Adoptive cellular therapy: a race to the finish line

Redefining quality in cell and gene therapies: Lessons from implementing electronic QMS in academic cGMP facility

Manufacturing cell and gene therapies (CGTs) involves complex processes that require robust quality management, especially within academic current Good Manufacturing Practice (cGMP) facilities, where resources are often limited. Traditional paper-based quality management systems (QMSs), while initially convenient, often become burdensome, leading to errors, poor traceability, and compliance risks. Electronic QMSs (eQMSs) are gaining recognition for their ability to centralize and automate key quality processes, significantly enhancing operational efficiency and regulatory readiness. Through an in-depth case study of the University of Southern California and Children's Hospital of Los Angeles academic cGMP facility, this review demonstrates tangible improvements achieved by adopting an eQMS. Practical insights gained from this experience are shared, including careful selection of eQMS platforms, phased rollout strategies, and comprehensive staff training. The review also addresses common implementation challenges and suggests practical solutions to overcome them. Lessons learned and strategies discussed here can serve as valuable guidance for other academic institutions considering eQMS adoption. Ultimately, embracing an eQMS enables academic CGT manufacturers to operate more efficiently and stay ahead in a fast-moving field.

Functionalized Poly(ethylene Glycol) Diacrylate Scaffolds for In Situ Immunomodulation of Dendritic Cells Targeting Melanoma Tumor

Various immunotherapeutic strategies are being developed to fight cancer, which is one of the leading causes of mortality. Dendritic cells (DCs), being professional antigen-presenting cells, after efficient manipulation with tumor-associated antigens, can lead to effective T-cell recruitment and activation at the tumor site, resulting in cytotoxic T-cell-mediated cancer cell killing. To circumvent the inefficiencies of ex vivo DC modification and patient infusion, an alternative strategy involving in situ DC activation has been explored here. Here, the vaccine components are tumor lysates, as antigens, and polyinosinic:polycytidylic acid (poly(I:C)), a toll-like receptor-3 (TLR3) agonist, as an adjuvant. Our in vitro studies demonstrate that complexing poly(I:C) with a carrier molecule, chitosan, enhances its stability and accessibility to TLR3 in the DC endosomal membrane. Material-based localized delivery of immunomodulatory factors is known to improve their stability and reduce their off-target side effects. Here, PEGDA-PLL-based macroporous scaffolds allow easy recruitment of host cells, thereby enabling effective interaction between the vaccine components loaded on them and the infiltrating immune cells. The vaccine components present in the scaffold facilitate efficient DC activation and migration, leading to subsequent T-cell activation and antitumor response, as shown by our in vivo studies.

In-depth analysis of the safety of CAR-T cell therapy for solid tumors

In recent years, the rapid progress in oncology, immunology, and molecular biology has dramatically advanced cancer immunotherapy, particularly CAR-T cell therapy. This innovative approach involves engineering a patient's T cells to express receptors that specifically target tumor antigens, enhancing their ability to identify and eliminate cancer cells. However, the effectiveness of CAR-T therapy in solid tumors is often hampered by the challenging tumor microenvironment (TME). The complex TME includes dense stroma that obstructs T cell infiltration, abnormal blood vessel structures leading to hypoxia, and an acidic pH, all of which hinder CAR-T cell function. Additionally, the presence of immunosuppressive factors in the TME reduces the efficacy of CAR-T cells, making successful targeting of tumors more difficult. The safety of CAR-T therapy has gained interest, especially CAR-T therapy has shown considerable effectiveness in various cancers, with notable results in multiple myeloma and hepatocellular carcinoma, among others. Nonetheless, CAR-T cell therapy is associated with several adverse reactions primarily driven by heightened levels of proinflammatory cytokines. These reactions include cytokine release syndrome (CRS), neurotoxicity (CANS), and organ toxicity, often leading to serious complications. CRS, characterized by systemic inflammation due to cytokine release, can escalate to severe organ dysfunction. It typically occurs within the first week post-infusion, correlating with CAR-T cell expansion and often presents with fever and hypotension. Meanwhile, CANS encompasses neurological issues ranging from mild symptoms to severe seizures, possibly exacerbated by CRS. Organ toxicity can also arise from CAR-T therapy, with potential damage affecting the gastrointestinal tract, kidneys, liver, and lungs, often tied to shared antigens found in both tumor and healthy tissues. Moreover, long-term effects like cytokine-associated hematotoxicity (CAHT) and secondary malignancies represent significant concerns that could affect the patient's quality of life post-treatment. The long-term adverse effects and challenges in treating solid tumors underscore the need for ongoing research. Strategies to improve CAR-T cell efficacy, minimize adverse reactions, and enhance patient safety are critical. Future explorations could include designing CAR-T cells to better navigate the TME, identifying specific target antigen profiles to minimize off-target damage, and developing adjunct therapies to mitigate cytokine-related toxicity. Continued monitoring for long-term effects will also be paramount in improving patient outcomes and maintaining their quality of life. Overall, while CAR-T therapy holds great promise, it must be administered with careful consideration of potential side effects and rigorous management strategies to ensure patient safety and treatment efficacy.

Infections in Patients with Solid Tumors Undergoing Adoptive Cellular Therapy

Adoptive cellular therapy (ACT) is an increasingly widely used treatment approach for malignancy. While infectious complications of ACT have been well described in patients with hematologic malignancies, limited data are available on the epidemiology of infections in patients with solid tumors. The purpose of this study was to describe the epidemiology of infections occurring within the first 180 days in adult patients with solid tumors treated with ACT and to identify risk factors predisposing these patients to infection. Data on 132 adult patients with solid tumors undergoing ACT between August 2014 and November 2021 at Memorial Sloan Kettering Cancer Center were collected. Infections were documented from the day of ACT infusion through day 180 postinfusion. Overall, 28 of 132 patients (21.2%) experienced 33 infections within the first 30 days of ACT, and 17 of 131 surviving patients (13%) were diagnosed with 24 infections between day 31 and day 180. Infection-related mortality was low. The majority of infections were bacterial. While male gender, older age, Eastern Cooperative Oncology Group (ECOG) performance status (PS) at time of ACT infusion, tocilizumab receipt, and cytokine release syndrome treated with tocilizumab were associated with shorter time to first infection on univariable analysis, only ECOG PS and tocilizumab receipt remained independent risk factors in the multivariable analysis. The proportion of patients with solid tumors experiencing early or late infections after ACT was lower compared to that reported among patients with B cell malignancies after chimeric antigen receptor T cell therapy. Most observed infections were primarily bacterial with low infection-related mortality; the incidence of viral and fungal infections was low. Based on the low frequency and timing of infections relative to neutropenia, antibacterial and antifungal prophylaxis are not likely to be beneficial. ECOG PS ≥2 and tocilizumab receipt were identified as significant predictors for infection after ACT, likely signaling an individual's debilitated state that predisposes to infection. Additional work to parse out confounders is needed to better identify risk factors for infection.

Mechanoimmunology of T-Cell Activation

T-cell activation, a pivotal process in the adaptive immune response, is initiated when the T cell receptor (TCR) recognises and binds to antigenic peptide-major histocompatibility complex (pMHC) molecules on the cell membrane. Emerging evidence indicates that mechanical cues regulate T-cell activation by modulating TCR signalling and mechanotransduction pathways, although the precise underlying mechanisms remain elusive. This review highlights recent findings suggesting that the TCR functions as a mechanosensor, capable of sensing and transmitting mechanical forces through conformational changes. Key steps in T-cell mechanotransduction are discussed, including the roles of the cytoskeleton, mechanosensitive channels such as Piezo 1 and microvilli in facilitating activation. Additionally, we analyse the mechanical responses of chimeric antigen receptor T cells. Understanding the mechanobiological mechanisms underlying T-cell activation offers novel insights and potential strategies for advancing immunotherapies and treating immune-related disorders.

