Industrializing Autologous Adoptive Immunotherapies: Manufacturing Advances and Challenges

Transduction enhancing EF-C peptide nanofibrils are endocytosed by macropinocytosis and subsequently degraded

Retroviral gene transfer is the preferred method for stable, long-term integration of genetic material into cellular genomes, commonly used to generate chimeric antigen receptor (CAR)-T cells designed to target tumor antigens. However, the efficiency of retroviral gene transfer is often limited by low transduction rates due to low vector titers and electrostatic repulsion between viral particles and cellular membranes. To overcome these limitations, peptide nanofibrils (PNFs) can be applied as transduction enhancers. Among these, PNFs derived from the 12-mer peptide EF-C are well-investigated and commercially available. EF-C PNFs enhance transduction by forming EF-C PNFs/virus complexes that overcome electrostatic repulsion through their polycationic surface and interaction with cellular protrusions. However, the safe application of PNFs as transduction enhancers in gene therapeutic applications requires a fundamental understanding of their transduction-enhancing mechanisms, uptake, and degradation. In this study, we demonstrate that EF-C PNFs induce plasma membrane invaginations, increasing the membrane surface for viral attachment and reducing the distance to the nuclear membrane, thereby facilitating viral entry and transport to the nucleus. Furthermore, we identified macropinocytosis as the main entry pathway for EF-C PNFs and their subsequent degradation by lysosomal peptidases. The lysosomal degradation of EF-C PNFs prevents their accumulation as amyloid deposits, mitigating potential side effects and supporting their safe use in clinical applications.

The advent of chimeric antigen receptor T Cell therapy in recalibrating immune balance for rheumatic autoimmune disease treatment

CAR-T cell therapy, a cutting-edge cellular immunotherapy with demonstrated efficacy in treating hematologic malignancies, also exhibits significant promise for addressing autoimmune diseases. This innovative therapeutic approach holds promise for achieving long-term remission in autoimmune diseases, potentially offering significant benefits to affected patients. Current targets under investigation for the treatment of these conditions include CD19, CD20, and BCMA, among others. However, CAR-T therapy faces difficulties such as time-consuming cell manufacturing, complex and expensive process, and the possibility of severe adverse reactions complicating the treatment, etc. This article examines CAR-T therapy across various rheumatic autoimmune diseases, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjögren's syndrome (SS), systemic sclerosis (SSc), antisynthetase syndrome (ASS), and ANCA-associated vasculitis (AAV), highlighting both therapeutic advancements and ongoing challenges.

Cryopreservation of Immune Cells: Recent Progress and Challenges Ahead

Cryopreservation of immune cells is considered as a key enabling technology for adoptive cellular immunotherapy. However, current immune cell cryopreservation technologies face the challenges with poor biocompatibility of cryoprotection materials, low efficiency, and impaired post-thaw function, limiting their clinical translation. This review briefly introduces the adoptive cellular immunotherapy and the approved immune cell-based products, which involve T cells, natural killer cells and etc. The cryodamage mechanisms to these immune cells during cryopreservation process are described, including ice formation related mechanical and osmotic injuries, cryoprotectant induced toxic injuries, and other biochemical injuries. Meanwhile, the recent advances in the cryopreservation medium and freeze-thaw protocol for several representative immune cell type are summarized. Furthermore, the remaining challenges regarding on the cryoprotection materials, freeze-thaw protocol, and post-thaw functionality evaluation of current cryopreservation technologies are discussed. Finally, the future perspectives are proposed toward advancing highly efficient cryopreservation of immune cells.

A high-density microfluidic bioreactor for the automated manufacturing of CAR T cells

The manufacturing of autologous chimaeric antigen receptor (CAR) T cells largely relies either on fed-batch and manual processes that often lack environmental monitoring and control or on bioreactors that cannot be easily scaled out to meet patient demands. Here we show that human primary T cells can be activated, transduced and expanded to high densities in a 2 ml automated closed-system microfluidic bioreactor to produce viable anti-CD19 CAR T cells (specifically, more than 60 million CAR T cells from donor cells derived from patients with lymphoma and more than 200 million CAR T cells from healthy donors). The in vitro secretion of cytokines, the short-term cytotoxic activity and the long-term persistence and proliferation of the cell products, as well as their in vivo anti-leukaemic activity, were comparable to those of T cells produced in a gas-permeable well. The manufacturing-process intensification enabled by the miniaturized perfusable bioreactor may facilitate the analysis of the growth and metabolic states of CAR T cells during ex vivo culture, the high-throughput optimization of cell-manufacturing processes and the scale out of cell-therapy manufacturing.

CAR assembly line: Taking CAR T-cell manufacturing to the next level

The widespread adoption of chimeric antigen receptor (CAR) T-cell therapy has been limited by complex, resource-intensive manufacturing processes. This review discusses the latest innovations aiming to improve and streamline CAR T-cell production across key steps like T-cell activation, genetic modification, expansion, and scaling. Promising techniques highlighted include generating CAR T cells from non-activated lymphocytes to retain a stem-like phenotype and function, non-viral gene transfer leveraging platforms like transposon and CRISPR, all-in-one fully automated bioreactors like the CliniMACS Prodigy and the Lonza Cocoon, rapid CAR T-cell manufacturing via abbreviating or eliminating ex vivo T-cell culture, implementing decentralized point-of-care automated manufacturing platforms, and optimizing centralized bioreactor infrastructure integrating end-to-end automation. Adoption of these emerging technologies can reduce production costs and timelines while enhancing product quality and accessibility. However, significant knowledge gaps persist regarding the feasibility, superiority, and optimal protocols for effectively incorporating many emerging techniques into widespread clinical practice. Further validation through clinical studies is still needed for many of these novel approaches.

Automation preserves product consistency and quality for the formulation, fill, and finish of T cell-based therapies

Scaling up the manufacture of cell therapies can be complex and challenging. Maintaining critical quality attributes of the cell product during its final formulation and fill-finish into multiple containers can be especially difficult and laborious. Here, we tested the automated Finia™ Fill and Finish System to efficiently scale up the formulation and fill-finish of a T cell product, and then assessed cell quality and product consistency across different sub-lots filled during this expanded process. We found that this automated system could be effectively scaled to 4 times its singular capacity in a 2-h time interval, with variation in cell number and product volume less than 12% across all containers. Analysis of the different sub-lots of the final product revealed high cell viability and consistent T cell phenotype, with a high proportion of effector memory and central memory T cells and low expression of T cell senescence and exhaustion markers. The functionality of the T cell product was compared by measuring cytokine response after restimulation, with secreted levels of effector cytokines like IFN-γ and TNF-α being similar across the different sub-lots. Collectively, these results show that automation can scale up the formulation and fill-finish of a cell manufacturing process while maintaining the phenotype and functionality of the cell product. Better understanding of how to maintain product uniformity and quality during final manufacturing is important to the further scale-up and development of successful cell therapies.

