Albumin pasteurization

PPV was also extracted with chloroform, but chloroform extraction had little effect on PPV inactivation during albumin pasteurization (Fig. 7). These results are comparable to previous reports of only l-21ogio Minute Virus of Mice, another parvovirus, inactivation after 6 hr of pasteurization in 1% albu-min.f Thus, heat stability during pasteurization... 

Lipoproteins may denature on heating and if present during pasteurization can result in the formation of haze or turbidity in the final product. This material was removed traditionally by filtration through asbestos (qv) sheets (6) however, health hazards associated with asbestos have led to its replacement by alternative filter materials (23,37,193). These media have been less effective than asbestos and further measures have been required to ensure the visual clarity of albumin products, eg, further filtration developments for Hpid removal (194), preferential denaturation of contaminants using in-process heat treatment, and anion-exchange chromatography (49). 

Monoclate P Plasma Pasteurization, monoclonal antibody Albumin... 

Column Chromatography. Sepharose beads containing covalently linked gangliosides (0.2 ml packed volume) were placed into a pasteur pipette containing a small amount of glass wool. Columns were washed with HEM containing 50 ug/ml bovine serum albumin (3 ml). Interferon solutions in MEM-albumin (1 ml) were placed on the columns, which were eluted with MEM-albumin at a flow rate of no more than one drop per minute. Fractions of 1 ml were collected and interferon titers determined in each fraction after serial two-fold dilution. Columns onto which mouse fibroblast interferon had been loaded, were eluted with MEM-albumin first, then with 0.07 M N-acetylneuraminyl lactose at pH 2. 

Prime solutions used during cardiopulmonary bypass, prepared with either pasteurized human albumin or fresh-frozen plasma, were found to have low TAC, which may increase oxidative stress in neonates undergoing cardiopulmonary bypass (M26). 

Apply a small drop of the bovine albumin solution prepared in concentrated bromophenol blue solution by means of a Pasteur pipet above the sample well as indicated in Fig. la, in OTdcr to follow the migration in the plate. 

Sodium caprylate (sodium octoate) has antifungal properties, but it is also used to improve the stability of albumin solution against the effects of heat. Albumin solution can be pasteurized by heating at 60°C for 10 h in the presence of sodium caprylate. Acetyl tryptophanate sodium is also added to albumin formulations. 

Plasma-derived therapeutic proteins are parenteral biologies that are purified on an industrial scale. All biologies derived from human sources, such as plasma, carry the risk of viral contamination. Thus, in order to market a medicinal product derived from human plasma, manufacturers must assure the absence of specific viral contamination. Virus validation studies are performed to evaluate the capacity of a manufacturing process to remove viral contaminants. Virus clearance across three different terminal inactivation steps, low pH incubation of immunoglobulins (IgG), pasteurization of albumin, and freeze dry/dry heat treatment of plasma-derived products (Factor VIII and Protein G), is discussed in this article. The data show that, like all other upstream virus reduction steps, the methods used for terminal inactivation are process and product dependent, and that the reduction factors for an individual step may be overestimated or underestimated due to inherent limitations or inadequate designs of viral validation studies. 

The data discussed here are for Plasbumin -25, which is purified from Fraction V paste and consists of 23.5 /o-26.5 /o protein, of which no less than 96.5%o is albumin. The preparation is stabilized with 0.02 M sodium caprylate and 0.02 M acetyltryptophan and contains 145mEq/L sodium. For the virus clearance experiments, virus was spiked into albumin, pH 6.4-7.4, and the solution was heated at 60°C for 10 hr. Aliquots for virus titration were removed as soon as virus was added (preheat), when the temperature of the solution reached 60° C (Ohr) and at various times during the pasteurization cycle. Unheated albumin and HBSS were also spiked to the same dilution with virus and tested as positive controls. 