The role of mitochondria in tumor metastasis and advances in mitochondria-targeted cancer therapy

Mitochondria are central actors in diverse physiological phenomena ranging from energy metabolism to stress signaling and immune modulation. Accumulating scientific evidence points to the critical involvement of specific mitochondrial-associated events, including mitochondrial quality control, intercellular mitochondrial transfer, and mitochondrial genetics, in potentiating the metastatic cascade of neoplastic cells. Furthermore, numerous recent studies have consistently emphasized the highly significant role mitochondria play in coordinating the regulation of tumor-infiltrating immune cells and immunotherapeutic interventions. This review provides a comprehensive and rigorous scholarly investigation of this subject matter, exploring the intricate mechanisms by which mitochondria contribute to tumor metastasis and examining the progress of mitochondria-targeted cancer therapies.

Polyphenols as Immunomodulators and Epigenetic Modulators: An Analysis of Their Role in the Treatment and Prevention of Breast Cancer

Breast cancer poses a substantial health challenge for women globally. Recently, there has been a notable increase in scholarly attention regarding polyphenols, primarily attributed to not only the adverse effects associated with conventional treatments but also their immune-preventive impacts. Polyphenols, nature-derived substances present in vegetation, including fruits and vegetables, have received considerable attention in various fields of science due to their probable wellness merits, particularly in the treatment and hindrance of cancer. This review focuses on the immunomodulatory effects of polyphenols in breast cancer, emphasizing their capacity to influence the reaction of adaptive and innate immune cells within the tumor-associated environment. Polyphenols are implicated in the modulation of inflammation, the enhancement of antioxidant defenses, the promotion of epigenetic modifications, and the support of immune functions. Additionally, these compounds have been shown to influence the activity of critical immune cells, including macrophages and T cells. By targeting pathways involved in immune evasion, polyphenols may augment the capacity of the defensive system to detect and eliminate tumors. The findings suggest that incorporating polyphenol-rich foods into the diet could offer a promising, collaborative (integrative) approach to classical breast cancer remedial procedures by regulating how the defense mechanism interacts with the disease.

Colorectal cancer: Recent advances in management and treatment

Colorectal cancer (CRC) is the third most common cancer worldwide, and the second most common cause of cancer-related death. In 2020, the estimated number of deaths due to CRC was approximately 930000, accounting for 10% of all cancer deaths worldwide. Accordingly, there is a vast amount of ongoing research aiming to find new and improved treatment modalities for CRC that can potentially increase survival and decrease overall morbidity and mortality. Current management strategies for CRC include surgical procedures for resectable cases, and radiotherapy, chemotherapy, and immunotherapy, in addition to their combination, for non-resectable tumors. Despite these options, CRC remains incurable in 50% of cases. Nonetheless, significant improvements in research techniques have allowed for treatment approaches for CRC to be frequently updated, leading to the availability of new drugs and therapeutic strategies. This review summarizes the most recent therapeutic approaches for CRC, with special emphasis on new strategies that are currently being studied and have great potential to improve the prognosis and lifespan of patients with CRC.

Recent Advancements in Cell-Based Therapies in Melanoma

Malignant melanoma outcomes have drastically changed in recent years due to the introduction of immune checkpoint inhibitors (ICIs). However, many patients still experience intolerable side effects, therapy resistance, and disease progression on ICI therapy. Therefore, there remains a need for novel therapeutics that address this gap in treatment options. Cell-based therapies have gained wide attention as a therapeutic option that could address this gap in treatment options for advanced melanoma. These therapies work by extracting certain cell types produced in the human body such as T-cells, modifying them based on a specific target, and transfusing them back into the patient. In the realm of cancer therapy, cell-based therapies utilize immune cells to target tumor cells while sparing healthy cells. Recently, the Food and Drug Administration (FDA) has approved the usage of lifileucel, a tumor-infiltrating lymphocyte (TIL) therapy, in advanced melanoma. This came following recent results from the C-144-01 study (NCT02360579), which demonstrated the efficacy and safety of TILs in metastatic melanoma patients who otherwise failed on standard ICI/targeted therapy. Thus, the results of this trial as well as the recent FDA approval have proven the viability of utilizing cell-based therapies to fill the gap in treatment options for patients with advanced melanoma. This review aims to provide a comprehensive overview of major cell-based therapies that have been utilized in melanoma by delineating results of the most recent multi-center phase II/ III clinical trials that evaluate the efficacy and safety of major cell-based therapies in melanoma. Additionally, we provide a summary of current limitations in each cell-based therapeutic option as well as a future direction of how to further extrapolate these cell-based therapies in advanced melanoma.

Pharmacologic HIF stabilization activates costimulatory receptor expression to increase antitumor efficacy of adoptive T cell therapy

Adoptive cell transfer (ACT) is a therapeutic strategy to augment antitumor immunity. Here, we report that ex vivo treatment of mouse CD8+ T cells with dimethyloxalylglycine (DMOG), a stabilizer of hypoxia-inducible factors (HIFs), induced HIF binding to the genes encoding the costimulatory receptors CD81, GITR, OX40, and 4-1BB, leading to increased expression. DMOG treatment increased T cell killing of melanoma cells, which was further augmented by agonist antibodies targeting each costimulatory receptor. In tumor-bearing mice, ACT using T cells treated ex vivo with DMOG and agonist antibodies resulted in decreased tumor growth compared to ACT using control T cells and increased intratumoral markers of CD8+ T cells (CD7, CD8A, and CD8B1), natural killer cells (NCR1 and KLRK1), and cytolytic activity (perforin-1 and tumor necrosis factor-α). Costimulatory receptor gene expression was also induced when CD8+ T cells were treated with three highly selective HIF stabilizers that are currently in clinical use.

Inhibition of DNMTs increases neoantigen-reactive T-cell toxicity against microsatellite-stable colorectal cancer in combination with radiotherapy

The therapeutic efficacy of immunotherapy is limited in the majority of colorectal cancer patients due to the low mutational and neoantigen burdens in this immunogenically "cold" microsatellite stability-colorectal cancer (MSS-CRC) cohort. Here, we showed that DNA methyltransferase (DNMT) inhibition upregulated neoantigen-bearing gene expression in MSS-CRC, resulting in increased neoantigen presentation by MHC class I in tumor cells and leading to increased neoantigen-specific T-cell activation in combination with radiotherapy. The cytotoxicity of neoantigen-reactive T cells (NRTs) to DNMTi-treated cancer cells was highly cytotoxic, and these cells secreted high IFNγ levels targeting MSS-CRC cells after ex vivo expansion of NRTs with DNMTi-treated tumor antigens. Moreover, the therapeutic efficacy of NRTs further increased when NRTs were combined with radiotherapy in vivo. Administration of DNMTi-augmented NRTs and radiotherapy achieved an ∼50 % complete response and extended survival time in an immunocompetent MSS-CRC animal model. Moreover, remarkably, splenocytes from these mice exhibited neoantigen-specific T-cell responses, indicating that radiotherapy in combination with DNMTi-augmented NRTs prolonged and increased neoantigen-specific T-cell toxicity in MSS-CRC patients. In addition, these DNMTi-augmented NRTs markedly increase the therapeutic efficacy of cancer vaccines and immune checkpoint inhibitors (ICIs). These data suggest that a combination of radiotherapy and epi-immunotherapeutic agents improves the function of ex vivo-expanded neoantigen-reactive T cells and increases the tumor-specific cytotoxic effector population to enhance therapeutic efficacy in MSS-CRC.

