Long-Term In Vitro Passaging Had a Negligible Effect on Extracellular Vesicles Released by Leishmania amazonensis and Induced Protective Immune Response in BALB/c Mice

Figure 3

Immunization with EVs released by promastigotes of the reference strain of L. amazonensis incubated at 26 or 37°C. BALB/c mice were handled with the 2 doses protocol of EVs from L. amazonensis reference strain. (a) The lesion size (millimeter (mm)) measurements. Each point represents the average of the individual measurement (). ANOVA followed by a post hoc Tukey’s test was performed . Nonimmunized mice compared with mice immunized with EVs obtained at 26°C. (b) Parasite load (). Bars denote the average of 5 measurements, and error bars denote the SD. ANOVA followed by a post hoc Tukey’s test. (c) Production of IgG1 and IgG2a isotype antibody anti-EVs after two doses of EV immunizations. (d) Measurement of the IgG1 and IgG2a isotype antitotal extract of L. amazonensis in mice immunized and infected with the parasite. Bars represent the average of 5 measurements, and error bars show the SD. Two-way ANOVA followed by a post hoc Sidak test . EVs −26°C—mice immunized twice with EVs obtained from L. amazonensis promastigotes incubated for 4 h at 26°C; EVs −37°C—mice immunized with 2 doses of EVs obtained from L. amazonensis promastigotes incubated for 4 h at 37°C. Data are representative of 3 independent experiments.

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