Retrovirus-based manufacturing of chimeric antigen receptor-modified T cells for cancer therapy research

Treatment with autologous chimeric antigen receptor (CAR)-modified T cells can achieve outstanding clinical response rates in heavily pretreated patients with B and plasma cell malignancies. However, relapses occur, and they limit the efficacy of this promising treatment approach. The complex GMP-compliant production and high treatment costs cause that CAR T cells cannot yet be used in a broad population. Among others, CAR T cell therapy has evolved regarding vector design and manufacturing process. Optimal production of CAR T cells is not yet defined, far from being standardized. Quality, cellular composition and immunophenotype of the administered CAR T cells are influenced by the manufacturing protocol and therefore play a crucial role for therapeutic success. For the gene transfer, viral and non-viral strategies are available. Retrovirus-based protocols for CAR T cell production offer advantages in terms of stable gene integration, sufficient transduction efficiency, proven clinical success, and scalability. Here, we detail a retrovirus-based generation protocol of human CAR-modified T cells for experimental immunotherapeutic treatment of cancer cells. For the CAR generation, HEK-293-based packaging cell lines, CD3+ selection, CD3/CD28-coated bead-based activation and IL-2/IL-15-mediated expansion were used. This protocol can be applied for every possible CAR construct after being successfully transfected in HEK-293-based packaging cell lines.

Enrichment of T-lymphocytes from leukemic blood using inertial microfluidics toward improved chimeric antigen receptor-T cell manufacturing

Chimeric antigen receptor cell therapy is a successful immunotherapy for the treatment of blood cancers. However, hurdles in their manufacturing remain including efficient isolation and purification of the T-cell starting material. Herein, we describe a one-step separation based on inertial spiral microfluidics for efficient enrichment of T-cells in B-cell acute lymphoblastic leukemia (ALL) and B-cell chronic lymphocytic leukemia patient's samples. In healthy donors used to optimize the process, the lymphocyte purity was enriched from 65% (SD ± 0.2) to 91% (SD ± 0.06) and T-cell purity was enriched from 45% (SD ± 0.1) to 73% (SD ± 0.02). Leukemic samples had higher starting B-cells compared to the healthy donor samples. Efficient enrichment and recovery of lymphocytes and T-cells were achieved in ALL samples with B-cells, monocytes and leukemic blasts depleted by 80% (SD ± 0.09), 89% (SD ± 0.1) and 74% (SD ± 0.09), respectively, and a 70% (SD ± 0.1) T-cell recovery. Chronic lymphocytic leukemia samples had lower T-cell numbers, and the separation process was less efficient compared to the ALL. This study demonstrates the use of inertial microfluidics for T-cell enrichment and depletion of B-cell blasts in ALL, suggesting its potential to address a key bottleneck of the chimeric antigen receptor-T manufacturing workflow.

An integrated perspective on measuring cytokines to inform CAR-T bioprocessing

Chimeric antigen receptor (CAR)-T cells are emerging as a generation-defining therapeutic however their manufacture remains a major barrier to meeting increased market demand. Monitoring critical quality attributes (CQAs) and critical process parameters (CPPs) during manufacture would vastly enrich acquired information related to the process and product, providing feedback to enable real-time decision making. Here we identify specific CAR-T cytokines as value-adding analytes and discuss their roles as plausible CPPs and CQAs. High sensitivity sensing technologies which can be easily integrated into manufacture workflows are essential to implement real-time monitoring of these cytokines. We therefore present biosensors as enabling technologies and evaluate recent advancements in cytokine detection in cell cultures, offering promising translatability to CAR-T biomanufacture. Finally, we outline emerging sensing technologies with future promise, and provide an overall outlook on existing gaps to implementation and the optimal sensing platform to enable cytokine monitoring in CAR-T biomanufacture.

Materials for Cell Surface Engineering

Cell therapies are emerging as a promising new therapeutic modality in medicine, generating effective treatments for previously incurable diseases. Clinical success of cell therapies has energized the field of cellular engineering, spurring further exploration of novel approaches to improve their therapeutic performance. Engineering of cell surfaces using natural and synthetic materials has emerged as a valuable tool in this endeavor. This review summarizes recent advances in the development of technologies for decorating cell surfaces with various materials including nanoparticles, microparticles, and polymeric coatings, focusing on the ways in which surface decorations enhance carrier cells and therapeutic effects. Key benefits of surface-modified cells include protecting the carrier cell, reducing particle clearance, enhancing cell trafficking, masking cell-surface antigens, modulating inflammatory phenotype of carrier cells, and delivering therapeutic agents to target tissues. While most of these technologies are still in the proof-of-concept stage, the promising therapeutic efficacy of these constructs from in vitro and in vivo preclinical studies has laid a strong foundation for eventual clinical translation. Cell surface engineering with materials can imbue a diverse range of advantages for cell therapy, creating opportunities for innovative functionalities, for improved therapeutic efficacy, and transforming the fundamental and translational landscape of cell therapies.

3D Printing as a Strategy to Scale-Up Biohybrid Hydrogels for T Cell Manufacture

The emergence of cellular immunotherapy treatments is introducing more efficient strategies to combat cancer as well as autoimmune and infectious diseases. However, the cellular manufacturing procedures associated with these therapies remain costly and time-consuming, thus limiting their applicability. Recently, lymph-node-inspired PEG-heparin hydrogels have been demonstrated to improve primary human T cell culture at the laboratory scale. To go one step further in their clinical applicability, we assessed their scalability, which was successfully achieved by 3D printing. Thus, we were able to improve primary human T cell infiltration in the biohybrid PEG-heparin hydrogels, as well as increase nutrient, waste, and gas transport, resulting in higher primary human T cell proliferation rates while maintaining the phenotype. Thus, we moved one step further toward meeting the requirements needed to improve the manufacture of the cellular products used in cellular immunotherapies.

Cancer Nanovaccines: Nanomaterials and Clinical Perspectives

Cancer nanovaccines represent a promising frontier in cancer immunotherapy, utilizing nanotechnology to augment traditional vaccine efficacy. This review comprehensively examines the current state-of-the-art in cancer nanovaccine development, elucidating innovative strategies and technologies employed in their design. It explores both preclinical and clinical advancements, emphasizing key studies demonstrating their potential to elicit robust anti-tumor immune responses. The study encompasses various facets, including integrating biomaterial-based nanocarriers for antigen delivery, adjuvant selection, and the impact of nanoscale properties on vaccine performance. Detailed insights into the complex interplay between the tumor microenvironment and nanovaccine responses are provided, highlighting challenges and opportunities in optimizing therapeutic outcomes. Additionally, the study presents a thorough analysis of ongoing clinical trials, presenting a snapshot of the current clinical landscape. By curating the latest scientific findings and clinical developments, this study aims to serve as a comprehensive resource for researchers and clinicians engaged in advancing cancer immunotherapy. Integrating nanotechnology into vaccine design holds immense promise for revolutionizing cancer treatment paradigms, and this review provides a timely update on the evolving landscape of cancer nanovaccines.

