DH82 Canine and RAW264.7 Murine Macrophage Cell Lines Display Distinct Activation Profiles Upon Interaction With Leishmania infantum and Leishmania amazonensis .

Leishmaniasis is an anthropozoonotic disease, and dogs are considered the main urban reservoir of the parasite. Macrophages, the target cells ofLeishmania sp., play an important role during infection. Although dogs have a major importance in the epidemiology of the disease, the majority of the current knowledge aboutLeishmania-macrophage interaction comes from murine experimental models. To assess whether the canine macrophage strain DH82 is an accurate model for the study ofLeishmaniainteraction, we compared its infection by two species ofLeishmania(Leishmania infantumandL. amazonensis) with the murine macrophage cell line (RAW264.7). Our results demonstrated thatL. amazonensissurvival was around 40% at 24 h of infection inside both macrophage cell lines; however, a reduction of 4.3 times inL. amazonensisinfection at 48 h post-infection in RAW 264.7 macrophages was observed. The survival index ofL. infantumin DH82 canine macrophages was around 3 times higher than that in RAW264.7 murine cells at 24 and 48 h post-infection; however, at 48 h a reduction in both macrophages was observed. Surprisingly at 24 h post-infection, NO and ROS production by DH82 canine cells stimulated with LPS or menadione or duringLeishmaniainfection was minor compared to murine RAW264.7. However, basal arginase activity was higher in DH82 cells when compared to murine RAW264.7 cells. Analysis of the cytokines showed that these macrophages present a different response profile.L. infantuminduced IL-12, andL. amazonensisinduced IL-10 in both cell lines. However,L. infantum and L. amazonensisalso induced TGF-beta in RAW 264.7. CD86 and MHC expression showed thatL. amazonensismodulated them in both cell lines. Conversely, the parasite load profile did not show significant difference between both macrophage cell lines after 48 h of infection, which suggests that other mechanisms ofLeishmaniacontrol could be involved in DH82 cells.