Histone methyltransferase DOT1L maintains identity and restricts cytotoxic potential of CD8 T cells

Malik, M.; de Leeuw, W.-J.; Aslam, M. A.; Kwesi-Maliepaard, E. M.; van den Brand, T. A.; van den Broek, B.; Kempers, M.; Hoekman, L.; Proost, N.; van Welsem, T.; de Wit, E.; Borst, J.; Jacobs, H.; van Leeuwen, F.

doi:10.1101/2025.01.20.633937

bioRxiv · 10.1101/2025.01.20.633937

Histone methyltransferase DOT1L maintains identity and restricts cytotoxic potential of CD8 T cells

Malik, M.·de Leeuw, W.-J.·Aslam, M. A.·Kwesi-Maliepaard, E. M.·van den Brand, T. A.·van den Broek, B.·Kempers, M.·Hoekman, L.·Proost, N.·van Welsem, T.·de Wit, E.·Borst, J.·Jacobs, H.·van Leeuwen, F.

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Abstract

The histone methyltransferase DOT1L is emerging as a central epigenetic regulator in immune cells. Loss of DOT1L during development of CD8 T cells in vivo leads to gain of memory-features but has also been reported to compromise CD8 T cell viability and activity. Here, we determined the cell-intrinsic role of DOT1L in mature mouse CD8 T cells. After conditional deletion of Dot1L in vitro, CD8 T cells retained in vivo proliferative capacity and anti-tumor reactivity. Moreover, Dot1L knock-out CD8 T cells showed increased antigen-specific cytotoxicity towards tumor cells in vitro. Mechanistically, loss of DOT1L resulted in an altered cell-identity program with loss of T-cell and gain of NK-cell features. These transcriptional changes were mediated by loss of DOT1L methyltransferase activity in a dose-dependent manner. Our findings show that ablation of DOT1L activity in mature CD8 T cells is well-tolerated and rewires their cell identity towards the NK-cell lineage, concomitantly enhancing intrinsic cytotoxic capacity. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=143 SRC="FIGDIR/small/633937v1_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@1641c55org.highwire.dtl.DTLVardef@1803510org.highwire.dtl.DTLVardef@1bedceorg.highwire.dtl.DTLVardef@199a6d5_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIDifferentiation and identity of cytotoxic T cells depend on the methyltransferase DOT1L C_LIO_LIDOT1L intrinsically limits the cytotoxic activity of mature CD8 T cells C_LIO_LIDOT1L prohibits the acquisition of NK cell features in CD8 T cells C_LIO_LIDOT1L maintains CD8 T cell identity through its catalytic activity in a dose-dependent manner C_LI

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Malik, M., de Leeuw, W.-J., Aslam, M. A., Kwesi-Maliepaard, E. M., van den Brand, T. A., van den Broek, B., Kempers, M., Hoekman, L., Proost, N., van Welsem, T., de Wit, E., Borst, J., Jacobs, H., van Leeuwen, F.. 2025-01-22. Histone methyltransferase DOT1L maintains identity and restricts cytotoxic potential of CD8 T cells. https://doi.org/10.1101/2025.01.20.633937

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