Stain-Free Approach to Determine and Monitor Cell Heath Using Supervised and Unsupervised Image-Based Deep Learning

Cell-based medicinal products (CBMPs) are a growing class of therapeutics that promise new treatments for complex and rare diseases. Given the inherent complexity of the whole human cells comprising CBMPs, there is a need for robust and fast analytical methods for characterization, process monitoring, and quality control (QC) testing during their manufacture. Existing techniques to evaluate and monitor cell quality typically constitute labor-intensive, expensive, and highly specific staining assays. In this work, we combine image-based deep learning with flow imaging microscopy (FIM) to predict cell health metrics using cellular morphology "fingerprints" extracted from images of unstained Jurkat cells (immortalized human T-lymphocyte cells). A supervised (i.e., algorithm trained with human-generated labels for images) fingerprinting algorithm, trained on images of unstained healthy and dead cells, provides a robust stain-free, non-invasive, and non-destructive method for determining cell viability. Results from the stain-free method are in good agreement with traditional stain-based cytometric viability measurements. Additionally, when trained with images of healthy cells, dead cells and cells undergoing chemically induced apoptosis, the supervised fingerprinting algorithm is able to distinguish between the three cell states, and the results are independent of specific treatments or signaling pathways. We then show that an unsupervised variational autoencoder (VAE) algorithm trained on the same images, but without human-generated labels, is able to distinguish between samples of healthy, dead and apoptotic cells along with cellular debris based on learned morphological features and without human input. With this, we demonstrate that VAEs are a powerful exploratory technique that can be used as a process monitoring analytical tool.

Piloting a scale-up platform for high-quality human T-cells production

Cell and gene therapies are an innovative solution to various severe diseases and unfulfilled needs. Adoptive cell therapy (ACT), a form of cellular immunotherapies, has been favored in recent years due to the approval of chimeric antigen receptor CAR-T products. Market research indicates that the industry's value is predicted to reach USD 24.4 billion by 2030, with a compound annual growth rate (CAGR) of 21.5%. More importantly, ACT is recognized as the hope and future of effective, personalized cancer treatment for healthcare practitioners and patients worldwide. The significant global momentum of this therapeutic approach underscores the urgent need to establish it as a practical and standardized method. It is essential to understand how cell culture conditions affect the expansion and differentiation of T-cells. However, there are ongoing challenges in ensuring the robustness and reproducibility of the manufacturing process. The current study evaluated various adoptive T-cell culture platforms to achieve large-scale production of several billion cells and high-quality cellular output with minimal cell death. It examined factors such as bioreactor parameters, media, supplements and stimulation. This research addresses the fundamental challenges of scalability and reproducibility in manufacturing, which are essential for making adoptive T-cell therapy an accessible and powerful new class of cancer therapeutics.

Progress on Electro-Enhancement of Cell Manufacturing

With the long persistence of complex, chronic diseases in society, there is increasing motivation to develop cells as living medicine to treat diseases ranging from cancer to wounds. While cell therapies can significantly impact healthcare, the shortage of starter cells meant that considerable raw materials must be channeled solely for cell expansion, leading to expensive products with long manufacturing time which can prevent accessibility by patients who either cannot afford the treatment or have highly aggressive diseases and cannot wait that long. Over the last three decades, there has been increasing knowledge on the effects of electrical modulation on proliferation, but to the best of the knowledge, none of these studies went beyond how electro-control of cell proliferation may be extended to enhance industrial scale cell manufacturing. Here, this review is started by discussing the importance of maximizing cell yield during manufacturing before comparing strategies spanning biomolecular/chemical/physical to modulate cell proliferation. Next, the authors describe how factors governing invasive and non-invasive electrical stimulation (ES) including capacitive coupling electric field may be modified to boost cell manufacturing. This review concludes by describing what needs to be urgently performed to bridge the gap between academic investigation of ES to industrial applications.

On-chip flow cytometer using integrated photonics for the detection of human leukocytes

Differentiation between leukocyte subtypes like monocytes and lymphocytes is essential for cell therapy and research applications. To guarantee the cost-effective delivery of functional cells in cell therapies, billions of cells must be processed in a limited time. Yet, the sorting rates of commercial cell sorters are not high enough to reach the required yield. Process parallelization by using multiple instruments increases variability and production cost. A compact solution with higher throughput can be provided by multichannel flow cytometers combining fluidics and optics on-chip. In this work, we present a micro-flow cytometer with monolithically integrated photonics and fluidics and demonstrate that both the illumination of cells, as well as the collection of scattered light, can be realized using photonic integrated circuits. Our device is the first with sufficient resolution for the discrimination of lymphocytes and monocytes. Innovations in microfabrication have enabled complete integration of miniaturized photonic components and fluidics in a CMOS-compatible wafer stack. In combination with external optics, the device is ready for the collection of fluorescence using the on-chip excitation.

Implementation of mDoE-methods to a microcarrier-based expansion processes for mesenchymal stem cells

The need for advanced therapy medicinal products (ATMPs) has gained increased attention in recent years. In this respect, a well-designed cell expansion process is needed to efficiently manufacture the required number of cells with the desired product quality. This step is challenging due to the biological complexity of the respective primary cell (e.g., mesenchymal stem cells (MSC)) and the usage of microcarrier-based expansion systems. One accelerating approach for process design is model-assisted Design of Experiments (mDoE) combining mathematical process models and statistical tools. In this study, the mDoE workflow was used for the development of an expansion processes with human immortalized mesenchymal stem cells (hMSC-TERT) and the aim of maximizing cell yield assuming only a limited amount of prior knowledge at a very early stage of development. First, suitable microcarriers for expansion in shake flasks were screened and the differentiation of the cells was proven. Second, initial experiments were performed to generate prior knowledge, which was then used to set up the mathematical model and to estimate the model parameters. Finally, the mDoE was used to determine and evaluate the design space to be performed experimentally. Overall, a cell expansion process using microcarriers in a shake flask culture was successfully implemented and a significant increase in cell yield (up to 6,2-fold) was achieved compared to literature.

CD155 as an emerging target in tumor immunotherapy

CD155 is an immunoglobulin-like protein overexpressed in almost all the tumor cells, which not only promotes proliferation, adhesion, invasion, and migration of tumor cells, but also regulates immune responses by interacting with TIGIT, CD226 or CD96 receptors expressed on several immune cells, thereby modulating the functionality of these cellular subsets. As a novel immune checkpoint, the inhibition of CD155/TIGIT, either as a standalone treatment or in conjunction with other immune checkpoint inhibitors, has demonstrated efficacy in managing advanced solid malignancies. In this review, we summarize the intricate relationship between on tumor surface CD155 and its receptors, with further discussion on how they regulate the occurrence of tumor immune escape. In addition, novel therapeutic strategies and clinical trials targeting CD155 and its receptors are summarized, providing a strong rationale and way forward for the development of next-generation immunotherapies.

