PubMed:21835922 JSONTXT

{"project":"GlyCosmos6-Glycan-Motif-Image","denotations":[{"id":"T1","span":{"begin":84,"end":108},"obj":"Glycan_Motif"},{"id":"T3","span":{"begin":311,"end":322},"obj":"Glycan_Motif"},{"id":"T4","span":{"begin":933,"end":944},"obj":"Glycan_Motif"},{"id":"T5","span":{"begin":1036,"end":1060},"obj":"Glycan_Motif"},{"id":"T7","span":{"begin":1062,"end":1067},"obj":"Glycan_Motif"},{"id":"T8","span":{"begin":1283,"end":1288},"obj":"Glycan_Motif"},{"id":"T9","span":{"begin":1322,"end":1327},"obj":"Glycan_Motif"},{"id":"T10","span":{"begin":1452,"end":1457},"obj":"Glycan_Motif"},{"id":"T11","span":{"begin":1719,"end":1724},"obj":"Glycan_Motif"}],"attributes":[{"id":"A1","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A2","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G50850NI"},{"id":"A3","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A4","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A5","pred":"image","subj":"T5","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A6","pred":"image","subj":"T5","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G50850NI"},{"id":"A7","pred":"image","subj":"T7","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A8","pred":"image","subj":"T8","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A9","pred":"image","subj":"T9","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A10","pred":"image","subj":"T10","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"},{"id":"A11","pred":"image","subj":"T11","obj":"https://api.glycosmos.org/wurcs2image/0.10.0/png/binary/G81533KY"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"sentences","denotations":[{"id":"T1","span":{"begin":0,"end":148},"obj":"Sentence"},{"id":"T2","span":{"begin":149,"end":369},"obj":"Sentence"},{"id":"T3","span":{"begin":370,"end":467},"obj":"Sentence"},{"id":"T4","span":{"begin":468,"end":693},"obj":"Sentence"},{"id":"T5","span":{"begin":694,"end":906},"obj":"Sentence"},{"id":"T6","span":{"begin":907,"end":1120},"obj":"Sentence"},{"id":"T7","span":{"begin":1121,"end":1359},"obj":"Sentence"},{"id":"T8","span":{"begin":1360,"end":1600},"obj":"Sentence"},{"id":"T9","span":{"begin":1601,"end":1784},"obj":"Sentence"},{"id":"T10","span":{"begin":1785,"end":2003},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"GlyCosmos6-Glycan-Motif-Structure","denotations":[{"id":"T1","span":{"begin":84,"end":108},"obj":"https://glytoucan.org/Structures/Glycans/G50850NI"},{"id":"T2","span":{"begin":84,"end":108},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T3","span":{"begin":311,"end":322},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T4","span":{"begin":933,"end":944},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"},{"id":"T5","span":{"begin":1036,"end":1060},"obj":"https://glytoucan.org/Structures/Glycans/G50850NI"},{"id":"T6","span":{"begin":1036,"end":1060},"obj":"https://glytoucan.org/Structures/Glycans/G81533KY"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"Glycan-GlyCosmos","denotations":[{"id":"T1","span":{"begin":1062,"end":1067},"obj":"Glycan"},{"id":"T2","span":{"begin":1283,"end":1288},"obj":"Glycan"},{"id":"T3","span":{"begin":1322,"end":1327},"obj":"Glycan"},{"id":"T4","span":{"begin":1452,"end":1457},"obj":"Glycan"},{"id":"T5","span":{"begin":1719,"end":1724},"obj":"Glycan"}],"attributes":[{"id":"A1","pred":"glycosmos_id","subj":"T1","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A6","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A2","pred":"glycosmos_id","subj":"T2","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A7","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A3","pred":"glycosmos_id","subj":"T3","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A8","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A4","pred":"glycosmos_id","subj":"T4","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A9","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A5","pred":"glycosmos_id","subj":"T5","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A10","pred":"image","subj":"T5","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"Allie","denotations":[{"id":"SS1_21835922_5_0","span":{"begin":1036,"end":1060},"obj":"expanded"},{"id":"SS2_21835922_5_0","span":{"begin":1062,"end":1067},"obj":"abbr"},{"id":"SS1_21835922_5_1","span":{"begin":1072,"end":1098},"obj":"expanded"},{"id":"SS2_21835922_5_1","span":{"begin":1100,"end":1105},"obj":"abbr"}],"relations":[{"id":"AE1_21835922_5_0","pred":"abbreviatedTo","subj":"SS1_21835922_5_0","obj":"SS2_21835922_5_0"},{"id":"AE1_21835922_5_1","pred":"abbreviatedTo","subj":"SS1_21835922_5_1","obj":"SS2_21835922_5_1"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"GlyCosmos15-NCBITAXON","denotations":[{"id":"T1","span":{"begin":842,"end":859},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":880,"end":894},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"37501"},{"id":"A2","pred":"db_id","subj":"T2","obj":"4202"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"GlyCosmos15-CL","denotations":[{"id":"T1","span":{"begin":13,"end":25},"obj":"Cell"},{"id":"T2","span":{"begin":15,"end":25},"obj":"Cell"},{"id":"T3","span":{"begin":184,"end":196},"obj":"Cell"},{"id":"T4","span":{"begin":186,"end":196},"obj":"Cell"},{"id":"T5","span":{"begin":445,"end":458},"obj":"Cell"},{"id":"T6","span":{"begin":629,"end":641},"obj":"Cell"},{"id":"T7","span":{"begin":677,"end":692},"obj":"Cell"},{"id":"T9","span":{"begin":728,"end":734},"obj":"Cell"},{"id":"T10","span":{"begin":985,"end":998},"obj":"Cell"},{"id":"T11","span":{"begin":1173,"end":1180},"obj":"Cell"},{"id":"T12","span":{"begin":1586,"end":1599},"obj":"Cell"},{"id":"T13","span":{"begin":1648,"end":1654},"obj":"Cell"},{"id":"T14","span":{"begin":1935,"end":1948},"obj":"Cell"},{"id":"T15","span":{"begin":1953,"end":1966},"obj":"Cell"}],"attributes":[{"id":"A1","pred":"cl_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A2","pred":"cl_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/CL:0000542"},{"id":"A3","pred":"cl_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A4","pred":"cl_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/CL:0000542"},{"id":"A5","pred":"cl_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A6","pred":"cl_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/CL:0000763"},{"id":"A7","pred":"cl_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/CL:0000451"},{"id":"A8","pred":"cl_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/CL:0001056"},{"id":"A9","pred":"cl_id","subj":"T9","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A10","pred":"cl_id","subj":"T10","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A11","pred":"cl_id","subj":"T11","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A12","pred":"cl_id","subj":"T12","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A13","pred":"cl_id","subj":"T13","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A14","pred":"cl_id","subj":"T14","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A15","pred":"cl_id","subj":"T15","obj":"http://purl.obolibrary.org/obo/CL:0000763"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"GlyCosmos15-UBERON","denotations":[{"id":"T1","span":{"begin":13,"end":25},"obj":"Body_part"},{"id":"T2","span":{"begin":184,"end":196},"obj":"Body_part"},{"id":"T3","span":{"begin":445,"end":458},"obj":"Body_part"},{"id":"T4","span":{"begin":629,"end":641},"obj":"Body_part"},{"id":"T5","span":{"begin":677,"end":692},"obj":"Body_part"},{"id":"T6","span":{"begin":728,"end":734},"obj":"Body_part"},{"id":"T7","span":{"begin":985,"end":998},"obj":"Body_part"},{"id":"T8","span":{"begin":1586,"end":1599},"obj":"Body_part"},{"id":"T9","span":{"begin":1648,"end":1654},"obj":"Body_part"},{"id":"T10","span":{"begin":1935,"end":1948},"obj":"Body_part"},{"id":"T11","span":{"begin":1953,"end":1966},"obj":"Body_part"}],"attributes":[{"id":"A1","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A2","pred":"uberon_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A3","pred":"uberon_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A4","pred":"uberon_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/CL_0000763"},{"id":"A5","pred":"uberon_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/CL_0000451"},{"id":"A6","pred":"uberon_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A7","pred":"uberon_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A8","pred":"uberon_id","subj":"T8","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A9","pred":"uberon_id","subj":"T9","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A10","pred":"uberon_id","subj":"T10","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A11","pred":"uberon_id","subj":"T11","obj":"http://purl.obolibrary.org/obo/CL_0000763"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"sentences","denotations":[{"id":"T1","span":{"begin":0,"end":148},"obj":"Sentence"},{"id":"T2","span":{"begin":149,"end":369},"obj":"Sentence"},{"id":"T3","span":{"begin":370,"end":467},"obj":"Sentence"},{"id":"T4","span":{"begin":468,"end":693},"obj":"Sentence"},{"id":"T5","span":{"begin":694,"end":906},"obj":"Sentence"},{"id":"T6","span