Transcriptome of activated human and mouse MAIT cells

We sought to describe in detail the consequences of MAIT cell activation using a transcriptomic approach to define the basic transcriptome of a MAIT cell in both humans and mice and to determine how this is modulated by activation. Fresh human peripheral blood cells were obtained from three donors. These were cultured for 6 hours with ('stimulated') or without ('unstimulated') 10 nM 5-OP-RU, magnetically enriched on MR1-tetramer+ cells, and flow-sorted for RNA sequencing of live CD3+TCR Valpha7.2+ MR1-5-OP-RU tetramer+ MAIT cells, and of unstimulated naïve live CD8+CD45RA+ T cells as a comparator cell type. For the murine samples we included within the same sequencing experiment live pulmonary CD3+45.2+19-MR1-5-OP-RU tetramer+ MAIT cells which were magnetically enriched and flow-sorted from the lungs of mice 7 days after infection with 1x104 CFU L. longbeachae ('acute'), or at least 12 weeks post infection ('resolution') or 7 days after a second intranasal infection with 2x104 CFU L. longbeachae in mice that had recovered from infection 12 weeks previously ('reinfection'). Live CD3+CD45.2+CD19-CD8+CD44-CD62L+ naïve T cells from uninfected mice were used as a comparator cell type. Overall design: Illumina sequencing of human and murine MR1-5-OP-RU tetramer+ MAIT cells in comparison with naïve CD8 T cells. 3 biological replicates of each of the following conditions: Human peripheral blood MAIT cell unstimulated. Human peripheral blood MAIT cells stimulated for 6 h with 5-OP-RU. Human peripheral blood CD8+45RA+ T cells. Murine pulmonary MAIT cells 7 days after legionella infection, 12 weeks after legionella infection, 7 days after reinfection with legionella, Murine naive pulmonary CD8+CD45+44-62L+ T cells. Full details of the study can be downloaded at https://www.biorxiv.org/content/early/2018/12/09/490649?rss=1