Figure 9
Curcumin, but not carnosol, significantly inhibits T cell immune responses in ex-vivo stimulated PBMC from psoriasis patients. PBMC isolated from psoriasis patients (n = 9) were treated with carnosol (5 µM), curcumin (5 µM) or a vehicle control for 6 hours prior to stimulation with anti-CD3. After 4 days, supernatants were removed for analysis of IFNγ and IL-17 concentration by ELISA, and proliferation and cytokine production by T cells was analysed by flow cytometry. CD3+CD8- T cell populations were gated according to the strategy shown in Supplemental Fig. 11. (A) Pooled data depicting mean (±SEM) percentage expression of the proliferation marker Ki67 in CD3+CD8- T cells from control, carnosol or curcumin treated PBMC. (B) Pooled data depicting mean (±SEM) CD3+TCRγδ+ cells as a percentage of total live cells from control, carnosol or curcumin treated PBMC. (C) Pooled data depicting mean (±SEM) percentages of TNFα, IL-2, IFNγ, IL-17A, GM-CSF and IL-22 positive CD3+CD8− T cells from control, carnosol or curcumin treated PBMC. (D) Pooled data depicting mean (±SEM) concentrations of IFNγ and IL-17 in cell culture supernatants of control, carnosol and curcumin treated PBMC (means of three technical replicates per patient). (E) PBMC from a healthy human donor were treated with carnosol (1–5 µM), curcumin (1–5 µM), or a vehicle control for 24 hours. Expression of HO-1 was measured by western blot. The blots shown are derived from the same gel; membranes were first probed for HO-1 and then re-probed for β-actin. Full length blots are presented in Supplemental Fig. 9. (F) The cytokine expression profiles of T cells from control, carnosol and curcumin treated psoriasis PBMC were analysed using SPICE software. The pie charts represent the average frequencies of CD3+CD8- T cells producing every combination of cytokines for multiple patients (n = 9). The segments within the pie charts denote proportions of the CD3+CD8− T cell population producing different combinations of cytokines, and are heat-map coded to indicate increasing cytokine production. The arcs surrounding the pie charts indicate the cytokine(s) produced by that proportion of cells. Statistical significance was determined by one-way ANOVA with Dunnett’s post hoc test to compare carnosol and curcumin treatment to the control (**p < 0.01, *p < 0.05).
