Subcutaneous injection of exosomes reduces symptom severity and mortality induced by Echinostoma caproni infection in BALB/c mice

Trelis M¹, Galiano A², Bolado A², Toledo R², Marcilla A¹, Bernal D³.

Int J Parasitol. 2016 Nov;46(12):799-808

Speaker: Chia-Yun Tsai (蔡佳芸)                                 Time: 13:00~14:00, May.31, 2017

Commentator: Dr. Chih-Li Hsu (胥直利老師)            Place: Room 601

Abstract:

Exosomes have been described as an important part of the excretory/secretory pathway in mediating host-parasite communication¹. These parasite-derived extracellular vesicles transport specific information as well as infectious agent which can alter immune responses². In this study, the authors demonstrated a model of intestinal helminth infection in which Echinostoma caproni secreted exosomes deliver effector cargo to modulate the immune system in BALB/c mice. To determine the immunomodulatory role of exosomes, BALB/c mice were administered with purifiedEchinostoma caproni exosomes for further evaluation. The results illustrated that administration of exosomes in BALB/c mice increased the survival rate and reduced the symptom severity upon infection. Immunizations with exosomes induced humoral antibody responses with elevated levels of IgG1, IgG2b, IgG3 and IgM, generated against exosomal proteins. These antibodies recognized specific exosomal proteins, suggesting that exosomes transmit particular antigen to host cell involved in immune responses. Furthermore, expression of IL-4 and TGF-β cytokines with a blunt overproduction of IL10 after immunizations with exosomes represented a Th2/Treg phenotype. To be brief, the potential applications of parasite-derived exosomes modulating the immune system herein may offer a novel therapeutic strategy for parasitic infections.

References:

1.    Marcilla A, Martin-Jaular L, Trelis M, de Menezes-Neto A, Osuna A, Bernal D, et al. Extracellular vesicles in parasitic diseases. Journal of extracellular vesicles 2014, 3: 25040.

2.    Coakley G, Maizels RM, Buck AH. Exosomes and Other Extracellular Vesicles: The New Communicators in Parasite Infections. Trends in parasitology 2015, 31(10): 477-489.