OBJECTIVE: To evaluate the role of thrombopoietin (TPO) in the pathology of chronic thrombocytopenic disease. METHODS: We measured the endogenous plasma concentration of TPO in 40 patients with acquired aplastic anaem...OBJECTIVE: To evaluate the role of thrombopoietin (TPO) in the pathology of chronic thrombocytopenic disease. METHODS: We measured the endogenous plasma concentration of TPO in 40 patients with acquired aplastic anaemia (AA) and in 32 patients with idiopathic thrombocytopenic purpura (ITP) by a sensitive Sandwich enzyme-linked immunosorbent assay (ELISA) and compared the results. RESULTS: Plasma TPO concentrations were significantly higher in AA patients (774 +/- 393 pg/ ml) in comparison with healthy control subjects (55 +/- 34 pg/ml, P 0.05). There was also no relationship between their plasma TPO levels and platelet counts. CONCLUSIONS: TPO levels may be regulated not only by platelets but also by megakaryocytes in AA and ITP, and measurement of TPO levels is useful for diagnosing thrombocytopenia and understanding the pathophysiology of thrombocytopenia.展开更多
Hemophilia A is caused by a genetic mutation in coagulation factor VIII （FVIII） gene and gene therapy is considered to be a promising strategy for its treatment. We recently demonstrated that co-delivery of two vect...Hemophilia A is caused by a genetic mutation in coagulation factor VIII （FVIII） gene and gene therapy is considered to be a promising strategy for its treatment. We recently demonstrated that co-delivery of two vectors expressing M662C mutated heavy and D1828C mutated light chain genes of B-domain-deleted coagulation factor VIII （BDD-FVIII） leads to inter-chain disulfide cross-linking and improved heavy chain secretion in vitro. In this study, co-injection of both M662C and D1828C mutated BDD-FVIII gene expression vectors into mice resulted in increased heavy chain secretion and coagulation activity in plasma in vivo. Approximately （239＋_56） ng mL-1 above endogenous levels of transgenic FVIII heavy chain was found in mouse plasma using a chain-specific ELISA. For FVIII coagulation activity, approximately （1.09＋_0.25） IU mL-1 above en- dogenous levels were detected in co-injected transgenic mouse plasma using a chromogenic assay. These data demonstrate that inter-chain disulfide bonds likely increase heavy chain secretion and coagulation activity in the plasma of transgenic mice with an improved efficacy of a dual-vector delivery of BDD-FVIII gene. These findings support our ongoing efforts to develop a gene therapy for hemophilia A treatment using dual-AAV vectors.展开更多
文摘OBJECTIVE: To evaluate the role of thrombopoietin (TPO) in the pathology of chronic thrombocytopenic disease. METHODS: We measured the endogenous plasma concentration of TPO in 40 patients with acquired aplastic anaemia (AA) and in 32 patients with idiopathic thrombocytopenic purpura (ITP) by a sensitive Sandwich enzyme-linked immunosorbent assay (ELISA) and compared the results. RESULTS: Plasma TPO concentrations were significantly higher in AA patients (774 +/- 393 pg/ ml) in comparison with healthy control subjects (55 +/- 34 pg/ml, P 0.05). There was also no relationship between their plasma TPO levels and platelet counts. CONCLUSIONS: TPO levels may be regulated not only by platelets but also by megakaryocytes in AA and ITP, and measurement of TPO levels is useful for diagnosing thrombocytopenia and understanding the pathophysiology of thrombocytopenia.
基金supported by the Natural Science Foundation of Shandong Province,China(Grant No.ZR2010CM061)the Scientific Research Foundation from Ministry of Education for Returned Overseas Chinese Scholars(Grant No.20071108)
文摘Hemophilia A is caused by a genetic mutation in coagulation factor VIII （FVIII） gene and gene therapy is considered to be a promising strategy for its treatment. We recently demonstrated that co-delivery of two vectors expressing M662C mutated heavy and D1828C mutated light chain genes of B-domain-deleted coagulation factor VIII （BDD-FVIII） leads to inter-chain disulfide cross-linking and improved heavy chain secretion in vitro. In this study, co-injection of both M662C and D1828C mutated BDD-FVIII gene expression vectors into mice resulted in increased heavy chain secretion and coagulation activity in plasma in vivo. Approximately （239＋_56） ng mL-1 above endogenous levels of transgenic FVIII heavy chain was found in mouse plasma using a chain-specific ELISA. For FVIII coagulation activity, approximately （1.09＋_0.25） IU mL-1 above en- dogenous levels were detected in co-injected transgenic mouse plasma using a chromogenic assay. These data demonstrate that inter-chain disulfide bonds likely increase heavy chain secretion and coagulation activity in the plasma of transgenic mice with an improved efficacy of a dual-vector delivery of BDD-FVIII gene. These findings support our ongoing efforts to develop a gene therapy for hemophilia A treatment using dual-AAV vectors.
