Fig 1: Clinical and immunophenotypic characterization of P1 before and under JAK inhibition. (A) Absolute numbers of leukocytes, monocytes, neutrophils, thrombocytes, eosinophils, CD21low B cells, hemoglobin, and percentage of CD21low B cells in the blood before and under JAK inhibition treatment. Normality was assessed using the Shapiro–Wilk test. For normally distributed data, an unpaired t test was used. For data that were not normally distributed, the Mann–Whitney test was used. *P < 0.05, ***P < 0.0001, ****P < 0.0001. (B) IgE, IgG, IgM, and IgA levels in the blood before and under JAK inhibition treatment. Mann–Whitney test. Normality was assessed using the Shapiro–Wilk test. For normally distributed data, an unpaired t test was used. For data that were not normally distributed, the Mann–Whitney test was used. ns: not significant, *P < 0.05, **P < 0.01. (C) Summary of T cells from P1 expressing TCR αβ (left) or TCR γδ (right) before and under treatment with JAK inhibitor (within 6 mo after start of treatment). Scatter plots of percentages and the median of four independent measurements. Mann–Whitney test. ns: not significant. (D) Summary of percentages of pSTAT5 in TCR αβ (left) or TCR γδ (right) cells isolated from P1 before and under treatment with JAK inhibitor after stimulation with IL-2 (100U/ml) for 4 h. (E) TSNE of TCR Vδ2 cells from P1 before and under treatment with JAK inhibitor distributed in clusters 1–11 according to CD95, CD28, CD26, CD56, KLRG1, NKp80, TIGIT, PD-1, and CD57 expression. (F) Representative flow cytometry plot of TCR Vδ2 vs. TCR γδ on total T cells derived from PBMCs of P1 at different collection dates since the beginning of JAK inhibition treatment. (G) Percentages of TCR γδ, TCR Vδ2, and TCR αβ in PBMCs of P1 at different collection dates since the beginning of JAK inhibition treatment. The data correspond to one experiment. (H) Sanger sequencing of p.Y665F STAT5B region amplified from cDNA of freshly sorted TCR γδ from P1 before treatment (top panel) or under treatment (year of analysis = 2021; bottom panel) with JAK inhibitor.