Evaluation of the effects of porcine genogroup 1 torque teno virus in gnotobiotic swine.
OBJECTIVE
To determine whether porcine genogroup 1 torque teno virus (g1-TTV) can infect and cause disease in gnotobiotic swine.


METHODS
20 conventional baby pigs and 46 gnotobiotic baby pigs.


METHODS
Porcine g1-TTV was transmitted from conventional swine to gnotobiotic pigs via pooled leukocyte-rich plasmas (n=18) that had positive results for g1-TTV DNA. Bone marrow-liver homogenates that had positive results for torque teno virus (TTV) were used in 4 serial passages in gnotobiotic pigs (2 pigs/passage). A pathogenesis experiment was conducted with in vivo passages of g1-TTV in various groups of gnotobiotic pigs.


RESULTS
All g1-TTV inoculated pigs had no clinical signs but developed interstitial pneumonia, transient thymic atrophy, membranous glomerulonephropathy, and modest lymphocytic to histiocytic infiltrates in the liver after inoculation with the TTV-containing tissue homogenate; these changes were not detected in uninoculated control pigs or pigs injected with tissue homogenate devoid of TTV DNAs. In situ hybridization was used to identify g1-TTV DNAs in bone marrow mononuclear cells.


CONCLUSIONS
Analysis of these data revealed that porcine g1-TTV was readily transmitted to TTV-naïve swine and that infection was associated with characteristic pathologic changes in gnotobiotic pigs inoculated with g1-TTV. Thus, g1-TTV could be an unrecognized pathogenic viral infectious agent of swine. This indicated a directly associated induction of lesions attributable to TTV infection in swine for a virus of the genus Anellovirus.
Krakowka
Steven
S
Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, 43210, USA.
Ellis
John A
JA
D000818:Animals; D004266:DNA Virus Infections / Q000662:veterinary* / Q000821:virology; D005856:Germ-Free Life; D008168:Lung / Q000473:pathology; D008171:Lung Diseases / Q000662:veterinary / Q000821:virology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D013552:Swine; D013553:Swine Diseases / Q000821:virology*; D022783:Torque teno virus / Q000145:classification* / Q000235:genetics / Q000472:pathogenicity*