Supplementary Figure 1.

Functional validation of novel mutations. (A): RT-PCR of STAT3-target SOCS3 at baseline and in IL-21 activated-EBV cell lines of P3 and P4. Results are shown as relative expression normalized to RPLPO housekeeping gene and represent the mean of 6 independent experiments. ∗P < .05, ∗∗P < .01, ∗∗∗P < ,005 Mann-Whitney test; HC: results pooled from 2 healthy controls (HC1 in green, HC2 in blue), PC: positive control; (B): Decreased CTLA-4 mean fluorescence intensity (MFI) on circulating T-cells in P1, P7 and P20 as compared to healthy control (HC) by flow cytometry; (C): B-cell immunophenotyping in P8, showing decreased frequency of CD27+ and excess of CD21^lowCD38^low B-cells.