Current Trends and Innovative Approaches in Cancer Immunotherapy

Immunotherapy is one of the most promising therapeutic approaches in the field of cancer treatment. As a tumor progresses, tumor cells employ an array of immune-regulatory mechanisms to suppress immune responses within the tumor microenvironment. Using our understanding of these mechanisms, cancer immunotherapy has been developed to enhance the immune system's effectiveness in treating cancer. Numerous cancer immunotherapies are currently in clinical use, yet many others are either in different stages of development or undergoing clinical studies. In this paper, we briefly discuss the features and current status of cancer immunotherapies. This includes the application of monoclonal antibodies, immune checkpoint inhibitors, adoptive cell therapy, cytokine therapy, cancer vaccines, and gene therapy, all of which have gained significant recognition in clinical practice. Additionally, we discuss limitations that may hinder successful clinical utilization and promising strategies, such as combining immunotherapy with nanotechnology.

IL-2 based cancer immunotherapies: an evolving paradigm

Discovered over 4 decades ago in the supernatants of activated T cells, interleukin-2 (IL-2) is a potent pleiotropic cytokine involved in the regulation of immune responses. It is required for effector T cell expansion and differentiation as well as for peripheral tolerance induced by regulatory T cells. High-dose IL-2 treatment was the first FDA-approved immunotherapy for renal cell carcinoma and melanoma, achieving single agent complete and durable responses, albeit only in a small proportion of patients. The therapeutic potential of wild type IL-2 is clinically limited by its short half-life and severe vascular toxicity. Moreover, the activation of regulatory T cells and the terminal differentiation of effector T cells on IL-2 pose additional restrictions. To overcome the toxicity of IL-2 in order to realize its full potential for patients, several novel engineering strategies are being developed and IL-2 based immunotherapy for cancer has emerged as a burgeoning field of clinical and experimental research. In addition, combination of IL-2 with PD-1/L1 pathway blockade shows vastly improved anti-tumor efficacy over either monotherapy in preclinical tumor models. In this review we discuss the biological characteristics of IL-2 and its receptors, as well as its efficacy and treatment limiting toxicities in cancer patients. We also explore the efforts aimed at developing novel and safer IL-2 therapies to harness the full therapeutic potential of this cytokine.

Enhancing cancer therapy: the integration of oncolytic virus therapy with diverse treatments

As one of the significant challenges to human health, cancer has long been a focal point in medical treatment. With ongoing advancements in the field of medicine, numerous methodologies for cancer therapy have emerged, among which oncolytic virus therapy has gained considerable attention. However, oncolytic viruses still exhibit limitations. Combining them with various therapies can further enhance the efficacy of cancer treatment, offering renewed hope for patients. In recent research, scientists have recognized the promising prospect of amalgamating oncolytic virus therapy with diverse treatments, potentially surmounting the restrictions of singular approaches. The central concept of this combined therapy revolves around leveraging oncolytic virus to incite localized tumor inflammation, augmenting the immune response for immunotherapeutic efficacy. Through this approach, the patient's immune system can better recognize and eliminate cancer cells, simultaneously reducing tumor evasion mechanisms against the immune system. This review delves deeply into the latest research progress concerning the integration of oncolytic virus with diverse treatments and its role in various types of cancer therapy. We aim to analyze the mechanisms, advantages, potential challenges, and future research directions of this combination therapy. By extensively exploring this field, we aim to instill renewed hope in the fight against cancer.

Identification of a clinically efficacious CAR T cell subset in diffuse large B cell lymphoma by dynamic multidimensional single-cell profiling

Chimeric antigen receptor (CAR) T cells used for the treatment of B cell malignancies can identify T cell subsets with superior clinical activity. Here, using infusion products of individuals with large B cell lymphoma, we integrated functional profiling using timelapse imaging microscopy in nanowell grids with subcellular profiling and single-cell RNA sequencing to identify a signature of multifunctional CD8+ T cells (CD8-fit T cells). CD8-fit T cells are capable of migration and serial killing and harbor balanced mitochondrial and lysosomal volumes. Using independent datasets, we validate that CD8-fit T cells (1) are present premanufacture and are associated with clinical responses in individuals treated with axicabtagene ciloleucel, (2) longitudinally persist in individuals after treatment with CAR T cells and (3) are tumor migrating cytolytic cells capable of intratumoral expansion in solid tumors. Our results demonstrate the power of multimodal integration of single-cell functional assessments for the discovery and application of CD8-fit T cells as a T cell subset with optimal fitness in cell therapy.

Challenges and innovations in CAR-T cell therapy: a comprehensive analysis

Recent years have seen a marked increase in research on chimeric antigen receptor T (CAR-T) cells, with specific relevance to the treatment of hematological malignancies. Here, the structural principles, iterative processes, and target selection of CAR-T cells for therapeutic applications are described in detail, as well as the challenges faced in the treatment of solid tumors and hematological malignancies. These challenges include insufficient infiltration of cells, off-target effects, cytokine release syndrome, and tumor lysis syndrome. In addition, directions in the iterative development of CAR-T cell therapy are discussed, including modifications of CAR-T cell structures, improvements in specificity using multi-targets and novel targets, the use of Boolean logic gates to minimize off-target effects and control toxicity, and the adoption of additional protection mechanisms to improve the durability of CAR-T cell treatment. This review provides ideas and strategies for the development of CAR-T cell therapy through an in-depth exploration of the underlying mechanisms of action of CAR-T cells and their potential for innovative modification.

CAR-NKT Cells in Asthma: Use of NKT as a Promising Cell for CAR Therapy

NKT cells, unique lymphocytes bridging innate and adaptive immunity, offer significant potential for managing inflammatory disorders like asthma. Activating iNKT induces increasing IFN-γ, TGF-β, IL-2, and IL-10 potentially suppressing allergic asthma. However, their immunomodulatory effects, including granzyme-perforin-mediated cytotoxicity, and expression of TIM-3 and TRAIL warrant careful consideration and targeted approaches. Although CAR-T cell therapy has achieved remarkable success in treating certain cancers, its limitations necessitate exploring alternative approaches. In this context, CAR-NKT cells emerge as a promising approach for overcoming these challenges, potentially achieving safer and more effective immunotherapies. Strategies involve targeting distinct IgE-receptors and their interactions with CAR-NKT cells, potentially disrupting allergen-mast cell/basophil interactions and preventing inflammatory cytokine release. Additionally, targeting immune checkpoints like PDL-2, inducible ICOS, FASL, CTLA-4, and CD137 or dectin-1 for fungal asthma could further modulate immune responses. Furthermore, artificial intelligence and machine learning hold immense promise for revolutionizing NKT cell-based asthma therapy. AI can optimize CAR-NKT cell functionalities, design personalized treatment strategies, and unlock a future of precise and effective care. This review discusses various approaches to enhancing CAR-NKT cell efficacy and longevity, along with the challenges and opportunities they present in the treatment of allergic asthma.

