Exposure to T. cruzi trypomastigotes or purified trans-sialidase is sufficient to trigger B cell IL-17 production
(a,d–g) IL-17A secretion by B220+CD19+ cells or (b–c) IL-17A and IL-17F production by follicular (FM), marginal zone (MZ) and transitional 1 (T1) B cell subsets purified from spleens of UI WT mice and stimulated for 72 h with: (a) various doses of live T. cruzi trypomastigotes (Tryp) or T. cruzi antigen (Ag); or (b–g) 1 × 106 Tryp or different doses of active vs. inactive trans-sialidase (Tsial) with or without a Tsial-neutralizing mAb (α-Tsial) or IgG2a isotype control. (f) B220+CD19+ cells from UI WT mice were cultured with Tryp, Tsial or different doses of bacterial V. cholerae and C. perfringens neuramidases (NA). (g) B220+CD19+ cells from WT mice were cultured with Tryp or Tsial for 72 h in medium containing FBS or 2% BSA with alpha(2,3)-sialyllactose (α-2,3-SL) and alpha(2,6)-sialyllactose (α-2,6-SL) or in identical media lacking acceptor lactose. All error bars denote s.e.m. *, P ≤ 0.05 **, P ≤ 0.005 (calculated by Mann-Whitney U-test). Results are representative of 3 independent experiments with 2 replicates per condition. ND: None detectable.