CD1d-independent regulation of NKT cell migration and cytokine production upon Listeria monocytogenes infection

Natural killer T (NKT) cells are a unique T-cell population that is positively selected by CD1d-expressing cells. In this study, we examined the kinetics of conventional CD4(+)TCR beta(+) and CD4(-)TCR beta(+) cells along with various NKT cell populations from WT and CD1d KO mice after oral Listeria monocytogenes (Lm) infection at different time points in tissue compartments. We found that CD4(+)TCR beta(+) cells expressing NK1.1(+) (NKT) were constitutively expressed in the lung of both strains of mice, but disappeared after infection. In contrast, CD4(-)TCR beta(+) NK1.1(+) cells migrated to the spleen. Here, we demonstrated that endogenous IL-12 was predominantly expressed in the spleen of CD1d KO mice 2 days after infection, whereas IL-4 was predominantly expressed in the liver of WT mice. Higher levels of IFN-gamma were expressed in MLN of CD1d KO but not in WT mice on day 5. Thus, tissue-specific ligands orchestrate the localization and activation of NKT cells to control immune response to Listeria, which may explain the difference in disease susceptibility. (c) 2005 Elsevier Inc. All rights reserved.