CAR-NK cells in combination therapy against cancer: A potential paradigm

Various preclinical and a limited number of clinical studies of CAR-NK cells have shown promising results: efficient elimination of target cells without side effects similar to CAR-T therapy. However, the homing and infiltration abilities of CAR-NK cells are poor due to the inhibitory tumor microenvironment. From the perspective of clinical treatment strategies, combined with the biological and tumor microenvironment characteristics of NK cells, CAR-NK combination therapy strategies with anti-PD-1/PD-L1, radiotherapy and chemotherapy, kinase inhibitors, proteasome inhibitors, STING agonist, oncolytic virus, photothermal therapy, can greatly promote the proliferation, migration and cytotoxicity of the NK cells. In this review, we will summarize the targets selection, structure constructions and combinational therapies of CAR-NK cells for tumors to provide feasible combination strategies for overcoming the inhibitory tumor microenvironment and improving the efficacy of CAR-NK cells.

Characterization of CAR T Cells Manufactured Using Genetically Engineered Artificial Antigen Presenting Cells

OBJECTIVE

Chimeric antigen receptor (CAR) T cell therapy has recently emerged as a promising approach for the treatment of different types of cancer. Improving CAR T cell manufacturing in terms of costs and product quality is an important concern for expanding the accessibility of this therapy. One proposed strategy for improving T cell expansion is to use genetically engineered artificial antigen presenting cells (aAPC) expressing a membrane-bound anti-CD3 for T cell activation. The aim of this study was to characterize CAR T cells generated using this aAPC-mediated approach in terms of expansion efficiency, immunophenotype, and cytotoxicity.

MATERIALS AND METHODS

In this experimental study, we generated an aAPC line by engineering K562 cells to express a membrane-bound anti-CD3 (mOKT3). T cell activation was performed by co-culturing PBMCs with either mitomycin C-treated aAPCs or surface-immobilized anti-CD3 and anti-CD28 antibodies. Untransduced and CD19-CARtransduced T cells were characterized in terms of expansion, activation markers, interferon gamma (IFN-γ) secretion, CD4/CD8 ratio, memory phenotype, and exhaustion markers. Cytotoxicity of CD19-CAR T cells generated by aAPCs and antibodies were also investigated using a bioluminescence-based co-culture assay.

RESULTS

Our findings showed that the engineered aAPC line has the potential to expand CAR T cells similar to that using the antibody-based method. Although activation with aAPCs leads to a higher ratio of CD8+ and effector memory T cells in the final product, we did not observe a significant difference in IFN-γ secretion, cytotoxic activity or exhaustion between CAR T cells generated with aAPC or antibodies.

CONCLUSION

Our results show that despite the differences in the immunophenotypes of aAPC and antibody-based CAR T cells, both methods can be used to manufacture potent CAR T cells. These findings are instrumental for the improvement of the CAR T cell manufacturing process and future applications of aAPC-mediated expansion of CAR T cells.

Elaborating the potential of Artificial Intelligence in automated CAR-T cell manufacturing

This paper discusses the challenges of producing CAR-T cells for cancer treatment and the potential for Artificial Intelligence (AI) for its improvement. CAR-T cell therapy was approved in 2018 as the first Advanced Therapy Medicinal Product (ATMP) for treating acute leukemia and lymphoma. ATMPs are cell- and gene-based therapies that show great promise for treating various cancers and hereditary diseases. While some new ATMPs have been approved, ongoing clinical trials are expected to lead to the approval of many more. However, the production of CAR-T cells presents a significant challenge due to the high costs associated with the manufacturing process, making the therapy very expensive (approx. $400,000). Furthermore, autologous CAR-T therapy is limited to a make-to-order approach, which makes scaling economical production difficult. First attempts are being made to automate this multi-step manufacturing process, which will not only directly reduce the high manufacturing costs but will also enable comprehensive data collection. AI technologies have the ability to analyze this data and convert it into knowledge and insights. In order to exploit these opportunities, this paper analyses the data potential in the automated CAR-T production process and creates a mapping to the capabilities of AI applications. The paper explores the possible use of AI in analyzing the data generated during the automated process and its capabilities to further improve the efficiency and cost-effectiveness of CAR-T cell production.

Effectiveness of radiotherapy and targeted radionuclide therapy for melanoma in preclinical mouse models: A combination treatments overview

Cutaneous melanoma is an aggressive and highly metastatic skin cancer. In recent years, immunotherapy and targeted small-molecule inhibitors have improved the overall survival of patients. Unfortunately, most patients in advanced stages of disease exhibit either intrinsically resistant or rapidly acquire resistance to these approved treatments. However, combination treatments have emerged to overcome resistance, and novel treatments based on radiotherapy (RT) and targeted radionuclide therapy (TRT) have been developed to treat melanoma in the preclinical mouse model, raising the question of whether synergy in combination therapies may motivate and increase their use as primary treatments for melanoma. To help clarify this question, we reviewed the studies in preclinical mouse models where they evaluated RT and TRT in combination with other approved and unapproved therapies from 2016 onwards, focusing on the type of melanoma model used (primary tumor and or metastatic model). PubMed® was the database in which the search was performed using mesh search algorithms resulting in 41 studies that comply with the inclusion rules of screening. Studies reviewed showed that synergy with RT or TRT had strong antitumor effects, such as tumor growth inhibition and fewer metastases, also exhibiting systemic protection. In addition, most studies were carried out on antitumor response for the implanted primary tumor, demonstrating that more studies are needed to evaluate these combined treatments in metastatic models on long-term protocols.

Cell therapy biomanufacturing: integrating biomaterial and flow-based membrane technologies for production of engineered T-cells

Adoptive T-cell therapies (ATCTs) are increasingly important for the treatment of cancer, where patient immune cells are engineered to target and eradicate diseased cells. The biomanufacturing of ATCTs involves a series of time-intensive, lab-scale steps, including isolation, activation, genetic modification, and expansion of a patient's T-cells prior to achieving a final product. Innovative modular technologies are needed to produce cell therapies at improved scale and enhanced efficacy. In this work, well-defined, bioinspired soft materials were integrated within flow-based membrane devices for improving the activation and transduction of T cells. Hydrogel coated membranes (HCM) functionalized with cell-activating antibodies were produced as a tunable biomaterial for the activation of primary human T-cells. T-cell activation utilizing HCMs led to highly proliferative T-cells that expressed a memory phenotype. Further, transduction efficiency was improved by several fold over static conditions by using a tangential flow filtration (TFF) flow-cell, commonly used in the production of protein therapeutics, to transduce T-cells under flow. The combination of HCMs and TFF technology led to increased cell activation, proliferation, and transduction compared to current industrial biomanufacturing processes. The combined power of biomaterials with scalable flow-through transduction techniques provides future opportunities for improving the biomanufacturing of ATCTs.

