Long-Term MALT1 Inhibition in Adult Mice Without Severe Systemic Autoimmunity

Annelies Demeyer; Yasmine Driege; Ioannis Skordos; Julie Coudenys; Kelly Lemeire; Dirk Elewaut; Jens Staal; Rudi Beyaert

doi:10.1016/j.isci.2020.101557

Long-Term MALT1 Inhibition in Adult Mice Without Severe Systemic Autoimmunity

iScience. 2020 Sep 12;23(10):101557. doi: 10.1016/j.isci.2020.101557. eCollection 2020 Oct 23.

Authors

Annelies Demeyer^{1

2}, Yasmine Driege^{1

2}, Ioannis Skordos^{1

2}, Julie Coudenys^{1

3}, Kelly Lemeire^{1

2}, Dirk Elewaut^{1

3}, Jens Staal^{1

2}, Rudi Beyaert^{1

2}

Affiliations

¹ Center for Inflammation Research, VIB, Technologiepark-Zwijnaarde 71, 9052 Ghent, Belgium.
² Department of Biomedical Molecular Biology, Ghent University, Technologiepark-Zwijnaarde 71, 9052 Ghent, Belgium.
³ Department of Internal Medicine and Pediatrics, Ghent University, Technologiepark-Zwijnaarde 71, 9052 Ghent, Belgium.

Abstract

The protease MALT1 is a key regulator of NF-κB signaling and a novel therapeutic target in autoimmunity and cancer. Initial enthusiasm supported by preclinical results with MALT1 inhibitors was tempered by studies showing that germline MALT1 protease inactivation in mice results in reduced regulatory T cells and lethal multi-organ inflammation due to expansion of IFN-γ-producing T cells. However, we show that long-term MALT1 inactivation, starting in adulthood, is not associated with severe systemic inflammation, despite reduced regulatory T cells. In contrast, IL-2-, TNF-, and IFN-γ-producing CD4⁺ T cells were strongly reduced. Limited formation of tertiary lymphoid structures was detectable in lungs and stomach, which did not affect overall health. Our data illustrate that MALT1 inhibition in prenatal or adult life has a different outcome and that long-term MALT1 inhibition in adulthood is not associated with severe side effects.

Keywords: Cell Biology; Immunology.