Blood Coagulation Factor X Deficiency Causes Partial Embryonic Lethality and Fatal Neonatal Bleeding in Mice

2000 ◽  
Vol 83 (02) ◽  
pp. 185-190 ◽  
Author(s):  
Mieke Dewerchin ◽  
Zhong Liang ◽  
Lieve Moons ◽  
Peter Carmeliet ◽  
Francis Castellino ◽  
...  

SummaryMice with a total deficiency in blood coagulation Factor X (FX) were generated by targeted replacement of an 18-kb fragment of the FX gene, comprising all exons encoding the mature FX protein, with a neor cassette. The genotype distribution among the offspring from heterozygous breeding pairs suggested that FX deficiency resulted in partial embryonic lethality, with approximately one-third of the FX −/− embryos dying around embryonic day (E) 11.5-12.5. Two of 44 non-resorbed FX −/− embryos analyzed at these stages showed signs of massive bleeding, one of which into the brain ventricles, but no histological defects in the vasculature of these embryos or their yolk sac were observed. The remainder of the FX −/− embryos appeared normal and survived to term, but the majority of neonates (90%) died within 5 days, most frequently from intraabdominal bleeding. The remaining FX −/− animals succumbed between postnatal day (P)5 and P20 with intraabdominal, subcutaneous, or intracranial bleeding or a combination thereof. The lethal phenotype of the FX −/− mice illustrates the importance of FX function in embryonic and postnatal survival and demonstrates that these mice serve as effective models of the bleeding disorders observed in severe FX deficiency in humans.

1974 ◽  
Vol 31 (01) ◽  
pp. 040-051 ◽  
Author(s):  
Gustav Gaudernack ◽  
Åse Gladhaug Berre ◽  
Bjarne Østerud ◽  
Hans Prydz

SummaryMonospecific antisera against the human coagulation factor X have been raised in rabbits by injections of purified antigen. Such antiserum was used to study the cross-reacting material without factor X activity which is present in the blood of warfarin-treated patients and animals as well as to study the changes in factor X during coagulation. One patient with congenital factor X deficiency was also studied.A complete identity was found between factor X in Macaca mulatta and human blood. During warfarin treatment antigenically cross-reacting material appeared in plasma. This was not adsorbed on BaSO4, and inhibited the coagulation activity of normal factor X.Both this material, normal factor X and the cross-reacting material in plasma from a patient congenitally deficient in factor X gave rise to split products during coagulation by the intrinsic pathway, i. e. all of them served as substrates for the intrinsic activator of factor X.


Author(s):  
Antonio Girolami ◽  
Diana Noemi Garcia de Paoletti ◽  
Marcelo Leonardo Nenkies ◽  
Silvia Ferrari ◽  
Hugo Guglielmone

Background: Investigation of rare bleeding disorders in Latin-America. Objective: The report of a new case of FX deficiency due to a compound heterozygosis. Methods: Accepted clotting procedures were used. Sequencing of DNA was carried out by means of Applied Biosystems Instruments. Results: A compound heterozygote due to the association of a new mutation (Gla72Asp) with an already known mutation (Gly154Arg) of the FX gene is reported. The proposita is a 38 year old female who had a moderate bleeding tendency (menorrhagia, epistaxis, easy bruising). The proposita has never received substitution therapy but in the occasion of a uterine biopsy. The mother was asymptomatic but was a heterozygote for the new mutation. The father was asymptomatic but had deserted the family and could not be investigated. After this abandonment the mother of the proposita re-married with an asymptomatic man and she gave birth to a son who was asymptomatic but was also heterozygous for the new mutation (Gla72Asp). As a consequence it has to be assumed that the first husband of the mother of the proposita was heterozygous for the known mutation (Gly154Arg). Conclusion: This is the third case of a new mutation in the FX gene reported, during the past few years, in Argentina.


