|
|||||||||
|
|
|
|
|
|
|
|
|
|
|
HEMOSTASIS, THROMBOSIS, AND VASCULAR BIOLOGY
From the Winship Cancer Institute, Emory University,
Atlanta, GA.
Fulminant hepatic failure (FHF) in humans produces a bleeding
diathesis due in large part to a reduction in the biosynthesis of
liver-derived coagulation factors. Remarkably, factor VIII procoagulant
activity is elevated in most of these patients despite widespread liver
cell death. FHF can be modeled in mice by administration of
azoxymethane, the active ingredient found in cycad palm nuts. We
compared the expression of factor VIII to other hepatic hemostatic factors in azoxymethane-induced murine FHF. Mice displayed
dose-dependent decreases in all coagulation factor activities measured,
including factors V, VII, VIII, and IX. At the highest dose of
azoxymethane (50 µg/g body weight), factor VIII activity in plasma
decreased by 98% within 36 hours after treatment, which was associated
with an 80% reduction in hepatic factor VIII messenger RNA (mRNA). In
contrast, factor VIII mRNA levels in spleen, kidney, and lung tissue of
azoxymethane-treated mice were unchanged. Cellular damage in these mice
appeared to be limited to hepatocytes as evident by histologic
examination. This finding is supported by 2 observations. First,
hepatic mRNA levels of von Willebrand factor, which is synthesized by
liver sinusoidal endothelial cells but not hepatocytes, were unchanged.
Second, von Willebrand factor was detected antigenically in liver
sections of azoxymethane-treated mice by immunofluorescence. These
results indicate that the contribution of the liver to factor VIII
biosynthesis is not replaced or significantly supplemented by other
tissues in this model of FHF.
(Blood. 2002;100:143-147) Despite more than 50 years of investigation,
the nature of factor VIII biosynthesis in vivo remains poorly
understood.1-4 Factor VIII messenger RNA (mRNA) is present
in nearly every tissue examined, including liver, spleen, lymph node,
heart, brain, lung, kidney, testes, muscle, and
placenta.5-7 The liver clearly is an important site of
synthesis because liver transplantation cures human and canine
hemophilia A.8-10 However, the relative contribution of
hepatocytes and liver sinusoidal endothelial cells remains uncertain.7,11-15 Furthermore, the contribution of
extrahepatic biosynthesis of factor VIII in health and disease states
is not known.
Paradoxically, there usually is a significant rise in plasma
factor VIII activity in human fulminant hepatic failure
(FHF).16-19 This increase can be more than 14 times normal
levels and occurs simultaneously with profound decreases in the
circulating levels of vitamin K-dependent and fibrinolytic plasma
proteins.16,20,21 The analysis of this phenomenon has been
hindered by the lack of a reproducible animal model of FHF. However, a
murine model of FHF recently was developed using the hepatotoxin
azoxymethane (AOM), which is found in cycad palm nuts on the island of
Guam.22 AOM-treated mice develop hepatocellular necrosis,
elevated liver transaminase and ammonia levels in blood and hepatic
encephalopathy. They die within days, with death related to the dose of
AOM. In this study, we examined the expression of factor VIII
and several other hemostatic factors, including factors V, VII, and IX,
and von Willebrand factor (VWF) in AOM-induced murine FHF.
Materials
Animal care and maintenance
Histology and immunohistochemistry Organs designated for histology were harvested and immediately placed in 10% neutral phosphate-buffered formalin (Fisher Scientific, Pittsburgh, PA) and incubated at 4°C overnight for fixation. Tissue processing and sectioning were performed by the Department of Animal Resources at Emory University. Tissue sections 5 to 6 µm thick were stained with hematoxylin and eosin and visualized by light microscopy.Portions of livers designated for immunofluorescence were harvested and
immediately placed in liquid nitrogen for 1 to 2 minutes. Tissue-Tek
OCT (Sakura, Torrance, CA) was applied to tissues prior to sectioning.
