PubMed:2708375 JSONTXT

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synthesis of thrombospondin. The role of platelets.\nMonocytes produce thrombospondin (TSP), a trimeric glycoprotein whose primary function is not yet clear. Platelet-poor monocytes (less than 1 platelet/50 monocytes) cultured with [35S]methionine produced [35S] TSP barely detectable by immunoprecipitation with either monoclonal or polyclonal antibody to TSP. Platelet-poor monocytes that had not been so thoroughly depleted of platelets (6-12 platelets/50 monocytes) synthesized readily detectable amounts of [35S] TSP. Addition of increasing numbers of washed platelets to platelet-poor monocytes resulted in increasing synthesis of [35S]TSP. This monocyte-platelet interaction was specific for cell type; neither neutrophils nor red cells could substitute for platelets. The induction of synthesis was specific for TSP; monocyte synthesis of three other proteins was not induced upon the addition of platelets. Platelet lysate or thrombin-induced platelet releasate could not substitute for intact platelets. In fact, platelet lysate inhibited [35S]TSP synthesis by monocyte-platelet cultures. This inhibition was not due to endotoxin contamination, interference with immunoprecipitation, or dilution of the [35S]methionine pool. Platelets required contact with monocytes to exert their effect, as culturing the cell populations with a filter between them prevented increased [35S]TSP synthesis. Monocyte-platelet interactions may serve to specifically increase monocyte synthesis of the adhesive protein, TSP."}

{"project":"sentences","denotations":[{"id":"T1","span":{"begin":0,"end":37},"obj":"Sentence"},{"id":"T2","span":{"begin":38,"end":60},"obj":"Sentence"},{"id":"T3","span":{"begin":61,"end":165},"obj":"Sentence"},{"id":"T4","span":{"begin":166,"end":369},"obj":"Sentence"},{"id":"T5","span":{"begin":370,"end":530},"obj":"Sentence"},{"id":"T6","span":{"begin":531,"end":654},"obj":"Sentence"},{"id":"T7","span":{"begin":655,"end":783},"obj":"Sentence"},{"id":"T8","span":{"begin":784,"end":923},"obj":"Sentence"},{"id":"T9","span":{"begin":924,"end":1021},"obj":"Sentence"},{"id":"T10","span":{"begin":1022,"end":1106},"obj":"Sentence"},{"id":"T11","span":{"begin":1107,"end":1242},"obj":"Sentence"},{"id":"T12","span":{"begin":1243,"end":1408},"obj":"Sentence"},{"id":"T13","span":{"begin":1409,"end":1523},"obj":"Sentence"},{"id":"T1","span":{"begin":0,"end":37},"obj":"Sentence"},{"id":"T2","span":{"begin":38,"end":60},"obj":"Sentence"},{"id":"T3","span":{"begin":61,"end":165},"obj":"Sentence"},{"id":"T4","span":{"begin":166,"end":369},"obj":"Sentence"},{"id":"T5","span":{"begin":370,"end":530},"obj":"Sentence"},{"id":"T6","span":{"begin":531,"end":654},"obj":"Sentence"},{"id":"T7","span":{"begin":655,"end":783},"obj":"Sentence"},{"id":"T8","span":{"begin":784,"end":923},"obj":"Sentence"},{"id":"T9","span":{"begin":924,"end":1021},"obj":"Sentence"},{"id":"T10","span":{"begin":1022,"end":1106},"obj":"Sentence"},{"id":"T11","span":{"begin":1107,"end":1242},"obj":"Sentence"},{"id":"T12","span":{"begin":1243,"end":1408},"obj":"Sentence"},{"id":"T13","span":{"begin":1409,"end":1523},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"Monocyte synthesis of thrombospondin. The role of platelets.\nMonocytes produce thrombospondin (TSP), a trimeric glycoprotein whose primary function is not yet clear. Platelet-poor monocytes (less than 1 platelet/50 monocytes) cultured with [35S]methionine produced [35S] TSP barely detectable by immunoprecipitation with either monoclonal or polyclonal antibody to TSP. Platelet-poor monocytes that had not been so thoroughly depleted of platelets (6-12 platelets/50 monocytes) synthesized readily detectable amounts of [35S] TSP. Addition of increasing numbers of washed platelets to platelet-poor monocytes resulted in increasing synthesis of [35S]TSP. This monocyte-platelet interaction was specific for cell type; neither neutrophils nor red cells could substitute for platelets. The induction of synthesis was specific for TSP; monocyte synthesis of three other proteins was not induced upon the addition of platelets. Platelet lysate or thrombin-induced platelet releasate could not substitute for intact platelets. In fact, platelet lysate inhibited [35S]TSP synthesis by monocyte-platelet cultures. This inhibition was not due to endotoxin contamination, interference with immunoprecipitation, or dilution of the [35S]methionine pool. Platelets required contact with monocytes to exert their effect, as culturing the cell populations with a filter between them prevented increased [35S]TSP synthesis. Monocyte-platelet interactions may serve to specifically increase monocyte synthesis of the adhesive protein, TSP."}

