Fig. 5: Thapsigargin increases IFN-γ by altering Zn²⁺ homeostasis.

PBMC were left untreated, stimulated with 50 ng/ml thapsigargin. A 48 h after thapsigargin stimulation the intracellular Zn²⁺ concentration was determined by FluoZin-3. B 3 h after stimulation the mRNA expression of the Zn²⁺ importer and C the Zn²⁺ exporter were analyzed by qPCR and relative expression was determined by \({{\bf{2}}}^{{\boldsymbol{-}}{\boldsymbol{\Delta }}{\boldsymbol{\Delta }}{{\boldsymbol{C}}}_{{\boldsymbol{T}}}}\) method. The expression of some transporter was not detectable (n.d.). D PBMC were preincubated for 15 min in Zn²⁺-adequate (ZA) or Zn²⁺-deficient (ZD) medium and were subsequently stimulated with thapsigargin. After 48 h, IFN-γ was measured in the supernatant by ELISA. Data are presented as mean + SEM with n = 5 (A), n = 4–10 (B), n = 4 (C) and n = 9 (D) experiments. Statistical significance was determined by paired t-test (*p < 0.05; ***p < 0.001) (A–C) or by Friedman test with Dunn’s multiple comparisons test (D). Significantly different results (p < 0.05) have no common identification letter (D).