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Antigenic Properties (antigenic + property)
Selected AbstractsAntigenic properties of the GroEL-like protein of Campylobacter rectusMOLECULAR ORAL MICROBIOLOGY, Issue 1 2002D. Hinode The purpose of this study was to clarify the antigenic properties of the GroEL-like protein of Campylobacter rectus using a specific polyclonal antibody directed to the purified 64-kDa GroEL-like protein (pAb- CrGroEL), a polyclonal antibody directed to the Actinobacillus actinomycetemcomitans GroEL-like protein (pAb- AaGroEL) and a monoclonal antibody against the recombinant human HSP60 (mAb-HuHSP60). In SDS-PAGE/Western immunoblotting analysis, mAb-HuHSP60, pAb- CrGroEL and pAb- AaGroEL were found to react with the GroEL-like protein (64-kDa) present in all C. rectus strains. A 150-kDa protein in C. rectus ATCC 33238 also reacted strongly with pAb- CrGroEL. This 150-kDa protein was found to be present on the surface-associated material of bacterial cells, as determined by transmission electron microscopy and immunogold labelling of cells with pAb- CrGroEL. Analysis of the first 20 N -terminal amino acids of the sequence of the 150-kDa protein revealed a strong homology (80%) with the C. rectus surface layer (S-layer) protein. Investigation of the biochemical nature of antigenic determinants using periodic acid and proteolytic enzymes showed that the C. rectus GroEL-like protein possessed immunodominant epitopes in both peptide and carbohydrate chains, and that the immunoreactive determinants of the 150-kDa protein belonged to carbohydrate. These results suggest that the GroEL-like protein and the S-layer protein of C. rectus may share the same carbohydrate epitopes. [source] ADAM-HCV, a new-concept diagnostic assay for antibodies to hepatitis C virus in serumFEBS JOURNAL, Issue 17 2001Olga Minenkova We screened phage libraries using sera from noninfected individuals and patients infected by hepatitis C virus (HCV). By applying different selection and maturation strategies, we identified a wide collection of efficient phage-borne ligands for HCV-specific antibodies. The selected ligands retained their antigenic properties when expressed as multimeric synthetic peptides. Peptides that mimic several immunodominant epitopes of the virus were used to develop a novel type of diagnostic assay which efficiently detects antibodies to HCV in serum. This type of analysis provides a conclusive diagnosis for many patients identified as indeterminate according to presently available serological assays. [source] Ultrastructural and antigenic properties of neural stem cells and their progeny in adult rat subventricular zoneGLIA, Issue 2 2009Alexandre I. Danilov Abstract Neural stem cells (NSCs) in the subventricular zone (SVZ) continuously generate olfactory bulb interneurons in the adult rodent brain. Based on their ultrastructural and antigenic properties, NSCs, transient amplifying precursor cells, and neuroblasts (B, C, and A cells, respectively) have been distinguished in mouse SVZ. Here, we aimed to identify these cell types in rat SVZ ultrastructurally and at the light microscopy level, and to determine the antigenic properties of each cell type using gold and fluorescence immunolabeling. We found astrocytes with single cilia (NSCs, correspond to B cells) and neuroblasts (A cells). We also observed mitotic cells, ependymal cells, displaced ependymal cells, and mature astrocytes. In contrast, transient amplifying precursor cells (C cells) were not detected. The NSCs and neuroblasts had epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor alpha (PDGFR,) expressed on the ciliary apparatus and were the only cell types incorporating the proliferation marker BrdU. Throughout mitosis, EGFR and PDGFR, were associated with the microtubule of the mitotic spindle. Ependymal and displaced ependymal cells also expressed EGFR and PDGFR, on their cilia but did not incorporate BrdU. Our findings indicate that the NSCs in adult rat SVZ give rise directly to neuroblasts. During mitosis, the NSCs disassemble the primary cilium and symmetrically distribute EGFR and PDGFR, among their progeny. © 2008 Wiley-Liss, Inc. [source] Adverse drug reactions to biologicsJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 6 2010Kathrin Scherer Summary The use of biologics has rapidly expanded since the introduction of the first diagnostic antibodies; they are now widely employed in oncology, autoimmune disorders, inflammatory diseases and transplantation medicine. Their widespread use has resulted in an increase in adverse drug reactions. Adverse effects result from both direct pharmacological actions and immunological actions, as well as through induction of a specific immune response. The nomenclature, particularly of the monoclonal antibodies, identifies the target structure and organ as well as the species of origin, which then helps predict their effects and antigenic properties. Depending on the extent of foreign protein, anti-allotypic or anti-idiotypic antibodies with or without neutralizing properties may be induced. Adverse drug reactions from biologics often depend on the target and may be explained by activation or inhibition of particular cytokine pathways. Adverse drug reactions are classified by their pathomechanism, which enhances understanding of the pathogenesis and facilitates both allergologic diagnostic measures and planning of premedication in future treatments. This review emphasizes immunostimulatory and hypersensitivity reactions. [source] Genetic and phenotypic diversity of echovirus 30 strains and pathogenesis of type 1 diabetesJOURNAL OF MEDICAL VIROLOGY, Issue 7 2007A. Paananen Abstract Several enterovirus serotypes should be considered as potentially diabetogenic. The capacity of an enterovirus to kill or impair the functions of human ,-cells can vary among the strains within a given serotype as shown previously for echovirus 9 and 30 (E-30). The evolution of E-30 has also shown patterns correlating with the global increase of type 1 diabetes incidence. In