A New Approach for Managing Bovine Tuberculosis: Veterinary Services’ Proposed Action Plan

Bovine tuberculosis (TB) is a serious disease with animal health, public health, and international trade consequences. The cooperative Federal-State-industry effort to eradicate bovine TB from cattle in the United States has made significant progress since the program’s inception in 1917. However, the goal of eradication remains elusive. This proposed action plan presents Veterinary Services’ (VS’) current thinking about changes we are considering for the TB program to address our current challenges. This action plan will: 1. Reduce the introduction of TB into the U.S. national herd from imported animals and wildlife by: o Applying additional requirements to cattle imports from Mexico o Enhancing efforts to mitigate risks from wildlife 2. Enhance TB surveillance by: o Crafting a comprehensive national surveillance plan o Accelerating diagnostic test development to support surveillance 3. Increase options for managing TB-affected herds by: o Conducting epidemiological investigations and assessing individual herd risk o Applying whole-herd depopulation judiciously and developing alternative control strategies o Applying animal identification (ID) standards to meet animal ID needs 4. Modernize the regulatory framework to allow VS to focus resources where the disease exists 5. Transition the TB program from a State classification system to a science-based zoning approach to address disease risk To succeed, this new approach will require VS’ continued partnership with State animal health and wildlife officials, other Federal agencies, industry, international partners, academia, and other stakeholders. Successful partnerships will allow us to use available resources efficiently to achieve program objectives and protect our nation’s herd. Implementation of the VS proposed action plan will benefit Federal and State animal health officials, the regulated industries, and producers by allowing a more rapid response that employs up-to-date science and can adapt rapidly to changing situations.

THE GLYCOPROTEINS OF PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS AND THEIR ROLE IN INFECTION AND IMMUNITY

The porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important pathogen of swine and is known to cause abortion and infertility in pregnant sows and respiratory distress in piglets. PRRSV contains a major glycoprotein (GP5) and three minor glycoproteins (GP2a, GP3, and GP4) on the virion envelope, all of which are required for infectious virus production. To study their interactions amongst each other and with a cellular receptor for PRRSV, CD163, I cloned each of the viral glycoproteins and CD163 in various expression vectors. My studies have shown that while the GP2a, GP3, and GP4 are co-translationally glycosylated, the GP5 is post-translationally glycosylated. By using co-immunoprecipitation (co-IP) assays, strong interaction was demonstrated between GP4 and GP5 proteins, although weak interactions among the other envelope glycoproteins were also detected. Further, GP4 was found to mediate interactions leading to formation of multiprotein glycoprotein complex. My results also show that GP2a and GP4 proteins are the only two GPs that specifically interact with the CD163 molecule and that glycosylation of these GPs is required for efficient interaction. Based on these studies, I have developed an interactome map of the viral GPs and CD163 and have proposed a model of the viral glycoprotein complex and its interaction with CD163. Studies reported here also show that glycan addition at residue 184 (N184) of GP2a, and residues N42, N50, and N131 of GP3 is essential for recovery of infectious virus. Although single site glycosylation mutants of GP4 had no effect on infectious virus production, introduction of double mutations was lethal. The loss of glycan moieties of GP2a, GP3, and GP4 proteins had no effect on host neutralizing antibody production. Overall, I conclude that the PRRSV glycoproteins are co-translationally and post-translationally glycosylated, the GP4 protein is central to mediating interglycoprotein interactions, and along with GP2a, serves as the viral attachment protein that is responsible for interactions with the viral receptor, CD163. Further, glycosylation of GP2a, GP3, and GP4 proteins is required for infectious virus production, efficient interaction with CD163, but does not play any role in neutralizing antibody response in infected animals.

Fourth Annual Symposium in Virology

What a pleasure it is to take part in welcoming you to this Fourth Annual Symposium in Virology. Such a tremendous program lies ahead! And how pleased and proud we are that this year's symposium is a special tribute to our colleague Dr. James Van Etten, Professor of Plant Pathology in our Institute of Agriculture and Natural Resources here at the University of Nebraska-Lincoln, who last-year was elected to membership in the National Academy of Sciences.

Department of Veterinary and Biomedical Sciences: 2000 Annual Report

Foreword, 2000 John A . Schmitz. Professor and Department Head Veterinary and Biomedical Sciences Personnel Faculty Profiles Teaching program Research program Extension Program Nebraska Veterinary and Diagnostic Laboratory Systems Grants and Contracts Funded or Active in 2000 Patents by VBMS Faculty in 2000 Publications by VBMS Faculty in 2000 Presentations by VBMS Faculty in 2000 Articles Regarding the Department in 2000 Selected Committees, Editorial and Other Appointments of VBMS Faculty Departmental Budget Summaries Nebraska Agricultural Statistics 1999

Department of Veterinary and Biomedical Sciences 2004 Annual Report

Veterinary and Biomedical Sciences Personnel VBMS Teaching Program VBMS Research Program International Activities, 2004 Veterinary Extension Program. 2004 VBMS Grants and Contracts Program. 2004 Refereed Publications by VBMS Faculty in 2004 Department of Veterinary and Biomedical Sciences. Selected Committees, Editorial and Other Appointments. 2004 Articles Regarding the Department in 2004 Departmental Budget Summaries. 2004 Nebraska Agricultural Statistics. 2003/2004