Sections 6 µm thick were cut at Coagulation factor assays Clotting assays were performed using a ST art 4 BIO Coagulation Instrument (Diagnostica Stago). For factor V and factor VII assays, 50 µL factor V- or factor VII-deficient plasma and 5 µL citrated mouse plasma were dispensed into a prewarmed cuvette at 37°C. After a 60-second incubation, 100 µL neoplastine was added and the clotting time was measured. For assays of factors VIII and IX, 50 µL factor VIII- or factor IX-deficient plasma, 5 µL citrated mouse plasma, and 50 µL aPTT were dispensed into a prewarmed cuvette at 37°C. After a 180-second incubation, 50 µL 0.02 M CaCl2 was added to initiate the clotting time. Clotting times were compared to a standard curve prepared using pooled normal human plasma using linear regression analysis of clotting time versus the logarithm of activity. The coagulation factor activities stated by the manufacturer of the standard plasma were used. The activities of factors V, VII, VIII, and IX in plasmas of mice obtained 72 hours after injection of control saline were 11.1 ± 2.1, 4.65 ± 0.73, 3.09 ± 0.89, and 0.93 ± 0.16 U/mL (mean ± sample SD), respectively.RNA analysis Tissues for RNA analysis were harvested, immediately placed in RNAlater (Ambion, Austin, TX), and stored at 4°C until use. RNA extraction was performed using TriReagent following the manufacturer's protocol. RNA integrity was confirmed by an A260/A280 ratio of more than 1.7 and ethidium bromide visualization following agarose gel electrophoresis. Competitive reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed as described previously11 with the following changes. Factor VIII competitor complementary (RNA) was constructed by PCR amplification of total liver complementary DNA (cDNA) using the following primers: (1) loop-out sense primer, 5'-ctgggtaccgggccctGGGACCTTTACTTTATGG//CCATATAACATTTACCCTCA-3', corresponding to murine factor VIII cDNA5 nucleotides 1402-1490 (in caps) with the deletion of nucleotides 1421-1469, where the underlined region designates the ApaI restriction site and the // designates the position of the deletion, and (2) antisense primer, 5'-CACCGCGGTGGCGGCCGCATAGACCATTTTGTGTTTGAA-3', corresponding to nucleotides 1884-1923, where the underlined region contains a NotI restriction site. The PCR product containing the loop-out region was cloned into the pBluescript II KS-phagemid (Stratagene, La Jolla, CA) using the vector ApaI/NotI restriction sites. The VWF competitor RNA was constructed by PCR amplification of total liver cDNA using the following primers based on the sequence of murine VWF exon 2823 using the human full-length pre-pro-VWF cDNA numbering system24: (1) loop-out sense primer, 5'-ccggaattccggCAGATCCGCCTCATCGAGAAGC AGG//AGCTACCTCTGTGACCTTGC-3', corresponding to nucleotides 4369-4481 (in caps), where the underlined region designates the EcoRI restriction site and the // designates the position of the deletion, and (2) antisense primer, 5'-CGCGGATCCGCGGCCGCCCTGGTAGCGGATCTC-3', corresponding to nucleotides 4798-4830, where the underlined region designates a BamHI restriction site. The VWF loop-out PCR product was cloned as described above using the EcoRI/BamHI restriction sites. cRNA molecules were generated by in vitro transcription using T3 RNA polymerase. Transcripts were purified using RNeasy spin columns (Qiagen, Valencia, CA) and quantitated spectrophotometrically.Competitive RT-PCR was performed using the One-Step RT-PCR Kit (Qiagen) following the manufacturer's protocol. Two hundred nanograms total RNA was used along with serial dilutions of competitor cRNA in a final reaction volume of 50 µL. The sequences of the sense and antisense factor VIII PCR primers used were 5'-TGGGACCTTTACTTTATGG-3' and 5'-AAAAACATAGCCATTGATGCTGTG-3', respectively. The sequences of the VWF PCR sense and antisense primers were 5'-GAGATCCGCTACCAGGGCGGC-3' and 5'-GCCGCCCTGGTAGCGGATCTC-3', respectively. PCR reactions were performed in a Hybaid OmniGene thermocycler. The conditions for factor VIII DNA amplification were 55°C, 35 minutes (1 cycle); 95°C, 5 minutes (1 cycle); 95°C, 1 minute, 58°C, 1 minute, 72°C, 1 minute (35 cycles); 72°C, 10 minutes (1 cycle); and 30°C, 30 seconds (1 cycle). The conditions for VWF amplification were 55°C, 35 minutes (1 cycle); 95°C, 15 minutes (1 cycle); 95°C, 1 minute, 68°C, 1 minute, 72°C, 1 minute (35 cycles); 72°C, 10 minutes and 30°C, 30 seconds (1 cycle). PCR products were visualized by agarose gel electrophoresis and quantitated densitometrically as described previously.11
