Limited susceptibility of three different mouse (Mus musculus) lines to Porcine circovirus-2 infection and associated lesions.
Porcine circovirus associated disease (PCVAD), a major global problem for pork producers, is characterized microscopically by depletion and histiocytic replacement of follicles in the lymphoid tissues. The objectives of this study were to determine 1) if Porcine circovirus-2 (PCV-2) inoculated mice (Mus musculus) can develop PCV-2 associated lymphoid lesions and serve as a model for PCVAD, and 2) if differences in PCV-2 host susceptibility exist among mice lines. Three groups (n = 48/group) of 4-wk-old male mice were used: BALB/c, C57BL/6, and C3H/HeJ. A 2 x 2 factorial analysis was designed for each group using PCV-2 inoculation and keyhole limpet hemocyanin in incomplete Freund's adjuvant injections on day 0 and 7 as factors. Necropsies were performed on days 12, 17, 22, 27, 32, and 37. Serum samples collected at each necropsy tested negative for anti-IgG PCV-2 antibodies in all mice at all time points by 2 different PCV-2 enzyme-linked immunosorbent assays (ELISA). The PCV-2 DNA was detected by polymerase chain reaction (PCR) in 93% (100/108) of tissues and 42.6% (46/108) of serum samples from PCV-2-inoculated mice from days 12 to 37. Microscopic lesions consistent with PCV-2 infection were not observed in any mice and PCV-2 DNA and PCV-2 antigen were not detected in tissues by in-situ-hybridization or immunohistochemistry assays, respectively. Based on incidence of PCV-2 DNA in serum samples, the C57BL/6 mouse line was more resistant to PCV-2 infection than the other lines. The results indicate the mouse model likely has limited utility to advance understanding of the pathogenesis of PCV-2 associated lesions, but mice could potentially be important in the epidemiology of PCV-2.
Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa 50011, USA. tanjaopr@iastate.edu
Tanja
T
Opriessnig
Abby R
AR
Patterson
Douglas E
DE
Jones
Nicole M
NM
Juhan
Xiang-Jin
XJ
Meng
Patrick G
PG
Halbur
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D016009:Chi-Square Distribution; D018173:Circoviridae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary*; D017925:Circovirus / Q000235:genetics / Q000276:immunology / Q000472:pathogenicity*; D004279:DNA, Viral / Q000097:blood; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D006433:Hemocyanins / Q000494:pharmacology; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008221:Lymphoid Tissue / Q000276:immunology / Q000821:virology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D016133:Polymerase Chain Reaction; D011897:Random Allocation; D013047:Specific Pathogen-Free Organisms; D013552:Swine; D013553:Swine Diseases / Q000097:blood / Q000276:immunology / Q000821:virology*
D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D004279:DNA, Viral; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin