An Immunocompetent Microphysiological System to Simultaneously Investigate Effects of Anti-Tumor Natural Killer Cells on Tumor and Cardiac Microtissues

Recapitulating the Cancer-Immunity Cycle on a Chip

The cancer-immunity cycle is a fundamental framework for understanding how the immune system interacts with cancer cells, balancing T cell recognition and elimination of tumors while avoiding autoimmune reactions. Despite advancements in immunotherapy, there remains a critical need to dissect each phase of the cycle, particularly the interactions among the tumor, vasculature, and immune system within the tumor microenvironment (TME). Innovative platforms such as organ-on-a-chip, organoids, and bioprinting within microphysiological systems (MPS) are increasingly utilized to enhance the understanding of these interactions. These systems meticulously replicate crucial aspects of the TME and immune responses, providing robust platforms to study cancer progression, immune evasion, and therapeutic interventions with greater physiological relevance. This review explores the latest advancements in MPS technologies for modeling various stages of the cancer-immune cycle, critically evaluating their applications and limitations in advancing the understanding of cancer-immune dynamics and guiding the development of next-generation immunotherapeutic strategies.

Understanding organotropism in cancer metastasis using microphysiological systems

Cancer metastasis, the leading cause of cancer-related deaths, remains a complex challenge in medical science. Stephen Paget's "seed and soil theory" introduced the concept of organotropism, suggesting that metastatic success depends on specific organ microenvironments. Understanding organotropism not only offers potential for curbing metastasis but also novel treatment strategies. Microphysiological systems (MPS), especially organ-on-a-chip models, have emerged as transformative tools in this quest. These systems, blending microfluidics, biology, and engineering, grant precise control over cell interactions within organ-specific microenvironments. MPS enable real-time monitoring, morphological analysis, and protein quantification, enhancing our comprehension of cancer dynamics, including tumor migration, vascularization, and pre-metastatic niches. In this review, we explore innovative applications of MPS in investigating cancer metastasis, particularly focusing on organotropism. This interdisciplinary approach converges the field of science, engineering, and medicine, thereby illuminating a path toward groundbreaking discoveries in cancer research.

Progress in developing microphysiological systems for biological product assessment

Microphysiological systems (MPS), also known as miniaturized physiological environments, have been engineered to create and study functional tissue units capable of replicating organ-level responses in specific contexts. The MPS has the potential to provide insights about the safety, characterization, and effectiveness of medical products that are different and complementary to insights gained from traditional testing systems, which can help facilitate the transition of potential medical products from preclinical phases to clinical trials, and eventually to market. While many MPS are versatile and can be used in various applications, most of the current applications have primarily focused on drug discovery and testing. Yet, there is a limited amount of research available that demonstrates the use of MPS in assessing biological products such as cellular and gene therapies. This review paper aims to address this gap by discussing recent technical advancements in MPS and their potential for assessing biological products. We further discuss the challenges and considerations involved in successful translation of MPS into mainstream product testing.

Evaluation of stimbiotic on growth performance and intestinal development of broilers fed corn- or wheat-based diets

In the antibiotics-free era, stimbiotic (STB) has been suggested as a new alternative of antibiotic growth promoters to modulate intestinal health via stimulating dietary fiber utilization in poultry production. The aim of this study was to evaluate the effects of STB supplementation in corn- or wheat-basal diet on growth performance, intestinal development, and function of broilers. A total of 512 one-day-old Arbor Acres(AA)broilers were randomly allocated 4 treatments, including corn group (CG), corn + 100 g/t STB (CG + STB), wheat group (WG), wheat + 100 g/t STB (WG + STB). The broilers were weighed at the days of 14, 28, and 42, of which 8 repetitions per treatment were randomly selected to determine the intestinal morphology, intestinal barrier, and cecal microbiota and metabolites. Our data showed that STB increased (P < 0.05) feed intake, body weight and reduced FCR for the overall period (0-42 d). At 28 d of age, significant increases in villus height and the villus height-to-crypt depth ratio (V/C) were found in the STB supplementation groups (P < 0.05). Addition of STB significantly increased intestinal mucosal DAO and AMPK enzyme activity and the gene expression of OCLN, CLDN1, ZO1, MUC2, SGLT1, PEPT1, FABP2, Ghrelin, and GCG in jejunum (P < 0.05), and significantly decreased the expression of the PYY gene. In addition, STB increased the relative abundance of beneficial bacteria, such as Akkermansia, Bifidobacterium, and Oscillospirales (P < 0.05). A significant increase in cecal short-chain fatty acid (SCFAs) concentration was also observed in the STB supplementation groups. At the cellular level, STB cannot directly increase the expression of small intestinal epithelial cells, and may indirectly improve intestinal barrier function by increasing the level of sodium butyrate. Overall, these results indicated that STB supplementation could improve the growth performance, intestinal development and barrier functions, and fiber fermentation in cecum of broiler chickens.