Induction of FHF in mice Eight- to 12-week-old male C57BL/6 mice received intraperitoneal injections of 0, 15, 30, and 50 µg/g body weight AOM (saline control, AOM-15, AOM-30, and AOM-50, respectively). Mice in the AOM-30 and AOM-50 groups became lethargic within 8 hours, indicative of stage II hepatic encephalopathy. In contrast, AOM-15 mice maintained normal activity. All AOM-30 and AOM-50 mice developed coma (stage IV hepatic encephalopathy) and died, whereas AOM-15 mice remained asymptomatic until 72 hours after injection, at which time they were killed. The average postinjection survival times in the AOM-30 and AOM-50 groups were 45 and 33 hours, respectively. These results are consistent with those of the original report of AOM-induced murine FHF, in which 20 µg/g body weight of AOM was not toxic, but 50 µg/g body weight was uniformly fatal.22Liver, spleen, kidney, and lung tissues from the control and AOM groups
were evaluated histologically. Liver sections from the AOM-30 and
AOM-50 groups displayed moderate and severe multifocal necrosis,
respectively, with apparent sparing of liver sinusoidal endothelial
cells (Figure 1A). Hepatocellular
necrosis was not evident in the AOM-15 and saline control tissues.
Spleen, kidney, and lung tissues from mice in all groups appeared
normal (not shown). VWF protein was detected in control and AOM-50 mice
by immunofluorescence. AOM-50 mice displayed intense staining for VWF
antigen within the vascular and sinusoidal endothelium (Figure 1B).
This result also is consistent with the proposal that AOM is
specifically toxic to hepatocytes.22
Levels of plasma factors V, VII, and IX in AOM-treated mice The synthesis of the vitamin K-dependent coagulation proteins, which include prothrombin, factors VII, IX, and X, protein C, protein S, and protein Z, occurs in hepatocytes. Factor V is expressed in hepatocytes and also in megakaryocytes and possibly certain types of endothelial cells.25 Compared to control mice, plasma levels of factors V, VII, and IX were normal or slightly increased in the AOM-15 group, but were markedly decreased in the AOM-30 and AOM-50 groups (Table 1). Levels of factors V and VII were less than 2% of control, whereas the reduction in factor IX was not as severe. This may be due to a longer circulatory life of factor IX compared to other coagulation factors.26 The data correlate well with the hepatic necrosis observed in the treatment groups. The decrease in activity of these factors mimics the presentation of human FHF.
Plasma factor VIII levels in AOM-treated mice Activity of factor VIII decreased with time in a dose-dependent fashion (Figure 2). In the AOM-30 and AOM-50 groups, there was a progressive decline to less than 10% of initial levels until death. In the AOM-15 group, activity of factor VIII appeared to decrease during the first 30 hours, but returned to normal by the end of the experiment. An equal volume of normal mouse plasma completely corrected the clotting defect in plasma from AOM-treated mice, excluding the possibility that these results were due to a nonspecific inhibitor of the aPTT-based factor VIII assay or a specific inhibitor of factor VIII (data not shown).
Steady-state factor VIII hepatic mRNA levels in AOM-treated mice Competitive RT-PCR analysis for factor VIII mRNA was performed on total liver RNA from control and AOM-treated groups (Figure 3A). As a control, competitive RT-PCR of VWF mRNA, which is synthesized in liver sinusoidal endothelial cells but not hepatocytes, also was done (Figure 3B). In this method,11,27-29 known amounts of synthetic competitor cRNA, corresponding to the amplified region except for a small looped-out segment, is added to the total RNA sample. The cDNA produced from the cRNA is a competitive inhibitor in the PCR reaction and produces a band with slightly greater electrophoretic mobility. The point of equivalence, where the amount of each PCR product is equal, yields the desired number of copies of mRNA. The point of equivalence was determined by linear regression of the log ratio of cRNA/mRNA band intensity versus log cRNA concentration. The factor VIII mRNA levels were significantly decreased in the AOM-15, AOM-30, and AOM-50 groups (P = .034, .028, and .023, respectively, t test) to approximately 20% of control values (Figure 3C). In contrast, VWF mRNA levels were not changed at any dose of AOM, indicating that vascular and sinusoidal endothelial cells remain functionally intact in AOM-induced FHF. The factor VIII mRNA levels in spleen, kidney, or lung tissue were not changed in any of the AOM groups (data not shown).
