Background— Previous studies suggested that blockade of RAGE in diabetic apolipoprotein (apo) E–null mice suppressed early acceleration of atherosclerosis. A critical test of the potential applicability of RAGE blockade to clinical settings was its ability to impact established vascular disease. In this study, we tested the hypothesis that RAGE contributed to lesion progression in established atherosclerosis in diabetic apoE-null mice. Methods and Results— Male apoE-null mice, age 6 weeks, were rendered diabetic with streptozotocin or treated with citrate buffer. At age 14 weeks, certain mice were killed or treated with once-daily murine soluble RAGE or albumin; all mice were killed at age 20 weeks. Compared with diabetic mice at age 14 weeks, albumin-treated animals displayed increased atherosclerotic lesion area and complexity. In diabetic mice treated with sRAGE from age 14 to 20 weeks, lesion area and complexity were significantly reduced and not statistically different from those observed in diabetic mice at age 14 weeks. In parallel, decreased parameters of inflammation and mononuclear phagocyte and smooth muscle cell activation were observed. Conclusions— RAGE contributes not only to accelerated lesion formation in diabetic apoE-null mice but also to lesion progression. Blockade of RAGE may be a novel strategy to stabilize atherosclerosis and vascular inflammation in established diabetes.

The receptor for advanced glycation end products (RAGE) and its proinflammatory S100/calgranulin ligands are enriched in joints of subjects with rheumatoid arthritis (RA) and amplify the immune/inflammatory response. In a model of inflammatory arthritis, blockade of RAGE in mice immunized and challenged with bovine type II collagen suppressed clinical and histologic evidence of arthritis, in parallel with diminished levels of TNF-alpha, IL-6, and matrix metalloproteinases (MMP) 3, 9 and 13 in affected tissues. Allelic variation within key domains of RAGE may influence these proinflammatory mechanisms, thereby predisposing individuals to heightened inflammatory responses. A polymorphism of the RAGE gene within the ligand-binding domain of the receptor has been identified, consisting of a glycine to serine change at position 82. Cells bearing the RAGE 82S allele displayed enhanced binding and cytokine/MMP generation following ligation by a prototypic S100/calgranulin compared with cells expressing the RAGE 82G allele. In human subjects, a case-control study demonstrated an increased prevalence of the 82S allele in patients with RA compared with control subjects. These data suggest that RAGE 82S upregulates the inflammatory response upon engagement of S100/calgranulins, and, thereby, may contribute to enhanced proinflammatory mechanisms in immune/inflammatory diseases.

A retrospective database was developed by the European Society of Thoracic Surgeons, collecting patients submitted to surgery for thymic tumours to analyse clinico-pathological prognostic predictors. A total of 2151 incident cases from 35 institutions were collected from 1990 to 2010. Clinical-pathological characteristics were analysed, including age, gender, associated myasthenia gravis stage (Masaoka), World Health Organization histology, type of thymic tumour [thymoma, thymic carcinoma (TC), neuroendocrine thymic tumour (NETT)], type of resection (complete/incomplete), tumour size, adjuvant therapy and recurrence. Primary outcome was overall survival (OS); secondary outcomes were the proportion of incomplete resections, disease-free survival and the cumulative incidence of recurrence (CIR). A total of 2030 patients were analysed for OS (1798 thymomas, 191 TCs and 41 NETTs). Ten-year OS was 0.73 (95% confidence interval 0.69–0.75). Complete resection (R0) was achieved in 88% of the patients. Ten-year CIR was 0.12 (0.10–0.15). Predictors of shorter OS were increased age (P < 0–001), stage [III vs I HR 2.66, 1.80–3.92; IV vs I hazard ratio (HR) 4.41, 2.67–7.26], TC (HR 2.39, 1.68–3.40) and NETT (HR 2.59, 1.35–4.99) vs thymomas and incomplete resection (HR 1.74, 1.18–2.57). Risk of recurrence increased with tumour size (P = 0.003), stage (III vs I HR 5.67, 2.80–11.45; IV vs I HR 13.08, 5.70–30.03) and NETT (HR 7.18, 3.48–14.82). Analysis using a propensity score indicates that the administration of adjuvant therapy was beneficial in increasing OS (HR 0.69, 0.49–0.97) in R0 resections. Masaoka stages III–IV, incomplete resection and non-thymoma histology showed a significant impact in increasing recurrence and in worsening survival. The administration of adjuvant therapy after complete resection is associated with improved survival.

Acute pulmonary embolism generally resolves within 6 months. However, if the thrombus is infected, venous thrombi transform into fibrotic vascular obstructions leading to chronic deep vein thrombosis and/or chronic thromboembolic pulmonary hypertension (CTEPH), but precise mechanisms remain unclear. Neutrophils are crucial in sequestering pathogens; therefore, we investigated the role of neutrophil extracellular traps (NETs) in chronic thrombosis. Because chronic pulmonary thrombotic obstructions are biologically identical to chronic deep venous thrombi, the murine inferior vena cava ligation model was used to study the transformation of acute to chronic thrombus. Mice with staphylococcal infection presented with larger thrombi containing more neutrophils and NETs but less resolution. Targeting NETs with DNase1 diminished fibrosis and promoted thrombus resolution. For translational studies in humans, we focused on patients with CTEPH, a severe type of deep venous and pulmonary artery fibrotic obstruction after thrombosis. Neutrophils, markers of neutrophil activation, and NET formation were increased in CTEPH patients. NETs promoted the differentiation of monocytes to activated fibroblasts with the same cellular phenotype as fibroblasts from CTEPH vascular occlusions. RNA sequencing of fibroblasts isolated from thrombo-endarterectomy specimens and pulmonary artery biopsies revealed transforming growth factor-β (TGF-β) as the central regulator, a phenotype which was replicated in mice with fibroblast-specific TGF-β overactivity. Our findings uncover a role of neutrophil-mediated inflammation to enhance TGF-β signaling, which leads to fibrotic thrombus remodeling. Targeting thrombus NETs with DNases may serve as a new therapeutic concept to treat thrombosis and prevent its sequelae.