Project description:V(D)J recombination initiated by recombination-activating gene (RAG) endonucleases is a crucial process for the generation of diversified antigen receptors of T and B lymphocytes but regarded dispensable for the generation of innate natural killer (NK) lymphocytes that lack clonotypic receptors. However, a fraction of human and murine NK cells derives from RAG-expressing progenitors, which have non-productive rearrangements within their Ig and TCR loci. An impact of V(D)J rearrangements on maturation and function of NK cells has been suggested by mouse and human models. We studied the impact of RAG expression ontogeny on NK cell maturation and function by using RAG-fate mapping reporter permanently labeling NK progenitors and mature NK cells.
Project description:Investigation of global gene expression levels between B cells, Natural killer cells and Natural killer B cells Gene expression profiling using sorted B cells, Natural killer cells and Natural killer B cells from WT mouse spleen. Total RNA extracted from WT cells were quantified by the NanoDrop ND-1000 and RNA integrity was assessed by standard denaturing agarose gel electrophoresis. The sample preparation and microarray hybridization were performed based on the NimbleGenâs standard protocols.
Project description:Comparing global gene expression of neonatal and adult natural killer cells to determine if differences in gene expression suggest that different developmental pathways during hematopoiesis are followed in the fetal and adult mouse to produce mature natural killer cells.
Project description:The emergence of recombination-activating genes (RAGs) in jawed vertebrates endowed adaptive immune cells with the ability to assemble a diverse set of antigen receptor genes. In contrast, innate lymphocytes, such as natural killer (NK) cells, are not believed to require RAGs. Here, we report that NK cells unable to express RAGs or RAG endonuclease activity during ontogeny exhibit a cell-intrinsic hyperresponsiveness but a diminished capacity to survive following virus-driven proliferation, a reduced expression of DNA damage response mediators, and defects in the repair of DNA breaks. Evidence for this novel function of RAG has also been observed in T cells and innate lymphoid cells (ILCs), revealing an unexpected role for RAG proteins beyond V(D)J recombination. We propose that DNA cleavage events mediated by RAG endow developing adaptive and innate lymphocytes with a cellular "fitness" that safeguards their persistence later in life during episodes of rapid proliferation or cellular stress.
Project description:Natural killer cells were exptracted from PMBCs of healthy donors, exposed to arachidonic acid, Il-2, both, or ascites and their expression changes identified via RNAseq (QuantSeq).