Healing of @entity232 is dependent on activation of parasitized macrophages (Mphi) by IFN-gamma, which is secreted by @entity3667 -specific Th1 cells. IL-12 enhances IFN-gamma production by Th1 cells and is crucial for cure. The host cells of @entity3667 sp., Mphi, are a main source of IL-12 in vivo. We report that @entity281 of quiescent @entity19 Mphi with L. mexicana or @entity3667 amastigotes does not induce IL-12 production. Moreover, @entity281 suppresses IL-12 secretion by Mphi activated by @entity558 , by CD40 cross-linking or cognate interaction with Th1 cells. IL-12 secretion is also suppressed in Mphi activated after phagocytosis of latex beads. Suppression is independent of engagement of CR3 or FcgammaR during phagocytosis, is not mediated by IL-10 and does not alter steady state IL-12p40 mRNA levels. In addition, suppression of IL-12 secretion does not depend on Mphi activation concurrent to @entity281 . In contrast, NO production was not inhibited. Thus, Mphi effector functions are differentially affected and this may be a general effect of phagocytosis of non-activating particles. The possible implications of this effect on the @entity281 are discussed.

Phagocytosis of XXXX mexicana amastigotes by macrophages leads to a sustained suppression of IL-12 production.

@entity558 :: ('MESH:C536528', 'Disease') :: ['LPS'] @entity19 :: ('10090', 'Species') :: ['murine'] @entity232 :: ('MESH:D007896', 'Disease') :: ['leishmaniases'] @entity3667 :: ('5664', 'Species') :: ['L. major', 'Leishmania'] @entity281 :: ('MESH:D007239', 'Disease') :: ['infection']
@entity3667 :: (5664,Species) :: ['Leishmania']
