Journal of Immunotoxicology最新文献

The skin is the organ most often affected by adverse drug reactions. Although these cutaneous adverse drug reactions (CADRs) often are mild, they represent a major burden for patients. One of the drugs inducing CADRs is aldesleukin, a recombinant interleukin-2 (recIL-2) originally approved to treat malignant melanoma and metastatic renal cell carcinoma which frequently led to skin rashes when applied in high doses for anti-cancer therapy. Skin rashes and other side effects, together with poor efficacy led to a drawback of the therapeutic, but modified recIL-2 molecules are on the rise to treat both cancer and inflammatory diseases such as autoimmunity. Still, pathophysiological mechanisms of recIL-2-induced skin rashes are not understood. In the study reported here, a hypothetical literature-based immune-related adverse outcome pathway (irAOP) was developed to identify possible key cells and molecules in recIL-2-induced skin rash. Using this approach, a hypothesis was formed that the induced immune response predominantly is Type 2-driven by T-helper and innate lymphoid cells, leading to the occurrence of cutaneous side effects during recIL-2 therapy. This paper further discusses mechanisms beyond the proposed irAOP which might add to the pathology but currently are less-studied. Together, this hypothetic irAOP forms a basis to clarify possible cellular and molecular interactions leading to recIL-2-induced skin rash. This might be used to adapt existing or develop new test systems to help predict and prevent cutaneous side effects in future IL-2-based or similar therapies.

This work focuses on the need for modeling and predicting adverse outcomes in immunotoxicology to improve nonclinical assessments of the safety of immunomodulatory therapies. The integrated approach includes, first, the adverse outcome pathway concept established in the toxicology field, and, second, the systems medicine disease map approach for describing molecular mechanisms involved in a particular pathology. The proposed systems immunotoxicology workflow is illustrated with chimeric antigen receptor (CAR) T cell treatment as a use case. To this end, the linear adverse outcome pathway (AOP) is expanded into a molecular interaction model in standard systems biology formats. Then it is shown how knowledge related to immunotoxic events can be integrated, encoded, managed, and explored to benefit the research community. The map is accessible online at https://imsavar.elixir-luxembourg.org via the MINERVA Platform for browsing, commenting, and data visualization. Our work transforms a graphical illustration of an AOP into a digitally structured and standardized form, featuring precise and controlled vocabulary and supporting reproducible computational analyses. Because of annotations to source literature and databases, the map can be further expanded to match the evolving knowledge and research questions.

The chances and opportunities in modern biology inspired devising new therapeutics are mind blowing. The promises reach from successfully treating so-far incurable diseases like cancer and certain infections, to modulating and fine tuning the immune response to prolong the lifespan by inhibiting aging. However, as underlying therapies become more and more complex and sophisticated, it becomes increasingly difficult to find ways to ensure and predict the safety of these new therapeutics. The ICH guideline S6 (R1) from June 2011 EMA/CHMP/ICH/731268/ 1998 Committee for Medicinal Products for Human Use (CHMP) already stated "Conventional approaches to toxicity testing of pharmaceuticals may not be appropriate for biopharmaceuticals due to the unique and diverse structural and biological properties of the latter that may include species specificity, immunogenicity, and unpredicted pleiotropic activities" and is committed to a "flexible, case-by-case, science-based approach to preclinical safety evaluation". Initial approaches to this are described in the OECD Test Guidelines for new approach methods (NAM) with the newest update released in 2023 and alternative non-animal test guidelines (https://www.icapo.org/test-guidelines) provided from the International Council on Animal Protection in OECD Programmes (ICAPO; https://www.icapo.org). Beyond that, the European Union-funded innovative medicine initiative project Immune Safety Avatar (imSAVAR) decided to develop a systematic and holistic framework for non-clinical safety assessment of biopharmaceuticals and Advanced Therapy Medicinal Products (ATMP); thereby, the consortium focuses on immuno-regulatory therapeutics. Science-based approaches, such as the mechanistic description of adverse outcomes would be essential to demonstrate the safety of a particular new immuno-therapeutic agent. Here, we re-use the concept of adverse outcome pathways (AOP) to capture immune-related adverse outcomes (irAO), which are aimed to guide us to the use of relevant test systems and experiments. Thus, the focus within imSAVAR is on the use and (further) develop-ment of human and alternative models.