Several interesting and apparently disparate observations have been made related to the biosynthesis of factor VIII. Liver transplantation in human and canine hemophilia A results in an increase in factor VIII levels to normal, and thus cures the bleeding diathesis.8-10 However, transplantation of liver from hemophilia A dogs to normal dogs does not produce hemophilia A.10 These findings indicate that the liver is sufficient but not necessary for factor VIII synthesis. However, extrahepatic sites of hemostatically significant factor VIII synthesis have not been identified conclusively. Human and canine hemophilia A are not cured by bone marrow or kidney transplantation.10,30-32 Spleen transplantation in hemophilia A dogs has yielded conflicting results, probably due to poor graft survival.33-35 Transplantation of normal spleen cells into patients with hemophilia A reportedly produced factor VIII levels over 30% of normal for up to 4 months,36,37 but these results have not been confirmed. Additionally, spleen transplantation in humans did not produce increased factor VIII levels in another study.31 The spleen is not necessary for production of normal factor VIII levels because splenectomy is not associated with a decrease in levels. FHF, defined as hepatic failure with stage III (deep somnolence) or IV
(coma) encephalopathy that develops in less than 8 weeks in the absence
of pre-existing liver disease, is associated with increased factor VIII
levels in humans.16-19,38 In contrast, all other hepatic
coagulation and fibrinolytic factors, including fibrinogen;
prothrombin; factors V, VII, IX, X, XI, XII, and XIII; prekallikrein;
high-molecular-weight kininogen; protein C; plasminogen; antithrombin
III; and Human FHF usually is due to acetaminophen (paracetamol) overdose or viral hepatitis. Viral hepatitis is associated with higher elevations of factor VIII than acetaminophen toxicity, possibly due to the longer disease course in viral hepatitis.17 However, in 8 cases of FHF due to Amanita phalloides mushroom poisoning, factor VIII levels were normal, whereas levels of prothrombin, factors V, VII, IX, and X, and plasminogen were severely reduced.43 Thus, within the clinical setting of FHF, different mechanisms of liver injury have differential effects on factor VIII expression. FHF is a setting that could provide valuable insights into the control of factor VIII expression. However, it has been difficult to develop animal models of FHF.44 Acetaminophen and carbon tetrachloride, which reliably produce FHF in humans, have inconsistent effects in mice and other animals. Additionally, there is no widely used model of FHF due to viral hepatitis. Galactosamine, which has been used as a hepatotoxin in rabbits, dogs, rats, and mice, produces variable results, is not a cause of FHF in humans, and produces a different histologic pattern of injury than other FHF syndromes.22,44,45 The recent report that AOM produces FHF in mice prompted us to investigate its effect on the synthesis of factor VIII and other coagulation factors. We found that AOM reproducibly produced hepatic necrosis, FHF, and death in C57BL/6 mice in a dose-dependent manner similar to the original report.22 At the highest doses of AOM used (30 and 50 µg/g body weight), there was a dramatic drop in factor VIII levels, as well as factors V, VII, and IX (Table 1). The decrease in factor VIII was associated with a decrease in factor VIII mRNA in liver (Figure 3A,C), but not kidney, lung, or spleen. In contrast, hepatic VWF mRNA and antigen levels did not decrease in AOM-mediated FHF (Figure 3B,C). Because VWF is synthesized by endothelial cells, including liver sinusoidal endothelium, but not hepatocytes,11,46 the results indicate that AOM produces selective necrosis of hepatocytes and spares liver sinusoidal endothelial cells and extrahepatic tissues. Although factor VIII levels in the AOM-15 group decreased only transiently, there was a decrease in hepatic factor VIII mRNA levels in this group similar to that observed in the AOM-30 and AOM-50 groups (Figure 3C). This indicates that defects in factor VIII synthesis at the translational or posttranslational level are a major cause of the decrease in factor VIII levels in the AOM-30 and AOM-50 groups. Alternatively, local extracellular degradation of newly synthesized factor VIII, perhaps by proteolysis associated with necrosis or apoptosis possibly is an important factor. The decrease in factor VIII levels in this model is in contrast to the elevated factor VIII levels that are induced by acetaminophen or viral hepatitis in humans. In these settings, extracellular signals could be generated in response to liver injury that promote extrahepatic or liver sinusoidal endothelial cell factor VIII synthesis. The mechanism of the injury produced by AOM in mice, which is unknown,22 may differ qualitatively or in degree of severity such that these signals are not produced, which may be species specific or a general property of AOM-induced liver injury. Further investigation into the pathophysiology of AOM-induced liver injury will be necessary to address this issue.