Extracellular vesicles-powered immunotherapy: Unleashing the potential for safer and more effective cancer treatment

Cancer treatment has seen significant advancements with the introduction of Onco-immunotherapies (OIMTs). Although some of these therapies have received approval for use, others are either undergoing testing or are still in the early stages of development. Challenges persist in making immunotherapy widely applicable to cancer treatment. To maximize the benefits of immunotherapy and minimize potential side effects, it's essential to improve response rates across different immunotherapy methods. A promising development in this area is the use of extracellular vesicles (EVs) as novel delivery systems. These small vesicles can effectively deliver immunotherapies, enhancing their effectiveness and reducing harmful side effects. This article discusses the importance of integrating nanomedicines into OIMTs, highlighting the challenges with current anti-OIMT methods. It also explores key considerations for designing nanomedicines tailored for OIMTs, aiming to improve upon existing immunotherapy techniques. Additionally, the article looks into innovative approaches like biomimicry and the use of natural biomaterial-based nanocarriers (NCs). These advancements have the potential to transform the delivery of immunotherapy. Lastly, the article addresses the challenges of moving OIMTs from theory to clinical practice, providing insights into the future of using advanced nanotechnology in cancer treatment.

Deleting the mitochondrial respiration negative regulator MCJ enhances the efficacy of CD8+ T cell adoptive therapies in pre-clinical studies

Mitochondrial respiration is essential for the survival and function of T cells used in adoptive cellular therapies. However, strategies that specifically enhance mitochondrial respiration to promote T cell function remain limited. Here, we investigate methylation-controlled J protein (MCJ), an endogenous negative regulator of mitochondrial complex I expressed in CD8 cells, as a target for improving the efficacy of adoptive T cell therapies. We demonstrate that MCJ inhibits mitochondrial respiration in murine CD8+ CAR-T cells and that deletion of MCJ increases their in vitro and in vivo efficacy against murine B cell leukaemia. Similarly, MCJ deletion in ovalbumin (OVA)-specific CD8+ T cells also increases their efficacy against established OVA-expressing melanoma tumors in vivo. Furthermore, we show for the first time that MCJ is expressed in human CD8 cells and that the level of MCJ expression correlates with the functional activity of CD8+ CAR-T cells. Silencing MCJ expression in human CD8 CAR-T cells increases their mitochondrial metabolism and enhances their anti-tumor activity. Thus, targeting MCJ may represent a potential therapeutic strategy to increase mitochondrial metabolism and improve the efficacy of adoptive T cell therapies.

CAR-T Cell Therapy in Ovarian Cancer: Where Are We Now?

The success of chimeric antigen receptor T-cell (CAR-T) therapies in the treatment of hematologic malignancies has led to the investigation of their potential in the treatment of solid tumors, including ovarian cancer. While the immunosuppressive microenvironment of ovarian cancer has been a barrier in their implementation, several early phase clinical trials are currently evaluating CAR-T cell therapies targeting mesothelin, folate receptor a, HER2, MUC16, and B7H3. Ongoing challenges include cytokine-associated and "on-target, off-tumor" toxicities, while most common adverse events include cytokine release syndrome, hemophagocytic lymphohistiocytosis/macrophage activation-like syndrome (HLH/MAS), and neurotoxicity. In the present review, we summarize the current status of CAR-T therapy in ovarian cancer and discuss future directions.

Tumor immune evasion: insights from CRISPR screens and future directions

Despite the clinical success of cancer immunotherapies including immune checkpoint blockade and adoptive cellular therapies across a variety of cancer types, many patients do not respond or ultimately relapse; however, the molecular underpinnings of this are not fully understood. Thus, a system-level understating of the routes to tumor immune evasion is required to inform the design of the next generation of immunotherapy approaches. CRISPR screening approaches have proved extremely powerful in identifying genes that promote tumor immune evasion or sensitize tumor cells to destruction by the immune system. These large-scale efforts have brought to light decades worth of fundamental immunology and have uncovered the key immune-evasion pathways subverted in cancers in an acquired manner in patients receiving immune-modulatory therapies. The comprehensive discovery of the main pathways involved in immune evasion has spurred the development and application of novel immune therapies to target this process. Although successful, conventional CRISPR screening approaches are hampered by a number of limitations, which obfuscate a complete understanding of the precise molecular regulation of immune evasion in cancer. Here, we provide a perspective on screening approaches to interrogate tumor-lymphocyte interactions and their limitations, and discuss further development of technologies to improve such approaches and discovery capability.

Generation of antigen-specific mature T cells from RAG1-/-RAG2-/-B2M-/- stem cells by engineering their microenvironment

Pluripotent stem cells (PSCs) are a promising source of allogeneic T cells for off-the-shelf immunotherapies. However, the process of differentiating genetically engineered PSCs to generate mature T cells requires that the same molecular elements that are crucial for the selection of these cells be removed to prevent alloreactivity. Here we show that antigen-restricted mature T cells can be generated in vitro from PSCs edited via CRISPR to lack endogenous T cell receptors (TCRs) and class I major histocompatibility complexes. Specifically, we used T cell precursors from RAG1-/-RAG2-/-B2M-/- human PSCs expressing a single TCR, and a murine stromal cell line providing the cognate human major histocompatibility complex molecule and other critical signals for T cell maturation. Possibly owing to the absence of TCR mispairing, the generated T cells showed substantially better tumour control in mice than T cells with an intact endogenous TCR. Introducing the T cell selection components into the stromal microenvironment of the PSCs overcomes inherent biological challenges associated with the development of T cell immunotherapies from allogeneic PSCs.

In Situ Reprogramming of Immune Cells Using Synthetic Nanomaterials

In the past decade, adoptive cell therapy with chimeric antigen receptor-T (CAR-T) cells has revolutionized cancer treatment. However, the complexity and high costs involved in manufacturing current adoptive cell therapy greatly inhibit its widespread availability and access. To address this, in situ cell therapy, which directly reprograms immune cells inside the body, has recently been developed as a promising alternative. Here, an overview of the recent progress in the development of synthetic nanomaterials is provided to deliver plasmid DNA or mRNA for in situ reprogramming of T cells and macrophages, focusing especially on in situ CAR therapies. Also, the main challenges for in situ immune cell reprogramming are discussed and some approaches to overcome these barriers to fulfill the clinical applications are proposed.

Boosting immune responses in lung tumor immune microenvironment: A comprehensive review of strategies and adjuvants

The immune system has a substantial impact on the growth and expansion of lung malignancies. Immune cells are encompassed by a stroma comprising an extracellular matrix (ECM) and different cells like stromal cells, which are known as the tumor immune microenvironment (TIME). TME is marked by the presence of immunosuppressive factors, which inhibit the function of immune cells and expand tumor growth. In recent years, numerous strategies and adjuvants have been developed to extend immune responses in the TIME, to improve the efficacy of immunotherapy. In this comprehensive review, we outline the present knowledge of immune evasion mechanisms in lung TIME, explain the biology of immune cells and diverse effectors on these components, and discuss various approaches for overcoming suppressive barriers. We highlight the potential of novel adjuvants, including toll-like receptor (TLR) agonists, cytokines, phytochemicals, nanocarriers, and oncolytic viruses, for enhancing immune responses in the TME. Ultimately, we provide a summary of ongoing clinical trials investigating these strategies and adjuvants in lung cancer patients. This review also provides a broad overview of the current state-of-the-art in boosting immune responses in the TIME and highlights the potential of these approaches for improving outcomes in lung cancer patients.

