Figure 2.

Ability of GCA Treg to inhibit Teff proliferation is altered in GCA and corrected by blockade of IL‐6 pathway with TCZ. (a) Proliferation of Teff (CD4⁺CFSE⁻ cells) stimulated with anti‐CD2, anti‐CD3 and anti‐CD28 microbeads in the presence or not of GCA Treg or control Treg with a Teff/Treg ratio of 2:1. Proliferation index (PI) was calculated with ModFit LT software using CellTrace Violet incorporation. (b) Assessment of the inhibition of Teff proliferation by Treg: control Treg and control Teff (n = 15), GCA Treg and GCA Teff (n = 13), GCA Treg, GCA Teff and TCZ (5 µg mL⁻¹) (n = 8) and control Treg and GCA Teff (n = 4). The percentage of inhibition was also calculated: 100 × (1‐(proliferation index of Teff cultured with Treg/proliferation index of Teff culture without Treg)). The higher this percentage is, the more the Treg are suppressive. Histograms show the mean ± SEM, and P is the result of Student's t‐tests or paired Student's t‐tests, as appropriate. NS, not significant. *P < 0.05 and **P < 0.01.