We wish to thank Dr Dirck Dillehay in the Division of Animal Resources at Emory University for his evaluation of the histologic specimens.
Submitted October 10, 2001; accepted February 25, 2002.
Supported by grant R01-HL40921 from the National Institutes of Health.
The publication costs of this article were defrayed in part by page charge payment. Therefore, and solely to indicate this fact, this article is hereby marked "advertisement" in accordance with 18 U.S.C. section 1734.
Reprints: Pete Lollar, Winship Cancer Institute, 1639 Pierce Dr, Rm 1003, Woodruff Memorial Bldg, Emory University, Atlanta, GA 30322; e-mail: jlollar{at}emory.edu.
1. Bloom AL. The biosynthesis of factor VIII. Clin Haematol. 1979;8:53-77[Medline] [Order article via Infotrieve]. 2. Graham JB, Collins DL, Brinkhous KM. Assay of plasma antihemophilic activity in normal, heterozygous (hemophilia) and prothrombinopenic dogs. Proc Soc Exp Biol Med. 1951;77:294-296[CrossRef][Medline] [Order article via Infotrieve]. 3. Norman JC, Lambilliotte JP, Kojima Y, Sise HS. Antihemophilic factor release by perfused liver and spleen: relationship to hemophilia. Science. 1967;58:1060-1061.
4.
Lenting PJ, van Mourik JA, Mertens K.
The life cycle of coagulation factor VIII in view of its structure and function.
Blood.
1998;92:3983-3996 5. Elder B, Lakich D, Gitschier J. Sequence of the murine factor VIII cDNA. Genomics. 1993;16:374-379[CrossRef][Medline] [Order article via Infotrieve].
6.
Ringwald M, Eppig JT, Begley DA, et al.
The mouse gene expression database.
Nucleic Acids Res.
2001;29:98-101 7. Wion KL, Kelly D, Summerfield JA, Tuddenham EG, Lawn RM. Distribution of factor VIII mRNA and antigen in human liver and other tissues. Nature. 1985;317:726-729[CrossRef][Medline] [Order article via Infotrieve].
8.
Bontempo FA, Lewis JH, Gorenc TJ, et al.
Liver transplantation in hemophilia A.
Blood.
1987;69:1721-1724 9. Scharrer I, Encke A, Hottenrott C. Clinical cure of haemophilia A by liver transplantation. Lancet. 1988;2:800-801[Medline] [Order article via Infotrieve].
10.
Webster WP, Zukoski CF, Hutchin P, et al.
Plasma factor VIII synthesis and control as revealed by canine organ transplantation.
Am J Physiol.
1971;220:1147-1154
11.
Do H, Healey JF, Waller EK, Lollar P.
Expression of factor VIII by murine liver sinusoidal endothelial cells.
J Biol Chem.
1999;274:19587-19592 12. Hellman L, Smedsrod B, Sandberg H, Pettersson U. Secretion of coagulant factor VIII activity and antigen by in vitro cultivated rat liver sinusoidal endothelial cells. Br J Haematol. 1989;73:348-355[Medline] [Order article via Infotrieve]. 13. Stel HV, van der Kwast TH, Veerman EC. Detection of factor VIII/coagulant antigen in human liver tissue. Nature. 1983;303:530-532[CrossRef][Medline] [Order article via Infotrieve].
14.
van der Kwast TH, Stel HV, Cristen E, Bertina RM, Veerman EC.
Localization of factor VIII-procoagulant antigen: an immunohistological survey of the human body using monoclonal antibodies.
Blood.
