CD4+ and γδTCR+ T lymphocytes are sources of interleukin-17 in swine.
In the veterinary field, only limited information is available about interleukin-17A (IL-17), despite the fact that this cytokine plays an important role during pro-inflammatory immune responses and induces the production of chemotactic factors for neutrophils. The aim of this study was to characterize porcine IL-17-producing cells. We tested the cross-reactivity of five anti-human IL-17 monoclonal antibodies because such antibodies against porcine IL-17 are currently unavailable. Whole blood cells (WBCs) were stimulated with phorbol-myristate-acetate (PMA) and ionomycin and subsequently analyzed by flow cytometry. The antibody clone SCPL1362 was found to cross-react with porcine IL-17, whereas the other four antibodies tested did not recognize this cytokine. Using this antibody, we characterized porcine WBC-secreting IL-17 after PMA and ionomycin stimulation. All IL-17-producing WBCs were positive for the T lymphocyte marker CD3. Myeloid cells (CD172α(+)) and B lymphocytes (CD79α(+)) were IL-17 negative. The major subset of IL-17 positive T lymphocytes was the CD4(+) lymphocytes (about 60% of all IL-17 positive WBCs). The remaining IL-17 positive WBCs were γδTCR(+) lymphocytes. CD8 positive and CD8 negative cells were found within both CD4(+) and γδTCR(+) cells producing the cytokine. Moreover, IL-17 positive cells were mostly CD45RA negative, therefore activated cells or memory cells. Flow cytometry data were confirmed using sorted cells. Both sorted CD4(+) and γδTCR(+) cells produced IL-17 at mRNA level after PMA and ionomycin stimulation while double negative CD4(-)γδTCR(-) cells were negative for IL-17. We can conclude that only two subpopulations of porcine WBCs are sources of IL-17 after non-specific stimulation: CD3(+)CD4(+) and CD3(+)γδTCR(+).
Veterinary Research Institute, Hudcova 70, 621 00 Brno, Czech Republic.
Hana
H
Stepanova
Marketa
M
Mensikova
Katarina
K
Chlebova
Martin
M
Faldyna
D000818:Animals; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D017931:DNA Primers; D005434:Flow Cytometry; D020381:Interleukin-17 / Q000096:biosynthesis* / Q000235:genetics; D008213:Lymphocyte Activation / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D017931:DNA Primers; D020381:Interleukin-17; D012333:RNA, Messenger; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013755:Tetradecanoylphorbol Acetate