Differentiation between thermophilic Campylobacter species by species-specific antibodies

An assay has been designed for the identification of NCAM-binding proteins present in an NP-40 detergent extract of brain membranes. This method, which is capable of analyzing both heterophilic and homophilic interactions, uses species-specific antibodies against NCAM in combination with radioiodination, so that after unlabeled chicken and iodinated frog brain membrane proteins were allowed to interact, the chicken NCAM could be specifically isolated by immunoaffinity adsorption. The radiolabeled frog proteins coisolated with chicken NCAM were then characterized by one- and two-dimensional gel electrophoresis in combination with immunoblotting. The only detectable NCAM-binding proteins were identified as the 140- and 180-kD forms of NCAM. The presence and absence of polysialic acid on NCAM did not change the amount or nature of the frog proteins immunopurified under these conditions. As an alternative for detecting heterophilic ligands, a simplified immunoprecipitation method was employed using either iodine or sulfate radiolabels. Again under these conditions only NCAM was detected. These results are consistent with the hypothesis that the major binding protein for NCAM is NCAM itself, and suggest that differences in polysialic acid content do not directly alter the properties of NCAM's homophilic binding site.

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Campylobacter Contamination during Poultry Slaughter in Belgium

Journal of Food Protection ◽

10.4315/0362-028x-69.1.27 ◽

2006 ◽

Vol 69 (1) ◽

pp. 27-33 ◽

Cited By ~ 35

Author(s):

G. RASSCHAERT ◽

K. HOUF ◽

J. VAN HENDE ◽

L. de ZUTTER

Keyword(s):

Alimentary Tract ◽

Fragment Length Polymorphism ◽

Pulsed Field Gel Electrophoresis ◽

Species Level ◽

Campylobacter Coli ◽

Flagellin Gene ◽

Thermophilic Campylobacter ◽

Typing Methods ◽

Campylobacter Species ◽

Campylobacter Lari

The relation between internal carriage and surface contamination with thermophilic Campylobacter species in broilers was examined by molecular typing methods. Samples from 39 flocks were collected in three Belgian poultry slaughterhouses. From each flock, crop swabs before slaughter and intestines and neck skins during slaughter were collected. A total of 309 isolates were identified at species level and further characterized by flagellin gene A PCR/restriction fragment length polymorphism and pulsed-field gel electrophoresis. Isolates were identified as Campylobacter jejuni (90%), Campylobacter coli (8.7%), and Campylobacter lari (2.2%), and 27 genotypes could be distinguished by combining the two molecular methods. Seventy-two percent of the flocks arriving at the abattoir were colonized with campylobacters. After slaughter, 79% of the flocks had contaminated neck skins. In six flocks, genotypes isolated from the neck skins were also found in the alimentary tract from previously slaughtered flocks. Four of these flocks were initially free of Campylobacter. These four flocks might have had no contaminated carcasses after logistic slaughtering.

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Production of species-specific monoclonal antibodies that react with surface components on zoospores and cysts of Phytophthora nicotianae

Canadian Journal of Microbiology ◽

10.1139/w98-120 ◽

1998 ◽

Vol 44 (12) ◽

pp. 1161-1170 ◽

Cited By ~ 11

Author(s):

A V Robold ◽

A R Hardham

Keyword(s):

Monoclonal Antibodies ◽

Cell Lines ◽

Phytophthora Cinnamomi ◽

Phytophthora Nicotianae ◽

The Other ◽

Hybridoma Cells ◽

Enzyme Linked Immunosorbent Assay ◽

Specific Antibodies ◽

Hybridoma Cell Lines ◽

Species Specific

Monoclonal antibodies were generated against components on the surface of zoospores and cysts of the Oomycete, Phytophthora nicotianae, with the aim of obtaining antibodies diagnostic for this species of plant pathogen. A dipstick version of an enzyme-linked immunosorbent assay was used to screen hybridoma cell lines produced by following a coimmunization protocol in which a mouse was immunized with Phytophthora nicotianae cysts mixed with murine antisera raised against cysts of Phytophthora cinnamomi and Phytophthora cryptogea. Of the nine hybridoma cells lines which remained positive, five produced antibodies that reacted with species-specific epitopes on the surface of the spores. Immunofluorescence, immunogold, and immunoblot labelling showed that three of the five species-specific antibodies reacted with a polypeptide of relative molecular mass greater than 205 kDa which was distributed over the entire zoospore surface, including that of the two flagella. These antibodies also labelled the surface of cysts to varying degrees. The other two species-specific antibodies bound to the shaft of tubular mastigonemes that form two rows on the anterior flagellum. In immunoblots, one of these antibodies recognised a 40-kDa glycoprotein. Antibodies produced by the other four hybridoma cell lines reacted with all Phytophthora and Pythium species tested. The results (i) showed that the coimmunization technique effectively produced antibodies directed towards components specific for Phytophthora nicotianae in the presence of antigens common to many Phytophthora species, and (ii) revealed for the first time the biochemical nature of molecular constituents of flagellar mastigonemes in the Oomycetes.Key words: cell surface, flagella, immunodiagnostics, mastigonemes, monoclonal antibodies.

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Method-Dependent Variability in Determination of Prevalence of Campylobacter jejuni and Campylobacter coli in Canadian Retail Poultry

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-133 ◽

2014 ◽

Vol 77 (10) ◽

pp. 1682-1688 ◽

Cited By ~ 9

Author(s):

CATHERINE D. CARRILLO ◽

DANIEL PLANTE ◽

IRÈNE IUGOVAZ ◽

ROBYN KENWELL ◽

GHISLAINE BÉLANGER ◽

...

Keyword(s):

Campylobacter Coli ◽

Testing Methods ◽

Poultry Products ◽

Thermophilic Campylobacter ◽

Microbiological Methods ◽

Bacterial Gastroenteritis ◽

Campylobacter Species ◽

Raw Poultry ◽

Campylobacter Spp

Campylobacter is the most frequent cause of bacterial gastroenteritis in Canada, and the illness is commonly associated with poultry consumption. Whereas Canadian retail poultry is often contaminated with campylobacters, studies on the prevalence of this organism are inconsistent due to variability in sampling and microbiological methodology. To determine the current microbiological status of Canadian poultry, and to evaluate two commonly used microbiological methods, 348 raw poultry samples were collected at retail across Canada over a period of 3 years (2007 to 2010) and were analyzed for the presence of thermophilic Campylobacter species. The overall prevalence of Campylobacter spp. was found to be 42.8% by a combination of the two testing methods, with 33.9% of the samples positive for C. jejuni, 3.7% of the samples positive for C. coli, and 5.2% of the samples positive for both. Variability in Campylobacter spp. prevalence was observed in samples obtained from different regions across Canada and from poultry with or without skin, but this was not statistically significant. In co-contaminated samples, C. jejuni was preferentially recovered from Preston agar compared with mCCDA and Campy-Cefex agar, with an increase in recovery of C. coli on all selective media after 48 h of enrichment. A subset of 214 of the poultry rinses were analyzed by both Health Canada's standard method, MFLP-46 (enrichment in Park and Sanders broth), and a second method requiring enrichment in Bolton broth. Significantly more positive samples were obtained with the MFLP-46 method (40.6%) than with the alternate method (35.0%). This improved recovery with MFLP-46 may be due to the omission of cycloheximide from this method. These results demonstrate that determination of prevalence of Campylobacter spp. on poultry products may be significantly impacted by the choice of microbiological methods used. Canadian poultry continues to be a source of exposure to Campylobacter spp.

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