1986;67:222-227 15. Zelechowska MG, van Mourik JA, Brodniewicz-Proba T. Ultrastructural localization of factor VIII procoagulant antigen in human liver hepatocytes. Nature. 1985;317:729-730[CrossRef][Medline] [Order article via Infotrieve]. 16. Baele G, Vermeire P, Demeulenaere L, Barbier F. Elevation of factor VIII in acute liver necrosis. Influence of plasmapheresis. Digestion. 1973;8:360-367[CrossRef][Medline] [Order article via Infotrieve]. 17. Langley PG, Hughes RD, Williams R. Increased factor VIII complex in fulminant hepatic failure. Thromb Haemost. 1985;54:693-696[Medline] [Order article via Infotrieve]. 18. Meili EO, Straub PW. Elevation of factor VIII in acute fatal liver necrosis. Thromb Diath Haemorrh. 1970;24:161-174[Medline] [Order article via Infotrieve].
19.
Pereira LM, Langley PG, Hayllar KM, Tredger JM, Williams R.
Coagulation factor V and VIII/V ratio as predictors of outcome in paracetamol induced fulminant hepatic failure: relation to other prognostic indicators.
Gut.
1992;33:98-102 20. Castelino DJ, Salem HH. Natural anticoagulants and the liver. J Gastroenterol Hepatol. 1997;12:77-83[Medline] [Order article via Infotrieve]. 21. Langley PG, Williams R. The effect of fulminant hepatic failure on protein C antigen and activity. Thromb Haemost. 1988;59:316-318[Medline] [Order article via Infotrieve]. 22. Matkowskyj KA, Marrero JA, Carroll RE, et al. Azoxymethane-induced fulminant hepatic failure in C57BL/6J mice: characterization of a new animal model. Am J Physiol. 1999;277:G455-G462[Medline] [Order article via Infotrieve].
23.
Nichols WC, Cooney KA, Mohlke KL, et al.
von Willebrand disease in the RIIIS/J mouse is caused by a defect outside of the von Willebrand factor gene.
Blood.
1994;83:3225-3231
24.
Bonthron D, Orr EC, Mitsock LM, et al.
Nucleotide sequence of pre-pro-von Willebrand factor cDNA.
Nucleic Acids Res.
1986;14:7125-7127 25. Hoyer LW, Wyshock EG, Salzman EW. Coagulation cofactors: factors V and VIII. In: Coleman RW,Hirsch J,Marder VJ,Salzman EW, eds. Hemostasis and Thrombosis. Basic Principles and Clinical Practice. Philadelphia, PA: Lippincott; 1994:109-133. 26. Edmunds LH, Salzman EW. Hemostatic problems, transfusion therapy, and cardiopulmonary bypass in surgical patients. In: Coleman RW,Hirsch J,Marder VJ,Salzman EW, eds. Hemostasis and Thrombosis: Basic Principles and Clinical Practice. Philadelphia, PA: Lippincott; 2001:956-968. 27. Powell EE, Kroon PA. Measurement of mRNA by quantitative PCR with a nonradioactive label. J Lipid Res. 1992;33:609-614[Abstract]. 28. Saghizadeh M, Ong JM, Garvey WT, Henry RR, Kern PA. The expression of TNF alpha by human muscle. Relationship to insulin resistance. J Clin Invest. 1996;97:1111-1116[Medline] [Order article via Infotrieve].
29.
Wang AM, Doyle MV, Mark DF.
Quantitation of mRNA by the polymerase chain reaction.
Proc Natl Acad Sci U S A.
1989;86:9717-9721 30. Koene RA, Gerlag PG, Jansen JL, et al. Successful haemodialysis and renal transplantation in a patient with haemophilia A . Proc Eur Dial Transplant Assoc. 1977;14:401-406[Medline] [Order article via Infotrieve].
31.
Marchioro TL, Hougie C, Ragde H, Epstein RB, Thomas ED.
Hemophilia: role of organ homografts.
Science.
1969;163:188-190
32.
Storb R, Marchioro TL, Graham TC, et al.
Canine hemophilia and hemopoietic grafting.
Blood.
1972;40:234-238 33. Hathaway WE, Mull MM, Githens JH, et al. Attempted spleen transplant in classical hemophilia. Transplantation. 1969;7:73-75[Medline] [Order article via Infotrieve]. 34. Norman JC, Covelli VH, Sise HS. Transplantation of the spleen: experimental cure of hemophilia. Surgery. 1968;64:1-14[Medline] [Order article via Infotrieve]. 35. Norman JC, Covelli VH, Sise HS. Experimental transplantation of the spleen for classical hemophilia A. Rationales and long-term results. Bibl Haematol. 1970;34:187-199[Medline] [Order article via Infotrieve].