Innovative therapeutics like biologicals that modulate the immune system are on the rise. However, their immune-modulating characteristics can also lead sometimes to the induction of adverse effects, by triggering unintended immune reactions. Due to the complexity and target-specificity of such therapeutics, these drug-induced adverse events could remain undetected during non-clinical development, if the test systems are, for example, animal-based, and only emerge in clinical development when tested in humans and subsequently lead to discontinuance of otherwise promising drug candidates. To identify adverse effects on the human immune system at an early stage, new approaches, assays, and technologies are needed. The Innovative Medicine Initiative (IMI) cooperation Immune Safety Avatar (imSAVAR) project aims to develop a tool for integrated non-clinical safety assessment for immune-modulatory new therapeutic drugs and clinical trial applications. To achieve this goal, imSAVAR has relied on the Adverse Outcome Pathway (AOP) framework to gather knowledge in a structured approach and to design, select or develop, when needed, appropriate test systems for prediction of the immune-related adverse outcomes. So far, the imSAVAR consortium has identified the "mode of action" for certain classes of drugs that needed improved risk assessment, including chimeric antigen receptor T cells (CAR T cells), immune checkpoint inhibitors (ICIs), and recombinant proteins (e.g. interleukin [IL]-2), has linked those to their immune-related adverse outcomes and has formulated literature-based immune-related AOPs (irAOPs). Models to measure those immune-specific perturbations were selected, adjusted, or newly developed. The imSAVAR work described in this special issue of The Journal of Immunotoxicology supports our understanding of immune-mediated adverse effects and their early discovery during development to improve the safety of innovative biomedicals.

Immune-related adverse outcome pathways (irAOPs) are a toxicological tool for the structuring of complex immunological mechanisms. The EU-funded IMI-project imSAVAR analyses the applicability of irAOPs in pre-clinical safety assessment of immunotherapies. Here, we use immunotherapy with interleukin (IL)-2 as a use case to develop an irAOP for IL-2-mediated vascular leakage (VL). Despite severe side effects observed upon high-dose treatment, IL-2 remains a promising candidate for cancer- and autoimmune therapy. The secondary systemic capillary leakage syndrome is described by a high mortality and a lethality rate of 20 - 30%. However, due to its non-specific symptoms, it remains a serious but under-diagnosed pathology. VL as general phenomenon is associated with several pro-inflammatory scenarios or observed as severe side effect of immunotherapies. In such situations, the physiological condition, in which endothelial cells (ECs) form the semipermeable seal of the vasculature, can escalate into pathological vascular permeability and finally VL. Although EC-biology and mechanisms underlying VL are ongoing subjects of research since many years, exact understanding of VL pathophysiology remains unclear. With this review, we provide an overview of the development of VL from an immunological perspective in the context of high-dose IL-2 immunotherapy. We structured the corresponding knowledge and generated an irAOP for IL-2-mediated VL with the aim to identify gaps and possible biomarkers. Gained insights from this theoretical approach facilitate the identification of relevant scientific questions as a basis for concrete experimental work. Integration of novel experiment-based knowledge into the existing irAOP could close a 'feedback-loop' by enabling irAOP-refinement and the identification of new questions. At the same time this could give rise to important information to improve test systems for IL-2-based immunotherapy safety-assessment and overall the approach to understand, prevent, or predict VL as critical side effect of other clinical conditions.

Interleukin-2 (IL-2) was one of the first cytokines discovered and its central role in T cell function soon led to the notion that the cytokine could specifically activate immune cells to combat cancer cells. Recombinant human IL-2 (recIL-2) belonged to the first anti-cancer immunotherapeutics that received marketing authorization and while it mediated anti-tumor effects in some cancer entities, treatment was associated with severe and systemic side effects. RecIL-2 holds an exceptional therapeutic potential, which can either lead to stimulation of the immune system - favorable during cancer treatment - or immunosuppression - used for treatment of inflammatory diseases such as autoimmunity. Due to these pleiotropic immune effects, recIL-2 therapy is still a hot topic in research and modified recIL-2 drug candidates show ameliorated efficacy and safety in pre-clinical and clinical studies. The Immune Safety Avatar (imSAVAR) consortium aims to systemically assess mechanisms leading to adverse events provoked by recIL-2 immunotherapy as a use case in order to aid safety evaluation of future recIL-2-based therapies. Here, we summarize the historical use of recIL-2 therapy, associated side effects, and describe the molecular basis of the dual role of IL-2. Finally, an overview of new recIL-2 compounds and delivery systems, which are currently being developed, will be given, highlighting a possible comeback of recIL-2 therapy.

