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T-cell recruiting bispecific antibodies (BsAbs) are in clinical development for relapsed/refractory acute myeloid leukemia (AML). Despite promising results, early clinical trials have failed to demonstrate durable responses. We investigated whether activation of the innate immune system through stimulator of interferon genes (STING) can enhance target-cell killing by a BsAb targeting CD33 (CD33 BiTE® molecule, AMG 330). Indeed, we show that cytotoxicity against AML mediated by AMG 330 can be greatly enhanced when combined with the STING agonist 2',3'-cyclic GMP-AMP (cGAMP), or diABZI. We used in vitro cytotoxicity assays, immunoblotting, transcriptomic analyses, and extensive CRISPR-Cas9 knockout experiments to investigate the enhancing effect of a STING agonist on the cytotoxicity of AMG 330 against AML. Importantly, we validated our findings with primary AML cells, and in a xenograft AML model. Mechanistically, in addition to direct cytotoxic effects of STING activation on AML cells, activated T cells render AML cells more susceptible to STING activation through their effector cytokines interferon-gamma (IFNγ) and tumor necrosis factor (TNF), resulting in enhanced type I interferon production and induction of interferon-stimulated genes. This feeds back to the T cells, leading to a further increase in effector cytokines and an overall cytotoxic T-cell phenotype, contributing to the beneficial effect of cGAMP/diABZI in enhancing AMG 330-mediated lysis. We established a key role for IFNγ in AMG 330-mediated cytotoxicity against AML cells, and in rendering AML cells responsive to STING agonism. Here, we propose to improve the efficacy of CD33-targeting BsAbs by combining them with a STING agonist., (Copyright © 2025 American Society of Hematology.)

Local translation regulates the axonal proteome, playing an important role in neuronal wiring and axon maintenance. How axonal mRNAs are localized to specific subcellular sites for translation, however, is not understood. Here we report that RNA granules associate with endosomes along the axons of retinal ganglion cells. RNA-bearing Rab7a late endosomes also associate with ribosomes, and real-time translation imaging reveals that they are sites of local protein synthesis. We show that RNA-bearing late endosomes often pause on mitochondria and that mRNAs encoding proteins for mitochondrial function are translated on Rab7a endosomes. Disruption of Rab7a function with Rab7a mutants, including those associated with Charcot-Marie-Tooth type 2B neuropathy, markedly decreases axonal protein synthesis, impairs mitochondrial function, and compromises axonal viability. Our findings thus reveal that late endosomes interact with RNA granules, translation machinery, and mitochondria and suggest that they serve as sites for regulating the supply of nascent pro-survival proteins in axons., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Allergic diseases have emerged as a major health care burden, especially in the western hemisphere. They are defined by overshooting reactions of an aberrant immune system to harmless exogenous stimuli. The T H 1/T H 2 paradigm assumes that a dominance of T H 2 cell activation and an inadequate T H 1 cell response are responsible for the development of allergies. However, the characterization of additional T helper cell subpopulations such as T H 9, T H 17, T H 22, T H GM-CSF and their interplay with regulatory T cells suggest further layers of complexity. This review summarizes state-of-the-art knowledge on T cell diversity and their induction, while revisiting the T H 1/T H 2 paradigm. With respect to these numerous contributors, it offers a new perspective on the pathogenesis of asthma, allergic rhinitis (AR) and atopic dermatitis (AD) incorporating recent discoveries in the field of T cell plasticity., (Copyright © 2016 Elsevier Inc. All rights reserved.)