Liver-resident NK cell immune negative function reveals
Liver-resident NK cell immune negative function reveals February 22, 2019 Source: Science and Technology Daily Author: Wu Changfeng The reporter learned from the University of Science and Technology on the 21st that the research team of the Academician Tian Zhigang of the Department of Life Science and Medicine of the school found that the liver-resident NK cells can negatively regulate the antiviral immune response of T cells and its mechanism. The results of the "immunization", the top journal of immunology in the Cell Publishing Group, was published recently. The liver has a unique immune tolerance property and is the main site for many viruses to replicate in the body. Liver T cells often cannot produce an effective immune response to eliminate the virus and cause persistent infection of the virus. However, the regulatory mechanisms of low antiviral capacity of liver T cells are not well understood. Professor Tian Zhigang's research group reported for the first time in 2013 that there is a unique group of resident NK cells in the liver of adult mice. Compared with the classical NK (cNK) cells in the peripheral circulation, this special LrNK cell of the liver has different regulation mechanisms of phenotypic development and differentiation, and the expression of effector molecules is also different. The results of transcriptomics suggest that LrNK cells predominantly express immunosuppression and tolerance-inducing genes relative to cNK cells. Given that liver immune tolerance is closely related to low T cell response, whether LrNK cells can maintain liver immune tolerance by regulating T cell responses has become an important starting point for this study. The researchers used LrNK cell-deficient mice to conduct experiments, and found that after virus infection of the defective mice, the T cells function in the liver of the mice was enhanced, and the virus titer was reduced. Exogenously transfected LrNK cells in normal mice or LrNK cell-deficient mice can inhibit the antiviral T cell response in the liver, and cNK cells can promote T cell responses. In vitro and in vivo experiments further revealed that LrNK cells rely on PD-L1 on their surface to exert functional inhibition of T cells in the liver. This results systematically elucidated the completely opposite function of LrNK and cNK cells in regulating T cell responses, suggesting that LrNK cells play an important role in the maintenance of liver immune tolerance microenvironment, for understanding the composition of NK cell subsets and shaping regional immune characteristics. The intrinsic link between them provides a new basis. Household Gloves,Gloves Microfiber,Flock Lined Glove,Household Latex Work Glove ZHANGJIAGANG DINSHENGLIN TRADING CO.,LTD , https://www.dslhouse.com