Type 1 diabetes (T1D) is an incurable disease, often starting in childhood, with a risk of devastating complications, premature mortality, and high social burden. It is caused by the autoimmune destruction of insulin-producing beta cells, yet the standard of care is insulin replacement, acting only at the symptom level. Thus, T1D is a disease with a high unmet need for innovative therapy. Ideally, such therapy shall suppress selectively the immune cells driving T1D without impairing protective immunity. Regulatory T cells (Tregs) are the guardians of human immune tolerance, and genetic defects in Tregs are associated with T1D. Tregs additionally possess tissue regenerative capacity, making them ideal to treat T1D in cell therapy. However, such therapy, performed with polyclonally expanded patient Tregs, showed limited efficacy in T1D. These expanded Tregs are however poor in relevant autoreactive Tregs to save insulin-producing cells. In fact, the identification and manufacturing of autoreactive Tregs remain fundamental technical challenges to successfully apply these cells in the clinic. ARTiDe aims at a breakthrough in antigen-specific Treg therapy in T1D by establishing the production of human Tregs genetically engineered to express an autoreactive T cell antigen receptor (TCR) ready for clinical use. To achieve this ambitious goal, ARTiDe combines the complementary expertise of 8 partners providing novel technologies for the systematic identification of autoantigen-specific Tregs in humans, the selection of optimal TCR to produce protective Tregs, and innovative humanized T1D pre-clinical models to test their efficacy and safety, as well as Treg supporting strategies, in vivo. World-leading biotechs for adoptive T cell therapy will establish novel GMP-compatible manufacturing of highly purified TCR-engineered Tregs. ARTiDe will deliver a Treg production process and regulatory certificates that will allow launching a phase 1 clinical trial just after the project.

As major players in the regulation of immune responses, regulatory T cells (Tregs) are important therapeutic targets for autoimmune and inflammatory diseases. Interleukin-2 (IL-2) used at low doses (IL-2LD) stimulate and expand Tregs in vivo. While 1st-generation native IL-2LD are currently under extensive clinical evaluation, pharmaceutical companies are developing 2nd-generation IL-2 muteins with improved half-life and activity. We aim to develop 3rd-generation IL-2 specifically targeting inflammatory sites (IL-2IT) by using antibodies (Abs) against oxidation specific epitopes (OSE) that are both universal markers and mediators of inflammation. IL-2-OSE-Ab fusion proteins should allow dampening of local inflammation by a double-hit mechanism involving Ab neutralization of pro-inflammatory OSE and IL-2 stimulation of Tregs. As a proof of concept, we designed a first IL-2IT in which an IL-2N88R mutein is fused to an scFv from a prototypic anti-OSE Ab. This IL-2IT (i) binds to IL-2 receptors and OSE, (ii) has an extended half-life and (iii) superior therapeutic efficacy compared to native IL-2 in mice. Our general objectives are to design an optimized IL-2IT by testing combinations of different anti-OSE Ab with IL-2 and IL-2 muteins, and to complete its preclinical development in mice and macaques. We will validate the use of IL-2IT in cardiovascular diseases (CVD), i.e. atherosclerosis, vasculitis, myocardial infarction and SLE-associated CVD, as these conditions have been shown to be improved by Treg infusions, native IL-2 and OSE-Abs in mice. Carried by leading experts in the use IL-2, OSE-Abs, models of CVD, and clinical trials with native IL-2, the successful validation of an IL-2IT will open a new era for highly selective and effective immunotherapies based on Treg stimulation for diseases that represent a leading cause of death and morbidity. Furthermore, it will validate the broader concept of targeting any therapeutic molecule to inflammatory sites.

Objective: MOODSTRATIFICATION brings together 11 partners (psychiatrists, immunologists, epidemiologists, industry) from 7 countries stratifying patients with a major depressive episode on the basis of leukocyte immune profiles. The immune profiles were found in two previous EU projects, which also delivered the novel concept, that T cell defects with episodes of chronic mild inflammation are a causal factor for a large part of mood disorders. The immune profiles determine therapy choice with (combinations of) conventional and novel therapies with immune modulators (e.g. anti-inflammatory and T cell enforcement therapies). On the basis of recent data we expect that the present poor response rates of about 50% to anti-depressant therapy will improve considerably to 80-90%. Mood disorders are complex diseases with a high prevalence (12-20%) and are the second highest contributor to the number of years lived with disability worldwide. Work plan: MOODSTRATIFICATION firstly uses the large data sets and biobank of the two previous EU projects to further refine the already found immune profiles. Therefore the proposal further integrates existing and newly collected multidimensional, longitudinal clinical and laboratory data (-omics, FACS and serum multi-analytes) from these projects for further immune network analysis and computational modelling also taking female-male differences into account. Technologies to easily determine the immune profiles (a relatively small multi-analyte panel, Q-PCR kits on PAXGENE material) will together with industries be developed. Thereafter the efficacy of two novel T cell enforcing therapeutic approaches and the new concept of depression stratification on the basis of the immune profiles will be validated in three clinical proof-of-principle studies. Various national and international patient associations will be actively involved. Novelty: This is the first lab-based therapy stratification in psychiatry made ready for the clinic.

