similar proliferation and IgM responses. Thus, the alteration of B cell mCD43 expression that resulted in profound immunodeficiency in vivo was not due to absolute defects in B cell development or Ab production. However, TG B cells had a decreased ability to homotypically aggregate and to present Ag to the T cell hybridoma B3Z. These data suggest that the immunodeficiency seen in vivo is due to the anti-adhesive forces of mCD43 preventing normal T-B cell interaction. This likely reflects a general property of mucins in regulating cell interactions.
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Disregulation of Leukosialin (CD43, Ly48, sialophorin) expression in the B-cell lineage of transgenic mice increases splenic B-cell number and survival.
Proceedings of the National Academy of Sciences of the United States of America, 1995Co-Authors: Leonard L. Dragone, Richard K. Barth, Kristie L. Sitar, Gary L. Disbrow, John G. FrelingerAbstract:Abstract Leukosialin (also known as Ly48, CD43, and sialophorin) is a major cell surface sialoglycoprotein found on a variety of hematopoietically derived cells. The precise function of this molecule is poorly understood but it has been implicated in cell proliferation and intercellular adhesion. We developed a transgenic mouse model to assess Leukosialin's function in vivo. Our approach was to alter mouse CD43 (mCD43) expression in the B-cell lineage where it is tightly regulated, by expressing it in peripheral B cells where it is normally absent. To drive expression of Leukosialin in mature B cells, the immunoglobulin heavy chain enhancer was fused to the mCD43 gene. mCD43-immunoglobulin heavy chain enhancer transgenic mice display splenomegaly due to increased numbers of B cells. Transgenic B cells show a striking increase in their ability to survive in vitro compared to B cells from nontransgenic control mice. This prolonged survival is reflected in a decreased susceptibility to apoptosis. These observations suggest that mCD43 plays an important role in the regulation of B-cell survival. The alteration of the temporal expression, or "disregulation," of a gene in transgenic mice provides a general strategy for elucidating the in vivo role of other molecules involved in cell signaling and adhesion.
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Thy 1+ Dendritic Epidermal Cells but not Langerhans Cells Express Ly 48
The Journal of investigative dermatology, 1993Co-Authors: Anthony A. Gaspari, Barbara Ferbel, John G. FrelingerAbstract:Leukosialin (Ly 48) is a sialoprotein expressed by bone marrow – derived cells early in their development. To determine whether Ly 48 is expressed by specific subsets of epidermal cells (ECs) such as Langerhans cells, keratinocytes, or dendritic epidermal T cells (DETCs), we utilized flow cytometry to detect staining of ECs by a panel of four monoclonal antibodies (S11, S15, S7, and 3E8) that recognize two different epitopes of the Leukosialin antigen. Approximately 2.0% of unfractionated ECs expressed Ly 48, as demonstrated by reactivity with the monoclonal antibodies St11 and S15. Similarly, immunoblots of unfractionated EC lysates revealed an antigen of 125 kD apparent molecular weight that reacted with the S11 monoclonal antibody. Enrichment or depletion of various EC populations indicated that DETCs are the only EC population that express Ly 48. Studies of long-term cultured DETC lines indicated a marked heterogeneity of expression of Ly 48 epitopes. The function(s) of Ly 48 on DETCs as well as T-cell receptor α/β bearing mouse T cells remains to be determined.
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Differential epitope expression of Ly-48 (mouse Leukosialin)
Immunogenetics, 1993Co-Authors: Clare M. Baecher-allan, Karen S. Dorfman, Richard K. Barth, John D. Kemp, John G. FrelingerAbstract:Ly-48 is a major sialoglycoprotei expressed on the surface of variety of mouse hematopoietic cells that exhibits many characteristics isoforms and may function in signal transduction and cell adhension. Ly-48 is recognized by the 3E8-specific monoclonal antibody (mAb) and it has been suggested that it is the same antigen recognized by another mAb known as S7. In this report, we demonstrate definitively by transfection of a Ly-48 cDNA that S7 and two previously uncharacterized mAbs, S11 and S15, recognize the same antigen as teh 3E8-specific mAb. However, 2-D gel immunoblot analyses demonstrate the complex nature of Ly-48. Although all four mAbs react similarly with lysates from the M-45 B-cell myeloma line, 2-D immunobot analyses of the EL-4 T-cell line reveal three distinct patterns of reactivity. Further, while transfection of Ly-48 into the K562 erythroleukemic cell line conferred reactivity to all four mAbs, transfection of the Ly-48 cDNA into the nonhematopoietic cell line, Line 1, conferred reactivity only to the S11 and S15 mAbs. Thus, the Line 1 transfectants suggest the importance of posttranslational modifications in the expression of the 3E8 and S7 epitopes. Interestingly , developing fetal liver cells show the same pattern of differential Ly-48-specific mAb reactivity. The developing early fetal liver cells are reactive with S11 and S15 but are negative, to very weakly, reactive with the 3E8-and S7-specific mAbs. These results show that Ly-48 epitopes can be expressed independently on cell lines in vitro and are differentially expressed on healthy cells in vivo.