Absence of CD38 delays arrival of neutrophils to the liver and innate immune response development during hepatic amoebiasis by Entamoeba histolytica.

To define the role of CD38 in the migration of neutrophils to the liver and consequently in the induction of an innate immune response during murine hepatic amoebiasis by Entamoeba histolytica, we examined amoebic liver abscess development (ALA), presence of amoebae and neutrophils, and expression levels of cytokines and other inflammation mediators mRNA, in infected wild-type and CD38 Knockout (CD38KO) C57BL/6J mice. Results showed that CD38KO mice undergo a delay in ALA development in comparison with the wild-type strain. The presence of amoebae lasted longer in CD38(-/-), and although neutrophils arrived to the liver in both strains, there was a clear difference in the time between the two strains; whereas in the wild-type strain, neutrophils arrived at early times (6-12 h), in the CD38KO strain, neutrophils arrived later (48-72 h). Cytokines profile during the innate immune response development (TNF-α, IL-1β, IL-6) was, for WT mice concomitant with, and preceded, for CD38KO mice, the time in which neutrophils were present in the liver lesion. In conclusion, CD38 is important for neutrophils migration during hepatic amoebiasis, and in turn, these cells play an important role in the innate immune response.