Fig. 2. Circulating VEGF in GCA patients up-regulates microvascular endothelial Jagged1. Circulating VEGF in GCA patients up-regulates microvascular endothelial Jagged1. Plasma samples were collected from patients with GCA and age-matched healthy controls. Patients with RA served as disease controls. All data are means ± SEM. (A and B) EC monolayers (HMVECs and HUVECs) were treated with 10% GCA plasma, RA plasma, and control plasma. After 6 hours, mRNA transcripts for JAG1, DLL1, and DLL4 were quantified by RT-PCR (A). After 24 hours, Jagged1 protein was measured by flow cytometry (B). Representative histograms and mean fluorescence intensities (MFIs) corrected by background subtraction from four to six independent experiments. (C) Plasma VEGF concentrations in healthy controls, RA patients, and GCA patients. Each dot represents one individual. (D) Jagged1 protein expression on HMVECs and HUVECs treated with hVEGF (10 ng/ml) for 24 hours. Results are from three to four experiments. (E) HMVECs were treated with GCA plasma ± VEGF receptor inhibitor axitinib (1 μM). Representative histogram of Jagged1 expression and MFIs are from four experiments. (F) HMVECs were treated with GCA plasma ± anti-VEGF blocking antibody (10 μg/ml) for 6 hours. JAG1 transcripts were measured by RT-PCR. Data are from three experiments. (G and H) Slices of human medium-sized arteries were cultured for 5 days with hVEGF (100 ng/ml) or vehicle (G). Alternatively, the arteries were kept in medium containing 30% plasma from healthy donors or from GCA patients in the absence or presence of anti-VEGF antibody (100 μg/ml) (H). Jagged1 protein was visualized by immunohistochemical staining with anti-Jagged1 antibody. Isotype antibody was used as control for binding specificity. Representative images are from five experiments. Scale bars, 20 μm. Zhenke Wen et al., Sci Transl Med 2017;9:eaal3322 Published by AAAS