Search results for "recombinant"
showing 10 items of 1150 documents
New chimaeric hepatitis B virus core particles carrying hantavirus (serotype Puumala) epitopes: immunogenicity and protection against virus challenge
1999
Virus-like particles generated by the heterologous expression of virus structural proteins are able to potentiate the immunogenicity of foreign epitopes presented on their surface. In recent years epitopes of various origin have been inserted into the core antigen of hepatitis B virus (HBV) allowing the formation of chimaeric HBV core particles. Chimaeric core particles carrying the 45 N-terminal amino acids of the Puumala hantavirus nucleocapsid protein induced protective immunity in bank voles, the natural host of this hantavirus. Particles applied in the absence of adjuvant are still immunogenic and partially protective in bank voles. Although a C-terminally truncated core antigen of HBV…
Chimaeric HBV core particles carrying a defined segment of Puumala hantavirus nucleocapsid protein evoke protective immunity in an animal model
1998
Abstract Hantaviruses are rodent-born agents which are pathogenic in humans causing haemorrhagic fever with renal syndrome or hantavirus pulmonary syndrome. To induce a protective immunity against a European hantavirus (Puumala) we constructed chimaeric hepatitis B virus (HBV) core particles carrying defined fragments of the Puumala virus nucleocapsid protein. After immunisation of bank voles, the natural host of Puumala virus, with core particles possessing an insertion of the N-terminal part of Puumala virus nucleocapsid protein, four of five animals were protected against subsequent virus challenge. The results show that the major protective region of the nucleocapsid protein is located …
An amino-terminal segment of hantavirus nucleocapsid protein presented on hepatitis B virus core particles induces a strong and highly cross-reactive…
2004
AbstractPreviously, we have demonstrated that hepatitis B virus (HBV) core particles tolerate the insertion of the amino-terminal 120 amino acids (aa) of the Puumala hantavirus nucleocapsid (N) protein. Here, we demonstrate that the insertion of 120 amino-terminal aa of N proteins from highly virulent Dobrava and Hantaan hantaviruses allows the formation of chimeric core particles. These particles expose the inserted foreign protein segments, at least in part, on their surface. Analysis by electron cryomicroscopy of chimeric particles harbouring the Puumala virus (PUUV) N segment revealed 90% T = 3 and 10% T = 4 shells. A map computed from T = 3 shells shows additional density splaying out …
Pippin protein expression changes during cell differentiation
2008
PIPPin is a CSD-containing protein with the ability to interact both with mRNAs encoding histone variants and chromatin. A major fraction of chromatin-bound PIPPin is sumoylated and sumoylation seems to be controlled by thyroid hormones, both in vivo and in vitro. We studied its expression in different tissues and cell lines and even in tumor cells and found that, even if more expressed in the brain respect to other tissues of the adult rat, it is also expressed in brain tumors and in cell lines as different as kidney NRK cells and PC12. The expression of the protein is strongly increased by treatments that induce differentiation, such as treatment of PC12 with NGF. We also found an increas…
Combined Therapy of Interferon Plus Ribavirin Promotes Multiple Adaptive Solutions in Hepatitis C Virus
2009
Hepatitis C virus (HCV) presents several regions involved potentially in evading antiviral treatment and host immune system. Two regions, known as PKR-BD and V3 domains, have been proposed to be involved in resistance to interferon. Additionally, hypervariable regions in the envelope E2 glycoprotein are also good candidates to participate in evasion from the immune system. In this study, we have used a cohort of 22 non-responder patients to combined therapy (interferon alpha-2a plus ribavirin) for which samples obtained just before initiation of therapy and after 6 or/and 12 months of treatment were available. A range of 25-100 clones per patient, genome region and time sample were obtained…
The yeast inositol monophosphatase is a lithium- and sodium-sensitive enzyme encoded by a non-essential gene pair
1999
Inositol monophosphatases (IMPases) are lithium-sensitive enzymes that participate in the inositol cycle of calcium signalling and in inositol biosynthesis. Two open reading frames (YHR046c and YDR287w) with homology to animal and plant IMPases are present in the yeast genome. The two recombinant purified proteins were shown to catalyse inositol-1-phosphate hydrolysis sensitive to lithium and sodium. A double gene disruption had no apparent growth defect and was not auxotroph for inositol. Therefore, lithium effects in yeast cannot be explained by inhibition of IMPases and inositol depletion, as suggested for animal systems. Overexpression of yeast IMPases increased lithium and sodium toler…
Fine characterization of immunological mechanisms mediated by the major allergens of Parietaria judaica and by a hypoallergenic hybrid, rPjEDcys.
2015
Allergy is a hypersensitivity disease IgE-mediated, affecting more than 25% of the population. Actually the only curative treatment of allergies is Allergen-Specific Immunotherapy (SIT). Recombinant hypoallergenic allergen derivatives with reduced allergenic activity have been engineered to reduce side effects during SIT. Parietaria judaica (Pj) pollen contains two major allergens, Par j 1 and expressing disulphide bond variants of Par j 1 and Par j 2, was generated. The aim of this research project is to compare the immunological mechanisms activated by the major allergens of Pj and by rPjEDcys. In vitro analysis suggested that rPjEDcys has a reduced allergenity and maintains T cells react…
Lipid nanoparticles as delivery vehicles for the Parietaria judaica major allergen Par j 2
2011
Maria Luisa Bondì1,*, Giovanna Montana2,*, Emanuela Fabiola Craparo3, Roberto Di Gesù3, Gaetano Giammona3, Angela Bonura2, Paolo Colombo21Istituto per lo Studio dei Materiali Nanostrutturati, 2Istituto di Biomedicina ed Immunologia Molecolare, Consiglio Nazionale delle Ricerche, 3Laboratory of Biocompatible Polymers, Dipartimento di Scienze e Tecnologie Molecolari e Biomolecolari Stembio, Università di Palermo, Palermo, Italy *These authors contributed equally to this workAbstract: Parietaria pollen is one of the major causes of allergic reaction in southern Europe, affecting about 30% of all allergic patients in this area. Specific immunotherapy is the only…
Expression and subcellular targeting of canine parvovirus capsid proteins in baculovirus-transduced NLFK cells
2004
AbstractA mammalian baculovirus delivery system was developed to study targeting in Norden Laboratories feline kidney (NLFK) cells of the capsid proteins of canine parvovirus (CPV), VP1 and VP2, or corresponding counterparts fused to EGFP. VP1 and VP2, when expressed alone, both had equal nuclear and cytoplasmic distribution. However, assembled form of VP2 had a predominantly cytoplasmic localization. When VP1 and VP2 were simultaneously present in cells, their nuclear localization increased. Thus, confocal immunofluorescence analysis of cells transduced with the different baculovirus constructs or combinations thereof in the absence or presence of infecting CPV revealed that the VP1 protei…
Assembly of fluorescent chimeric virus-like particles of canine parvovirus in insect cells
2004
Canine parvovirus (CPV) is a small non-enveloped ssDNA virus composed of the viral proteins VP1, VP2, and VP3 with a T=1 icosahedral symmetry. VP2 is nested in VP1 and the two proteins are produced by differential splicing of a primary transcript of the right ORF of the viral genome. The VP2 protein can be further proteolytically cleaved to form VP3. Previous studies have shown that VP1 and VP3 are unnecessary for capsid formation and consequently, that VP2 alone is sufficient for assembly. We have hypothesized that insertion of the enhanced green fluorescent protein (EGFP) at the N-terminus of VP2 could be carried out without altering assembly. To investigate the possibility to develop flu…