Systematic Review on CAR-T Cell Clinical Trials Up to 2022: Academic Center Input

The development of Chimeric Antigen Receptor T cells therapy initiated by the United States and China is still currently led by these two countries with a high number of clinical trials, with Europe lagging in launching its first trials. In this systematic review, we wanted to establish an overview of the production of CAR-T cells in clinical trials around the world, and to understand the causes of this delay in Europe. We particularly focused on the academic centers that are at the heart of research and development of this therapy. We counted 1087 CAR-T cells clinical trials on ClinicalTrials.gov (Research registry ID: reviewregistry1542) on the date of 25 January 2023. We performed a global analysis, before analyzing the 58 European trials, 34 of which sponsored by academic centers. Collaboration between an academic and an industrial player seems to be necessary for the successful development and application for marketing authorization of a CAR-T cell, and this collaboration is still cruelly lacking in European trials, unlike in the leading countries. Europe, still far behind the two leading countries, is trying to establish measures to lighten the regulations surrounding ATMPs and to encourage, through the addition of fundings, clinical trials involving these treatments.

The emerging role of regulatory cell-based therapy in autoimmune disease

Autoimmune disease, caused by unwanted immune responses to self-antigens, affects millions of people each year and poses a great social and economic burden to individuals and communities. In the course of autoimmune disorders, including rheumatoid arthritis, systemic lupus erythematosus, type 1 diabetes mellitus, and multiple sclerosis, disturbances in the balance between the immune response against harmful agents and tolerance towards self-antigens lead to an immune response against self-tissues. In recent years, various regulatory immune cells have been identified. Disruptions in the quality, quantity, and function of these cells have been implicated in autoimmune disease development. Therefore, targeting or engineering these cells is a promising therapeutic for different autoimmune diseases. Regulatory T cells, regulatory B cells, regulatory dendritic cells, myeloid suppressor cells, and some subsets of innate lymphoid cells are arising as important players among this class of cells. Here, we review the roles of each suppressive cell type in the immune system during homeostasis and in the development of autoimmunity. Moreover, we discuss the current and future therapeutic potential of each one of these cell types for autoimmune diseases.

Ultrathroughput immunomagnetic cell sorting platform

High-throughput phenotypic cell sorting is critical to the development of cell-based therapies and cell screening discovery platforms. However, current cytometry platforms are limited by throughput, number of fractionated populations that can be isolated, cell viability, and cost. We present an ultrathroughput microfluidic cell sorter capable of processing hundreds of millions of live cells per hour per device based on protein expression. This device, a next-generation microfluidic cell sorter (NG-MICS), combines multiple technologies, including 3D printing, reversible clamp sealing, and superhydrophobic treatments to create a reusable and user-friendly platform ready for deployment. The utility of such a platform is demonstrated through the rapid isolation of mature natural killer cells from peripheral blood mononuclear cells, for use in CAR-NK therapies at clinically-relevant scale.

Discovery of a Transferrin Receptor 1-Binding Aptamer and Its Application in Cancer Cell Depletion for Adoptive T-Cell Therapy Manufacturing

The clinical manufacturing of chimeric antigen receptor (CAR) T cells includes cell selection, activation, gene transduction, and expansion. While the method of T-cell selection varies across companies, current methods do not actively eliminate the cancer cells in the patient's apheresis product from the healthy immune cells. Alarmingly, it has been found that transduction of a single leukemic B cell with the CAR gene can confer resistance to CAR T-cell therapy and lead to treatment failure. In this study, we report the identification of a novel high-affinity DNA aptamer, termed tJBA8.1, that binds transferrin receptor 1 (TfR1), a receptor broadly upregulated by cancer cells. Using competition assays, high resolution cryo-EM, and de novo model building of the aptamer into the resulting electron density, we reveal that tJBA8.1 shares a binding site on TfR1 with holo-transferrin, the natural ligand of TfR1. We use tJBA8.1 to effectively deplete B lymphoma cells spiked into peripheral blood mononuclear cells with minimal impact on the healthy immune cell composition. Lastly, we present opportunities for affinity improvement of tJBA8.1. As TfR1 expression is broadly upregulated in many cancers, including difficult-to-treat T-cell leukemias and lymphomas, our work provides a facile, universal, and inexpensive approach for comprehensively removing cancerous cells from patient apheresis products for safe manufacturing of adoptive T-cell therapies.

Cytokine Activation Reveals Tissue-Imprinted Gene Profiles of Mesenchymal Stromal Cells

Development of standardized metrics to support manufacturing and regulatory approval of mesenchymal stromal cell (MSC) products is confounded by heterogeneity of MSC populations. Many reports describe fundamental differences between MSCs from various tissues and compare unstimulated and activated counterparts. However, molecular information comparing biological profiles of activated MSCs across different origins and donors is limited. To better understand common and source-specific mechanisms of action, we compared the responses of 3 donor populations each of human umbilical cord (UC) and bone marrow (BM) MSCs to TNF-α, IL-1β or IFN-γ. Transcriptome profiles were analysed by microarray and select secretome profiles were assessed by multiplex immunoassay. Unstimulated (resting) UC and BM-MSCs differentially expressed (DE) 174 genes. Signatures of TNF-α-stimulated BM and UC-MSCs included 45 and 14 new DE genes, respectively, while all but 7 of the initial 174 DE genes were expressed at comparable levels after licensing. After IL-1β activation, only 5 of the 174 DE genes remained significantly different, while 6 new DE genes were identified. IFN-γ elicited a robust transcriptome response from both cell types, yet nearly all differences (171/174) between resting populations were attenuated. Nine DE genes predominantly corresponding to immunogenic cell surface proteins emerged as a BM-MSC signature of IFN-γ activation. Changes in protein synthesis of select analytes correlated modestly with transcript levels. The dynamic responses of licensed MSCs documented herein, which attenuated heterogeneity between unstimulated populations, provide new insight into common and source-imprinted responses to cytokine activation and can inform strategic development of meaningful, standardized assays.

Untangling the Knots of Regulatory T Cell Therapy in Solid Organ Transplantation

Numerous preclinical studies have provided solid evidence supporting adoptive transfer of regulatory T cells (Tregs) to induce organ tolerance. As a result, there are 7 currently active Treg cell-based clinical trials in solid organ transplantation worldwide, all of which are early phase I or phase I/II trials. Although the results of these trials are optimistic and support both safety and feasibility, many experimental and clinical unanswered questions are slowing the progression of this new therapeutic alternative. In this review, we bring to the forefront the major challenges that Treg cell transplant investigators are currently facing, including the phenotypic and functional diversity of Treg cells, lineage stability, non-standardized ex vivo Treg cell manufacturing process, adequacy of administration route, inability of monitoring and tracking infused cells, and lack of biomarkers or validated surrogate endpoints of efficacy in clinical trials. With this plethora of interrogation marks, we are at a challenging and exciting crossroad where properly addressing these questions will determine the successful implementation of Treg cell-based immunotherapy in clinical transplantation.

