Neutrophil migration and ROS activation induced by anti-AT1R and anti-ETAR Ab-positive SSc-IgG. Supernatants of HMEC-1 conditioned with anti-AT1R and anti-ETAR Ab-positive SSc-IgG induce activation and recruitment of neutrophils, measured by transendothelial migration and ROS generation. (A) Significantly increased transendothelial neutrophil migration with SSc-IgG-conditioned supernatants compared with NC-IgG and decrease in samples with receptor antagonism, as indicated (NC-IgG, n = 5, SSc-IgG, n = 7, P < 0.05). (B) Neutrophil migration is induced by IL-8 in supernatants shown by IL-8 neutralization (anti-IL-8 Ab) and NF-κB inactivation (TPCK) (SSc-IgG n = 7, P < 0.05). (C) Increased ROS activation in neutrophils treated with SSc-IgG conditioned HMEC-1 supernatants compared with NC-IgG or untreated (NC-IgG, n = 8, SSc-IgG, n = 12, P < 0.05; P < 0.01). Mean and SEM. **P < 0.01 and *P < 0.05. (D) Neutrophil migration shows a positive correlation to anti-AT1R Abs and anti-ETAR Abs in the IgG samples used (NC-IgG, n = 5; SSc-IgG, n = 7; total, n =12). Spearman correlation.
Kill et al. Arthritis Research & Therapy 2014 16:R29 doi:10.1186/ar4457