Human CD4+CD25+ T cells expressing a chimeric antigen receptor against aberrant superoxide dismutase 1 trigger antigen-specific immunomodulation

BACKGROUND AIMS

Amyotrophic lateral sclerosis (ALS) is a fatal disease associated with motor neuron degeneration, accumulation of aggregated misfolded proteins and neuroinflammation in motor regions of the central nervous system (CNS). Clinical trials using regulatory T cells (Tregs) are ongoing because of Tregs' immunomodulatory function, ability to traffic to the CNS, high numbers correlating with slower disease in ALS and disease-modifying activity in ALS mouse models. In the current study, a chimeric antigen receptor (CAR) was developed and characterized in human Tregs to enhance their immunomodulatory activity when in contact with an ALS protein aggregate.

METHODS

A CAR (DG05-28-3z) consisting of a human superoxide dismutase 1 (hSOD1)-binding single-chain variable fragment, CD28 hinge, transmembrane and co-stimulatory domain and CD3ζ signaling domain was created and expressed in human Tregs. Human Tregs were isolated by either magnetic enrichment for CD4+CD25hi cells (Enr-Tregs) or cell sorting for CD4+CD25hiCD127lo cells (FP-Tregs), transduced and expanded for 17 days.

RESULTS

The CAR bound preferentially to the ALS mutant G93A-hSOD1 protein relative to the wild-type hSOD1 protein. The CAR Tregs produced IL-10 when cultured with aggregated G93A-hSOD1 proteins or spinal cord explants from G93A-hSOD1 transgenic mice. Co-culturing DG05-28-3z CAR Tregs with human monocytes/macrophages inhibited production of tumor necrosis factor alpha and reactive oxygen species. Expanded FP-Tregs resulted in more robust Tregs compared with Enr-Tregs. FP-Tregs produced similar IL-10 and less interferon gamma, had lower Treg-specific demethylated region methylation and expressed higher FoxP3 and CD39.

CONCLUSIONS

Taken together, this study demonstrates that gene-modified Tregs can be developed to target an aggregated ALS-relevant protein to elicit CAR-mediated Treg effector functions and provides an approach for generating Treg therapies for ALS with the goal of enhanced disease site-specific immunomodulation.

Transposon-Based Manufacturing of Human CAR-T Cells

In this chapter, the methodologies are outlined for generating CAR-T from PBMCs using transposon engineering. Additionally, some methods and guidance related to basic functional and phenotypic analysis are described. This methodology can be applied to manufacture and assess chimeric antigen receptors for preclinical applications targeting a variety of molecules.

Nanosensor Chemical Cytometry: Advances and Opportunities in Cellular Therapy and Precision Medicine

With the definition of therapeutics now encompassing transplanted or engineered cells and their molecular products, there is a growing scientific necessity for analytics to understand this new category of drugs. This Perspective highlights the recent development of new measurement science on label-free single cell analysis, nanosensor chemical cytometry (NCC), and their potential for cellular therapeutics and precision medicine. NCC is based on microfluidics integrated with fluorescent nanosensor arrays utilizing the optical lensing effect of a single cell to real-time extract molecular properties and correlate them with physical attributes of single cells. This new class of cytometry can quantify the heterogeneity of the multivariate physicochemical attributes of the cell populations in a completely label-free and nondestructive way and, thus, suggest the vein-to-vein conditions for the safe therapeutic applications. After the introduction of the NCC technology, we suggest the technological development roadmap for the maturation of the new field: from the sensor/chip design perspective to the system/software development level based on hardware automation and deep learning data analytics. The advancement of this new single cell sensing technology is anticipated to aid rich and multivariate single cell data setting and support safe and reliable cellular therapeutics. This new measurement science can lead to data-driven personalized precision medicine.

Natural killer cells for pancreatic cancer immunotherapy: Role of nanoparticles

Advanced pancreatic cancer patients have a dismal prognosis despite advances in integrative therapy. The field of tumor immunology has witnessed significant advancements for cancer treatment. However, immunotherapy for pancreatic cancer is not very effective due to its highly complex tumor microenvironment (TME). Natural killer (NK) cells are lymphocytes that play an important role in the innate immune system. NK cells do not require antigen pre-sensitization, nor are they confined by the major histocompatibility complex (MHC). NK cells have the potential to eliminate cancer cells through CAR-dependent and CAR-independent pathways, demonstrating reduced levels of systemic toxicity in the process. The availability of several potential sources of NK cells is an additional benefit that contributes to meeting the therapeutic criteria. Adding nanotechnology to enhance the functions of effector NK cells is also an appealing strategy. This article primarily discusses various approaches recently been utilized to enhance the NK functions for the treatment of pancreatic cancer. In addition, new advances in boosting NK cell therapeutic efficacy by nanoparticle mediation are presented, with a focus on pancreatic cancer.

Considerations and Approaches for Cancer Immunotherapy in the Aging Host

Advances in cancer immunotherapy are improving treatment successes in many distinct cancer types. Nonetheless, most tumors fail to respond. Age is the biggest risk for most cancers, and the median population age is rising worldwide. Advancing age is associated with manifold alterations in immune cell types, abundance, and functions, rather than simple declines in these metrics, the consequences of which remain incompletely defined. Our understanding of the effects of host age on immunotherapy mechanisms, efficacy, and adverse events remains incomplete. A deeper understanding of age effects in all these areas is required. Most cancer immunotherapy preclinical studies examine young subjects and fail to assess age contributions, a remarkable deficit given the known importance of age effects on immune cells and factors mediating cancer immune surveillance and immunotherapy efficacy. Notably, some cancer immunotherapies are more effective in aged versus young hosts, while others fail despite efficacy in the young. Here, we review our current understanding of age effects on immunity and associated nonimmune cells, the tumor microenvironment, cancer immunotherapy, and related adverse effects. We highlight important knowledge gaps and suggest areas for deeper enquiries, including in cancer immune surveillance, treatment response, adverse event outcomes, and their mitigation.

Understanding cervical cancer at single-cell resolution

Cervical cancer is now the fourth most prevalent malignancy in women worldwide, representing a tremendous burden of cancer. The heterogeneity of complex tumor ecosystem impacts tumorigenesis, malignant progression, and response to treatment; thus, a thorough understanding of the tumor ecosystem is vital for enhancing the prognosis of patients with cervical cancer. The rapid development and widespread use of single-cell sequencing have generated a new paradigm of cancer research, providing a comprehensive and in-depth understanding of cancers. In this review, we give an overview of the recent advances made by leveraging single-cell sequencing studies in the dissection of cervical cancer ecosystem heterogeneity. We highlight the evolution of the cervical cancer ecosystem during tumor initiation, progression, and treatment. High-resolution dissection of cervical cancer at the single-cell level has the potential to drive the development of targeted therapies and enable the realization of personalized medicine.

