2011 Annual Report 1a.Objectives (from AD-416) To improve Foot-and-Mouth Disease Virus (FMDV) vaccine potency and duration of immunity, ARS, PIADC and the University of Vermont (UV) will study the cellular immune response to infection and the ability to refine the killed virus vaccine for FMDV or the recombinant empty capsid vaccine. The objective of this agreement is to analyze T cell responses to FMDV infection in swine and cattle. 1b.Approach (from AD-416) ARS, PIADC in cooperation with the University of Copenhagen is developing state of the art technology for analysis of FMDV vaccine performance in cattle. The product of this collaboration, MHC tetramers for tracking T cell responses to vaccination, will be used to analyze genetically defined cattle. The University of Vermont collaborators maintain a genetically homogenous herd of Holstein cattle that make it possible to use the tetramer technology to analyze the response to vaccination with FMDV new vaccines. ARS, PIADC will collaborate with UV faculty to analyze responses to infection of these cattle with FMDV and mastitis. 3.Progress Report 1. Whole blood samples were collected from approximately 70 Holstein cattle. A typing system for the MHC Class II developed by colleagues at Washington State University has been applied to all 70 samples. Four BoLA Class II alleles have been shown to be dominant in the herd and expression covers 90% of the animals in the herd. The first Class II protein protein is being synthesized for expression and analysis of peptide binding and, 2. The analysis of BoLA Class I expression in the research herd shows 2 very common alleles, expressed in 37% and 43% of the animals. Further analysis is continuing as assays, for some of the alleles have not been optimized. While the completion of this data set is pending, we have synthesized one of the common dominant BoLA class I proteins and plan to synthesize the second FY 2012. This collaboration was monitored through email and telephone exchange as well as site visits to ARS, PIADC and the UVM by principal investigators. In addition, UVM scientists were stationed at ARS, PIADC during FY 2011 to work on this collaboration.