CD19-targeted chimeric antigen receptor-modified T (CAR-T) cells have shown success in clinical studies, with several CD19 CAR-T cell products now having been approved for market use. However, this cell therapy can be associated with side effects such as cytokine release syndrome (CRS). Therefore, pre-clinical test systems are highly desired to permit the evaluation of these unwanted effects before clinical trials begin. In this study, we evaluated cytokine secretion and cell phenotype changes induced by human CD4⁺ and CD8⁺ CD19-targeted CAR-T cells in the cytokine release assay (CRA) module of a pre-clinical human in vitro 3D co-culture platform. The in vitro CRA data showed that CD19-targeted CAR-T cells induced a diverse and concentration-dependent cytokine response led by a T_H1-profile (IFNγ, IL-2) and pro-inflammatory cytokines (IL-6, TNFα, MCP-1, IL-8, MIP-1b). It was also shown that different cellular components in this 3D co-culture system contributed to the CAR-T cell cytokine response. In particular, whole blood-derived cell populations were necessary to drive the production of T cell cytokines, and endothelial cells were required to generate pro-inflammatory cytokines. CD19-targeted CAR-T cells also triggered cell phenotype changes, including the activation of whole blood-derived CD4⁺ and CD8⁺ T-cells and activation/maturation of antigen-presenting cells, during treatment of the in vitro CRA platform. Additionally, the observation of a CD19-targeted CAR-T cell concentration-dependent reduction in the B-cell compartment in this study is aligned with the expected pharmacology and clinical profile of this compound. Overall, this dataset shows the utility of an in vitro CRA model as a pre-clinical platform for evaluating cytokine release potential and analysis of mechanisms of action of CD19-targeted CAR-T cells.

The success of cellular immunotherapies such as chimeric antigen receptor (CAR) T cell therapy has led to their implementation as a revolutionary treatment option for cancer patients. However, the safe translation of such novel immunotherapies, from non-clinical assessment to first-in-human studies is still hampered by the lack of suitable in vitro and in vivo models recapitulating the complexity of the human immune system. Additionally, using cells derived from human healthy volunteers in such test systems may not adequately reflect the altered state of the patient's immune system thus potentially underestimating the risk of life-threatening conditions, such as cytokine release syndrome (CRS) following CAR T cell therapy. The IMI2/EU project imSAVAR (immune safety avatar: non-clinical mimicking of the immune system effects of immunomodulatory therapies) aims at creating a platform for novel tools and models for enhanced non-clinical prediction of possible adverse events associated with immunomodulatory therapies. This platform shall in the future guide early non-clinical safety assessment of novel immune therapeutics thereby also reducing the costs of their development. Therefore, we review current opportunities and challenges associated with non-clinical in vitro and in vivo models for the safety assessment of CAR T cell therapy ranging from organ-on-chip models up to advanced biomarker screening.

Novel immunotherapies for cancer and other diseases aim to trigger the immune system to produce durable responses, while overcoming the immunosuppression that may contribute to disease severity, and in parallel considering immunosafety aspects. Interleukin-2 (IL-2) was one of the first cytokines that the FDA approved as a cancer-targeting immunotherapy. However, in the past years, IL-2 immunotherapy is not actively offered to patients, due to limited efficacy, when compared to other novel immunotherapies, and the associated severe adverse events. In order to design improved in vitro and in vivo models, able to predict the efficacy and safety of novel IL-2 alternatives, it is important to delineate the mechanistic immunological events triggered by IL-2. Particularly, in this review we will discuss the effects IL-2 has with the bridging cell type of the innate and adaptive immune responses, dendritic cells. The pathways involved in the regulation of IL-2 by dendritic cells and T-cells in cancer and autoimmune disease will also be explored.