| 1. |
- Andersson, Ellen, et al.
(författare)
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Treatment with anti-factor VIIa in acute pancreatitis in rats: Blocking both coagulation and inflammation?
- 2007
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Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 1502-7708 .- 0036-5521. ; 42:6, s. 765-770
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Tidskriftsartikel (refereegranskat)abstract
- Objective. Acute pancreatitis starts as an autodigestive process restricted to the pancreas and progresses to a systemic inflammation via cytokine release into the blood stream. Several inhibitors of the coagulation cascade, including active- siteinactivated factor VIIa, have shown anti- inflammatory properties in other inflammatory models than acute pancreatitis. Free radical scavengers have proven useful in reducing the oxidative damage during hyperinflammatory conditions. The aim of this study was to investigate whether pretreatment with FVIIai would have any effect on the multiple organ dysfunction syndrome ( MODS) in severe acute pancreatitis. Material and methods. Experimental acute pancreatitis was induced by intraductal infusion of taurodeoxycholate in the pancreatic duct. The animals were pretreated with N- acetyl- cysteine and active- site- inactivated factor VIIa. Neutrophil infiltration in the lungs, ileum and colon was quantified by myeloperoxidase activity. Inflammatory markers, IL- 6 and MIP- 2, were measured using ELISA. Results. Tissue infiltration of neutrophils in the lungs, ileum and colon significantly increased during acute pancreatitis as compared to sham operation. These levels were reduced by pretreatment with N- acetylcysteine and active- site- inactivated factor VIIa. Levels of interleukin- 6 and macrophage inflammatory protein- 2 increased significantly during acute pancreatitis. Pretreatment with NAC and FVIIai reduced these levels. Conclusions. Both N- acetylcysteine and active- site- inactivated factor VIIa showed powerful antiinflammatory properties in experimental acute pancreatitis. As they exert their effects through different physiological mechanisms, they represent potential candidates for future multimodal treatment of acute pancreatitis.
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| 2. |
- Ostergaard, Henrik, et al.
(författare)
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Prolonged half-life and preserved enzymatic properties of factor IX selectively PEGylated on native N-glycans in the activation peptide
- 2011
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 118:8, s. 2333-2341
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Tidskriftsartikel (refereegranskat)abstract
- Current management of hemophilia B entails multiple weekly infusions of factor IX (FIX) to prevent bleeding episodes. In an attempt to make a longer acting recombinant FIX (rFIX), we have explored a new releasable protraction concept using the native N-glycans in the activation peptide as sites for attachment of polyethylene glycol (PEG). Release of the activation peptide by physiologic activators converted glycoPEGylated rFIX (N9-GP) to native rFIXa and proceeded with normal kinetics for FXIa, while the Km for activation by FVIIa-tissue factor (TF) was increased by 2-fold. Consistent with minimal perturbation of rFIX by the attached PEG, N9-GP retained 73%-100% specific activity in plasma and whole-blood-based assays and showed efficacy comparable with rFIX in stopping acute bleeds in hemophilia B mice. In animal models N9-GP exhibited up to 2-fold increased in vivo recovery and a markedly prolonged half-life in mini-pig (76 hours) and hemophilia B dog (113 hours) compared with rFIX (16 hours). The extended circulation time of N9-GP was reflected in prolonged correction of coagulation parameters in hemophilia B dog and duration of effect in hemophilia B mice. Collectively, these results suggest that N9-GP has the potential to offer efficacious prophylactic and acute treatment of hemophilia B patients at a reduced dosing frequency. (Blood. 2011; 118(8): 2333-2341)
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