Proteomic profile of extracellular vesicles in anaphylaxis and their
role in vascular permeability
Abstract
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.