Twenty-two 4- to 5-week-old gnotobiotic pigs were intranasally inoculated with 10 TCID of porcine reproductive and respiratory syndrome virus (PRRSV) (Lelystad) and euthanized at different time intervals post-inoculation (p.i.). Bronchoalveolar lavage (BAL) cell populations were characterized, together with the pattern of virus replication and appearance of antibodies in the lungs. Total BAL cell numbers increased from 140×10 at 5 days p.i. to 948×10 at 25 days p.i. and remained at high levels until the end of the experiment. The number of monocytes/macrophages, as identified by monoclonal antibodies 74-22-15 and 41D3, increased two- to fivefold between 9 and 52 days p.i. with a maximum at 25 days p.i. Flow cytometry showed that the population of differentiated macrophages was reduced between 9 and 20 days p.i. and that between the same time interval, both 74-22-15-positive and 41D3-negative cells, presumably monocytes, and 74-22-15- and 41D3-double negative cells, presumably non-phagocytes, entered the alveolar spaces. Virus replication was highest at 7 to 9 days p.i., decreased slowly thereafter and was detected until 40 days p.i. Anti-PRRSV antibodies were detected starting at 9 days p.i. but neutralizing antibodies were only demonstrated in one pig euthanized at 35 days and another at 52 days p.i. The decrease of virus replication in the lungs from 9 days p.i. can be attributed to (i) shortage of susceptible differentiated macrophages, (ii) lack of susceptibility of the newly infiltrated monocytes and (iii) appearance of anti-PRRSV antibodies in the lungs. Neutralizing antibodies may contribute to the clearance of PRRSV from the lungs.


Article metrics loading...

Loading full text...

Full text loading...