Regulatory T cells (Tregs) are important therapeutic targets for many immunopathologies. Stimulating Tregs with interleukin-2 (IL-2), the key cytokine supporting Treg fitness, is being actively developed, but is likely to be insufficient to achieve optimal therapeutic efficacy in severe diseases. This is why many groups are developing Treg cell-based therapies, harnessing the experience accumulate during the development of CAR T cell therapies for cancer. In this emerging field, we propose to develop an innovation aimed at generating enhanced-Tregs (e.Tregs) by rendering them IL-2 self-sufficient. We have already proven that, compared to control Tregs, e.Tregs expressing a mutated IL-2 (IL-2N88R) that cannot activate Teffs (i) survive much better in IL-2 deprived environments, (ii) are more stable in phenotype and (iii) have a much better therapeutic efficacy. We will complete the preclinical development of e.Tregs and perform a first-in-man dose-escalation phase-I/II study in chronic graft-versus-host-disease (cGVHD).For this purpose, we will (i) finalize the optimal design of the lentiviral vector to be used, including addition of a suicide gene; (ii) optimize the entire process to select, gene-modify and expand Tregs under good manufacturing practices (GMP) and (iii) perform a dose-escalation phase 1/2 study in patients with cGVHD. The partners are experts in stem cell transplantation and cell therapy who have developed their own academic production of CAR T cells for leukaemia, used in more than 400 patients. They will translate their know-how to e.Tregs.We aim to validate a new therapeutic approach for the treatment of cGVHD, a condition with high mortality and morbidity and unmet clinical needs. Furthermore, we expect that our results will motivate researchers to harness the e.Treg technology in their products, notably CAR Tregs.This should have a major impact by enabling more effective therapies for high-burden diseases or disorders with unmet medical needs.

As major players in the regulation of immune responses, regulatory T cells (Tregs) are important therapeutic targets for autoimmune and inflammatory diseases. Interleukin-2 (IL-2) used at low doses (IL-2LD) stimulate and expand Tregs in vivo. While 1st-generation native IL-2LD are currently under extensive clinical evaluation, pharmaceutical companies are developing 2nd-generation IL-2 muteins with improved half-life and activity. We aim to develop 3rd-generation IL-2 specifically targeting inflammatory sites (IL-2IT) by using antibodies (Abs) against oxidation specific epitopes (OSE) that are both universal markers and mediators of inflammation. IL-2-OSE-Ab fusion proteins should allow dampening of local inflammation by a double-hit mechanism involving Ab neutralization of pro-inflammatory OSE and IL-2 stimulation of Tregs. As a proof of concept, we designed a first IL-2IT in which an IL-2N88R mutein is fused to an scFv from a prototypic anti-OSE Ab. This IL-2IT (i) binds to IL-2 receptors and OSE, (ii) has an extended half-life and (iii) superior therapeutic efficacy compared to native IL-2 in mice. Our general objectives are to design an optimized IL-2IT by testing combinations of different anti-OSE Ab with IL-2 and IL-2 muteins, and to complete its preclinical development in mice and macaques. We will validate the use of IL-2IT in cardiovascular diseases (CVD), i.e. atherosclerosis, vasculitis, myocardial infarction and SLE-associated CVD, as these conditions have been shown to be improved by Treg infusions, native IL-2 and OSE-Abs in mice. Carried by leading experts in the use IL-2, OSE-Abs, models of CVD, and clinical trials with native IL-2, the successful validation of an IL-2IT will open a new era for highly selective and effective immunotherapies based on Treg stimulation for diseases that represent a leading cause of death and morbidity. Furthermore, it will validate the broader concept of targeting any therapeutic molecule to inflammatory sites.