2012 Annual Report
The objectives of this project are 1: To determine methods of activation of NK cells in response to FMDV infection. 2: To design soluble gamma-delta T cell receptor (sTCR) of bovine and to investigate the viral antigen binding capability of gamma-delta T cells . Antigens identified through the sTCR will be studied regarding their capacity to stimulate gamma-delta T cells.
During FY 2012, we tested various biophospho-antigens for their capability to stimulate bovine gammadelta T cells as has been reported in human and mouse studies. The purpose of experiments is to find suitable biophospho-antigens that are able to stimulate bovine gammadelta T cells and can be optimized for use in enhancing innate immunity in the bovine. These antigens were shown to activate gammadelta T cells to increase the expression of cytokines with only a marginal degree of proliferation.
Over the life of the project we expect to derive soluble T cell receptors (sTCR) of gamma/delta T cells. These soluble receptors will allow us to show whether the gamma/delta T cells are involved in FMDV antigen recognition and if so what antigens these are and if they could be used in targeting FMDV. Since we have observed a moderate increase in activation following culture of gammadelta T cells in the presence of biophospho-antigens, in FY 2013 we plan to follow up this result by performing cytotoxicity assays. Once we have solved the problems with establishment of highly purified gamma/delta T cells for cloning, we will diversity of the TCR gamma/delta TCR in the clones raised previously. This will enable us to single out the dominating gamma/delta T cells which will form the basis of soluble TCR construction.
Impact: This work will help determine if the early, innate gamma/delta T cell responses to FMDV infection in cattle are mediated by an antigen nonspecific reactivity where the TCR is acting as a pathogen recognition receptor (PRR) or if there is antigen specificity involved in this T cell activation.
Technology transfers include; Indicator cells (K562-pmaxFP) have been developed and can be transferred to other users for analysis of T cell activation.
Publications for the reporting period include;
1. Toka FN and WT Golde. Cell mediated innate responses of cattle and swine during virus infection: A unique landscape of innate immunity. Manuscript submitted to Veterinary Immunology & Immunopathology.
2. R. Waters, P. Dar, J. Patch, M. Kenney, R. Glabman, F. Toka, and W. Golde. Analysis of bovine natural killer (NK) cell and ¿d T cell mediated cytotoxicity following infection with foot-and-mouth disease virus (FMDV). Abstract - Submitted to the European Veterinary Immunology Workshop, Edinburgh, 2-4 September 2012.