Naïve γδ T cells express TLRs but do not secrete IL-17 in response to TLR stimulation.

<p><b>(A, B)</b> γδ T cells were isolated from C57BL/6J mice and stained at their cell surface (TLR1, TLR2, TLR4) or intracellularly (TLR7, TLR9, MyD88) with antibodies directed against the indicated TLR (solid line) and the respective isotype control (dotted line). Data are displayed as delta (Δ) mean fluorescence intensity (MFI) of the specific antibody in relation to the isotype control ± SEM from 3 to 5 individual experiments. <b>(C, D)</b> γδ T cells were isolated from C57BL/6J mice and stimulated with the TLR ligands Pam3CysSK4 (100 ng/ml), LPS (100 ng/ml), imiquimod (10 μg/ml), CpG (1 μM), or IL-1β and IL-23 (10 ng/ml each). Unstimulated cells served as a negative control. After 3 days, cells were re-stimulated and analyzed by flow cytometry for intracellular IFN-γ and IL-17 expression. Results in <b>(D)</b> are shown as mean ± SEM of 3 experiments, ANOVA with Dunnett´s multiple comparison post test of each ligand <i>vs</i>. unstimulated control. <b>(E)</b> γδ T cells were stimulated as described in <b>(C)</b>, but supernatants were collected directly after 3 days and analyzed by IL-17 ELISA. Results are shown as mean ± SEM of 3 individual experiments, ANOVA with Dunnett´s multiple comparison post test of each ligand <i>vs</i>. unstimulated control, (D) <i>p</i> = 0.3262, <i>p</i> = 0.0355, (E) <i>p</i> = 0.4647.