In contrast, the amount of CD8+ T cells that migrated to the ear of the SGE-3X group was 70% higher than the SGE-1X group (Figure 2B). Regarding to dendritic cells,
there was no difference among all groups analyzed (Figure 2D). Therefore, pre-exposure of saliva leads to changes in the pattern of leukocyte learn more migration to the site of inoculation. selleck Figure 2 Comparative analyses of the inflammatory infiltrate into the site of infection after SGE inoculation. BALB/c mice were inoculated i.d. once (SGE-1X-gray bars) or three times (SGE-3X–black bars) within the ear dermis with SGE (derived from 0.5 pair of salivary glands diluted in 10 μl of PBS/ear) or PBS (10 μl/ear-white bars). The mice were euthanized 24 h later, and ears were harvested for inflammatory infiltrate characterization. The total number of CD4+ T cells (A), CD8+ T cells (B), CD4+CD25+ cells (C); dendritic cells (D), macrophages (E) and neutrophils (F) present within the ears were identified by flow cytometry. Data represent the mean ± SEM and are representative of three independent experiments (n = 4). # P < 0.05 compared with PBS (control check details group). *P < 0.05 compared with the SGE-1X group. The effect of different SGE doses on the course
of L. braziliensis infection Next, we evaluated whether pre-exposure to saliva interferes with the course of L. braziliensis infections. To this end, 1 × 105 L. braziliensis stationary phase promastigote forms suspended in PBS or SGE were inoculated into BALB/c mice ear pretreated with PBS-2X or SGE-2X. The development Immune system of the lesion was monitored weekly by measuring the diameter of the infected ear with a vernier caliper and comparing it with the non-infected ear on the same mouse. Mice challenged with the parasite in the presence of SGE-1X or PBS showed an increased in the lesion beginning on the 3rd week and continued to progress until the 5th week of infection (p < 0.05) (Figure 3A). After the 5th week, we observed a decrease in the ear size until the 7th week. Despite similar rates of edema in both
groups (SGE-1X and PBS), mice that received SGE-1X showed higher parasite titers in the ear at the 3rd and 7th week post-infection when compared with mice inoculated with parasites in PBS (Figure 3B). Conversely, mice pretreated with saliva 2X and challenged with SGE plus parasite, referred to as SGE-3X, did not exhibit edema until the 7th week of infection. Furthermore, significantly lower numbers of parasites were detected on the 3rd and 7th week post-infection in mice that received SGE-3X when compared with mice that received parasite in SGE-1X (Figure 3B). In summary, our results are consistent with previous studies, which have shown that pre-exposure to saliva results in the protection against infection.