Treatment with Living Drugs: Pharmaceutical Aspects of CAR T Cells

BACKGROUND

Adoptive therapy with genetically modified T cells achieves spectacular remissions in advanced hematologic malignancies. In contrast to conventional drugs, this kind of therapy applies viable autologous T cells that are ex vivo genetically engineered with a chimeric antigen receptor (CAR) and are classified as advanced therapy medicinal products.

SUMMARY

As "living drugs," CAR T cells differ from classical pharmaceutical drugs as they provide a panel of cellular capacities upon CAR signaling, including the release of effector molecules and cytokines, redirected cytotoxicity, CAR T cell amplification, active migration, and long-term persistence and immunological memory. Here, we discuss pharmaceutical aspects, the regulatory requirements for CAR T cell manufacturing, and how CAR T cell pharmacokinetics are connected with the clinical outcome.

KEY MESSAGES

From the pharmacological perspective, the development of CAR T cells with high translational potential needs to address pharmacodynamic markers to balance safety and efficacy of CAR T cells and to address pharmacokinetics with respect to trafficking, homing, infiltration, and persistence of CAR T cells.

Enhanced human T cell expansion with inverse opal hydrogels

Advanced personalized immunotherapies still have to overcome several biomedical and technical limitations before they become a routine cancer treatment in spite of recent achievements. In adoptive cell therapy (ACT), the capacity to obtain adequate numbers of therapeutic T cells in the patients following ex vivo treatment should be improved. Moreover, the time and costs to produce these T cells should be reduced. In this work, inverse opal (IOPAL) 3D hydrogels consisting of poly(ethylene) glycol (PEG) covalently combined with heparin were engineered to resemble the environment of lymph nodes, where T cells get activated and proliferate. The introduction of an IOPAL strategy allowed a precise control on the porosity of the hydrogels, providing an increase in the proliferation of primary human CD4+ T cells, when compared with state-of-the-art expansion systems. Additionally, the IOPAL hydrogels also showed a superior expansion compared to hydrogels with the same composition, but without the predetermined pore structure. In summary, we have shown the beneficial effect of having an IOPAL architecture in our 3D hydrogels to help achieving large numbers of cells, while maintaining the desired selected phenotypes required for ACT.

Synthetic cells in biomedical applications

Synthetic cells are engineered vesicles that can mimic one or more salient features of life. These features include directed localization, sense-and-respond behavior, gene expression, metabolism, and high stability. In nanomedicine, many of these features are desirable capabilities of drug delivery vehicles but are difficult to engineer. In this focus article, we discuss where synthetic cells offer unique advantages over nanoparticle and living cell therapies. We review progress in the engineering of the above life-like behaviors and how they are deployed in nanomedicine. Finally, we assess key challenges synthetic cells face before being deployed as drugs and suggest ways to overcome these challenges. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Biology-Inspired Nanomaterials > Lipid-Based Structures.

A comprehensive report of long-term stability data for a range ATMPs: A need to develop guidelines for safe and harmonized stability studies

BACKGROUND AIMS

Advanced therapy medicinal products (ATMPs) are novel drugs based on genes, cells or tissues developed to treat many different diseases. Stability studies of each new ATMP need to be performed to define its shelf life and guarantee efficacy and safety upon infusion, and these are presently based on guidelines originally drafted for standard pharmaceutical drugs, which have properties and are stored in conditions quite different from cell products. The aim of this report is to provide evidence-based information for stability studies on ATMPs that will facilitate the interlaboratory harmonization of practices in this area.

METHODS

We have collected and analyzed the results of stability studies on 19 different cell-based experimental ATMPs, produced by five authorized cell factories forming the Lombardy "Plagencell network" for use in 36 approved phase I/II clinical trials; most were cryopreserved and stored in liquid nitrogen vapors for 1 to 13 years.

RESULTS

The cell attributes collected in stability studies included cell viability, immunophenotype and potency assays, in particular immunosuppression, cytotoxicity, cytokine release and proliferation/differentiation capacity. Microbiological attributes including sterility, endotoxin levels and mycoplasma contamination were also analyzed. All drug products (DPs), cryopreserved in various excipients containing 10% DMSO and in different primary containers, were very stable long term at <-150°C and did not show any tendency for diminished viability or efficacy for up to 13.5 years.

CONCLUSIONS

Our data indicate that new guidelines for stability studies, specific for ATMPs and based on risk analyses, should be drafted to harmonize practices, significantly reduce the costs of stability studies without diminishing safety. Some specific suggestions are presented in the discussion.

In vitro naphthylquinoxaline thymidine conjugate and UVA treated cancer cells are effective therapeutic vaccines for tumors in vivo with CpG as the adjuvant

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Effective tumor immunotherapy with in vitro NAP-UVA treated cancer cells per se

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Marked survival improvement with CpG as the specific adjuvant

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Enhanced tumor specific and infiltrating active T cells by treatment vaccine

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Validated efficacy on established tumors with increased dosages

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Potential personalized immunotherapy applications

Introduction

Cancer cells induced into immunogenic cell death (ICD) in vitro can be directly used as a whole cell vaccine for tumor immunotherapy with many advantages, especially enacting immediate and intense ‘eat me’ signals to engage immune system. Unfortunately, there have been few successes with in vitro ICD cancer cells as a treatment vaccine.

Objective

To demonstrate that cancer cells treated in vitro with a new class of potent ICD inducer, naphthylquinoxaline thymidine conjugate (NAP) followed by UVA irradiation would be able to act as an effective tumor immunotherapy directly.

Methods

The therapeutic potentials of treated cancer cell plus different vaccine adjuvants were assessed by in vivo liver tumor model and in vitro mixed lymphocyte reaction studies. The elicited activated T cells were determined with immunohistochemistry and T cell induced cytotoxicity studies.

Results

Treatment of established H22 tumor with in vitro NAP and UVA treated cancer cell vaccine led to significantly improved survival. Further mixed lymphocyte reaction study implied that adjuvants alum and CpG would improve the therapeutic potential whereas poly IC would not be as effective. Subsequent in vivo validation of alum and CpG adjuvants indicated that only CpG in NAP and UVA treated cell vaccine resulted in markedly enhanced survival (median at 71 days and 50% tumor-free) as compared with PBS group (14.5 days, 0%) and CpG alone (36 days, 0%). It was revealed that the enhanced efficacy by CpG was specific to NAP and UVA treated cells. Moreover, the effective tumor immunotherapy was achieved through the infiltration of active CD4 and CD8 T cells in tumors and acquisition of cancer cell-specific cytotoxic CD8 T cells.