36.
Liu DL, Xia S, Tang J, Qin X, Liu H.
Allotransplantation of whole spleen in patients with hepatic malignant tumors or hemophilia A. Operative technique and preliminary results.
Arch Surg.
1995;130:33-39 37. Liu L, Xia S, Seifert J. Transplantation of spleen cells in patients with hemophilia A. A report of 20 cases. Transpl Int. 1994;7:201-206[CrossRef][Medline] [Order article via Infotrieve].
38.
Maisonneuve P, Sultan Y.
Modification of factor VIII complex properties in patients with liver disease.
J Clin Pathol.
1977;30:221-227 39. Fiore L, Levine J, Deykin D. Alterations in hemostasis in patients with liver disease. In: Zakim D,Boyer TD, eds. Hepatology. A Textbook of Liver Disease. Philadelphia, PA: Saunders; 1990:546-566. 40. Baele G, Matthijs E, Barbier F. Antihaemophilic factor A activity, F VIII-related antigen and von Willebrand factor in hepatic cirrhosis. Acta Haematol. 1977;57:290-297[Medline] [Order article via Infotrieve]. 41. Green AJ, Ratnoff OD. Elevated antihemophilic factor (AHF, factor VIII) procoagulant activity and AHF-like antigen in alcoholic cirrhosis of the liver. J Lab Clin Med. 1974;83:189-197[Medline] [Order article via Infotrieve]. 42. Kelly DA, O'Brien FJ, Hutton RA, et al. The effect of liver disease on factors V, VIII and protein C. Br J Haematol. 1985;61:541-548[Medline] [Order article via Infotrieve]. 43. Meili EO, Frick PG, Straub PW. Coagulation changes during massive hepatic necrosis due to Amanita phalloides poisoning with special reference to antihemophilic globulin. Helv Med Acta. 1970;35:304-313[Medline] [Order article via Infotrieve]. 44. Terblanche J, Hickman R. Animal models of fulminant hepatic failure. Dig Dis Sci. 1991;36:770-774[CrossRef][Medline] [Order article via Infotrieve]. 45. Blitzer BL, Waggoner JG, Jones EA, et al. A model of fulminant hepatic failure in the rabbit. Gastroenterology. 1978;74:664-671[Medline] [Order article via Infotrieve].
46.
Yamamoto K, de W V, Fearns C, Loskutoff DJ.
Tissue distribution and regulation of murine von Willebrand factor gene expression in vivo.
Blood.
1998;92:2791-2801
© 2002 by The American Society of Hematology.
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 |
|
 |
|
  N. Yadav, S. Kanjirakkuzhiyil, S. Kumar, M. Jain, A. Halder, R. Saxena, and A. Mukhopadhyay The therapeutic effect of bone marrow-derived liver cells in the phenotypic correction of murine hemophilia A Blood, November 12, 2009; 114(20): 4552 - 4561. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Lozier Factor VIII biosynthesis: new inspirations? Blood, July 15, 2006; 108(2): 414 - 415. [Full Text] [PDF]
|
|
|
|
|
|
C. B. Doering, E. T. Parker, C. E. Nichols, and P. Lollar Decreased factor VIII levels during acetaminophen-induced murine fulminant hepatic failure Blood, September 1, 2003; 102(5): 1743 - 1744. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 |
 |
 |
|||||||
 |
 |
 |
 |
 |
 |
 |
 |
||
| Copyright © 2002 by American Society of Hematology Online ISSN: 1528-0020 | |||||||||
Top
Abstract
Introduction
70°C. Citrated human factor V-, VII-, VIII-, and IX-deficient plasmas and normal pooled human plasma (FACT) were purchased from George King Biomedical (Overland Park, KA). Neoplastine was purchased from Diagnostica Stago (Asnieres, France). Automated activated partial
thromboplastin time (aPTT) reagent was purchased from Organon Teknika
(Durham, NC). Oligonucleotides were synthesized by Gibco BRL
(Gaithersburg, MD).
2-antiplasmin are decreased in
FHF.