The Development and Characterisation of Antibodies to Human Factor VIII in Haemophilic Dogs

1987 ◽  
Vol 57 (03) ◽  
pp. 314-321 ◽  
Author(s):  
Janet D Littlewood ◽  
T W Barrowcliffe
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Kinetic Studies ◽  
Cross Reaction ◽  
High Responder ◽  
Type Ii ◽  
Human Factor Viii ◽  
Factor Viii Concentrates ◽  
Low Responder

SummaryFour haemophilic dogs received infusions of human factor VIII concentrates, and developed inhibitors to human F VIII. These inhibitors cross-reacted with canine F VIII with parallel increases and decreases in titre. Cross-reaction was also found to porcine F VIII but changes in titre did not correlate with anti-human and anti-canine titres. These inhibitors were found to be immunoglobulins, and antibodies were detected against other proteins found in concentrates. Kinetic studies showed that in all four dogs the F VIII inhibitors were Type II antibodies. One of the dogs behaved as a “high-responder”, whilst another was more analogous to a “low-responder” patient. Phospholipid protection experiments in vitro demonstrated that some antibodies could be prevented from inhibiting F VIII, and porcine F VIII was particularly well protected against inhibition.

scholarly journals Human Factor VIII Concentrates in Hemophiliac Dogs

1977 ◽  
Author(s):  
Jessica H. Lewis ◽  
Ute Hasiba ◽  
Joel A. Spero
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Rapid Development ◽  
The Third ◽  
Human Factor Viii ◽  
Post Infusion ◽  
Factor Viii Concentrates ◽  
In Vitro Effects

Human factor VIII corrects the clotting defect in dog hemophilic plasma in vitro. The present studies were undertaken to see if this happened in vivo and to look for and document the development of an inhibitor. Four hemophiliac dogs were infused with factor VIII concentrates, the first two on five occasions, the others three times. Factor VIII:C, VIIIR:Ag (defined with antibody to human VIII) and VIIIR:vW were followed at pre, 10 minutes, 2 and 24 hours post infusion. The pre-infusion VIII:C (assayed with human substrate) averaged 0.23 U/ml compared to 6.93 U/ml for normal dogs; VIIIR:Ag was absent in both. VIIIR:vW was low but variable. Following the first injection, all four dogs responded in VIII:C about as calculated. The amounts of VIIIR:Ag and vW were much greater than VIII:C in the concentrates and in the post-first infusion samples from the dogs. On subsequent infusions rises in VIIIR:Ag were not detected and increases in VIII:C and VIIIR:vW were minimal. Precipitating anti-human VIII was found on the third infusion and thereafter. After the first infusion reactions were marked. Vomiting and diarrhea occurred in all, and one dog died in anaphylactic shock about one hour after the third infusion. Lack of response in VIIIR:Ag occurred before anti-VIII could be demonstrated in vitro. This rapid development of an inhibitor suggests that prolonged cross-species VIII therapy will not be successful. The ability of the precipitating anti-VIII elicited in the dogs to destroy VIII:C, VIIIR:Ag and VIIIR:vW is analagous to the in vitro effects of heterologous anti-VIIIs (rabbit and goat).

Impaired Prothrombin Consumption in Bernard-Soulier Syndrome Is Corrected In Vitro by Human Factor VIII

1997 ◽  
Vol 77 (02) ◽  
pp. 383-386 ◽  
Author(s):  
S Bellucci ◽  
J P Girma ◽  
M Lozano ◽  
D Meyer ◽  
J P Caen
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Platelet Membrane ◽  
Giant Platelets ◽  
Prolonged Bleeding Time ◽  
Human Factor Viii ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Bernard Soulier Syndrome

SummaryThe Bernard-Soulier syndrome (BSS) is characterized by thrombocytopenia with giant platelets, a prolonged bleeding time with defective platelet adhesion to the subendothelium related to a defect in platelet membrane glycoprotein lb (GPIb) and a decreased prothrombin consumption. The mechanism of the latter abnormality remains unknown. In this study, we showed that this defect was corrected by the addition of purified human factor VIII (FVIII) to blood from four patients with BSS. The correction of prothrombin consumption was almost complete at concentrations between 1.5 and 3 IU/ml of FVIII procoagulant activity (VIII.'C) and partially abolished by a monoclonal antibody which neutralizes VIII:C. This correction was specific for FVIII and was not observed after addition of purified human FIX. It was obtained, in the same magnitude range, with FVIII complexed to von Willebrand factor (vWF) but not with free vWF. These data provide a new insight into the knowledge of the physiological interaction between the platelet membrane and the vWF-FVIII complex facilitating plasma coagulation activation and may lead to helpful therapeutic advances.

