Tom Enbar

Current cancer immunotherapy predominately focuses on eliciting type 1 immune responses fighting cancer; however, long-term complete remission remains uncommon1,2. A pivotal question arises as to whether type 2 immunity can be orchestrated alongside type 1-centric immunotherapy to achieve enduring response against cancer3,4. Here we show that an interleukin-4 fusion protein (Fc–IL-4), a typical type 2 cytokine, directly acts on CD8+ T cells and enriches functional terminally exhausted CD8+ T (CD8+ TTE) cells in the tumour. Consequently, Fc–IL-4 enhances antitumour efficacy of type 1 immunity-centric adoptive T cell transfer or immune checkpoint blockade therapies and induces durable remission across several syngeneic and xenograft tumour models. Mechanistically, we discovered that Fc–IL-4 signals through both signal transducer and activator of transcription 6 (STAT6) and mammalian target of rapamycin (mTOR) pathways, augmenting the glycolytic metabolism and the nicotinamide adenine dinucleotide (NAD) concentration of CD8+ TTE cells in a lactate dehydrogenase A-dependent manner. The metabolic modulation mediated by Fc–IL-4 is indispensable for reinvigorating intratumoural CD8+ TTE cells. These findings underscore Fc–IL-4 as a potent type 2 cytokine-based immunotherapy that synergizes effectively with type 1 immunity to elicit long-lasting responses against cancer. Our study not only sheds light on the synergy between these two types of immune responses, but also unveils an innovative strategy for advancing next-generation cancer immunotherapy by integrating type 2 immune factors. Fc–IL-4, a typical type 2 cytokine, reinvigorates exhausted CD8+ T cells in tumours, underscoring this fusion protein as a potent immunotherapy that synergizes effectively with type 1 immunity against cancer.

Abstract Current cell therapies are limited by the lack of tools for controlling gene expression using humanized systems responsive to non-toxic stimuli. Starting from nanobodies that homodimerize in response to caffeine, we computationally designed inducible heterodimers and humanized the best-performing pairs. We used the resulting caffeine-inducible domains in engineered cytokine receptors for caffeine-inducible STAT3 signaling and in split transcription factors (caff-TFs) containing human-derived zinc-finger proteins. Heterodimerization of split transcription factors drastically enhanced their performance compared to homodimerization. We demonstrate that caff-TFs are compatible with lentiviral and retroviral delivery to Jurkat T-cells and enable inducible expression of therapeutic genes such as chimeric antigen receptors (CARs) in response to caffeine concentrations consistent with normal coffee consumption. By using the common, non-toxic molecule caffeine, and exclusively humanized protein components, these systems promise to be a safer alternative to existing systems and may be used in synthetic biology applications and for safer, more effective cell therapies.

Abstract Cytokines are key signal mediators of the immune system, playing essential roles in regulating central immunological processes. Despite their unique ability to modulate the immune system, the translation of cytokine-based therapies to the clinic has been significantly hindered by severe toxicities resulting from the pleiotropy and off-target effects of many cytokines. Here, we present a general strategy for the design of switchable cytokines that enables precise control over cytokine activity using the clinically approved drug, Venetoclax. We rationally designed self-inhibited Sw itchable I nter L eukins (SwILs) by embedding the chemically controlled interface (Bcl-2: BIM-BH3) into the cytokine’s structure, resulting in conditional cytokines activated by Venetoclax. We showed the broad applicability of this strategy across various cytokines, including IL-2, IL-15, and IL-10. In vivo studies with IL-15 demonstrated that the SwILs achieved Venetoclax-dependent tumor control comparable to that of the native cytokine. Additionally, we showed that this strategy can be expanded to respond to other tumor-intrinsic stimuli, such as tumor-specific proteases. Overall, SwILs offer control of cytokine activity, enhancing the safety and clinical applicability of cytokine-based therapeutics.