Natural killer cells are innate lymphocytes found throughout the human body. Recent data from mouse experiments suggest that most NK cells present in peripheral organs are permanent residents of these organs. However, this remains unclear in the human setting. In the current project we have characterised NK cells in human uterus after uterus transplantation using 10x genomics coupled to RNAseq. Based on SNP-calling we will determine the origin of the uterine NK cells, if they are donor or recipient derived.