Effects of Porcine Circovirus Type 2 and Porcine Reproductive and Respiratory Syndrome Virus Infection, Singular or Combined, on Swine Alveolar Macrophages 93-2313-B-002-043 93 8 1 94 7 31 PMWS (Postweaning multisystemic wasting syndrome, PCV2 PRRSV PMWS) (Porcine PCV2 PRRSV circovirus type 2, PCV2) TNF-αIL-8 IFN-α PCV2 FasL (Porcine reproductive and PMWS respiratory syndrome virus, PRRSV)PRRSV PCV2 PRRSV PCV2 PRRSV PCV2 PRRSV Abstract (AMs) Porcine circovirus 2 (PCV2) is currently considered the primary causative agent of IL-1βIFN-αIL-8 postweaning multisystemic wasting syndrome TNF-α (PMWS); however, porcine reproductive and PCV2 AMs IFN-α respiratory syndrome virus (PRRSV) has been PRRSV suggested as a co-factor needed for the full PCV2 AMs development of PMWS. Both viruses attack alveolar macrophage-derived neutrophil monocyte/macrophage lineage cells and are chemotactic factors II (AMCF-II)granulocyte suggested immunocompromised. In our previous colony-stimulating factor (G-CSF)monocyte study, we have demonstrated the effects of the chemotactic protein-1 (MCP-1)IL-8 infection of both viruses, singular or combined, PCV2 AMs on the infectious rate, viability, apoptosis, Fas ligand phagocytosis and microbial killing function of (FasL) swine alveolar macrophages (AMs). We also PCV2 AMs have proved the high level of interferon-α
induced by PCV2-infected AMs may cause a reduction in PRRSV replication and PRRSV-related AM dysfunction. In present study, we revealed that the levels of tumor necrosis alpha (TNF-α), interleukin 8 (IL-8), alveolar macrophage-derived neutrophil chemotactic factors II (AMCF-II), granulocyte colony-stimulating factor (G-CSF), monocyte chemotactic protein-1 (MCP-1), and a commonly known apoptotic inducer and also an inflammatory mediator, Fas ligand (FasL), were strongly up-regulated in PCV2-infected AMs. The enhanced expression levels of various inflammatory cytokines, chemokines and FasL in PCV2-infected AMs may contribute to the pathogenesis of interstitial pneumonia in pigs with PMWS. Moreover, a significant increase in the expression of FasL and a concurrent appearance of TNF-α, IL-8, and IFN-α were observed in PCV2 and PRRSV dually infected groups as compared with PCV2- or PRRSVinfected AMs. The result may contribute, at least partially, to the enhancement of PMWS in PRRSV co-infected cases and the pathogenesis of the full development of PMWS clinically. Keywords: Porcine circovirus 2 (PCV2), postweaning multisystemic wasting syndrome (PMWS), porcine reproductive and respiratory syndrome virus (PRRSV), swine alveolar macrophages (AMs), cytokine, chemokine PMWS (Porcine reproductive and respiratory syndrome virus; PRRSV) (Segales and Domingo, 2002) PCV2 PRRSV PMWS PCV2 (Harms et al., 2001; Rovira et al., 2002) PCV2 PRRSV Winkler Cheville (1987) 75% (alveolar macrophages; AMs) PCV2 AMs PCV2 PRRSV AMs PCV2 PRRSV AMs IL-1βIFN-αIL-8 TNF-α PCV2 AMs IFN-α PRRSV (Chang et al., 2005) PMWS (Rosell et al., 1999) TNF-α IL-1β (Dinarello, 2000) IL-8 (Baggiolini et al., 1994) (Postweaning MCP-1 multisystemic wasting syndrome ; PMWS) (Gerszten et al., 1999) IL-8, (Porcine circovirus type 2; PCV2) (alveolar macrophage-derived neutrophil chemotactic factors II; AMCF-II) T (regulated on activation
