Figure 5.

Increased proportions of cTfh-17 cells in patients with IPAH. (A) Representative gating strategy for the identification of CXCR5⁺ cTfh cells, starting from non-regulatory (CD25⁺CD127^low) CD4⁺CD45RA⁻ memory T cells, and further discrimination of cTfh subsets based on surface CCR6 and CXCR3 expression: cTfh-1 (CCR6⁻CXCR3⁺), cTfh17.1 (CCR6⁺CXCR3⁺), cTfh17 (CCR6⁺CXCR3⁻) and cTfh2 (CCR6⁻CXCR3⁻), as depicted for a HC and patient with IPAH. (B) Proportions of CXCR5⁺ memory T cells as percentages of total memory CD4⁺ T cells. (C) Proportions of the indicated cTfh subsets as percentages of CXCR5⁺ memory CD4⁺ T cells. (D) Correlations of cTfh subsets and BTK protein in total B cells. The results are shown as median (IQR), p exact values were obtained following Mann-Whitney U test. Correlation coefficient was calculated using Spearman’s rank method. Dots represent values in individual patients. BTK, Bruton’s tyrosine kinase; cTfh, circulating follicular T helper; IPAH, idiopathic pulmonary arterial hypertension.