Localization of epitopes for human factor VIII inhibitor antibodies by immunoblotting and antibody neutralization

Blood ◽  
1989 ◽  
Vol 74 (5) ◽  
pp. 1618-1626 ◽  
Author(s):  
D Scandella ◽  
M Mattingly ◽  
S de Graaf ◽  
CA Fulcher
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Factor Viii Inhibitor ◽  
Type I ◽  
Protein Fragments ◽  
Human Factor Viii ◽  
Circulating Antibodies ◽  
A1 Domain ◽  
A2 Domain

Human factor VIII(FVIII) inhibitors are pathologic, circulating antibodies that inactivate FVIII. We have examined the location of epitopes on the FVIII protein for inhibitors from hemophilia A and nonhemophilic individuals. The inhibitors were of type I or type II in the kinetics of their inactivation of FVIII. A cDNA clone of human FVIII was used to express defined FVIII protein fragments in Escherichia coli for immunoblotting with inhibitor plasma. An epitope for 18 heavy-chain inhibitors was localized to the aminoterminal 18.3 Kd of the A2 domain. Two of these inhibitors also recognized an epitope located between A1 and A2 domains. Similarly, an epitope for 23 light- chain inhibitors was localized to the C2 domain. Weaker epitopes for 13 of the same inhibitors within the C1 and C2 domains were also observed. Four of the 23 inhibitors in addition bound strongly to the A3 domain. Most inhibitors (22 of 23) were neutralized in vitro only by the FVIII fragments to which they bound on immunoblots; however, one inhibitor that was neutralized by a fragment containing the A1 domain did not bind to it on immunoblots. Conversely, 3 of 3 inhibitors that bound to the A3 domain and 5 of 15 that bound to the A2 domain were not neutralized by the corresponding fragments. The epitope specificity of an inhibitor did not depend on its source or type. Our results show that FVIII inhibitors bind to limited areas within the heavy and light chains of FVIII. Some inhibitor plasmas contain additional antibodies that may not be inhibitory.

scholarly journals A large region (approximately equal to 95 kDa) of human factor VIII is dispensable for in vitro procoagulant activity.

1986 ◽  
Vol 83 (16) ◽  
pp. 5939-5942 ◽  
Author(s):  
J. J. Toole ◽  
D. D. Pittman ◽  
E. C. Orr ◽  
P. Murtha ◽  
L. C. Wasley ◽  
...  
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Procoagulant Activity ◽  
Large Region ◽  
Human Factor Viii

scholarly journals Clinical experience with polyelectrolyte-fractionated porcine factor VIII concentrate in the treatment of hemophiliacs with antibodies to factor VIII

Blood ◽  
1984 ◽  
Vol 63 (1) ◽  
pp. 31-41 ◽  
Author(s):  
PB Kernoff ◽  
ND Thomas ◽  
PA Lilley ◽  
KB Matthews ◽  
E Goldman ◽  
...  
Keyword(s):  
Factor Viii ◽  
Clinical Experience ◽  
Human Factor ◽  
Intermediate Level ◽  
Human Factor Viii ◽  
Plasma Factor ◽  
Post Infusion ◽  
Clinical Responses ◽  
Circulating Antibodies

Circulating antibodies to factor VIII (anti-VIII, “inhibitors”) occurring in patients with hemophilia neutralize porcine factor VIII less readily than human factor VIII in vitro. Over an 18-mo period, 8 patients with anti-VIII were treated with 45 courses (297 infusions) of polyelectrolyte-fractionated porcine factor VIII concentrate (PE porcine VIII). Where no anti-PE porcine VIII was detectable, mean post- infusion rise in plasma factor VIII was 1.29 U/dl/units infused/kg. Above 13 Old Oxford units of anti-PE porcine VIII and 48 Bethesda units of anti-human VIII, there were no postinfusion rises in plasma factor VIII. Where postinfusion rises were detected, clinical responses were good and conventional methods could be used to guide dosage. Ten percent of infusions were followed by febrile reactions, but these were usually mild and decreased in frequency and severity with increasing exposure. Multiple and prolonged courses of therapy were given to some patients without evidence of loss of clinical or laboratory efficacy. PE porcine VIII could provoke anamnestic rises of anti-VIII in susceptible patients, but appeared to have a lower immunogenic potential than human VIII. PE porcine VIII is a rational and effective therapeutic alternative for patients with anti-VIII, particularly those with intermediate level inhibitors who cannot be managed effectively using human factor VIII.

