Abstract
The transcriptional activation and repression during NK cell ontology are poorly understood. Here, using single-cell RNA-sequencing, we reveal a novel role for T-bet in suppressing the immature gene signature during murine NK cell development. Based on transcriptome, we identified five distinct NK cell clusters and define their relative developmental maturity in the bone marrow. Transcriptome-based machine-learning classifiers revealed that half of the mTORC2-deficient NK cells belongs to the least mature NK cluster. Mechanistically, loss of mTORC2 results in an increased expression of signature genes representing immature NK cells. Since mTORC2 regulates the expression of T-bet through AktS473-FoxO1 axis, we further characterized the T-bet-deficient NK cells and found an augmented immature transcriptomic signature. Moreover, deletion of Foxo1 restores the expression of T-bet and corrects the abnormal expression of immature NK genes. Collectively, our study reveals a novel role for mTORC2-AktS473-FoxO1-T-bet axis in suppressing the transcriptional signature of immature NK cells.
Highlights
NK cells are type one innate lymphoid cells known for their function in mediating both cytotoxicity and cytokine production in response to transformed or virally-infected cells (Sun and Lanier, 2011; Vivier et al, 2008)
When we focused on the analysis of NK cells, the differential expressed genes (DEGs) and module scores based on DEGs of immature NK (iNK) and terminally mature NK (termNK) of combined wide type (WT) analysis indicated that Cluster #1 and #4 represent the iNK and termNK in the Rictorfl/fl Ncr1WT/WT mouse, respectively, with Cluster #2 and #3 being the transitional stages (Figure 3E and Supplementary file 3)
Based on the transcriptome information of the WT clusters, we utilized the machine-learning classifiers to define the identity of Raptor- or Rictor-deficient NK cells and found maturation profiles of these mutant NK cells distinct from the cell surface markers-based definition that we previously reported (Yang et al, 2018)
Summary
NK cells are type one innate lymphoid cells known for their function in mediating both cytotoxicity and cytokine production in response to transformed or virally-infected cells (Sun and Lanier, 2011; Vivier et al, 2008). In the bone marrow (BM) of mice, the expression of IL-15/IL-2 receptor b chain (CD122) is the hallmark of commitment to the NK cell lineage from the common lymphoid progenitor (CLP) cells (Rosmaraki et al, 2001). The canonical definition of NK progenitor (NKP) is a. The LinÀCD122+NK1.1À cells are still a heterogeneous population as approximately only one in ten cells can give rise to NK cells in vitro (Vosshenrich and Di Santo, 2013). The definition of NKPs has been refined to LinÀFlt3ÀCD27+2B4+CD127+CD122+NK1.1À cells which have a 50% chance to develop into NK cells in vitro (Carotta et al, 2011; Fathman et al, 2011). The other lineage cell type in the heterogenous LinÀCD122+NK1.1À population is yet to be fully-defined
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
