Extracellular Vesicles Released by Leishmania (Leishmania) amazonensis Promastigotes with Distinct Virulence Profile Differently Modulate the Macrophage Functions

• Published in: Microorganisms (Basel) 2023-12, Vol.11 (12), p.2973
• Main Authors: Zauli, Rogéria Cristina, de Souza Perez, Isabelle Carlos, de Morais, Aline Correia Costa, Ciaccio, Ana Carolina, Vidal, Andrey Sladkevicius, Soares, Rodrigo Pedro, Torrecilhas, Ana Claudia, Batista, Wagner Luiz, Xander, Patricia
• Format: Article
• Language: English
• Subjects: Cell activation; Developing countries; Extracellular vesicles; Gene expression; Glycoproteins; Immune response; Immune system; Immunomodulation; Immunosuppressive agents; Infections; Inflammation; LDCs; Leishmania; Leishmania (Leishmania) amazonensis; Leishmaniasis; Macrophages; Parasites; Parasitic diseases; Polymerase chain reaction; Promastigotes; Proteins; Protozoa; Synergistic effect; Vector-borne diseases; Vesicles; Virulence; Virulence factors
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms11122973

spp. is the aetiologic agent of leishmaniasis, a disease endemic in several developing countries. The parasite expresses and secretes several virulence factors that subvert the macrophage function and immune response. Extracellular vesicles (EVs) can carry molecules of the parasites that show immunomodulatory effects on macrophage activation and disease progression. In the present work, we detected a significantly higher expression of lpg3 and gp63 genes in promastigotes recovered after successive experimental infections (IVD-P) compared to those cultured for a long period (LT-P). In addition, we observed a significantly higher percentage of infection and internalized parasites in groups of macrophages infected with IVD-P. Macrophages previously treated with EVs from LT-P showed higher percentages of infection and production of inflammatory cytokines after the parasite challenge compared to the untreated ones. However, macrophages infected with parasites and treated with EVs did not reduce the parasite load. In addition, no synergistic effects were observed in the infected macrophages treated with EVs and reference drugs. In conclusion, parasites cultured for a long period in vitro and recovered from animals' infections, differently affected the macrophage response. Furthermore, EVs produced by these parasites affected the macrophage response in the early infection of these cells.