Engineering CAR-NK cell derived exosome disguised nano-bombs for enhanced HER2 positive breast cancer brain metastasis therapy

HER2-positive breast cancer brain metastasis (HER2+ BCBM) is a refractory malignancy with a high recurrence rate and poor prognosis. The efficacies of conventional treatments, including radiation and the FDA-approved drug trastuzumab, are compromised due to their significant obstacles, such as limited penetration through the blood-brain barrier (BBB), off-target effects on HER2+ tumor cells, and systemic adverse reactions, ultimately resulting in suboptimal therapeutic outcomes. In order to address these challenges, a novel biomimetic nanoplatform was created, which consisted of a combination of chimeric antigen receptor-natural killer (CAR-NK) cell-derived exosomes (ExoCAR), and a nanobomb (referred to as Micelle). This nanoplatform, known as ExoCAR/T7@Micelle, was designed to enhance the effectiveness of antitumor treatment by disrupting ferroptosis defense mechanisms. Due to the transferrin receptor binding peptide (T7) modification and CAR expression on the exosome surface, the nanoplatform successfully traversed the blood-brain barrier and selectively targeted HER2+ breast cancer cells. Moreover, integration of the reactive oxygen species (ROS) -amplified and photodynamic therapy (PDT)-based nanobomb facilitated the spatiotemporal release of the cargos at specific sites. Upon systemic administration of ExoCAR/T7@Micelle, mice with orthotopic HER2+ BCBM demonstrated a robust antitumor response in vivo, leading to a significant extension in survival time. Furthermore, histological analyses and blood index studies revealed no discernible side effects. Collectively, this study is the first to indicate the possibility of HER2+ BCBM therapy with a CAR-NK cell-derived biomimetic drug delivery system.

Generation of functionally distinct T-cell populations by altering the viscoelasticity of their extracellular matrix

The efficacy of adoptive T-cell therapies largely depends on the generation of T-cell populations that provide rapid effector function and long-term protective immunity. Yet it is becoming clearer that the phenotypes and functions of T cells are inherently linked to their localization in tissues. Here we show that functionally distinct T-cell populations can be generated from T cells that received the same stimulation by altering the viscoelasticity of their surrounding extracellular matrix (ECM). By using a model ECM based on a norbornene-modified collagen type I whose viscoelasticity can be adjusted independently from its bulk stiffness by varying the degree of covalent crosslinking via a bioorthogonal click reaction with tetrazine moieties, we show that ECM viscoelasticity regulates T-cell phenotype and function via the activator-protein-1 signalling pathway, a critical regulator of T-cell activation and fate. Our observations are consistent with the tissue-dependent gene-expression profiles of T cells isolated from mechanically distinct tissues from patients with cancer or fibrosis, and suggest that matrix viscoelasticity could be leveraged when generating T-cell products for therapeutic applications.

Learning from the microbes: exploiting the microbiome to enforce T cell immunotherapy

The opportunities genetic engineering has created in the field of adoptive cellular therapy for cancer are accelerating the development of novel treatment strategies using chimeric antigen receptor (CAR) and T cell receptor (TCR) T cells. The great success in the context of hematologic malignancies has made especially CAR T cell therapy a promising approach capable of achieving long-lasting remission. However, the causalities involved in mediating resistance to treatment or relapse are still barely investigated. Research on T cell exhaustion and dysfunction has drawn attention to host-derived factors that define both the immune and tumor microenvironment (TME) crucially influencing efficacy and toxicity of cellular immunotherapy. The microbiome, as one of the most complex host factors, has become a central topic of investigations due to its ability to impact on health and disease. Recent findings support the hypothesis that commensal bacteria and particularly microbiota-derived metabolites educate and modulate host immunity and TME, thereby contributing to the response to cancer immunotherapy. Hence, the composition of microbial strains as well as their soluble messengers are considered to have predictive value regarding CAR T cell efficacy and toxicity. The diversity of mechanisms underlying both beneficial and detrimental effects of microbiota comprise various epigenetic, metabolic and signaling-related pathways that have the potential to be exploited for the improvement of CAR T cell function. In this review, we will discuss the recent findings in the field of microbiome-cancer interaction, especially with respect to new trajectories that commensal factors can offer to advance cellular immunotherapy.

Lipid metabolic reprogramming in tumor microenvironment: from mechanisms to therapeutics

Lipid metabolic reprogramming is an emerging hallmark of cancer. In order to sustain uncontrolled proliferation and survive in unfavorable environments that lack oxygen and nutrients, tumor cells undergo metabolic transformations to exploit various ways of acquiring lipid and increasing lipid oxidation. In addition, stromal cells and immune cells in the tumor microenvironment also undergo lipid metabolic reprogramming, which further affects tumor functional phenotypes and immune responses. Given that lipid metabolism plays a critical role in supporting cancer progression and remodeling the tumor microenvironment, targeting the lipid metabolism pathway could provide a novel approach to cancer treatment. This review seeks to: (1) clarify the overall landscape and mechanisms of lipid metabolic reprogramming in cancer, (2) summarize the lipid metabolic landscapes within stromal cells and immune cells in the tumor microenvironment, and clarify their roles in tumor progression, and (3) summarize potential therapeutic targets for lipid metabolism, and highlight the potential for combining such approaches with other anti-tumor therapies to provide new therapeutic opportunities for cancer patients.

Chimeric antigen receptor engineered natural killer cells for cancer therapy

Natural killer (NK) cells, a unique component of the innate immune system, are inherent killers of stressed and transformed cells. Based on their potent capacity to kill cancer cells and good tolerance of healthy cells, NK cells have been successfully employed in adoptive cell therapy to treat cancer patients. In recent years, the clinical success of chimeric antigen receptor (CAR)-T cells has proven the vast potential of gene-manipulated immune cells as the main force to fight cancer. Following the lessons learned from mature gene-transfer technologies and advanced strategies in CAR-T therapy, NK cells have been rapidly explored as a promising candidate for CAR-based therapy. An exponentially growing number of studies have employed multiple sources of CAR-NK cells to target a wide range of cancer-related antigens, showing remarkable outcomes and encouraging safety profiles. Clinical trials of CAR-NK cells have also shown their impressive therapeutic efficacy in the treatment of hematological tumors, but CAR-NK cell therapy for solid tumors is still in the initial stages. In this review, we present the favorable profile of NK cells as a potential platform for CAR-based engineering and then summarize the outcomes and strategies of CAR-NK therapies in up-to-date preclinical and clinical investigations. Finally, we evaluate the challenges remaining in CAR-NK therapy and describe existing strategies that can assist us in devising future prospective solutions.

Adoptive T cell transfer and host antigen-presenting cell recruitment with cryogel scaffolds promotes long-term protection against solid tumors

Although adoptive T cell therapy provides the T cell pool needed for immediate tumor debulking, the infused T cells generally have a narrow repertoire for antigen recognition and limited ability for long-term protection. Here, we present a hydrogel that locally delivers adoptively transferred T cells to the tumor site while recruiting and activating host antigen-presenting cells with GMCSF or FLT3L and CpG, respectively. T cells alone loaded into these localized cell depots provided significantly better control of subcutaneous B16-F10 tumors than T cells delivered through direct peritumoral injection or intravenous infusion. T cell delivery combined with biomaterial-driven accumulation and activation of host immune cells prolonged the activation of the delivered T cells, minimized host T cell exhaustion, and enabled long-term tumor control. These findings highlight how this integrated approach provide both immediate tumor debulking and long-term protection against solid tumors, including against tumor antigen escape.

Capturing the Impact of Constraints on the Cost-Effectiveness of Cell and Gene Therapies: A Systematic Review

OBJECTIVE

Decision-makers need to resolve constraints on delivering cell and gene therapies to patients as these treatments move into routine care. This study aimed to investigate if, and how, constraints that affect the expected cost and health consequences of cell and gene therapies have been included in published examples of cost-effectiveness analyses (CEAs).

