Defining the T cell antigen proteome of wasp venom

Background While modulation of T cell function is believed to be important in the successful acquisition of clinical tolerance during venom immunotherapy, little is known of the role of wasp venom specific T cell antigens. Objective We sought comprehensively to characterize the T cell proteome for wasp venom to facilitate the future development of T cell-based immunotherapeutic approaches. Methods Using peripheral blood mononuclear cells from wasp venom-allergic individuals and IL-4 ELISPOT analysis, we characterized T cell responses to whole venom and gel filtration/ion exchange-fractionated venom. Reactive fractions were purified and identified using highly sensitive electrospray ion-trap mass spectrometry. Results Wasp venom-allergic individuals have detectable whole wasp venom-specific T cells directly ex vivo, which show rapid IL-4 effector function. T cell responses to gel filtration/ion exchange fractionated venom were dominated by responses to phospholipase A(1), hyaluronidase and antigen 5. Conclusion Although it is likely that there are many T cell antigens within wasp venom, the main responses are to proteins coincident with the known IgE-binding proteins.