the present study, antigenic properties of a set of E-30 isolates were investigated and the results correlated with the previously documented ,-cell destructive phenotype of the strains, or to genetic clustering of the strains. No simple correlation between the three properties was observed. A full-length infectious clone was constructed and sequenced from one of the isolates found to be most destructive to ,-cells (E-30/14916net87). Phylogenetic analyses demonstrated that this strain was closely related to the E-30 prototype strain at the capsid coding region while outside the capsid region prototype strains of several other human enterovirus B serotypes clustered more closely. This suggests that the relatively greater pathogenicity of the strain might be based on properties of the genome outside of the structural protein coding region. Neutralizing antibody assays on sera from 100 type 1 diabetic patients and 100 controls using three different E-30 strains did not reveal differences between the groups. This finding does not support a previous proposition of aberrant antibody responses to E-30 in diabetic patients. It is concluded that identification of the genetic counterparts of pathogenicity of E-30 strains requires further studies. J. Med. Virol. 79:945-955, 2007. © 2007 Wiley-Liss, Inc. [source] Mumps virus strains isolated in Croatia in 1998 and 2005: Genotyping and putative antigenic relatedness to vaccine strainsJOURNAL OF MEDICAL VIROLOGY, Issue 5 2006antak Abstract Two mumps virus strains 9218/Zg98 and Du/CRO05 were isolated in two locations in Croatia in 1998 and 2005, respectively. Genetic characterization of these temporally distinct mumps virus isolates was carried out in order to determine their genotype and putative antigenic relatedness to mumps virus vaccine strains. Sequence analysis of the small hydrophobic (SH) gene revealed that isolate 9218/Zg98 shows less than 95% of similarity to any reference strain, thus representing a potential reference strain for a new genotype. Isolate Du/CRO05 clearly belongs to genotype G with the 97% of homology to the reference strain Glouc1/UK96. When compared to each other, the two Croatian strains have extremely low level of homology of only 89% indicating no relatedness between them. Putative antigenic properties of the HN protein of these two isolates were compared to different vaccine strains. The results reveal a higher level of homology of antigenic determinants to non-A genotype vaccine strains than to A genotype vaccine strain. J. Med. Virol. 78:638,643, 2006. © 2006 Wiley-Liss, Inc. [source] Antigenic properties of the GroEL-like protein of Campylobacter rectusMOLECULAR ORAL MICROBIOLOGY, Issue 1 2002D. Hinode The purpose of this study was to clarify the antigenic properties of the GroEL-like protein of Campylobacter rectus using a specific polyclonal antibody directed to the purified 64-kDa GroEL-like protein (pAb- CrGroEL), a polyclonal antibody directed to the Actinobacillus actinomycetemcomitans GroEL-like protein (pAb- AaGroEL) and a monoclonal antibody against the recombinant human HSP60 (mAb-HuHSP60). In SDS-PAGE/Western immunoblotting analysis, mAb-HuHSP60, pAb- CrGroEL and pAb- AaGroEL were found to react with the GroEL-like protein (64-kDa) present in all C. rectus strains. A 150-kDa protein in C. rectus ATCC 33238 also reacted strongly with pAb- CrGroEL. This 150-kDa protein was found to be present on the surface-associated material of bacterial cells, as determined by transmission electron microscopy and immunogold labelling of cells with pAb- CrGroEL. Analysis of the first 20 N -terminal amino acids of the sequence of the 150-kDa protein revealed a strong homology (80%) with the C. rectus surface layer (S-layer) protein. Investigation of the biochemical nature of antigenic determinants using periodic acid and proteolytic enzymes showed that the C. rectus GroEL-like protein possessed immunodominant epitopes in both peptide and carbohydrate chains, and that the immunoreactive determinants of the 150-kDa protein belonged to carbohydrate. These results suggest that the GroEL-like protein and the S-layer protein of C. rectus may share the same carbohydrate epitopes. [source] Effects of mutation at the D-JH junction on affinity, specificity, and idiotypy of anti-progesterone antibody DB3PROTEIN SCIENCE, Issue 9 2006Mingyue He Abstract The crystal structures of the Fab, fragment of the anti-progesterone monoclonal antibody DB3 and its complexes with steroid haptens have shown that the D-JH junctional residue TrpH100 is a key contributor to binding site interactions with ligands. The indole group of TrpH100 also undergoes a significant conformational change between the bound and unliganded states, effectively opening and closing the combining site pocket. In order to explore the effect of substitutions at this position on steroid recognition, we have carried out mutagenesis on a construct encoding a three-domain single-chain fragment (VH/K) of DB3 expressed in Escherichia coli. TrpH100 was replaced by 13 different amino acids or deleted, and the functional and antigenic properties of the mutated fragments were analyzed. Most substitutions, including small, hydrophobic, hydrophilic, neutral, and negatively charged side chains, were reduced or abolished binding to free progesterone, although binding to progesterone-BSA was partially retained. The reduction in antigen binding was paralleled by alteration of the idiotype associated with the DB3 combining site. In contrast, the replacement of TrpH100 by Arg produced a mutant that retained wild-type antibody affinity and idiotype, but with altered specificity. Significant changes in this mutant included increased relative affinities of 104 -fold for progesterone-3-carboxymethyloxime and 10-fold for aetiocholanolone. Our results demonstrate an essential role for the junctional residue H100 in determining steroid-binding specificity and combining site idiotype and show that these properties can be changed by a single amino acid substitution at this position. [source] |