  1. Cavanagh, D. (1997). Nidovirales: a new order comprising Coronaviridae and Arteriviridae.Archives of Virology 142, 629-633. [Google Scholar]
  2. Chen, Z., Rowland, R. R. R., Anderson, G. W., Palmer, G. A. & Plagemann, P. G. W. (1997). Coexistence in lactate dehydrogenase-elevating virus pools of variants that differ in neuropathogenicity and ability to establish a persistent infection.Journal of Virology 71, 2913-2920. [Google Scholar]
  3. Choi, C., Gustafson, K., Chinsakchai, S., Hill, H. & Molitor, T. (1994). Heterogeneity of porcine alveolar macrophage subpopulations: immune functions and susceptibility to PEARS virus. Proceedings of the 13th IPVS Congress, Bangkok, Thailand, pp. 97.
  4. Christopher-Hennings, J., Nelson, E. A., Hines, R. J., Nelson, J. K., Swenson, S. L., Zimmerman, J. J., Chase, C. C. L., Yaeger, M. J. & Benfield, D. A. (1995). Persistence of porcine reproductive and respiratory syndrome virus in serum and semen of adult boars.Journal of Veterinary Diagnostic Investigation 7, 456-464.[CrossRef] [Google Scholar]
  5. Collins, J. E., Benfield, D. A., Christianson, W. T., Harris, L., Hennings, J. C., Shaw, D. P., Goyal, S. M., McCullough, S., Morrison, R. B., Joo, H. S., Gorcyca, D. & Chladek, D. (1992). Isolation of swine infertility and respiratory syndrome virus (isolate ATCC VR-2332) in North America and experimental reproduction of the disease in gnotobiotic pigs.Journal of Veterinary Diagnostic Investigation 4, 117-126.[CrossRef] [Google Scholar]
  6. Drew, T. W., Meulenberg, J. J. M., Sands, J. J. & Paton, D. J. (1995). Production, characterization and reactivity of monoclonal antibodies to porcine reproductive and respiratory syndrome virus.Journal of General Virology 76, 1361-1369.[CrossRef] [Google Scholar]
  7. Duan, X., Nauwynck, H. J. & Pensaert, M. B. (1997a). Virus quantification and identification of cellular targets in the lungs and lymphoid tissues of pigs at different time intervals after inoculation with porcine reproductive and respiratory syndrome virus (PRRSV).Veterinary Microbiology 56, 9-19.[CrossRef] [Google Scholar]
  8. Duan, X., Nauwynck, H. J. & Pensaert, M. B. (1997b). Effects of origin and state of differentiation and activation of monocytes/macrophages on their susceptibility to PRRSV.Archives of Virology 142, 2483-2497.[CrossRef] [Google Scholar]
  9. Duan, X., Nauwynck, H. J., Favoreel, H. W. & Pensaert, M. B. (1998a). Porcine reproductive and respiratory syndrome virus infection of alveolar macrophages can be blocked by monoclonal antibodies against cell surface antigens.Advances in Experimental Medicine and Biology 440, 461-467. [Google Scholar]
  10. Duan, X., Nauwynck, H. J., Favoreel, H. W. & Pensaert, M. B. (1998b). Identification of a putative virus receptor for porcine reproductive and respiratory syndrome virus (PRRSV) on porcine alveolar macrophages.Journal of Virology 72, 4520-4523. [Google Scholar]
  11. Hill, H. (1990). Overview and history of mystery swine disease (swine infertility/respiratory syndrome). Proceedings Mystery Swine Disease Committee Meeting, pp. 29–31.
  12. Lee, B. W., Bey, R. F., Baarsch, M. E. & Larson, M. E. (1995). Class specific antibody response to influenza A H1N1 infection in swine.Veterinary Microbiology 43, 241-250.[CrossRef] [Google Scholar]
  13. Mengeling, W. L., Lager, K. M. & Vorwald, A. C. (1995). Diagnosis of porcine reproductive and respiratory syndrome.Journal of Veterinary Diagnostic Investigation 7, 3-16.[CrossRef] [Google Scholar]
  14. Pescovitz, M. D., Lunney, J. K. & Sachs, D. H. (1984). Preparation and characterization of monoclonal antibodies reacting with porcine PBL.Journal of Immunology 133, 368. [Google Scholar]
  15. Plagemann, P. G. W. (1996). Lactate dehydrogenase-elevating virus and related viruses. In Fields Virology, pp. 1105-1120. Edited by B. N. Fields, D. M. Knipe & P. M. Howley. Philadelphia: Lippencott–Raven.
  16. Plagemann, P. G. & Moennig, V. (1992). Lactate dehydrogenase-elevating virus, equine arteritis virus, and simian hemorrhagic fever virus: a new group of positive-strand RNA viruses.Advances in Virus Research 41, 99-192. [Google Scholar]
  17. Rodak, L., Smid, B., Valicek, L. & Jurak, E. (1987). Four-layer enzyme immunoassay (EIA) detection of differences in IgG, IgM and IgA antibody response to Aujeszky’s disease virus in infected and vaccinated pigs.Veterinary Microbiology 13, 121-133.[CrossRef] [Google Scholar]
  18. Rowland, R. R. R., Steffen, M., Ackerman, T. & Benfield, D. A. (1999). The evolution of porcine reproductive and respiratory syndrome virus: quasispecies and emergence of a virus subpopulation during infection of pigs with VR-2332.Virology 259, 262-266.[CrossRef] [Google Scholar]
  19. Sirinarumitr, T., Zhang, Y., Kluge, J. P., Halbur, P. G. & Paul, P. S. (1998). A pneumo-virulent United States isolate of porcine reproductive and respiratory syndrome virus induces apoptosis in bystander cells both in vitro and in vivo.Journal of General Virology 79, 2989-2995. [Google Scholar]
  20. Sur, J.-H., Doster, A. R. & Osorio, F. A. (1998). Apoptosis induced in vivo during acute infection by porcine reproductive and respiratory syndrome virus.Veterinary Pathology 35, 506-514.[CrossRef] [Google Scholar]
  21. Swenson, S. L., Hill, H. T., Zimmerman, J. J., Evans, L. E., Landgraf, J. G., Wills, R. W., Sanderson, T. P., McGinley, M. J., Brevik, A. K., Ciszewski, D. K. & Frey, M. L. (1994). Excretion of porcine reproductive and respiratory syndrome virus in semen after experimentally induced infection in boars.Journal of the American Veterinary Medical Association 204, 1943-1948. [Google Scholar]
  22. Terpstra, C., Wensvoort, G. & Pol, J. M. A. (1991). Experimental reproduction of porcine epidemic abortion and respiratory syndrome (mystery swine disease) by infection with Lelystad virus: Koch’s postulates fulfilled.Veterinary Quarterly 13, 131-136.[CrossRef] [Google Scholar]
  23. Van Reeth, K., Nauwynck, H. J. & Pensaert, M. B. (1996). Dual infections of feeder pigs with porcine reproductive and respiratory syndrome virus followed by porcine respiratory coronavirus or swine influenza virus: a clinical and virological study.Veterinary Microbiology 48, 325-335.[CrossRef] [Google Scholar]
  24. Van Reeth, K., Labarque, G., Nauwynck, H. & Pensaert, M. (1999). Differential production of proinflammatory cytokines in the pig lung during different respiratory virus infections: correlations with pathogenicity.Research in Veterinary Science 67, 47-52.[CrossRef] [Google Scholar]
  25. Van Zaane, D. & Hulst, M. M. (1987). Monoclonal antibodies against porcine immunoglobulin isotypes.Veterinary Immunology and Immunopathology 16, 23-36.[CrossRef] [Google Scholar]
  26. Wensvoort, G., Terpstra, C., Pol, J. M. A., ter Laak, E. A., Bloemraad, M., de Kluyver, E. P., Kragten, C., van Buiten, L., den Besten, A., Wagenaar, F., Broekhuijsen, J. M., Moonen, P. L. J. M., Zetstra, T., de Boer, E. A., Tibben, H. J., de Jong, M. F., van’t Veld, P., Groenland, G. J. R., van Gennep, J. A., Voets, M. T., Verheijden, J. H. M. & Braamskamp, J. (1991). Mystery swine disease in the Netherlands: the isolation of Lelystad virus.Veterinary Quarterly 13, 121-130.[CrossRef] [Google Scholar]
  27. Wills, R. W., Zimmerman, J. J., Yoon, K.-J., Swenson, S. L., McGinley, M. J., Hill, H. T., Platt, K. B., Christopher-Hennings, J. & Nelson, E. A. (1997). Porcine reproductive and respiratory syndrome virus: a persistent infection.Veterinary Microbiology 55, 231-240.[CrossRef] [Google Scholar]

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error