Quadruple co-culture vascular models of haematological malignancy CAR T cell therapy for nonclinical safety and efficacy studies

Chimeric Antigen Receptor T (CAR T) cell therapy is continually advancing in the immune-oncology field, with several treatments having been approved for haematological malignancies. As a rapidly growing and effective treatment option for a range of malignancies and patients with advanced stage cancer, there is now a focus on predicting, preventing and treating its associated side effects to optimise the clinical outcome. Cytokine Release Syndrome (CRS) is one such side effect that frequently occurs after CAR T cell therapy, which can be fatal in severe cases. Modelling the clinical response to CAR T cell therapy is therefore key to developing and administering the safest and most effective treatments. Given the poor translatability of animal models and the ethical considerations of this approach, advanced in vitro new approach methodologies (NAMs) are highly needed. Within imSAVAR (immune safety avatar), an IMI2/EU project focused on nonclinical mimicking of the immune system effects of immunomodulatory therapies, this work focused on developing human vascular models for studying the safety and efficacy of CD19-targeting CAR T cell therapies. Utilising autologous endothelial cells, peripheral blood mononuclear cells and CAR T cells, we demonstrate the ability of these vascular models to recapitulate selected features associated with clinical CAR T-cell responses in the presence of a target cancer cell line, such as cytokine release and functional cell killing. As a proof-of-concept study, this work establishes a complex in vitro model (CIVM) for use in future CAR T cell therapy development and potential wider applications.