A novel GPI-anchored dominant-negative TGF-β receptor II renders T cells unresponsive to TGF-β signaling

Sven H Petersen; Kays Al Badawy; Richard Hopkins; Dang L Vu; Mehran Rahmani; Sonia M P Maia; John E Connolly

doi:10.1016/j.omto.2023.100730

A novel GPI-anchored dominant-negative TGF-β receptor II renders T cells unresponsive to TGF-β signaling

Mol Ther Oncolytics. 2023 Sep 25:31:100730. doi: 10.1016/j.omto.2023.100730. eCollection 2023 Dec 19.

Authors

Sven H Petersen¹, Kays Al Badawy¹, Richard Hopkins¹, Dang L Vu^{1

2}, Mehran Rahmani¹, Sonia M P Maia^{1

2}, John E Connolly^{1

2

3

4

5}

Affiliations

¹ Tessa Therapeutics, Singapore, Singapore.
² Program in Translational Immunology, Institute of Molecular and Cell Biology, A∗STAR, Singapore, Singapore.
³ Department of Microbiology and Immunity, National University of Singapore, Singapore, Singapore.
⁴ Institute of Biomedical Studies, Baylor University Medical Center, Waco, TX, USA.
⁵ Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA.

Abstract

Transforming growth factor β (TGF-β) is a pleiotropic cytokine expressed by a wide range of cell types and is known for hampering the effectiveness of cancer immune cell therapeutic approaches. We have designed a novel construct containing the extracellular domain of the TGF-β receptor II linked to a glycosylphosphatidylinositol (GPI) anchor (GPI-ecto-TβRII) lacking the transmembrane and cytoplasmic signaling domain of TGF-β receptor II (TβRII). T cells transduced with lentivirus expressing the GPI-ecto-TβRII construct show 5 to 15 times higher membrane expression compared with a previously established dominant-negative receptor carrying a truncated signaling domain. GPI-ecto-TβRII expression renders T cells unresponsive to TGF-β-induced signaling seen by a lack of SMAD phosphorylation upon exogeneous TGF-β treatment. Transduced T cells continue to express high levels of IFNγ and granulocyte-macrophage colony-stimulating factor (GM-CSF), among other cytokines, in the presence of TGF-β while cytokine expression in untransduced T cells is being markedly suppressed. Furthermore, T cells expressing GPI-ecto-TβRII constructs have been shown to efficiently capture and inactivate TGF-β from their environment. These results indicate the potential benefits of GPI-ecto-TβRII expressing cytotoxic T cells (CTLs) in future cell therapies.

Keywords: T cell; TGF-β; cancer; cell therapy; decoy receptor; tumor growth factor beta; tumor microenvironment.