Polyelectrolyte Fractionated Porcine Factor VIII Concentrate In The Treatment Of Haemophiliacs With Antibodies To Factor VIII: C

1981 ◽  
Author(s):  
P B A Kernoff ◽  
N D Thomas ◽  
P A Lilley ◽  
E G D Tuddenham
Keyword(s):  
Factor Viii ◽  
Adverse Reactions ◽  
Human Factor ◽  
High Plasma ◽  
Major Drawback ◽  
Therapeutic Value ◽  
Human Factor Viii ◽  
Clinical Responses ◽  
Bleeding Episodes

Antibodies to procoagulant factor VIII (anti-VIII:C) occurring in patients with haemophilia neutralise porcine factor VIII:C less readily than human factor VIII: C in vitro. Porcine factor VIII concentrate (porcine VIII) therefore has potential advantages in the treatment of such patients. Polyelectrolyte-fractionated porcine VIII (PE porcine VIII) lacks a major drawback of earlier preparations of porcine VIII in that it contains negligible quantities of platelet aggregating factor (PAF). The purpose of this study was to make a preliminary clinical assessment of the therapeutic value of PE porcine VIII. Over 6 months, 12 courses of treatment were given to four patients with circulating anti-VIII: C. Bleeding episodes treated ranged from the potentially lethal to moderately severe joint and muscle haemorrhages. Duration of courses was from 24 hrs. to more than 3 weeks. Clinical responses were strikingly good and no patient developed thrombocytopenia. Occasional mild pyrogenic-type transfusion reactions were encountered, but these were easily controlled. Dose- response relationships were most favourable in patients with low pre-infusion levels of anti-VIII: C activity against PE porcine VIII but excellent clinical responses could be obtained without achieving high plasma VIII: C levels. Multiple courses of therapy (up to 6) were given to individual patients without evidence of loss of clinical or laboratory efficacy, or an increased tendency to adverse reactions. There was no evidence of resistance in the patient who was treated daily for more than 3 weeks. Only 1 course of therapy was followed by a classical anamnestic rise in anti-VIII: C, and this course had included human factor VIII. PE porcine VIII appears to have a low immunogenic potential, and is a rational and effective therapeutic alternative for patients with anti-VIII: C.

scholarly journals The Effects of Injection of Human Factor VIII Antibody Into Rabbits

Blood ◽  
1973 ◽  
Vol 42 (4) ◽  
pp. 509-521 ◽  
Author(s):  
S. M-C. Shen ◽  
D. I. Feinstein ◽  
S. I. Rapaport
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Rabbit Model ◽  
Kinetic Studies ◽  
Factor Vii ◽  
Factor V ◽  
Initial Values ◽  
Human Factor Viii ◽  
Hemolytic Complement Activity ◽  
Antigen Antibody

Abstract Rabbits were injected with an immunoglobulin fraction of human serum containing a factor VIII antibody. Factor VIII levels fell abruptly, persisted below 10% of a rabbit plasma standard for 12 hr, and returned to normal by 120-168 hr. The factor VIII antigen-antibody reaction did not result in Intravascular clotting as evaluated by kinetic studies with 125I-fibrinogen. However, small falls in factor V and factor VII levels were observed over a 6-hr period after the injection. Platelets fell to about one-half of initial values within 15 min, rose to 80% of initial levels over 2 hr, and subsequently declined to 65%-70% of initial levels. WBC levels fell to below 20% of initial values 2 hr after the injection but returned to about 75% of initial values by 6 hr. Total hemolytic complement activity was unaffected. Animals made granulocytopenic with nitrogen mustard and animals with hereditary C'6 deficiency behaved similarly to normal animals. One may conclude that the injection of human factor VIII antibody into rabbits produces a rabbit model with impaired intrinsic coagulation suitable for studies of the mechanism of endotoxin-induced intravascular clotting.

Evaluation of an Adenoviral Vector Encoding Full-Length Human Factor VIII in Hemophiliac Mice

1999 ◽  
Vol 81 (02) ◽  
pp. 234-239 ◽  
Author(s):  
Sheila Connelly ◽  
Julie Andrews ◽  
Angela Gallo-Penn ◽  
Luigina Tagliavacca ◽  
Randal Kaufman ◽  
...  
Keyword(s):  
Factor Viii ◽  
Adenoviral Vector ◽  
Human Factor ◽  
Hemophilia A ◽  
Adenoviral Vectors ◽  
Full Length ◽  
Human Factor Viii ◽  
Immunohistochemical Analyses