Fig. 4 Kinetics of virus inactivation during pasteurization of 25% albumin. (A) HIV-1, (B) PRV, (C) BVDV, (D) Reo, (E) PPV, and (F) HAV. Virus was spiked into albumin and an aliquot was removed for immediate titration (t = Preheat). Timing of the pasteurization cycle started when the temperature reached 60° C t — Ohr). Unheated albumin and Hanks Balanced Salt Solution (HBSS) were also spiked and incubated at 5°C, as positive controls. Aliquots for virus titration were removed at various times during pasteurization (closed circles = HBSS, 5°C, closed triangles = 25% albumin, 5°C, closed squares = 25% albumin, 60°C, dashed line, no symbol = virus detection limit).

In summary, pasteurization is effective for inactivation of many enveloped and non-enveloped viruses but their kinetics of inactivation are different. In the experiments with 25 /o albumin, enveloped viruses were below detection after heating for 5 hr, leaving a wide margin of safety. In contrast, non-enveloped virus reduction was slower and required the entire 10 hr of heating. Temperature, time, protein concentration, and possibly stabilizers were critical parameters for virus inactivation. 

Table 3 Summary of virus reduction during pasteurization of 25% albumin...

Fig. 5 Effect of (A) pH, (B) temperature, and (C) protein concentration on PPV and HAV inactivation during pasteurization of 25% albumin. Methods were as described in Fig. 4, except different pH, temperature, or protein concentrations were tested.

Fig. 7 Effect of chloroform extraction on virus inactivation during pasteurization in albumin. For these experiments, the virus spike was divided into half. One-half was extracted with an equal volume of chloroform while the other-half was prepared as usual. The untreated and chloroform extracted virus were then used as virus spike in pasteurization experiments as described in Fig. 4.

The results from the albumin studies demonstrated that virus selection (e.g., HM175/18f and HM175/24a) and preparation (e.g., chloroform extracted and untreated virus) were just as important as the process conditions (e.g., protein concentration and temperature) in determining the outcome of virus reduction during pasteurization. Since laboratory adapted viruses and naturally occurring viruses may differ in their sensitivity to physico-chemical treatments, the results observed with model viruses must be carefully interpreted before they can be extrapolated to relevant viruses of concern. 

The transmission of viral infections via albumin can be eliminated through pasteurization, and albumin treated in this way has an unblemished safety record in this regard, although there is little information on the safety of albumin with respect to hepatitis A and parvovirus (5). The production process excludes transmission of viruses such as hepatitis B and C and HIV (6). There have been no cases of HIV transmission attributed to this type of product, although many batches are known in retrospect to have been derived from HIV-contaminated pools (23). 

LI. Lapresle, C., Etude de la degradation de la s6rum albumine humaine par un extrait de rate de lapin. Ann. Inst. Pasteur 89, 654-665 (1955). 

Humate-P Plasma monoclonal antibody Pasteurization Albumin, vWF... 

Gi/mol), 2.5 p,g bovine serum albumin, 100 mU P-hexosaminidase A, and up to 25 p.1 of the suitably diluted activator sample in a total volume of 40 (il mM citrate buffer, pH 4.0, and is incubated for 1 -4 h at 37°C. Samples are then transferred to an ice bath and loaded onto 1 ml columns of DEAE-cellulose (in Pasteur pip>ettes) that have been washed with distilled water. Liberated [ H]A-acetylgalactosamine is eluted with 2 x 1 ml of a 1 mM aq A-acetylgalactosamine solution. The combined effluents are collected in scintillation vials, and after addition of 10 ml scintillation fluid, their radioactivity is measured. Blanks run with water instead of activator solution are subtracted. 

In 1929, Michel A. Macheboeuf (1900-1953), working at the Pasteur Institute in Paris, was the first to isolate and characterise the a-lipoprotein from the serum ofhorse blood. [357] The American biochemist Edwin Josef Cohn (1892-1953) succeeded in separating human blood plasma into different fractions. During the Second World War he developed at the Harvard Medical School for the American forces industrial processes for the production of serum albumin, y-globulin, fibrinogen and fibrin. These were urgently needed for the treatment of the wounded. In the course of these studies, he also isolated and characterised two different lipid fractions from human blood serum. 

This is a test to distinguish sterilized milk from pasteurized milk. During sterilization, all the albumin is precipitated. So, in the test the filtrate from an ammonium sulfate precipitation should remain clear on heating, indicating that no albumin was present in solution and the milk had therefore been sterilized. 

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