Microphysiological systems as reliable drug discovery and evaluation tools: Evolution from innovation to maturity

Microphysiological systems (MPSs), also known as organ-on-chip or disease-on-chip, have recently emerged to reconstitute the in vivo cellular microenvironment of various organs and diseases on in vitro platforms. These microfluidics-based platforms are developed to provide reliable drug discovery and regulatory evaluation testbeds. Despite recent emergences and advances of various MPS platforms, their adoption of drug discovery and evaluation processes still lags. This delay is mainly due to a lack of rigorous standards with reproducibility and reliability, and practical difficulties to be adopted in pharmaceutical research and industry settings. This review discusses the current and potential use of MPS platforms in drug discovery processes while considering the context of several key steps during drug discovery processes, including target identification and validation, preclinical evaluation, and clinical trials. Opportunities and challenges are also discussed for the broader dissemination and adoption of MPSs in various drug discovery and regulatory evaluation steps. Addressing these challenges will transform long and expensive drug discovery and evaluation processes into more efficient discovery, screening, and approval of innovative drugs.

Organ-on-a-chip models for development of cancer immunotherapies

Cancer immunotherapy has emerged as a promising approach in the treatment of diverse cancer types. However, the development of novel immunotherapeutic agents faces persistent challenges due to poor translation from preclinical to clinical stages. To address these challenges, the integration of microfluidic models in research efforts has recently gained traction, bridging the gap between in vitro and in vivo systems. This approach enables modeling of the complex human tumor microenvironment and interrogation of cancer-immune interactions. In this review, we analyze the current and potential applications of microfluidic tumor models in cancer immunotherapy development. We will first highlight current trends in the immunooncology landscape. Subsequently, we will discuss recent examples of microfluidic models applied to investigate mechanisms of immune-cancer interactions and for developing and screening cancer immunotherapies in vitro. First steps toward their validation for predicting human in vivo outcomes are discussed. Finally, promising opportunities that microfluidic tumor models offer are highlighted considering their advantages and current limitations, and we suggest possible next steps toward their implementation and integration into the immunooncology drug development process.

Modeling immunity in microphysiological systems

There is a need for better predictive models of the human immune system to evaluate safety and efficacy of immunomodulatory drugs and biologics for successful product development and regulatory approvals. Current in vitro models, which are often tested in two-dimensional (2D) tissue culture polystyrene, and preclinical animal models fail to fully recapitulate the function and physiology of the human immune system. Microphysiological systems (MPSs) that can model key microenvironment cues of the human immune system, as well as of specific organs and tissues, may be able to recapitulate specific features of the in vivo inflammatory response. This minireview provides an overview of MPS for modeling lymphatic tissues, immunity at tissue interfaces, inflammatory diseases, and the inflammatory tumor microenvironment in vitro and ex vivo. Broadly, these systems have utility in modeling how certain immunotherapies function in vivo, how dysfunctional immune responses can propagate diseases, and how our immune system can combat pathogens.

In vitro models to study natural killer cell dynamics in the tumor microenvironment

Immunotherapy is revolutionizing cancer therapy. The rapid development of new immunotherapeutic strategies to treat solid tumors is posing new challenges for preclinical research, demanding novel in vitro methods to test treatments. Such methods should meet specific requirements, such as enabling the evaluation of immune cell responses like cytotoxicity or cytokine release, and infiltration into the tumor microenvironment using cancer models representative of the original disease. They should allow high-throughput and high-content analysis, to evaluate the efficacy of treatments and understand immune-evasion processes to facilitate development of new therapeutic targets. Ideally, they should be suitable for personalized immunotherapy testing, providing information for patient stratification. Consequently, the application of in vitro 3-dimensional (3D) cell culture models, such as tumor spheroids and organoids, is rapidly expanding in the immunotherapeutic field, coupled with the development of novel imaging-based techniques and -omic analysis. In this paper, we review the recent advances in the development of in vitro 3D platforms applied to natural killer (NK) cell-based cancer immunotherapy studies, highlighting the benefits and limitations of the current methods, and discuss new concepts and future directions of the field.

Recent progress in nanocarrier-based drug delivery systems for antitumour metastasis

Tumour metastasis is one of the major factors leading to poor prognosis as well as lower survival among cancer patients. A number of studies investigating the inhibition of tumour metastasis have been conducted. It is difficult to achieve satisfactory results with surgery alone for distant metastatic tumours, and chemotherapy can boost the healing rate and prognosis of patients. However, the poor therapeutic efficacy of chemotherapy drugs due to their low solubility, lack of tumour targeting, instability in vivo, high toxicity and multidrug resistance hinder their application. Immunotherapy is beneficial to the treatment of metastatic cancers, but it also has disadvantages such as adverse reactions and acquired resistance. Fortunately, delivery of chemotherapeutic drugs with nanocarriers can reduce systemic reactions caused by chemotherapeutic agents and inhibit metastasis. This review discusses the underlying mechanisms of metastasis, therapeutic approaches for antitumour metastasis, the advantages of nanodrug delivery systems and their application in reducing metastasis.

