NK1.1(+) cells and murine cytomegalovirus infection: What happens in situ?

NK cells mediate early host defense against viral infection, In murine CMV (MCMV) infection NK cells play a critical role in controlling viral replica tion in target organs, such as spleen and liver, Until now it has not been possible to directly examine the role of NK cells in MCMV-induced inflammat ion in situ due to the inability to stain specifically for NK cells in infe cted tissues. In this study, we describe a method of in vivo fixation, resu lting in the first identification of NK cells In situ using NK1.1 as the ma rker. Using this method, we characterize the NK1.1(+) cellular component of the inflammatory response to wild-type MCMV in the spleen, liver, and lung of genetically susceptible and resistant mice following i.p. infection. Th is study provides the first in situ description of the cellular response me diated specifically by NK cells following MCMV infection.