normal T-cell expressed and secreted; RANTES) PCV2 PRRSV (Yoshioka et al., 2004) AMs (Goodman et al., 1991) TNF-αIL-8 IFN-α FasL G-CSF PCV2 PRRSV (Zhang et al., 2000)GM-CSF ligand (Shen et PMWS al., 2004)MCP-1 MCP-2 PMWS PRRSV (Baier et al., PMWS 2004) PCV2 ELISA multiprobe ribonuclease protection assay (RPA) PCV2 AMs multiprobe TNF-α IL-1βIL-8 AMCF-II ribonuclease protection assay (RPA) GM-CSFG-CSFMCP-1MCP-2IL-8 RANTES RNA (messenger RNA) Fas (CD95)Fas ligand (FasL) RT-PCR Fas/FasL (Nakamura et al., 2004) Veterinary Microbiology (DosReis and Borges, 2003) (Chang et al., 2005) 酶 RT-PCR PCV2 PRRSV Fas FasL Baggiolini, M., Dewed, B., Moser, B., 1994. RPA PCV2 AMs Interleukin-8 and related chemotactic AMCF-II cytokines-cxc and CC chemokines. Adv. G-CSFMCP-1 IL-8 Immunol. 55, 97-179. IL-8 IFN-α Baier, R.J, Majid, A., Parupia, H., Loggins, J., PCV2 PRRSV Kruger, T.E., 2004. CC chemokine concentrations increase in respiratory distress FasL AMs syndrome and correlate with development of bronchopulmonary dysplasia. Pediatr. PMWS Pulmonol. 37, 137-148. Chang, H.W., Jeng, C.R., Liu, J.J., Lin, T.L., Chang, C.C., Chia, M.Y., Tsai, Y.C., Pang, V.F., 2005. Reduction of porcine reproductive and
respiratory syndrome virus (PRRSV) infection in swine alveolar macrophages by porcine circovirus 2 (PCV2)-induced interferon-alpha. Vet. Microbiol. (in press). Dinarello, C., 2000. Proinflammatory cytokines. Chest 118, 503-508. DosReis, G.A., Borges, V.M., 2003. Role of Fas-ligand induced apoptosis in pulmonary inflammation and injury. Curr. Drug. Targets. Inflamm. Allergy. 2, 161-167. Gerszten, R.E., Garcia-Zepeda, E.A., Lim, Y.C., Yoshida, M., Ding, H.A., Gimbrone, M.A., Jr., Luster, A.D., Luscinskas, F.W., Rosenzweig, A., 1999. MCP-1 and IL-8 trigger firm adhesion of monocytes to vascular endothelium under flow conditions. Nature 398, 718-723. Goodman, R.B., Forstrom, J.W., Osborn, S.G., Chi, E.Y., Martin, T.R., 1991. Identification of two neutrophil chemotactic peptides produced by porcine alveolar macrophages. J. Biol. Chem. 266, 8455-8463. Harms, P.A., Sorden, S.D., Halbur, P.G., Bolin, S.R., Lager, K.M., Morozov, I., Paul, P.S., 2001, Experimental reproduction of severe disease in CD/CD pigs concurrently infected with type 2 porcine circovirus and porcine reproductive and respiratory syndrome virus. Vet Pathol 38, 528-539. Nakamura, M., Matute-Bello, G., Liles, W.C., Hayashi, S., Kajikawa, O., Lin, S.M., Frevert, C.W., Martin, T.R., 2004. Differential response of human lung epithelial cells to fas-induced apoptosis. Am. J. Pathol. 164, 1949-1958. Rosell, C., Segales, J., Plana-Duran, J., Balasch, M., Rodriguez-Arrioja, G.M., Kennedy, S., Allan, G.M., McNeilly, F., Latimer, K.S., Domingo, M., 1999, Pathological, immunohistochemical, and in-situ hybridization studies of natural cases of postweaning multisystemic wasting syndrome (PMWS) in pigs. J Comp Pathol 120, 59-78. Rovira, A., Balasch, M., Segales, J., Garcia, L., Plana-Duran, J., Rosell, C., Ellerbrok, H., Mankertz, A., Domingo, M., 2002, Experimental inoculation of conventional pigs with porcine reproductive and respiratory syndrome virus and porcine circovirus 2. J Virol 76, 3232-3239. Segales, J., Domingo, M., 2002, Postweaning multisystemic wasting syndrome (PMWS) in pigs. A review. Vet Q 24, 109-124. Shen, L., Fahey, J.V., Hussey, S.B., Asin, S.N., Wira, C.R., Fanger, M.W., 2004. Synergy between IL-8 and GM-CSF in reproductive tract epithelial cell secretions promotes enhanced neutrophil chemotaxis. Cell. Immunol. 230, 23-32. Winkler, G.C., Cheville, N.F., 1987, Postnatal colonization of porcine lung capillaries by intravascular macrophages: an ultrastructural, morphometric analysis. Microvasc Res 33, 224-232. Yoshioka, S., Mukae, H., Sugiyama, K., Kakugawa, T., Sakamoto, N., Nakayama, S., Abe, K., Fujii, T., Kadota, J., Kohno, S., 2004. High-BAL fluid concentrations of RANTES in nonspecific interstitial pneumonia compared with usual interstitial pneumonia. Respir. Med. 98, 945-951. Zhang, P., Summer, W.R., Bagby, G.J., Nelson, S., 2000. Innate immunity and pulmonary host defense. Immunol. Rev. 173, 39-51.