jejuni 11168, inoculum prepared from the C. jejuni 11168 culture used to inoculate the mice Ku-0059436 cost in the fourth (final) passage, or tryptose soya broth. All mice were kept on the ~12% fat diet throughout this experiment and were necropsied
48 hours after inoculation. Enzyme-linked immunosorbant (ELISA) assays Plasma samples were assayed for C. jejuni-specific antibodies as previously described [40] using antigen prepared from non-adapted C. jejuni 11168. Histopathology Hematoxylin and eosin stained sections of the ileocecocolic junction of each mouse were scored as described previously on a scale of 0 to 44 [40]. For non-parametric statistical analysis, this scale was divided into grades of 0 (scores of 0 to 9), 1 (scores
of 10 to 19), and 2 (scores of 20 to 44). Statistical analysis Cluster analysis based on DNA sequences of housekeeping loci of the C. jejuni strains utilized sequence data from selleck the Campylobacter jejuni Multi Locus Sequence Typing website http://pubmlst.org/campylobacter/[7] and data generated in our laboratory for strain NW. Alignment and clustering were performed with ClustalW2 http://www.ebi.ac.uk/Tools/clustalw/index.html#[70] using default parameters. Reference strains established by Wareing et al. [42] were also included. Clustering analysis of manually scored RFLP patterns was performed using the Cluster V0.1 calculator http://www2.biology.ualberta.ca/jbrzusto/cluster.php developed by John Brzustowski [71]. The Jaccard similarity coefficient and the Saitou and Nei neighbor-joining Ureohydrolase clustering method were used. Fisher’s exact test and the Freeman Halton extension of Fisher’s exact test were performed using the VassarStats calculator http://faculty.vassar.edu/lowry/VassarStats.html[72]. Kaplan Meier log rank survival analyses were performed using SigmaStat 3.1 (Systat Software, Port Richmond, CA). Gross pathology, histopathology, and ELISA data were analyzed using SigmaStat 3.1. The nonparametric Kruskal Wallis one-way ANOVA was
used for gross pathology and histopathology scores in the serial passage experiment. Scores for analysis of gross pathology data were assigned as follows: no gross pathology, 1; either enlarged ileocecocolic lymph nodes or thickened colon wall, 2; both enlarged ileocecocolic lymph nodes and thickened colon wall, 3; enlarged ileocecocolic lymph nodes, thickened colon wall, and bloody contents in lumen, 4. Kruskal Wallis nonparametric one-way ANOVA was performed on these scores; if a significant result was obtained, post hoc comparisons were made using Fisher’s exact test. For this test, the two-way table was cast so that mice with no gross pathology (score of 1) were compared to mice having all levels of gross pathology (scores 2, 3, and 4) combined; correction for multiple comparisons was done using the Holm-Šidák procedure [73]. Histopathology scores were analyzed as previously described [40].