":{"begin":907,"end":1120},"obj":"Sentence"},{"id":"T7","span":{"begin":1121,"end":1359},"obj":"Sentence"},{"id":"T8","span":{"begin":1360,"end":1600},"obj":"Sentence"},{"id":"T9","span":{"begin":1601,"end":1784},"obj":"Sentence"},{"id":"T10","span":{"begin":1785,"end":2003},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"GlyCosmos15-Sentences","blocks":[{"id":"T1","span":{"begin":0,"end":148},"obj":"Sentence"},{"id":"T2","span":{"begin":149,"end":369},"obj":"Sentence"},{"id":"T3","span":{"begin":370,"end":467},"obj":"Sentence"},{"id":"T4","span":{"begin":468,"end":693},"obj":"Sentence"},{"id":"T5","span":{"begin":694,"end":906},"obj":"Sentence"},{"id":"T6","span":{"begin":907,"end":1120},"obj":"Sentence"},{"id":"T7","span":{"begin":1121,"end":1359},"obj":"Sentence"},{"id":"T8","span":{"begin":1360,"end":1600},"obj":"Sentence"},{"id":"T9","span":{"begin":1601,"end":1784},"obj":"Sentence"},{"id":"T10","span":{"begin":1785,"end":2003},"obj":"Sentence"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"GlyCosmos15-Glycan","denotations":[{"id":"T1","span":{"begin":1062,"end":1067},"obj":"Glycan"},{"id":"T2","span":{"begin":1283,"end":1288},"obj":"Glycan"},{"id":"T3","span":{"begin":1322,"end":1327},"obj":"Glycan"},{"id":"T4","span":{"begin":1452,"end":1457},"obj":"Glycan"},{"id":"T5","span":{"begin":1719,"end":1724},"obj":"Glycan"}],"attributes":[{"id":"A1","pred":"glycosmos_id","subj":"T1","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A6","pred":"image","subj":"T1","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A2","pred":"glycosmos_id","subj":"T2","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A7","pred":"image","subj":"T2","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A3","pred":"glycosmos_id","subj":"T3","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A8","pred":"image","subj":"T3","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A4","pred":"glycosmos_id","subj":"T4","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A9","pred":"image","subj":"T4","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"},{"id":"A5","pred":"glycosmos_id","subj":"T5","obj":"https://glycosmos.org/glycans/show/G76685HR"},{"id":"A10","pred":"image","subj":"T5","obj":"https://api.glycosmos.org/wurcs2image/latest/png/binary/G76685HR"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"Lectin-Jamboree-Sentence","blocks":[{"id":"T1","span":{"begin":0,"end":148},"obj":"Sentence"},{"id":"T2","span":{"begin":149,"end":369},"obj":"Sentence"},{"id":"T3","span":{"begin":370,"end":467},"obj":"Sentence"},{"id":"T4","span":{"begin":468,"end":693},"obj":"Sentence"},{"id":"T5","span":{"begin":694,"end":906},"obj":"Sentence"},{"id":"T6","span":{"begin":907,"end":1120},"obj":"Sentence"},{"id":"T7","span":{"begin":1121,"end":1359},"obj":"Sentence"},{"id":"T8","span":{"begin":1360,"end":1600},"obj":"Sentence"},{"id":"T9","span":{"begin":1601,"end":1784},"obj":"Sentence"},{"id":"T10","span":{"begin":1785,"end":2003},"obj":"Sentence"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"NCBITAXON","denotations":[{"id":"T1","span":{"begin":842,"end":859},"obj":"OrganismTaxon"},{"id":"T2","span":{"begin":880,"end":894},"obj":"OrganismTaxon"}],"attributes":[{"id":"A1","pred":"db_id","subj":"T1","obj":"37501"},{"id":"A2","pred":"db_id","subj":"T2","obj":"4202"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"Anatomy-UBERON","denotations":[{"id":"T1","span":{"begin":13,"end":25},"obj":"Body_part"},{"id":"T2","span":{"begin":184,"end":196},"obj":"Body_part"},{"id":"T3","span":{"begin":445,"end":458},"obj":"Body_part"},{"id":"T4","span":{"begin":629,"end":641},"obj":"Body_part"},{"id":"T5","span":{"begin":677,"end":692},"obj":"Body_part"},{"id":"T6","span":{"begin":728,"end":734},"obj":"Body_part"},{"id":"T7","span":{"begin":985,"end":998},"obj":"Body_part"},{"id":"T8","span":{"begin":1586,"end":1599},"obj":"Body_part"},{"id":"T9","span":{"begin":1648,"end":1654},"obj":"Body_part"},{"id":"T10","span":{"begin":1935,"end":1948},"obj":"Body_part"},{"id":"T11","span":{"begin":1953,"end":1966},"obj":"Body_part"}],"attributes":[{"id":"A1","pred":"uberon_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A2","pred":"uberon_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A3","pred":"uberon_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A4","pred":"uberon_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/CL_0000763"},{"id":"A5","pred":"uberon_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/CL_0000451"},{"id":"A6","pred":"uberon_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A7","pred":"uberon_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A8","pred":"uberon_id","subj":"T8","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A9","pred":"uberon_id","subj":"T9","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A10","pred":"uberon_id","subj":"T10","obj":"http://purl.obolibrary.org/obo/CL_0000084"},{"id":"A11","pred":"uberon_id","subj":"T11","obj":"http://purl.obolibrary.org/obo/CL_0000763"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}