METHOD

A systematic review identified CEAs of cell and gene therapies. Studies were identified from previous systematic reviews and by searching Medline and Embase until 21 January 2022. Constraints described qualitatively were categorised by theme and summarised by a narrative synthesis. Constraints evaluated in quantitative scenario analyses were appraised by whether they changed the decision to recommend treatment.

RESULTS

Thirty-two CEAs of cell (n = 20) and gene therapies (n = 12) were included. Twenty-one studies described constraints qualitatively (70% cell therapy CEAs; 58% gene therapy CEAs). Qualitative constraints were categorised by four themes: single payment models; long-term affordability; delivery by providers; manufacturing capability. Thirteen studies assessed constraints quantitatively (60% cell therapy CEAs; 8% gene therapy CEAs). Two types of constraint were assessed quantitatively across four jurisdictions (USA, Canada, Singapore, The Netherlands): alternatives to single payment models (n = 9 scenario analyses); improving manufacturing (n = 12 scenario analyses). The impact on decision-making was determined by whether the estimated incremental cost-effectiveness ratios crossed a relevant cost-effectiveness threshold for each jurisdiction (outcome-based payment models: n = 25 threshold comparisons made, 28% decisions changed; improving manufacturing: n = 24 threshold comparisons made, 4% decisions changed).

CONCLUSION

The net health impact of constraints is vital evidence to help decision-makers scale up the delivery of cell and gene therapies as patient volume increases and more advanced therapy medicinal products are launched. CEAs will be essential to quantify how constraints affect the cost-effectiveness of care, prioritise constraints to be resolved, and establish the value of strategies to implement cell and gene therapies by accounting for their health opportunity cost.

A non-genetic engineering platform for rapidly generating and expanding cancer-specific armed T cells

BACKGROUND

Cancer-specific adoptive T cell therapy has achieved successful milestones in multiple clinical treatments. However, the commercial production of cancer-specific T cells is often hampered by laborious cell culture procedures, the concern of retrovirus-based gene transfection, or insufficient T cell purity.

METHODS

In this study, we developed a non-genetic engineering technology for rapidly manufacturing a large amount of cancer-specific T cells by utilizing a unique anti-cancer/anti-CD3 bispecific antibody (BsAb) to directly culture human peripheral blood mononuclear cells (PBMCs). The anti-CD3 moiety of the BsAb bound to the T cell surface and stimulated the differentiation and proliferation of T cells in PBMCs. The anti-cancer moiety of the BsAb provided these BsAb-armed T cells with the cancer-targeting ability, which transformed the naïve T cells into cancer-specific BsAb-armed T cells.

RESULTS

With this technology, a large amount of cancer-specific BsAb-armed T cells can be rapidly generated with a purity of over 90% in 7 days. These BsAb-armed T cells efficiently accumulated at the tumor site both in vitro and in vivo. Cytotoxins (perforin and granzyme) and cytokines (TNF-α and IFN-γ) were dramatically released from the BsAb-armed T cells after engaging cancer cells, resulting in a remarkable anti-cancer efficacy. Notably, the BsAb-armed T cells did not cause obvious cytokine release syndrome or tissue toxicity in SCID mice bearing human tumors.

CONCLUSIONS

Collectively, the BsAb-armed T cell technology represents a simple, time-saving, and highly safe method to generate highly pure cancer-specific effector T cells, thereby providing an affordable T cell immunotherapy to patients.

Single CAR-T cell treatment controls disseminated ovarian cancer in a syngeneic mouse model

BACKGROUND

Treatment of some blood cancers with T cells that express a chimeric antigen receptor (CAR) against CD19 have shown remarkable results. In contrast, CAR-T cell efficacy against solid tumors has been difficult to achieve.

METHODS

To examine the potential of CAR-T cell treatments against ovarian cancers, we used the mouse ovarian cancer cell line ID8 in an intraperitoneal model that exhibits disseminated solid tumors in female C57BL/6J mice. The CAR contained a single-chain Fv from antibody 237 which recognizes a Tn-glycopeptide-antigen expressed by ID8 due to aberrant O-linked glycosylation in the absence of the transferase-dependent chaperone Cosmc. The efficacy of four Tn-dependent CARs with varying affinity to Tn antigen, and each containing CD28/CD3ζ cytoplasmic domains, were compared in vitro and in vivo in this study.

RESULTS

In line with many observations about the impact of aberrant O-linked glycosylation, the ID8Cosmc knock-out (ID8Cosmc-KO) exhibited more rapid tumor progression compared with wild-type ID8. Despite the enhanced tumor growth in vivo, 237 CAR and a mutant with 30-fold higher affinity, but not CARs with lower affinity, controlled advanced ID8Cosmc-KO tumors. Tumor regression could be achieved with a single intravenous dose of the CARs, but intraperitoneal administration was even more effective. The CAR-T cells persisted over a period of months, allowing CAR-treated mice to delay tumor growth in a re-challenge setting. The most effective CARs exhibited the highest affinity for antigen. Antitumor effects observed in vivo were associated with increased numbers of T cells and macrophages, and higher levels of cleaved caspase-3, in the tumor microenvironment. Notably, the least therapeutically effective CAR mediated tonic signaling leading to antigen-independent cytokine expression and it had higher levels of the immunosuppressive cytokine interleukin10.

CONCLUSION

The findings support the development of affinity-optimized CAR-T cells as a potential treatment for established ovarian cancer, with the most effective CARs mediating a distinct pattern of inflammatory cytokine release in vitro. Importantly, the most potent Tn-dependent CAR-T cells showed no evidence of toxicity in tumor-bearing mice in a syngeneic, immunocompetent system.

Orthogonal cytokine engineering enables novel synthetic effector states escaping canonical exhaustion in tumor-rejecting CD8+ T cells

To date, no immunotherapy approaches have managed to fully overcome T-cell exhaustion, which remains a mandatory fate for chronically activated effector cells and a major therapeutic challenge. Understanding how to reprogram CD8+ tumor-infiltrating lymphocytes away from exhausted effector states remains an elusive goal. Our work provides evidence that orthogonal gene engineering of T cells to secrete an interleukin (IL)-2 variant binding the IL-2Rβγ receptor and the alarmin IL-33 reprogrammed adoptively transferred T cells to acquire a novel, synthetic effector state, which deviated from canonical exhaustion and displayed superior effector functions. These cells successfully overcame homeostatic barriers in the host and led-in the absence of lymphodepletion or exogenous cytokine support-to high levels of engraftment and tumor regression. Our work unlocks a new opportunity of rationally engineering synthetic CD8+ T-cell states endowed with the ability to avoid exhaustion and control advanced solid tumors.

Harnessing sortase A transpeptidation for advanced targeted therapeutics and vaccine engineering

The engineering of potent prophylactic and therapeutic complexes has always required careful protein modification techniques with seamless capabilities. In this light, methods that favor unobstructed multivalent targeting and correct antigen presentations remain essential and very demanding. Sortase A (SrtA) transpeptidation has exhibited these attributes in various settings over the years. However, its applications for engineering avidity-inspired therapeutics and potent vaccines have yet to be significantly noticed, especially in this era where active targeting and multivalent nanomedications are in great demand. This review briefly presents the SrtA enzyme and its associated transpeptidation activity and describes interesting sortase-mediated protein engineering and chemistry approaches for achieving multivalent therapeutic and antigenic responses. The review further highlights advanced applications in targeted delivery systems, multivalent therapeutics, adoptive cellular therapy, and vaccine engineering. These innovations show the potential of sortase-mediated techniques in facilitating the development of simple plug-and-play nanomedicine technologies against recalcitrant diseases and pandemics such as cancer and viral infections.

