Validation of Bartonella henselae Western Immunoblotting for Serodiagnosis of Bartonelloses in Dogs.

Abstract

spp. are etiological agents of life-threatening zoonotic diseases in dogs worldwide. Due to the poor sensitivity of immunofluorescent-antibody assays (IFAs), a reliable serodiagnostic test for canine bartonelloses is of clinical importance. The utility of Western blotting (WB) for the serodiagnosis of canine bartonelloses has not been critically investigated. The objective of this study was to characterize WB immunodominant proteins that could be used to confirm a serodiagnosis of bartonelloses. Using agar-grownSan Antonio type 2 (SA2) whole-cell proteins, sera derived from four dog groups were tested by WB to assess immunodominant protein recognition patterns: group I consisted of 92 serum samples (10 preexposure and 82 postexposure serum samples) from 10 adult beagles experimentally inoculated withspp., group II consisted of 36 serum samples fromPCR-positive naturally infected dogs, group III consisted of 26 serum samples fromPCR-negative and IFA-negative dogs, and group IV consisted of serum samples from 8IFA-positive and 10IFA-positive dogs. Following experimental inoculation, 9 (90%) group I dogs were variably seroreactive to one or more of six specific immunodominant proteins (13, 17, 29, 50, 56, and 150 kDa). There was a strong but variable recognition of these proteins among 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 ofSA2 WB were higher than those ofSA2 IFA testing. SomeSA2 immunodominant proteins were recognized by dogs experimentally and naturally infected withspp. other thanAdditional research is necessary to more fully define the utility of WB for the serodiagnosis of canine bartonelloses.