Search results for "Capsid Proteins"
showing 10 items of 136 documents
Insights in ChAdOx1 nCoV-19 vaccine-induced immune thrombotic thrombocytopenia
2021
Abstract SARS-CoV-2 vaccine ChAdOx1 nCoV-19 (AstraZeneca) causes a thromboembolic complication termed vaccine-induced immune thrombotic thrombocytopenia (VITT). Using biophysical techniques, mouse models, and analysis of VITT patient samples, we identified determinants of this vaccine-induced adverse reaction. Super-resolution microscopy visualized vaccine components forming antigenic complexes with platelet factor 4 (PF4) on platelet surfaces to which anti-PF4 antibodies obtained from VITT patients bound. PF4/vaccine complex formation was charge-driven and increased by addition of DNA. Proteomics identified substantial amounts of virus production-derived T-REx HEK293 proteins in the ethyle…
Unraveling the role of the secretor antigen in human rotavirus attachment to histo-blood group antigens
2019
25 Páginas, 7 figuras, 2 tablas
Development of type-specific and cross-reactive serological probes for the minor capsid protein of human papillomavirus type 33.
1993
Human papillomavirus type 33 (HPV33) is associated with malignant tumors of the cervix. In an attempt to develop immunological probes for HPV33 infections, antisera against various bacterial fusion proteins carrying sequences of the minor capsid protein encoded by L2 were raised in animals. Antigenic determinants on the HPV33 L2 protein were identified by using truncated fusion proteins and were classified as type specific or cross-reactive with respect to HPV1, -8, -11, -16, and -18. Cross-reactive epitopes map to amino acids 98 to 107 or to amino acids 102 to 112 and 107 to 117, respectively, depending on the fusion protein used for immunization. Antibodies directed toward these epitopes …
Complete genome analysis of contemporary G12P[8] rotaviruses reveals heterogeneity within Wa-like genomic constellation
2016
G12 rotaviruses are globally emergent rotaviruses causing severe childhood gastroenteritis. Little is known about the evolution and diversity of G12P[8] rotaviruses and the possible role that widespread vaccine use, globally, has had on their emergence. In Sicily, Italy, surveillance activity for rotaviruses has been conducted uninterruptedly since 1985, thus representing a unique observatory for the study of human rotaviruses in the pre- and post-vaccine era. G12 rotaviruses were first detected only in 2012 and between 2012 and 2014 they accounted for 8.7% of all rotavirus-associated infections among children, with peaks of 27.8% in 2012/2013 and 21% in 2014. We determined and analyzed the…
Prevalence of group C rotaviruses in weaning and post-weaning pigs with enteritis.
2006
Diarrheic fecal specimens collected from porcine herds were screened for the presence of group C rotaviruses using a reverse transcription-polymerase chain reaction (RT-PCR) assay. A total of 188 samples were tested and 54 were positive. When compiled these data with diagnostic results on group A rotaviruses and enteric caliciviruses we found that all but 5 group C rotavirus positive samples contained at least one additional virus. A subset of samples were subjected to nucleotide sequencing. The selected strains showed an unexpectedly wide range of nucleotide sequence heterogeneity (88.6-100%) to each other and to the reference porcine group C rotavirus strain, Cowden. The nucleotide sequen…
Genetic heterogeneity in the VP7 of group C rotaviruses.
2007
AbstractEvidence for a possible zoonotic role of group C rotaviruses (GCRVs) has been recently provided. To gain information on the genetic relationships between human and animal GCRVs, we sequenced the VP7 gene of 10 porcine strains detected during a large surveillance study from different outbreaks of gastroenteritis in piglets. Four GCRV strains were genetically related to the prototype GCRV porcine Cowden strain. A completely new VP7 genotype included 4 strains (344/04-7-like) that shared 92.5% to 97.0% aa identity to each other, but <83% to human GCRVs and <79% to other porcine and bovine GCRVs. A unique 4-aa insertion (SSSV or SSTI), within a variable region at the carboxy-terminus of…
Selection of single-chain antibodies against the VP8* subunit of rotavirus VP4 outer capsid protein and their expression in Lactobacillus casei.
2004
ABSTRACTSingle-chain antibodies (scFv) recognizing the VP8* fraction of rotavirus outer capsid and blocking rotavirus infection in vitro were isolated by phage display. Vectors for the extracellular expression inLactobacillus caseiof one of the scFv were constructed.L. caseiwas able to secrete active scFv to the growth medium, showing the potential of probiotic bacteria to be engineered to express molecules suitable for in vivo antirotavirus therapies.
Crystallization and Preliminary X-Ray Analysis of Rotavirus Protein VP6
1998
ABSTRACT As a first step to gain insight into the structure of the rotavirus virion at atomic resolution, we report here the expression, purification, and crystallization of recombinant rotavirus protein VP6. This protein has the property of polymerizing in the form of tubular structures in solution which have hindered crystallization thus far. Using a combination of electron microscopy and small-angle X-ray scattering, we found that addition of Ca 2+ at concentrations higher than 100 mM results in depolymerization of the tubes, leading to an essentially monodisperse solution of trimeric VP6 even at high protein concentrations (higher than 10 mg/ml), thereby enabling us to search for crysta…
Rotavirus-Specific Cytotoxic T Lymphocytes Recognize Overlapping Epitopes in the Amino-Terminal Region of the VP7 Glycoprotein
1999
Abstract Rotavirus-specific cytotoxic T lymphocytes (CTL) play an important role in the resolution of rotavirus infection. The outer capsid glycoprotein, VP7, elicits a class I MHC-restricted CTL response. Vaccinia virus recombinants expressing the VP7 genes from simian rotavirus SA11 (serotype G3) and from the RF strain of bovine rotavirus (serotype G6) were used to analyze the CTL activity to this antigen in BALB/c (H-2 d ) and C57BL/6 (H-2 b ) mice neonatally infected with homologous and heterologous rotaviruses. A vaccinia virus recombinant expressing the first amino-terminal 88 amino acids of VP7 was constructed and used to search for cross-reactive CTL against this region of the prote…
Heterogeneity and temporal dynamics of evolution of G1 human rotaviruses in a settled population.
2006
ABSTRACT A rotavirus sample collection from 19 consecutive years was used to investigate the heterogeneity and the dynamics of evolution of G1 rotavirus strains in a geographically defined population. Phylogenetic analysis of the VP7 gene sequences of G1P[8] human rotavirus strains showed the circulation of a heterogeneous population comprising three lineages and seven sublineages. Increases in the circulation of G1 rotaviruses were apparently associated with the introduction of novel G1 strains that exhibited multiple amino acid changes in antigenic regions involved in rotavirus neutralization compared to the strains circulating in the previous years. The emergence and/or introduction of G…