SummaryAdenoviral vectors provide a promising gene therapy system for the treatment of hemophilia A. Potent vectors encoding a human factor VIII (FVIII) cDNA were developed that mediated sustained FVIII expression in normal and hemophiliac mice and complete phenotypic correction of the bleeding disorder in hemophiliac mice and dogs (Connelly and Kaleko, Haemophilia 1998; 4: 380-8). However, these studies utilized vectors encoding a truncated version of the human FVIII cDNA lacking the B-domain (BDD FVIII). In this work, an adenoviral vector encoding the human full-length (FL) FVIII cDNA was generated and characterized. While functional FL FVIII was secreted in vitro, expression of the FL protein was not detected in the plasma of vector-treated hemophiliac mice. Unexpectedly, the FL FVIII vector-treated animals demonstrated phenotypic correction of the bleeding defect as measured by a tail-clip survival study. FL FVIII protein was visualized in the mouse livers using human FVIII-specific immunohistochemical analyses. These data demonstrate that adenoviral vector-mediated in vivo expression of BDD FVIII is more efficient than that of the FL protein and that phenotypic correction can occur in the absence of detectable levels of FVIII.

Concentration-dependent dissociation of factor VIII in 1 M NaCl

1976 ◽  
Vol 230 (2) ◽  
pp. 434-440 ◽  
Author(s):  
Sussman ◽  
W Rosner ◽  
HJ Weiss
Keyword(s):  
Factor Viii ◽  
Human Factor ◽  
Gel Filtration ◽  
Procoagulant Activity ◽  
Void Volume ◽  
Gradual Transition ◽  
Human Factor Viii ◽  
Factor Viii Concentrates ◽  
High Concentrations ◽  
Dilution Curves

Plasma, cryoprecipitate, Hemofil, and human factor VIII concentrate were dissolved in 1.0 M NaCl and chromatographed on Bio-Gel A-5m. With high concentrations of factor VIII the activity eluted as a symmetrical peak in the void volume; with a low factor VIII concentration the procoagulant activity was retarded. Dilution curves were performed for several human factor VIII concentrates. When the concentration of factor VIII was decreased, elution patterns showed a gradual transition from a peak in the void volume to a peak with a Ve/Vo of 1.7. Cryoprecipitate exhibited a similar behavior in 1.0 M NaCl, but the percent dissociation was greater than expected at high concentrations of factor VIII. When gel filtration was performed with 0.25 M CaCl2, significant dissociation occurred at all concentrations of factor VIII tested. The behavior of factor VIII in 1.0 M NaCl closely fit a theoretically derived curve for the dissociation of a protein from its binder. We conclude that the dissociation of factor VIII in 1 M NaCl is dependent on the concentration and purification of the procoagulant protein.

scholarly journals Clinical experience with polyelectrolyte-fractionated porcine factor VIII concentrate in the treatment of hemophiliacs with antibodies to factor VIII

Blood ◽  
1984 ◽  
Vol 63 (1) ◽  
pp. 31-41 ◽  
Author(s):  
PB Kernoff ◽  
ND Thomas ◽  
PA Lilley ◽  
KB Matthews ◽  
E Goldman ◽  
...  
Keyword(s):  
Factor Viii ◽  
Clinical Experience ◽  
Human Factor ◽  
Intermediate Level ◽  
Human Factor Viii ◽  
Plasma Factor ◽  
Post Infusion ◽  
Clinical Responses ◽  
Circulating Antibodies

Abstract Circulating antibodies to factor VIII (anti-VIII, “inhibitors”) occurring in patients with hemophilia neutralize porcine factor VIII less readily than human factor VIII in vitro. Over an 18-mo period, 8 patients with anti-VIII were treated with 45 courses (297 infusions) of polyelectrolyte-fractionated porcine factor VIII concentrate (PE porcine VIII). Where no anti-PE porcine VIII was detectable, mean post- infusion rise in plasma factor VIII was 1.29 U/dl/units infused/kg. Above 13 Old Oxford units of anti-PE porcine VIII and 48 Bethesda units of anti-human VIII, there were no postinfusion rises in plasma factor VIII. Where postinfusion rises were detected, clinical responses were good and conventional methods could be used to guide dosage. Ten percent of infusions were followed by febrile reactions, but these were usually mild and decreased in frequency and severity with increasing exposure. Multiple and prolonged courses of therapy were given to some patients without evidence of loss of clinical or laboratory efficacy. PE porcine VIII could provoke anamnestic rises of anti-VIII in susceptible patients, but appeared to have a lower immunogenic potential than human VIII. PE porcine VIII is a rational and effective therapeutic alternative for patients with anti-VIII, particularly those with intermediate level inhibitors who cannot be managed effectively using human factor VIII.

Sign in / Sign up

Export Citation Format

Share Document