Figure 4.

Autoreactive IgG antibodies in plasma of patients with IPAH correlate with BTK levels. (A) Staining pattern of human epithelial cell (Hep)-2 slides incubated with plasma of HCs and patients with IPAH, CTD-PAH and CHD-PAH. As detection antibodies IgG F(ab′)2 fragments were applied. For each group two representative slides are depicted. (B) Quantification of BTK protein expression levels (gMFI values) in total circulating B cells from patients who were Hep2-positive and Hep2-negative and with IPAH. The results are shown as median (IQR), p exact values were obtained following Mann-Whitney U test. Dots represent values in individual patients. BTK, Bruton’s tyrosine kinase; CTD-PAH, connective tissue disease associated pulmonary arterial hypertension; CHD-PAH, congenital heart disease pulmonary arterial hypertension; gMFI, geometric mean fluorescence intensity; HCs, healthy controls; IPAH; idiopathic pulmonary arterial hypertension.