1988 ◽  
Vol 7 (5) ◽  
pp. 613-632
Author(s):  
John M. Beals ◽  
Joseph Weber ◽  
Paul Derwent ◽  
Kenneth L. Grant ◽  
Francis J. Castellino

2005 ◽  
Vol 93 (01) ◽  
pp. 40-47 ◽  
Author(s):  
Md. Abu Reza ◽  
Sanjay Swarup ◽  
Manjunatha Kini

SummaryIt is uncommon for similar pathways/systems to be involved in highly divergent functions within single organisms. Earlier, we have shown that trocarin D, a venom prothrombin activator, from the Australian rough-scaled snake Tropidechis carinatus, is structurally and functionally similar to the blood coagulation factor Xa (FXa). The presence of a haemostatic system in these snakes implies that they have two parallel prothrombin activating systems: one in the plasma, that participates in the life saving process of blood clotting and the other in their venom, where it acts as a toxin. Here, we report the complete cDNA sequence encoding the blood coagulation factor X (FX) from the liver of T. carinatus. Deduced T. carinatus FX sequence shows ~80% identity with trocarin D but ~50% identity with the mammalian FX. Our present study confirms the presence of two separate genes – one each for FX and trocarin D, that code for similar proteins in T. carinatus snake. These two genes have different expression sites and divergent uses suggesting that snake venom prothrombin activators have probably evolved by the duplication of the liver FX gene and subsequently marked for tissue-specific expression in the venom gland.


1990 ◽  
Vol 265 (2) ◽  
pp. 327-336 ◽  
Author(s):  
V J J Bom ◽  
R M Bertina

In the extrinsic pathway of blood coagulation, Factor X is activated by a complex of tissue factor, factor VII(a) and Ca2+ ions. Using purified human coagulation factors and a sensitive spectrophotometric assay for Factor Xa, we could demonstrate activation of Factor X by Factor VIIa in the absence of tissue-factor apoprotein, phospholipids and Ca2+. This finding allowed a kinetic analysis of the contribution of each of the cofactors. Ca2+ stimulated the reaction rate 10-fold at an optimum of 6 mM (Vmax. of 1.1 x 10(-3) min-1) mainly by decreasing the Km of Factor X (to 11.4 microM). In the presence of Ca2+, 25 microM-phospholipid caused a 150-fold decrease of the apparent Km and a 2-fold increase of the apparent Vmax. of the reaction; however, both kinetic parameters increased with increasing phospholipid concentration. Tissue-factor apoprotein contributed to the reaction rate mainly by an increase of the Vmax., in both the presence (40,500-fold) and absence (4900-fold) of phospholipid. The formation of a ternary complex of Factor VIIa with tissue-factor apoprotein and phospholipid was responsible for a 15 million-fold increase in the catalytic efficiency of Factor X activation. The presence of Ca2+ was absolutely required for the stimulatory effects of phospholipid and apoprotein. The data fit a general model in which the Ca2(+)-dependent conformation allows Factor VIIa to bind tissue-factor apoprotein and/or a negatively charged phospholipid surface resulting into a decreased intrinsic Km and an increased Vmax. for the activation of fluid-phase Factor X.


Viruses ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1399
Author(s):  
Brianna L. Bullard ◽  
Brigette N. Corder ◽  
Eric A. Weaver

Oncolytic adenoviruses (Ad) have shown promising results in the therapeutic treatment of cancer. Ad type 5 (Ad5) is the most extensively utilized Ad type. However, several limitations exist to using Ad5 as an oncolytic virus, including high levels of anti-Ad5 neutralizing antibodies in the population, binding of the Ad5 hexon to blood coagulation factor X leading to liver sequestration and toxicity, and reduced expression of the primary receptor CAR on many tumors. Here, we use in vitro methods to explore the oncolytic potential of four alternative Ad types (Ad26, 28, 45, and 48) belonging to the species D Ad subgroup and developed replication-competent species D Ads expressing the human sodium iodide symporter protein (hNIS) for combination radiovirotherapy. We evaluated the species D Ad vectors transduction, replication, cytotoxicity, and gene expression in six different cancer cell lines. Species D Ads showed the greatest transduction and cytotoxic killing in the SKBR3 breast cancer cells, followed by 293, A549, and HepG2 cells, however the cytotoxicity was less than the wild type Ad5 virus. In contrast, species D Ads showed limited transduction and cytotoxicity in the Hela and SKOV3 cancer cell lines. These species D Ad vectors also successfully expressed the hNIS gene during infection leading to increased iodide uptake in multiple cancer cell lines. These results, the low seroprevalence of anti-species D antibodies, and the lack of binding to blood coagulation FX, support further exploration of species D Ads as alternative oncolytic adenoviruses against multiple types of cancer.


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