{"project":"CL-cell","denotations":[{"id":"T1","span":{"begin":13,"end":25},"obj":"Cell"},{"id":"T2","span":{"begin":15,"end":25},"obj":"Cell"},{"id":"T3","span":{"begin":184,"end":196},"obj":"Cell"},{"id":"T4","span":{"begin":186,"end":196},"obj":"Cell"},{"id":"T5","span":{"begin":445,"end":458},"obj":"Cell"},{"id":"T6","span":{"begin":629,"end":641},"obj":"Cell"},{"id":"T7","span":{"begin":677,"end":692},"obj":"Cell"},{"id":"T9","span":{"begin":728,"end":734},"obj":"Cell"},{"id":"T10","span":{"begin":985,"end":998},"obj":"Cell"},{"id":"T11","span":{"begin":1173,"end":1180},"obj":"Cell"},{"id":"T12","span":{"begin":1586,"end":1599},"obj":"Cell"},{"id":"T13","span":{"begin":1648,"end":1654},"obj":"Cell"},{"id":"T14","span":{"begin":1935,"end":1948},"obj":"Cell"},{"id":"T15","span":{"begin":1953,"end":1966},"obj":"Cell"}],"attributes":[{"id":"A1","pred":"cl_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A2","pred":"cl_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/CL:0000542"},{"id":"A3","pred":"cl_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A4","pred":"cl_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/CL:0000542"},{"id":"A5","pred":"cl_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A6","pred":"cl_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/CL:0000763"},{"id":"A7","pred":"cl_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/CL:0000451"},{"id":"A8","pred":"cl_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/CL:0001056"},{"id":"A9","pred":"cl_id","subj":"T9","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A10","pred":"cl_id","subj":"T10","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A11","pred":"cl_id","subj":"T11","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A12","pred":"cl_id","subj":"T12","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A13","pred":"cl_id","subj":"T13","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A14","pred":"cl_id","subj":"T14","obj":"http://purl.obolibrary.org/obo/CL:0000084"},{"id":"A15","pred":"cl_id","subj":"T15","obj":"http://purl.obolibrary.org/obo/CL:0000763"}],"text":"Early murine T-lymphocyte activation is accompanied by a switch from N-Glycolyl- to N-acetyl-neuraminic acid and generation of ligands for siglec-E.\nIt is well established that murine T-lymphocyte activation is accompanied by major changes in cell-surface sialylation, potentially influencing interactions with sialic acid-binding immunoglobulin-like lectins (siglecs). In the present study, we analyzed early activation of murine CD4+ and CD8+ T-lymphocytes at 24 h. We observed a striking and selective up-regulation in the binding of a recombinant soluble form of siglec-E, an inhibitory siglec, which is expressed on several myeloid cell types including antigen-presenting dendritic cells. In contrast, much lower levels of T cell binding were observed with other siglecs, including sialoadhesin, CD22, and siglec-F and the plant lectins Maackia amurensis leukoagglutinin and Sambucus nigra agglutinin. By mass spectrometry, the sialic acid content of 24-h-activated CD4+ and CD8+ T-lymphocytes exhibited an increased proportion of N-acetyl-neuraminic acid (NeuAc) to N-glycolyl-neuraminic acid (NeuGc) in N-glycans. Reduced levels of NeuGc on the surface of activated T cells were demonstrated using an antibody specific for NeuGc and the expression levels of the gene encoding NeuAc- to NeuGc-converting enzyme, CMP-NeuAc hydroxylase, were also reduced. Siglec-E bound a wide range of sialylated structures in glycan arrays, had a preference for NeuAc versus NeuGc-terminated sequences and could recognize a set of sialoglycoproteins that included CD45, in lysates from activated T-lymphocytes. Collectively, these results show that early in T cell activation, glycan remodelling involves a switch from NeuGc- to NeuAc-terminating oligosaccharides on cell surface glycoproteins. This is associated with a strong up-regulation of siglec-E ligands, which may be important in promoting cellular interactions between early activated T-lymphocytes and myeloid cells expressing this inhibitory receptor."}