Viral pharmacovigilance study of haemophiliacs receiving porcine factor VIII

Real-time PCR protocol for the detection of porcine parvovirus in field samples

This report describes a real-time polymerase chain reaction assay with SYBR Green for detection of a broad range of porcine parvoviruses (PPV) and accurate virus quantification in porcine tissues. The assay targets the VP2 gene of PPV and the porcine genomic c-myc gene for normalization. The detection limit of the SYBR Green reaction was shown to be equivalent to 6 x 10(0) to 6 x 10(1) PPV copies/reaction and the overall detection limit equivalent to 0.1 TCID(50)/100 microl. The assay was linear over a 10(7) dilution range of template concentrations. Other porcine pathogens involved in reproductive disorders such as porcine circovirus 2 (PCV-2), porcine reproductive and respiratory virus (PRRSV), Aujeszky's disease virus (PRV) and other parvoviruses such as feline parvovirus (FPV), canine parvovirus (CPV), minute virus of canines (MVC) and a human parvovirus (B19) were not detected by this assay.

Haemophilic factors produced by transgenic livestock: abundance that can enable alternative therapies worldwide

Haemophilia replacement factors, both plasma-derived and recombinant, are in relatively short supply and are high-cost products. This has stymied the study and development of alternative methods of administration of haemophilia therapy even in the most economically advanced countries, owing to the large amounts of material needed because bioabsorption and bioavailability of haemophilic factors can be less than 10% when using non-intravenous routes of delivery. There is therefore a need to increase access to therapy worldwide by decreasing the cost and increasing the abundance so that therapy can be achieved through simplified, alternative delivery methods. Transgenic livestock have been used to produce haemophilic factors in milk. Only the pig mammary gland has been shown to carry out the post-translational processing necessary to enable both the biological activity and long circulation half-life needed for therapeutic glycoproteins. Furthermore, the large amounts of recombinant protein that can be produced from pig milk make feasible the use of alternative delivery methods such as oral, intratracheal, subcutaneous, and intramuscular administration.

Treatment of patients with haemophilia and inhibitory antibodies

The development of inhibitory antibodies is a complication which arise in approximately 10% of patients with haemophilia A. The underlying genetic mutation is the single most important predisposing cause, although other risk factors have been identified. Periodic screening for inhibitors is a vital aspect of haemophilia care. The consequences of inhibitor development are very significant in terms of morbidity and cost. Several agents are now available for control of bleeding, but these are often very expensive. The most useful agents include recombinant activated factor VII, prothrombin complex concentrates and porcine factor VIII. It is possible to suppress antibody production with immune tolerance, which is successful in approximately 85% of cases and relapse is rare.