Recent advances in microfluidic-based cancer immunotherapy-on-a-chip strategies

Despite several extraordinary improvements in cancer immunotherapy, its therapeutic effectiveness against many distinct cancer types remains mostly limited and requires further study. Different microfluidic-based cancer immunotherapy-on-a-chip (ITOC) systems have been developed to help researchers replicate the tumor microenvironment and immune system. Numerous microfluidic platforms can potentially be used to perform various on-chip activities related to early clinical cancer immunotherapy processes, such as improving immune checkpoint blockade therapy, studying immune cell dynamics, evaluating cytotoxicity, and creating vaccines or organoid models from patient samples. In this review, we summarize the most recent advancements in the development of various microfluidic-based ITOC devices for cancer treatment niches and present future perspectives on microfluidic devices for immunotherapy research.

Engineered Microphysiological Systems for Testing Effectiveness of Cell-Based Cancer Immunotherapies

Cell therapies, including adoptive immune cell therapies and genetically engineered chimeric antigen receptor (CAR) T or NK cells, have shown promise in treating hematologic malignancies. Yet, immune cell infiltration and expansion has proven challenging in solid tumors due to immune cell exclusion and exhaustion and the presence of vascular barriers. Testing next-generation immune therapies remains challenging in animals, motivating sophisticated ex vivo models of human tumor biology and prognostic assays to predict treatment response in real-time while comprehensively recapitulating the human tumor immune microenvironment (TIME). This review examines current strategies for testing cell-based cancer immunotherapies using ex vivo microphysiological systems and microfluidic technologies. Insights into the multicellular interactions of the TIME will identify novel therapeutic strategies to help patients whose tumors are refractory or resistant to current immunotherapies. Altogether, these microphysiological systems (MPS) have the capability to predict therapeutic vulnerabilities and biological barriers while studying immune cell infiltration and killing in a more physiologically relevant context, thereby providing important insights into fundamental biologic mechanisms to expand our understanding of and treatments for currently incurable malignancies.

3D in vitro Models of Pathological Skeletal Muscle: Which Cells and Scaffolds to Elect?

Skeletal muscle is a fundamental tissue of the human body with great plasticity and adaptation to diseases and injuries. Recreating this tissue in vitro helps not only to deepen its functionality, but also to simulate pathophysiological processes. In this review we discuss the generation of human skeletal muscle three-dimensional (3D) models obtained through tissue engineering approaches. First, we present an overview of the most severe myopathies and the two key players involved: the variety of cells composing skeletal muscle tissue and the different components of its extracellular matrix. Then, we discuss the peculiar characteristics among diverse in vitro models with a specific focus on cell sources, scaffold composition and formulations, and fabrication techniques. To conclude, we highlight the efficacy of 3D models in mimicking patient-specific myopathies, deepening muscle disease mechanisms or investigating possible therapeutic effects.

Evaluating immune response in vitro in a relevant microenvironment: a high-throughput microfluidic model for clinical screening

Aim

Functional screening of new pharmaceutical compounds requires clinically relevant models to monitor essential cellular and immune responses during cancer progression, with or without treatment. Beyond survival, the emergence of resistant tumor cell clones should also be considered, including specific properties related to plasticity, such as invasiveness, stemness, escape from programmed cell death, and immune response. Numerous pathways are involved in these processes. Defining the relevant ones in the context of a specific tumor type will be key to designing an appropriate combination of inhibitors. However, the diversity and potential redundancy of these pathways remain a challenge for therapy.

Methods

A new microfluidic device developed by Okomera was dedicated to the screening of drug treatment for breast cancer. This microchip includes 150 droplet-trapping microwells, offering multi-chip settings and multiple treatment choices.

Results

After validating the system with established cell lines and a panel of drugs used clinically at Gustave Roussy, preclinical experiments were initiated including patient-derived xenograft (PDX) and primary tumor cells-derived tumoroids with the collaboration of Gustave Roussy clinicians. Tumor-isolated lymphocytes were also added to the tumoroids, using secondary droplets in proof-of-concept experiments.

Conclusions

These results show the relevance of the methodology for screening large numbers of drugs, a wide range of doses, and multiple drug combinations. This methodology will be used for two purposes: 1) new drug screening from the compound library, using the high throughput potential of the chip; and 2) pre-clinical assay for a two-weeks response for personalized medicine, allowing evaluation of drug combinations to flag an optimized treatment with potential clinical application.