Conclusion

In vitro NAP and UVA treated cancer cells plus CpG adjuvant are effective tumor therapeutic vaccines per se.

Inertial Microfluidic Purification of CAR-T-Cell Products

Chimeric antigen receptor T (CAR-T) cell therapy is rapidly becoming a frontline cancer therapy. However, the manufacturing process is time-, labor- and cost-intensive, and it suffers from significant bottlenecks. Many CAR-T products fail to reach the viability release criteria set by regulators for commercial cell therapy products. This results in non-recoupable costs for the manufacturer and is detrimental to patients who may not receive their scheduled treatment or receive out-of-specification suboptimal formulation. It is demonstrated here that inertial microfluidics can, within minutes, efficiently deplete nonviable cells from low-viability CAR-T cell products. The percentage of viable cells increases from 40% (SD ± 0.12) to 71% (SD ± 0.09) for untransduced T cells and from 51% (SD ± 0.12) to 71% (SD ± 0.09) for CAR-T cells, which meets the clinical trials' release parameters. In addition, the processing of CAR-T cells formulated in CryStor yields a 91% reduction in the amount of the cryoprotectant dimethyl sulfoxide. Inertial microfluidic processing has no detrimental effects on the proliferation and cytotoxicity of CAR-T cells. Interestingly, ≈50% of T-regulatory and T-suppressor cells are depleted, suggesting the potential for inertial microfluidic processing to tune the phenotypical composition of T-cell products.

T Cell Engaging Immunotherapies, Highlighting Chimeric Antigen Receptor (CAR) T Cell Therapy

In the past decade, chimeric antigen receptor (CAR) T cell technology has revolutionized cancer immunotherapy. This strategy uses synthetic CARs to redirect the patient's own immune cells to recognize specific antigens expressed on the surface of tumor cells. The unprecedented success of anti-CD19 CAR T cell therapy against B cell malignancies has resulted in its approval by the US Food and Drug Administration (FDA) in 2017. However, major scientific challenges still remain to be addressed for the broad use of CAR T cell therapy. These include severe toxicities, limited efficacy against solid tumors, and immune suppression in the hostile tumor microenvironment. Furthermore, CAR T cell therapy is a personalized medicine of which the production is time- and resource-intensive, which makes it very expensive. All these factors drive new innovations to engineer more powerful CAR T cells with improved antitumor activity, which are reviewed in this manuscript.

Production and Application of CAR T Cells: Current and Future Role of Europe

Rapid developments in the field of CAR T cells offer important new opportunities while at the same time increasing numbers of patients pose major challenges. This review is summarizing on the one hand the state of the art in CAR T cell trials with a unique perspective on the role that Europe is playing. On the other hand, an overview of reproducible processing techniques is presented, from manual or semi-automated up to fully automated manufacturing of clinical-grade CAR T cells. Besides regulatory requirements, an outlook is given in the direction of digitally controlled automated manufacturing in order to lower cost and complexity and to address CAR T cell products for a greater number of patients and a variety of malignant diseases.

Regulatory T Cell Therapy of Graft-versus-Host Disease: Advances and Challenges

Graft-versus-host disease (GVHD) is the leading cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Immunomodulation using regulatory T cells (Tregs) offers an exciting option to prevent and/or treat GVHD as these cells naturally function to maintain immune homeostasis, can induce tolerance following HSCT, and have a tissue reparative function. Studies to date have established a clinical safety profile for polyclonal Tregs. Functional enhancement through genetic engineering offers the possibility of improved potency, specificity, and persistence. In this review, we provide the most up to date preclinical and clinical data on Treg cell therapy with a particular focus on GVHD. We discuss the different Treg subtypes and highlight the pharmacological and genetic approaches under investigation to enhance the application of Tregs in allo-HSCT. Lastly, we discuss the remaining challenges for optimal clinical translation and provide insights as to future directions of the field.

Cryopreservation of NK and T Cells Without DMSO for Adoptive Cell-Based Immunotherapy

Dimethylsufoxide (DMSO) being universally used as a cryoprotectant in clinical adoptive cell-therapy settings to treat hematological malignancies and solid tumors is a growing concern, largely due to its broad toxicities. Its use has been associated with significant clinical side effects-cardiovascular, neurological, gastrointestinal, and allergic-in patients receiving infusions of cell-therapy products. DMSO has also been associated with altered expression of natural killer (NK) and T-cell markers and their in vivo function, not to mention difficulties in scaling up DMSO-based cryoprotectants, which introduce manufacturing challenges for autologous and allogeneic cellular therapies, including chimeric antigen receptor (CAR)-T and CAR-NK cell therapies. Interest in developing alternatives to DMSO has resulted in the evaluation of a variety of sugars, proteins, polymers, amino acids, and other small molecules and osmolytes as well as modalities to efficiently enable cellular uptake of these cryoprotectants. However, the DMSO-free cryopreservation of NK and T cells remains difficult. They represent heterogeneous cell populations that are sensitive to freezing and thawing. As a result, clinical use of cryopreserved cell-therapy products has not moved past the use of DMSO. Here, we present the state of the art in the development and use of cryopreservation options that do not contain DMSO toward clinical solutions to enable the global deployment of safer adoptively transferred cell-based therapies.

Accelerating vein-to-vein cell therapy workflows with new bioanalytical strategies

Cell therapies represent a new era of treatment modalities for cancer. Through agile bioprocessing and bioengineering, patient-derived T-cells can be directed toward cancer biomarkers to impart a more robust and targeted immune response. In order to avoid delays in critical treatment timeframes, new bioanalytical tools are needed to accelerate, streamline, and maximize the throughput of T-cell bioprocessing. This review offers a survey of recent biotechnological advances supporting enhanced and expedited biomanufacturing workflows for autologous and allogeneic cell therapies, ranging from novel genetic engineering techniques and cell sorting platforms to stem cells and tumor organoid models. Collectively, these methods can increase the clinical impact of cancer therapeutics by improving the specificity, efficacy, and timely delivery of cell-based products.

CRISPR/Cas9 technology: towards a new generation of improved CAR-T cells for anticancer therapies

Chimeric antigen receptor (CAR)-modified T cells have raised among other immunotherapies for cancer treatment, being implemented against B-cell malignancies. Despite the promising outcomes of this innovative technology, CAR-T cells are not exempt from limitations that must yet to be overcome in order to provide reliable and more efficient treatments against other types of cancer. The purpose of this review is to shed light on the field of CAR-T cell gene editing for therapy universalization and further enhancement of antitumor function. Several studies have proven that the disruption of certain key genes is essential to boost immunosuppressive resistance, prevention of fratricide, and clinical safety. Due to its unparalleled simplicity, feasibility to edit multiple gene targets simultaneously, and affordability, CRISPR/CRISPR-associated protein 9 system has been proposed in different clinical trials for such CAR-T cell improvement. The combination of such powerful technologies is expected to provide a new generation of CAR-T cell-based immunotherapies for clinical application.