{"project":"mondo_disease","denotations":[{"id":"T1","span":{"begin":95,"end":98},"obj":"Disease"},{"id":"T2","span":{"begin":271,"end":274},"obj":"Disease"},{"id":"T3","span":{"begin":365,"end":368},"obj":"Disease"},{"id":"T4","span":{"begin":526,"end":529},"obj":"Disease"},{"id":"T5","span":{"begin":650,"end":653},"obj":"Disease"},{"id":"T6","span":{"begin":828,"end":831},"obj":"Disease"},{"id":"T7","span":{"begin":1062,"end":1065},"obj":"Disease"},{"id":"T8","span":{"begin":1394,"end":1397},"obj":"Disease"},{"id":"T9","span":{"begin":1519,"end":1522},"obj":"Disease"}],"attributes":[{"id":"A1","pred":"mondo_id","subj":"T1","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A2","pred":"mondo_id","subj":"T2","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A3","pred":"mondo_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A4","pred":"mondo_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A5","pred":"mondo_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A6","pred":"mondo_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A7","pred":"mondo_id","subj":"T7","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A8","pred":"mondo_id","subj":"T8","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"},{"id":"A9","pred":"mondo_id","subj":"T9","obj":"http://purl.obolibrary.org/obo/MONDO_0008039"}],"text":"Monocyte synthesis of thrombospondin. The role of platelets.\nMonocytes produce thrombospondin (TSP), a trimeric glycoprotein whose primary function is not yet clear. Platelet-poor monocytes (less than 1 platelet/50 monocytes) cultured with [35S]methionine produced [35S] TSP barely detectable by immunoprecipitation with either monoclonal or polyclonal antibody to TSP. Platelet-poor monocytes that had not been so thoroughly depleted of platelets (6-12 platelets/50 monocytes) synthesized readily detectable amounts of [35S] TSP. Addition of increasing numbers of washed platelets to platelet-poor monocytes resulted in increasing synthesis of [35S]TSP. This monocyte-platelet interaction was specific for cell type; neither neutrophils nor red cells could substitute for platelets. The induction of synthesis was specific for TSP; monocyte synthesis of three other proteins was not induced upon the addition of platelets. Platelet lysate or thrombin-induced platelet releasate could not substitute for intact platelets. In fact, platelet lysate inhibited [35S]TSP synthesis by monocyte-platelet cultures. This inhibition was not due to endotoxin contamination, interference with immunoprecipitation, or dilution of the [35S]methionine pool. Platelets required contact with monocytes to exert their effect, as culturing the cell populations with a filter between them prevented increased [35S]TSP synthesis. Monocyte-platelet interactions may serve to specifically increase monocyte synthesis of the adhesive protein, TSP."}

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synthesis of thrombospondin. The role of platelets.\nMonocytes produce thrombospondin (TSP), a trimeric glycoprotein whose primary function is not yet clear. Platelet-poor monocytes (less than 1 platelet/50 monocytes) cultured with [35S]methionine produced [35S] TSP barely detectable by immunoprecipitation with either monoclonal or polyclonal antibody to TSP. Platelet-poor monocytes that had not been so thoroughly depleted of platelets (6-12 platelets/50 monocytes) synthesized readily detectable amounts of [35S] TSP. Addition of increasing numbers of washed platelets to platelet-poor monocytes resulted in increasing synthesis of [35S]TSP. This monocyte-platelet interaction was specific for cell type; neither neutrophils nor red cells could substitute for platelets. The induction of synthesis was specific for TSP; monocyte synthesis of three other proteins was not induced upon the addition of platelets. Platelet lysate or thrombin-induced platelet releasate could not substitute for intact platelets. In fact, platelet lysate inhibited [35S]TSP synthesis by monocyte-platelet cultures. This inhibition was not due to endotoxin contamination, interference with immunoprecipitation, or dilution of the [35S]methionine pool. Platelets required contact with monocytes to exert their effect, as culturing the cell populations with a filter between them prevented increased [35S]TSP synthesis. Monocyte-platelet interactions may serve to specifically increase monocyte synthesis of the adhesive protein, TSP."}