[Virus inactivation in plasma fractions for therapeutic use]. / L'inactivation des virus dans les fractions plasmatiques à usage thérapeutique.

Methods to inactivate (or eliminate) viruses must be developed to ensure the safety of blood plasma fractions. For that purpose, dry or liquid heat treatment, solvent/detergent mixtures, beta-propiolactone/ultraviolet treatment, and chromatographic methods are the main procedures in use to date.

Large scale chromatographic purification of alpha 1-antitrypsin from human plasma supernatant II + III.

We describe a large-scale chromatographic method to purify alpha 1-antitrypsin (AAT) from human plasma supernatant II + III. Supernatant II + III was injected onto DEAE sepharose CL 6B to get an albumin-rich fraction as well as a fraction that contained about 45% AAT. This intermediate purity AAT fraction was further purified by size-exclusion chromatography on Sephacryl S-200. The product was heated in solution at 60 degrees C for 10 hours in the presence of a stabilizer to lower the risk of transmission of viral diseases. Purity of the AAT concentrate is over 85%; clinical testing of its safety and efficacy in the treatment of PiZ patients is underway.

Biochemical and biological properties of an alpha 1-antitrypsin concentrate.

alpha 1-Antitrypsin (AAT) has been purified from human plasma supernatant A (equivalent to COHN fraction II + III) by a large-scale chromatographic procedure involving anion-exchange adsorption on DEAE Sepharose CL-6B fast flow and size-exclusion chromatography on Sephacryl S-200. Before freeze-drying, the liquid concentrate was heat-treated at 60 degrees C for 10 h to reduce the risk of transmission of blood-born viral diseases. Using this procedure, AAT is recovered with 80-90% purity in 65-75% yield from supernatant A. The heterogeneity of AAT is preserved across the purification steps. In addition, purified AAT exhibits inhibitory activities against trypsin and elastase equivalent to that of the serum protein. The mean association rate constant for elastase was found as high as 2.15 X 10(5) M-1 s-1. Thus, purifying active AAT from supernatant A contributes to improving the availability of this protein which may be potentially useful in the treatment of hereditary emphysema.

[Preparation of a specific anti-cytomegalovirus immunoglobulin for intravenous injection]. / Préparation d'une immunoglobuline spécifique anti-cytomégalovirus injectable par voie intraveineuse.

In the industrialised countries of Europe about 60-70% of adults possess antibodies against cytomegalovirus. Primary infections or exacerbations of a latent infection are in most cases clinically asymptomatic in healthy patients. By way of contrast, attenuations in the immunological defence system: prematureness, pregnancy, the presence of malignant disease, immunosuppressive therapy, as well as massive transfusions of blood, are the commonest causes of a raised incidence of CMV infections often combined with severe clinical overt illness. Because a critical level of antibody is needed to prevent infection and disseminating, we have produced cytomegalovirus hyperimmune globulin for intravenous administration. They are prepared from plasmas of healthy blood donors on the basis of a high antibody level against cytomegalovirus. About 6% are selected by an ELISA procedure. Immunoglobulins, treated to ensure excellent intravenous acceptability, are lyophilized. The final product is found to have an anti-CMV antibody titer of 25 600, by the ELISA test, at a protein concentration of 5%. This CMV-immunoglobulin I.V. has 8 fold higher antibody content than do conventional immunoglobulin preparations. The first trials of prophylaxis and treatment of clinically apparent CMV infections are under study.