239B Veterinary Science
1971 Commonwealth Avenue
University of Minnesota
St. Paul, MN 55108
The Murtaugh laboratory seeks a comprehensive understanding of porcine immune responses to infectious pathogens, especially porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus 2 (PCV2). PRRSV is a positive-sense, single-stranded RNA virus that infects macrophages without provoking a notable innate response. Nevertheless, adaptive B- and T-cell responses are not significantly delayed. While PRRSV infection is prolonged, the resulting immunity is robust against re-infection with the same virus, and less effective against other strains. The mechanisms of protective immunity are unknown, and means of enhancing primary responses have been difficult to discern. The virus recombines at a high rate to produce chimeric genomes and novel subgenomic RNAs. Understanding the biochemistry and molecular biology of recombination will provide insights into fundamental mechanisms of viral evolution and radiation that may be related to the appearance of novel diseases in swine and other species.
PCV2, a small circular DNA virus, causes a persistent infection. Its small genome, encoding about 3 proteins, is amenable to global dissection and characterization of the complete immune response to a viral pathogen. The results of our research will help the development of novel approaches for treatment of enteric illness and disease, and also will help to identify new pharmacological and immunologic targets capable of enhancing the efficacy of drugs and vaccines.
We are using functional genomic approaches to characterize immunoglobulin diversity in pigs, and to identify specific immunoglobulins expressed in response to infectious challenge. This information will help to elucidate biochemical and molecular mechanisms of immune resistance that can guide future vaccine development.
In previous research, we established an oral immunization model for the induction of mucosal immune responses in swine and have explored the role of cytokines in mediating mucosal adjuvanticity. Cholera toxin is a potent oral adjuvant for both local and distant mucosal, and for systemic responses, and elicits both antibody and cell-mediated immunity. Gene discovery approaches with Salmonella as a model pathogen has been used to identify the complete catalog of molecular responses to intestinal infection. The overall goal of these investigations is to elucidate the initiating molecular and cellular responses in the small intestine that are crucial in determining the outcome of enteric infection and the extent to which they are modified by opioid drugs.
(For a comprehensive list of Dr. Murtaugh's recent publications, refer to PubMed, a service provided by the National Library of Medicine.)
Shi, M., T.T. Lam, C.C. Hon, M.P. Murtaugh, P.R. Davies, R.K. Hui, J. Li, L.T. Wong, C.W. Yip, J.W. Jiang, and F.C. Leung. 2010. Phylogeny-based evolutionary, demographical, and geographical dissection of North American type 2 porcine reproductive and respiratory syndrome viruses. J. Virol. 84:8700-8711.
Puvanendiran S, Stone S, Yu W, Johnson CR, Abrahante J, Garcia Jimenez L, Griggs T, Haley C, Wagner B, Murtaugh MP. 2011. High prevalence of porcine circovirus type 2 exposure and infection in swine finisher herds. Virus Res. 157:92-98. PMID:21352865
Abrahante JE, Martins K, Papas KK, Hering VJ, Schuurman H-J, Murtaugh MP. 2011. Microbiological safety of porcine islets: comparison with source pig. Xenotransplantation. 18:88-93.
Johnson CR, Griggs TF, Gnanandarajah J, Murtaugh MP. 2011. Novel structural protein in Porcine reproductive and respiratory syndrome virus encoded in an alternative open reading frame 5 present in all arteriviruses. J Gen Virol 92:1107-1116. PMID: 21307222
Haley C, Wagner B, Puvanendiran S, Abrahante J, Murtaugh MP. 2011. Diagnostic performance measures of ELISA and quantitative PCR tests for porcine circovirus type 2 exposure using Bayesian latent class analysis. Prev Vet Med. 101:79-88. PMID: 21632130
Schwartz JC, Lefranc M-P, Murtaugh MP. 2011. Evolution of the porcine (Sus scrofa domestica) Immunoglobulin kappa locus through germline gene conversion. Immunogenetics. DOI 10.1007/s00251-011-0589-6. Online, November 23, 2011.
Gnanandarajah JS, Abrahante JE, Lulich JP, Murtaugh MP. 2011. Presence of Oxalobacter formigenes in the intestinal tract is associated with the absence of calcium oxalate urolith formation in dogs. Urol. Res. DOI 10.1007/s00240-011-0451-1. Online, January 6, 2012.
Murtaugh MP, Genzow M. 2011. Immunological solutions for treatment and prevention of porcine reproductive and respiratory syndrome (PRRS). Vaccine. 29:8192-8204.
Schwartz JC, Lefranc M-P, Murtaugh MP. 2011. Organization, complexity and allelic diversity of the porcine (Sus scrofa domestica) immunoglobulin lambda locus. Immunogenetics. DOI 10.1007/s00251-011-0589-6. Online, December 21, 2011.
Murtaugh, M.P. and C.R. Johnson. 2009. Identifying virally infected and vaccinated organisms. United States Patent 7,611,717.
"Diagnostics to differentiate vaccine and filed virus responses in PRRS elimination projects," Boehringer Ingelheim Advanced PRRS Research Award.
"Porcine islet xenotransplantation," Schulze Diabetes Institute.
“Dissemination of PCV2 vial particles from sows to piglets,” Natl Pork Board.
Honors and Awards
University of Minnesota CVM Mark of Excellence, 1996, 2004, 2008.
University of Minnesota Inventor Recognition Award, 2005.
University of Minnesota Innovations Award, 2011.
Sally Robinson, PhD student, Comparative and Molecular Biosciences
John Schwartz, PhD student, Comparative and Molecular Biosciences
Xiong Wang, PhD student, Comparative and Molecular Biosciences