CD163 and infection: The initial M1 polarization was also observed by Ontoria et al. when monitoring polarization in L. infantum-infected spleen cells of BALB/c mice [63], whereas in natural infections, VL normally correlates with high M2 polarization, characterized by increased arginase levels in the blood [64] and soluble CD163 in human [65,66] and canine VL [67].