title: A novel bacterial symbiont in the nematode Spirocerca lupi.
abstract: BACKGROUND
  The parasitic nematode Spirocerca lupi (Spirurida: Thelaziidae), the canine esophageal worm, is the causative agent of spirocercosis, a disease causing morbidity and mortality in dogs. Spirocerca lupi has a complex life cycle, involving an obligatory coleopteran intermediate host (vector), an optional paratenic host, and a definitive canid host. The diagnosis of spirocercosis is challenging, especially in the early disease stages, when adult worms and clinical signs are absent. Thus, alternative approaches are needed to promote early diagnosis. The interaction between nematodes and their bacterial symbionts has recently become a focus of novel treatment regimens for other helminthic diseases.
  
  
  RESULTS
  Using 16S rDNA-based molecular methods, here we found a novel bacterial symbiont in S. lupi that is closely related to Comamonas species (Brukholderiales: Comamonadaceae) of the beta-proteobacteria. Its DNA was detected in eggs, larvae and adult stages of S. lupi. Using fluorescent in situ hybridization technique, we localized Comamonas sp. to the gut epithelial cells of the nematode larvae. Specific PCR enabled the detection of this symbiont's DNA in blood obtained from dogs diagnosed with spirocercosis.
  
  
  CONCLUSIONS
  The discovery of a new Comamonas sp. in S. lupi increase the complexity of the interactions among the organisms involved in this system, and may open innovative approaches for diagnosis and control of spirocercosis in dogs.
authors: Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel. yuvalgd@yahoo.com
authors: Yuval
authors: Y
authors: Gottlieb
authors: Eran
authors: E
authors: Lavy
authors: Meira
authors: M
authors: Kaufman
authors: Alex
authors: A
authors: Markovics
authors: Murad
authors: M
authors: Ghanim
authors: Itamar
authors: I
authors: Aroch
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D020585:Comamonas / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004283:Dog Diseases / Q000469:parasitology; D004285:Dogs; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D017205:Spirurida Infections / Q000469:parasitology / Q000662:veterinary; D013559:Symbiosis; D013802:Thelazioidea / Q000302:isolation & purification / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S