Allergic diseases are allergen-induced immunological disorders characterized by the development of type 2 immunity and IgE responses. The prevalence of allergic diseases has been on the rise alike cardiovascular disease (CVD), which affects arteries of different organs such as the heart, the kidney and the brain. The underlying cause of CVD is often atherosclerosis, a disease distinguished by endothelial dysfunction, fibrofatty material accumulation in the intima of the artery wall, smooth muscle cell proliferation, and Th1 inflammation. The opposed T-cell identity of allergy and atherosclerosis implies an atheroprotective role for Th2 cells by counteracting Th1 responses. Yet, the clinical association between allergic disease and CVD argues against it. Within, we review different phases of allergic pathology, basic immunological mechanisms of atherosclerosis and the clinical association between allergic diseases (particularly asthma, atopic dermatitis, allergic rhinitis and food allergy) and CVD. Then, we discuss atherogenic mechanisms of type 2 immunity and allergic inflammation including acute allergic reactions (IgE, IgG1, mast cells, macrophages and allergic mediators such as vasoactive components, growth factors and those derived from the complement, contact and coagulation systems) and late phase inflammation (Th2 cells, eosinophils, type 2 innate-like lymphoid cells, alarmins, IL-4, IL-5, IL-9, IL-13 and IL-17).

Background: Anaphylaxis is the most severe manifestation of allergic disorders. Diagnostic and understanding of molecular mechanisms need to improve. Extracellular vesicles (EVs) play a key role in cellular communication offering new possibilities to unravel patient-based particularities. The aim of this study is to analyze the protein profile of anaphylaxis-derived EVs providing a resource of potential markers for anaphylactic reactions, and to characterize their molecular mechanisms. Methods: EVs were isolated from 86 plasma samples (collected from 43 patients) during the acute phase of anaphylaxis (AnEVs) and at their baseline (BEVs). For comparison, EVs were characterized and their protein patterns were analyzed by mass spectrometry-based quantitative proteomics (LC-MS/MS). System Biology Analysis (SBA) was applied to identify main canonical pathways and molecules involved. In addition, in vitro permeability assays based on EVs-endothelial cells (ECs) were performed. Results: Differential proteomic analysis performed in 10 EVs paired patients’ samples identified 1206 proteins of which 99 were modulated in the AnEVs signature. CDC42, Ficolin-2 and S100A9 enrichment was confirmed in a larger cohort of patients. SBA revealed diverse group of immune proteins as the main canonical pathways altered in AnEVs. Thus, leukocyte extravasation and granulocyte adhesion-diapedesis processes stand out. In addition, marked-EVs from anaphylactic patients were captured by ECs decreasing the resistance of human endothelial monolayers. Conclusion: Our findings identify for the first time a differential EVs pattern signature in anaphylaxis revealing a source of potential biomarkers. Furthermore, these vesicles could participate in altered immune molecular mechanisms and present a role increasing vascular permeability.

Background and Purpose: Cellular Communication Network Factor 2 (CCN2) is a matricellular protein normally present in the vascular wall but overexpressed in several cardiovascular diseases. CCN2 has been proposed as a downstream mediator of profibrotic actions of Transforming Growth Factor (TGF)-β and Angiotensin II (Ang II). However, its direct role in cardiovascular diseases is not completely understood. Experimental Approach: To investigate the direct role of CCN2 under vascular pathological conditions, a conditionally deficient CCN2 (CCN2-KO) mouse was evaluated infused or not with Ang II. Key Results: In the absence of CCN2, Ang II infusion induced a rapid (within 48 hours) aortic aneurysm generation and increased aneurysm rupture with 80 % lethality at the endpoint. CCN2 deletion caused elastin layer disruption and increased metalloproteinase activity, which were aggravated by Ang II administration. Aortic RNA-seq studies and the subsequent Gene Ontology enriched analysis pointed out the aldosterone biosynthesis process as one of the most enriched terms in absence of CCN2. Pharmacological aldosterone pathway intervention in Ang II-infused CCN2-KO mice, by treatment with the mineralocorticoid receptor antagonist spironolactone, reduced aneurysm formation and mortality after Ang II infusion. Conclusion and Implications: CCN2 deletion induces a rapid aneurysm formation and rupture after Ang II infusion which is partially prevented by blocking the mineralocorticoid receptor. Our present data highlight, for the first time, the potential role of CCN2 as a vascular homeostatic factor and its relevance in the aldosterone synthesis, opening new avenues to future studies in aortic aneurysm treatment.

A document by Emilio Nuñez-Borque. Click on the document to view its contents.