Characterization of lacrimal gland NK cells (P4341)

Abstract

Abstract The β-herpes virus murine cytomegalovirus (MCMV), a homologue of HCMV, is a well-characterized animal model of viral infection that results in a non-replicative, chronic infection of an immune-competent animal. MCMV is cleared efficiently by cytotoxic lymphocytes in most organs of the infected host but persists in salivary glands for several weeks after primary infection. Interestingly, it has also been shown that MCMV remains active in the lacrimal gland (LG) for several weeks after infection. Here, we investigate the phenotype of NK cells in the naïve LG and their response to MCMV infection. In naïve mice, we found that the LG contains a resident NK cell population with a mostly immature phenotype (CD27 high/CD11b low). These lymphocytes are absent in E4BP4 deficient mice and present in AhR deficient mice, indicating that these cells belong to the classical NK cell lineage. However, using a variety of cell surface markers we found that the phenotype of LG NK cells is distinct from splenic, liver, or salivary gland NK cells suggesting that the NK cell peripheral phenotype is shaped by the tissue microenvironment. LG NK cells become activated during MCMV infection and release low amount of cytokines. We are currently evaluating in more details the role of LG NK cells during MCMV infection.