Syngeneic red blood cell-induced extracellular vesicles suppress delayed-type hypersensitivity to self-antigens in mice

Autor: Philip W. Askenase, Eugenio Bustos-Morán, Noelia Blas-Rus, Bernadeta Nowak, Włodzimierz Ptak, Francisco Sánchez-Madrid, Katarzyna Nazimek, Krzysztof Bryniarski
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Clin Exp Allergy
Popis: Background At present, the role of autologous cells as antigen carriers inducing immune tolerance is appreciated. Accordingly, intravenous administration of haptenated syngeneic mouse red blood cells (sMRBC) leads to hapten-specific suppression of contact hypersensitivity (CHS) in mice, mediated by light chain-coated extracellular vesicles (EVs). Subsequent studies suggested that mice intravenously administered with sMRBC alone may also generate regulatory EVs, revealing the possible self-tolerogenic potential of autologous erythrocytes. Objectives The current study investigated the immune effects induced by mere intravenous administration of a high dose of sMRBC in mice. Methods The self-tolerogenic potential of EVs was determined in a newly developed mouse model of delayed-type hypersensitivity (DTH) to sMRBC. The effects of EV's action on DTH effector cells were evaluated cytometrically. The suppressive activity of EVs, after coating with anti-hapten antibody light chains, was assessed in hapten-induced CHS in wild-type or miRNA-150-/- mice. Results Intravenous administration of sMRBC led to the generation of CD9 + CD81+ EVs that suppressed sMRBC-induced DTH in a miRNA-150-dependent manner. Furthermore, the treatment of DTH effector cells with sMRBC-induced EVs decreased the activation of T cells but enhanced their apoptosis. Finally, EVs coated with antibody light chains inhibited hapten-induced CHS. Conclusions and clinical relevance The current study describes a newly discovered mechanism of self-tolerance induced by the intravenous delivery of a high dose of sMRBC that is mediated by EVs in a miRNA-150-dependent manner. This mechanism implies the concept of naturally occurring immune tolerance, presumably activated by overloading of the organism with altered self-antigens.
Databáze: OpenAIRE