Leishmania mexicana: Novel Insights of Immune Modulation through Amastigote Exosomes.

Leishmania mexicana: Novel Insights of Immune Modulation through Amastigote Exosomes. J Immunol Res. 2020;2020:8894549 Authors: Soto-Serna LE, Diupotex M, Zamora-Chimal J, Ruiz-Remigio A, Delgado-Domínguez J, Cervantes-Sarabia RB, Méndez-Bernal A, Escalona-Montaño AR, Aguirre-García MM, Becker I Abstract Exosomes are extracellular microvesicles of endosomal origin (multivesicular bodies, MVBs) constitutively released by eukaryotic cells by fusion of MVBs to the plasma membrane. The exosomes from Leishmania parasites contain an array of parasite molecules such as virulence factors and survival messengers, capable of modulating the host immune response and thereby favoring the infection of the host. We here show that exosomes of L. mexicana amastigotes (aExo) contain the virulence proteins gp63 and PP2C. The incubation of aExo with bone marrow-derived macrophages (BMMs) infected with L. mexicana led to their internalization and were found to colocalize with the cellular tetraspanin CD63. Furthermore, aExo inhibited nitric oxide production of infected BMMs, permitting enhanced intracellular parasite survival. Expressions of antigen-presenting (major histocompatibility complex class I, MHC-I, and CD1d) and costimulatory (CD86 and PD-L1) molecules were modulated in a dose-dependent fashion. Whereas MHC-I, CD86 and PD-L1 expressions were diminished by exosomes, CD1d was enhanced. We conclude that aExo of L. mexicana are capable of decr...
Source: Journal of Immunology Research - Category: Allergy & Immunology Tags: J Immunol Res Source Type: research