Forced degradation of cell-based medicinal products guided by flow imaging microscopy: Explorative studies with Jurkat cells

Cell-based medicinal products (CBMPs) offer ground-breaking opportunities to treat diseases with limited or no therapeutic options. However, the intrinsic complexity of CBMPs results in great challenges with respect to analytical characterization and stability assessment. In our study, we submitted Jurkat cell suspensions to forced degradation studies mimicking conditions to which CBMPs might be exposed from procurement of cells to administration of the product. Flow imaging microscopy assisted by machine learning was applied for determination of cell viability and concentration, and quantification of debris particles. Additionally, orthogonal cell characterization techniques were used. Thawing of cells at 5 °C was detrimental to cell viability and resulted in high numbers of debris particles, in contrast to thawing at 37 °C or 20 °C which resulted in better stability. After freezing of cell suspensions at -18 °C in presence of dimethyl sulfoxide (DMSO), a DMSO concentration of 2.5% (v/v) showed low stabilizing properties, whereas 5% or 10% was protective. Horizontal shaking of cell suspensions did not affect cell viability, but led to a reduction in cell concentration. Fetal bovine serum (10% [v/v]) protected the cells during shaking. In conclusion, forced degradation studies with application of orthogonal analytical characterization methods allow for CBMP stability assessment and formulation screening.

Development and Validation of a Good Manufacturing Process for IL-4-Driven Expansion of Chimeric Cytokine Receptor-Expressing CAR T-Cells

Adoptive cancer immunotherapy using chimeric antigen receptor (CAR) engineered T-cells holds great promise, although several obstacles hinder the efficient generation of cell products under good manufacturing practice (GMP). Patients are often immune compromised, rendering it challenging to produce sufficient numbers of gene-modified cells. Manufacturing protocols are labour intensive and frequently involve one or more open processing steps, leading to increased risk of contamination. We set out to develop a simplified process to generate autologous gamma retrovirus-transduced T-cells for clinical evaluation in patients with head and neck cancer. T-cells were engineered to co-express a panErbB-specific CAR (T1E28z) and a chimeric cytokine receptor (4αβ) that permits their selective expansion in response to interleukin (IL)-4. Using peripheral blood as starting material, sterile culture procedures were conducted in gas-permeable bags under static conditions. Pre-aliquoted medium and cytokines, bespoke connector devices and sterile welding/sealing were used to maximise the use of closed manufacturing steps. Reproducible IL-4-dependent expansion and enrichment of CAR-engineered T-cells under GMP was achieved, both from patients and healthy donors. We also describe the development and approach taken to validate a panel of monitoring and critical release assays, which provide objective data on cell product quality.

Induced Pluripotent Stem Cells (iPSCs) Provide a Potentially Unlimited T Cell Source for CAR-T Cell Development and Off-the-Shelf Products

Chimeric antigen receptor T (CAR-T) cell therapy has been increasingly conducted for cancer patients in clinical settings. Progress in this therapeutic approach is hampered by the lack of a solid manufacturing process, T lymphocytes, and tumor-specific antigens. T cell source used in CAR-T cell therapy is derived predominantly from the patient's own T lymphocytes, which makes this approach impracticable to patients with progressive diseases and T leukemia. The generation of autologous CAR-T cells is time-consuming due to the lack of readily available T lymphocytes and is not applicable for third-party patients. Pluripotent stem cells, such as human induced pluripotent stem cells (hiPSCs), can provide an unlimited T cell source for CAR-T cell development with the potential of generating off-the-shelf T cell products. T-iPSCs (iPSC-derived T cells) are phenotypically defined, expandable, and as functional as physiological T cells. The combination of iPSC and CAR technologies provides an exciting opportunity to oncology and greatly facilitates cell-based therapy for cancer patients. However, T-iPSCs, in combination with CARs, are at the early stage of development and need further pre-clinical and clinical studies. This review will critically discuss the progress made in iPSC-derived T cells and provides a roadmap for the development of CAR iPSC-derived T cells and off-the-shelf T-iPSCs.

Industrializing engineered autologous T cells as medicines for solid tumours

Cell therapy is one of the fastest growing areas in the pharmaceutical industry, with considerable therapeutic potential. However, substantial challenges regarding the utility of these therapies will need to be addressed before they can become mainstream medicines with applicability similar to that of small molecules or monoclonal antibodies. Engineered T cells have achieved success in the treatment of blood cancers, with four chimeric antigen receptor (CAR)-T cell therapies now approved for the treatment of B cell malignancies based on their unprecedented efficacy in clinical trials. However, similar results have not yet been achieved in the treatment of the much larger patient population with solid tumours. For cell therapies to become mainstream medicines, they may need to offer transformational clinical effects for patients and be applicable in disease settings that remain unaddressed by simpler approaches. This Perspective provides an industry perspective on the progress achieved by engineered T cell therapies to date and the opportunities and current barriers for accessing broader patient populations, and discusses the solutions and new development strategies required to fully industrialize the therapeutic potential of engineered T cells as medicines.

Cell therapies in the clinic

Cell therapies have emerged as a promising therapeutic modality with the potential to treat and even cure a diverse array of diseases. Cell therapies offer unique clinical and therapeutic advantages over conventional small molecules and the growing number of biologics. Particularly, living cells can simultaneously and dynamically perform complex biological functions in ways that conventional drugs cannot; cell therapies have expanded the spectrum of available therapeutic options to include key cellular functions and processes. As such, cell therapies are currently one of the most investigated therapeutic modalities in both preclinical and clinical settings, with many products having been approved and many more under active clinical investigation. Here, we highlight the diversity and key advantages of cell therapies and discuss their current clinical advances. In particular, we review 28 globally approved cell therapy products and their clinical use. We also analyze >1700 current active clinical trials of cell therapies, with an emphasis on discussing their therapeutic applications. Finally, we critically discuss the major biological, manufacturing, and regulatory challenges associated with the clinical translation of cell therapies.

Lymphocyte expansion in bioreactors: upgrading adoptive cell therapy

Bioreactors are essential tools for the development of efficient and high-quality cell therapy products. However, their application is far from full potential, holding several challenges when reconciling the complex biology of the cells to be expanded with the need for a manufacturing process that is able to control cell growth and functionality towards therapy affordability and opportunity. In this review, we discuss and compare current bioreactor technologies by performing a systematic analysis of the published data on automated lymphocyte expansion for adoptive cell therapy. We propose a set of requirements for bioreactor design and identify trends on the applicability of these technologies, highlighting the specific challenges and major advancements for each one of the current approaches of expansion along with the opportunities that lie in process intensification. We conclude on the necessity to develop targeted solutions specially tailored for the specific stimulation, supplementation and micro-environmental needs of lymphocytes’ cultures, and the benefit of applying knowledge-based tools for process control and predictability.