[PMC free article] [PubMed] [CrossRef] [Google Scholar] 20. 81% of group II dogs. In contrast, 24/26 group III dogs were not reactive to any immunodominant protein. In this study, the sensitivity and diagnostic accuracy of SA2 WB were higher than those of SA2 IFA testing. Some SA2 immunodominant proteins were recognized by dogs experimentally and naturally infected with spp. other than PCR-positive dogs (IFA antigens, including three strains, did not substantially improve the sensitivity (10). Thus, in the clinical setting, negative IFA results should be interpreted with caution. Western blotting (WB) has been used for the serodiagnosis of bartonelloses in humans; however, the utility of WB for the serodiagnosis of canine bartonelloses has not been critically investigated. A study investigating the utility of AM-2099 WB using serum samples from 92 human patients clinically AM-2099 suspected of cat scratch disease (CSD) documented a higher sensitivity of WB (53.5%) than of IFA (28.3%) (12). Investigators reported a 100% sensitivity of WB when it was used to diagnose blood culture-negative endocarditis in humans (3). We hypothesized that WB would be more sensitive than the IFA for the serodiagnosis of bartonelloses in dogs. Our three specific objectives were (i) to define immunodominant proteins recognized by sera from dogs experimentally and naturally infected with spp., (ii) AM-2099 to characterize the WB patterns that could be used for the serodiagnosis of canine bartonelloses, and (iii) to compare the sensitivity and the specificity of WB and IFA. MATERIALS AND METHODS Group I (10 dogs experimentally infected with spp.). Sera from dogs that were inoculated intradermally with blood agar plate-grown spp. as described previously (13) were provided by Bruno Chomel, School of Veterinary Medicine, University of California, Davis, CA. This study was approved by the UC Davis Institutional Animal Care and Use Committee (13). In brief, 6 adult beagles were inoculated with (strain 94022, isolated from a cat experimentally infested AM-2099 with fleas). Two dogs each were intradermally infected with inocula of 1 1.1??109 CFU/ml, 6.3??107 CFU/ml, and 2.4??106 CFU/ml. Two dogs receiving 6.3??107 CFU/ml were reinoculated with strain 94022 at 6.6??107 CFU/ml at 40?days after the initial inoculation. Two beagles were inoculated with subsp. type II JV15-2 (strain Coyote 15). After 7?months, two of the (strain Coyote 004). Prior to the initial inoculation, all dogs were PCR negative and seronegative and seroconverted within 2?weeks postinoculation. Dogs inoculated with subsp. type II and spp. for which dogs may be reservoirs, became bacteremic, whereas blood cultures were negative for spp. were used in this study. Sera from eight time points were tested (Table 1). TABLE 1 Patterns of SA2 protein recognition among 10 group I dogsSA2 WB banding pattern(s) (kDa) in dogs experimentally inoculated with spp.subsp. type II/7.6 10729292941, 37, 29233, 124, 94, 56, 41, 37, 29, 22, 13233, 124, 94, 56, 41, 37, 29, 22, 13NA94, 56, 41, 37, 29, 136GCB9subsp. type II/7.6 107NoneNone13183, 56, 29, 13183, 56, 29, 13, 10183, 56, 29, 13, 10NA183, 56, 29, 136GCB10spp. Entries for dogs inoculated with are unshaded, entries for dogs inoculated with subsp. genotype II are shaded light gray, and entries for dogs inoculated with are shaded dark gray. Two dogs (dogs 6GCB4 and 6GCB7) were reinoculated with the same strain, strain 94022, at 6.6??107 CFU/ml at 40?days after the initial inoculation. p.i., postinoculation; NA, not available. bDogs that had previously been inoculated (7?months earlier) with PCR-positive naturally infected dogs). Serum samples from 36 naturally exposed PCR-positive dogs, 34 of which were reported on in a previous study (10), were tested by WB. Based upon PCR amplification/DNA.
