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Nicola Boschetti

Publications and source records attributed to Nicola Boschetti.

7 recordsLinked to original sources
PubMed2006

Pathogen inactivation and removal procedures used in the production of intravenous immunoglobulins.

Patients with immunodeficiencies or some types of autoimmune diseases rely on a safe therapy with intravenous immunoglobulins (IVIGs) manufactured from human plasma, the only available source for this therapeutic. Since plasma is predisposed to contamination by a variety of blood-borne pathogens, ascertaining and ensuring the pathogen safety of plasma-derived therapeutics is a priority among manufacturers. State-of-the-art manufacturing processes provide a high safety standard by incorporating virus elimination procedures into the manufacturing process. Based on their mechanism these procedures are grouped into three classes: partitioning, inactivation, and virusfiltration.

Autoimmune Diseases↗
PubMed2006

Short regions of sequence identity between the genomes of human and rodent parvoviruses and their respective hosts occur within host genes for the cytoskeleton, cell adhesion and Wnt signalling.

Our understanding of the mechanism(s) of pathogenesis and persistence of vertebrate parvoviruses remains incomplete. With the recent availability of the complete genome sequences of human, rat and mouse, and the ability to search these sequences and to locate matches to exact genomic regions, further insight into the interaction of parvoviruses with their human and rodent hosts is possible. To determine the extent and nature of sequence identity between candidate parvoviruses and their respective hosts, blast searches of the genome sequences of adeno-associated virus, parvovirus B19, mouse parvovirus, the prototype strain and immunosuppressant variant of minute virus of mouse, Kilham rat virus and rat parvovirus were performed against the genome(s) of their respective hosts (human, rat and mouse) using the resources of the NCBI and the Celera Discovery System. Regions of identity and similarity were mapped to their precise location in their particular host genome. For each virus, between one and 12 identical regions were found. Each identical region was 17-26 nt and was generally found at multiple sites within the particular host genome. These identical regions were predominantly located in non-coding regions of particular host genes and in intergenic regions. The ontology of host genes in which identical regions were found for each of the nine virus-host interactions highlighted several pathways/processes, including the cytoskeleton, cell adhesion and Wnt signalling. Within each virus species, these homologous regions were highly conserved (100 % identity in 16 out of 23 alignments where more than one sequence was available). All of these aspects suggest a particular advantage to the viruses of the presence of these sequences.

Animals↗
PubMed2005

Virus safety of intravenous immunoglobulin: future challenges.

Patients with immunodeficiencies or some types of autoimmune diseases are dependent on safe therapy with intravenous immunoglobulins. State-of-the-art manufacturing processes provide a high safety standard by incorporating virus elimination procedures into the manufacturing process. Based on their mechanism, these procedures are grouped into three classes: partitioning, inactivation, and removal based on size. Because of current socioeconomic and ecological changes, emerging pathogens continue to be expected. Such pathogens may spread very quickly because of increased intercontinental traffic. Severe acute respiratory syndrome-coronavirus and the West Nile virus are recent examples. Currently, it is not possible to predict the impact such a pathogen will have on blood safety because the capacity for a globally coordinated reaction to such a threat is also evolving. The worst-case scenario would be the emergence of a transmissible, small, nonenveloped virus in the blood donor population. Examples of small nonenveloped viruses, which change host and tissue tropism, are discussed, with focus on parvoviridae. Although today's immunoglobulins are safer than ever, in preparation for future challenges it is a high priority for the plasma industry to proactively investigate such viruses on a molecular and cellular level to identify their vulnerabilities.

Animals↗
PubMed2004

Functional integrity of intravenous immunoglobulin following irradiation with a virucidal dose of gamma radiation.

Although intravenous immunoglobulins (IVIG) and other plasma therapeutics have had a relatively good safety record, improved methods for viral clearance are constantly being evaluated and incorporated into new manufacturing processes. Gamma irradiation has been used routinely to assure sterility of healthcare products and medical devices, but it has not been applied successfully as a viral inactivation method for biologics. We examine whether virucidal doses of gamma irradiation (50 kGy) can be delivered to a manufacturing intermediate form of IVIG, a fractionated plasma paste, with negligible effect on structural and functional integrity of purified IgG product. Immunoglobulins from paste were examined for radiation-induced damage by SDS-PAGE and ELISAs utilizing viral antigens specific for rubella, CMV and mumps. Fc domain integrity was assessed by immunoblotting, quantitatively comparing the binding of irradiated and non-irradiated materials to cell surface Fcgamma receptors, and by employing quantitative RT-PCR to study the kinetics of accumulation of mRNA for the immune modulatory cytokines IL-1alpha, IL-1beta, IL-4, IL-8, IFNgamma, and TNFalpha. The results demonstrate that Fab and Fc domains of IVIG remain essentially intact and functional after gamma irradiation to virucidal doses, suggesting that this method could be used to enhance the safety of IVIG products.

Antigens↗
PubMed2004

Different susceptibility of B19 virus and mice minute virus to low pH treatment.

BACKGROUND: Parvoviridae are small nonenveloped viruses that are known to be highly resistant to physico-chemical treatments. Because low pH is frequently applied to process intermediates or final products, the impact of such conditions on the human erythrovirus B19 (B19V) and the mouse parvovirus (mice minute virus, MMV) was assessed, which is often used as a model for B19V. Owing to the lack of a suitable cultivation and/or detection system for B19V no such data exist so far. STUDY DESIGN AND METHODS: Virus inactivation was monitored by decrease of infectivity and loss of capsid integrity. Infectious B19V was quantified by detection of virus-specific messenger RNA from Ku812Ep6 cells. To measure capsid integrity, endonucleases were added after exposure to low pH and the encapsidated (endonuclease-protected) virus DNA was quantified by real-time PCR. RESULTS: B19V was inactivated greater than 5 log after 2 hours at pH 4, whereas MMV was resistant over 9 hours. Infectivity data strongly correlated with data obtained by the endonuclease assay. Capsid disintegration was observed in immunoglobulin G as well as in different albumin solutions. Temperature and pH showed concerted impact on B19V capsid disintegration. CONCLUSION: Our data show that B19V is much more vulnerable toward low pH conditions than MMV. Together with the previously reported susceptibility of B19V toward wet heat conditions, low pH is the second treatment where erythrovirus B19V is less resistant than viruses from the parvovirus genus.

Animals↗
PubMed2003

Stability of minute virus of mice against temperature and sodium hydroxide.

Treatment with steam and/or dilute NaOH are commonly used techniques to disinfect manufacturing vessels and tools in the pharmaceutical industry. The aim of this procedure is sanitisation and inactivation of microbiological and viral contaminants. Here we describe the inactivation of the mouse parvovirus Minute Virus of Mice (MVM) under these conditions. Parvoviruses are known to be resistant to physico-chemical treatment and one representative of this family, the human parvovirus B19, is a potential contaminant of blood plasma. We show inactivation kinetics for MVM treated with wet-heat (70, 80, 90 degrees C) and with 0.01-1 M NaOH solutions (pH >/=11.9). Robust inactivation was only achieved at 90 degrees C for at least 10 min and in NaOH solutions of pH >/=12.8 (0.1 M NaOH). It was observed, that aggregation of viruses might protect viral particles from inactivation by NaOH. Therefore, appropriate sample preparation of spiking material is important for accurate simulation of the naturally occurring situation. The observed stability at pH 11.8 exceeds the previously reported upper limit of pH 9. Inactivation was due to disintegration of the viral capsid as assessed by accessibility of viral DNA for endonucleases.

Animals↗