Pathogen-reactive T helper cell analysis in the pig
Autor/innen
- F. Ebner
- P. Schwiertz
- S. Steinfelder
- R. Pieper
- J. Zentek
- N. Schütze
- C.G. Baums
- G. Alber
- P. Geldhof
- S. Hartmann
Journal
- Frontiers in Immunology
Quellenangabe
- Front Immunol 8: 565
Zusammenfassung
There is growing interest in studying host–pathogen interactions in human-relevant large animal models such as the pig. Despite the progress in developing immunological reagents for porcine T cell research, there is an urgent need to directly assess pathogen-specific T cells—an extremely rare population of cells, but of upmost importance in orchestrating the host immune response to a given pathogen. Here, we established that the activation marker CD154 (CD40L), known from human and mouse studies, identifies also porcine antigen-reactive CD4(+) T lymphocytes. CD154 expression was upregulated early after antigen encounter and CD4(+)CD154(+) antigen-reactive T cells coexpressed cytokines. Antigen-induced expansion and autologous restimulation enabled a time- and dose-resolved analysis of CD154 regulation and a significantly increased resolution in phenotypic profiling of antigen-responsive cells. CD154 expression identified T cells responding to staphylococcal Enterotoxin B superantigen stimulation as well as T cells responding to the fungus Candida albicans and T cells specific for a highly prevalent intestinal parasite, the nematode Ascaris suum during acute and trickle infection. Antigen-reactive T cells were further detected after immunization of pigs with a single recombinant bacterial antigen of Streptococcus suis only. Thus, our study offers new ways to study antigen-specific T lymphocytes in the pig and their contribution to host–pathogen interactions.