Engineering second-generation TCR-T cells by site-specific integration of TRAF-binding motifs into the CD247 locus

BACKGROUND

The incorporation of co-stimulatory signaling domains into second-generation chimeric antigen receptors (CARs) significantly enhances the proliferation and persistence of CAR-T cells in vivo, leading to successful clinical outcomes.

METHODS

To achieve such functional enhancement in transgenic T-cell receptor-engineered T-cell (TCR-T) therapy, we designed a second-generation TCR-T cell in which CD3ζ genes modified to contain the intracellular domain (ICD) of the 4-1BB receptor were selectively inserted into the CD247 locus.

RESULTS

This modification enabled the simultaneous recruitment of key adaptor molecules for signals 1 and 2 on TCR engagement. However, the addition of full-length 4-1BB ICD unexpectedly impaired the expression and signaling of TCRs, leading to suboptimal antitumor activity of the resulting TCR-T cells in vivo. We found that the basic-rich motif (BRM) in the 4-1BB ICD was responsible for the undesirable outcomes, and that fusion of minimal tumor necrosis factor receptor-associated factor (TRAF)-binding motifs at the C-terminus of CD3ζ (zBB^ΔBRM) was sufficient to recruit TRAF2, the key adaptor molecule in 4-1BB signaling, while retaining the expression and proximal signaling of the transgenic TCR. Consequently, TCR-T cells expressing zBB^ΔBRM exhibited improved persistence and expansion in vitro and in vivo, resulting in superior antitumor activity in a mouse xenograft model.

CONCLUSIONS

Our findings offer a promising strategy for improving the intracellular signaling of TCR-T cells and their application in treating solid tumors.

CARs: a new approach for the treatment of autoimmune diseases

The development of chimeric antigen receptor (CAR)-based therapeutic interventions represented a breakthrough in cancer treatment. Following the success of the CAR-T-cell strategy, this novel therapeutic approach has been applied to other diseases, including autoimmune diseases. Using CAR-T cells to deplete pathological immune cells (i.e., B cells, autoreactive B or T cells, and accessory antigen-presenting cells (APCs)) has resulted in favorable outcomes in diseases characterized by excessive autoantibody levels or hyperactive lymphocyte cell numbers. The importance of immunosuppressive regulatory T cells (Tregs) in restoring immune tolerance has been well established, and CAR-Tregs have shown promising therapeutic potential in treating autoimmune diseases. Moreover, prior experience from the cancer field has provided sufficient paradigms for understanding how to optimize the structure and function of CARs to improve their function, persistence, stability and safety. In this review, we describe the potential application of CAR-T cells and CAR-Tregs in the treatment of autoimmune diseases, and we summarize the currently available strategies of gene editing and synthetic biological tools that have improved the practical application of CAR-based therapies.

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.

Immunotherapeutics in lung cancers: from mechanistic insight to clinical implications and synergistic perspectives

BACKGROUND

Lung cancer is one of the highly lethal forms of cancer whose incidence has worldwide rapidly increased over the past few decades. About 80-85% of all lung cancer cases constitute non-small cell lung cancer (NSCLC), with adenocarcinoma, squamous cell carcinoma and large cell carcinoma as the main subtypes. Immune checkpoint inhibitors have led to significant advances in the treatment of a variety of solid tumors, significantly improving cancer patient survival rates.

METHODS AND RESULTS

The cytotoxic drugs in combination with anti-PD-(L)1 antibodies is a new method that aims to reduce the activation of immunosuppressive and cancer cell prosurvival responses while also improving direct cancer cell death. The most commonly utilized immune checkpoint inhibitors for patients with non-small cell lung cancer are monoclonal antibodies (Atezolizumab, Cemiplimab, Ipilimumab, Pembrolizumab etc.) against PD-1, PD-L1, and CTLA-4. Among them, Atezolizumab (TECENTRIQ) and Cemiplimab (Libtayo) are engineered monoclonal anti programmed death ligand 1 (PD-L1) antibodies that inhibit binding of PD-L1 to PD-1 and B7.1. As a result, T-cell proliferation and cytokine synthesis are inhibited leading to restoring the immune homeostasis to fight cancer cells.

CONCLUSIONS

In this review article, the path leading to the introduction of immunotherapeutic options in lung cancer treatment is described, with analyzing the benefits and shortages of the current immunotherapeutic drugs. In addition, possibilities to co-administer immunotherapeutic agents with standard cancer treatment modalities are also considered.

Decoupling peptide binding from T cell receptor recognition with engineered chimeric MHC-I molecules

Major Histocompatibility Complex class I (MHC-I) molecules display self, viral or aberrant epitopic peptides to T cell receptors (TCRs), which employ interactions between complementarity-determining regions with both peptide and MHC-I heavy chain 'framework' residues to recognize specific Human Leucocyte Antigens (HLAs). The highly polymorphic nature of the HLA peptide-binding groove suggests a malleability of interactions within a common structural scaffold. Here, using structural data from peptide:MHC-I and pMHC:TCR structures, we first identify residues important for peptide and/or TCR binding. We then outline a fixed-backbone computational design approach for engineering synthetic molecules that combine peptide binding and TCR recognition surfaces from existing HLA allotypes. X-ray crystallography demonstrates that chimeric molecules bridging divergent HLA alleles can bind selected peptide antigens in a specified backbone conformation. Finally, in vitro tetramer staining and biophysical binding experiments using chimeric pMHC-I molecules presenting established antigens further demonstrate the requirement of TCR recognition on interactions with HLA framework residues, as opposed to interactions with peptide-centric Chimeric Antigen Receptors (CARs). Our results underscore a novel, structure-guided platform for developing synthetic HLA molecules with desired properties as screening probes for peptide-centric interactions with TCRs and other therapeutic modalities.

Tumor-Infiltrating Lymphocyte Therapy or Ipilimumab in Advanced Melanoma

BACKGROUND

Immune checkpoint inhibitors and targeted therapies have dramatically improved outcomes in patients with advanced melanoma, but approximately half these patients will not have a durable benefit. Phase 1-2 trials of adoptive cell therapy with tumor-infiltrating lymphocytes (TILs) have shown promising responses, but data from phase 3 trials are lacking to determine the role of TILs in treating advanced melanoma.

METHODS

In this phase 3, multicenter, open-label trial, we randomly assigned patients with unresectable stage IIIC or IV melanoma in a 1:1 ratio to receive TIL or anti-cytotoxic T-lymphocyte antigen 4 therapy (ipilimumab at 3 mg per kilogram of body weight). Infusion of at least 5×10⁹ TILs was preceded by nonmyeloablative, lymphodepleting chemotherapy (cyclophosphamide plus fludarabine) and followed by high-dose interleukin-2. The primary end point was progression-free survival.

RESULTS

A total of 168 patients (86% with disease refractory to anti-programmed death 1 treatment) were assigned to receive TILs (84 patients) or ipilimumab (84 patients). In the intention-to-treat population, median progression-free survival was 7.2 months (95% confidence interval [CI], 4.2 to 13.1) in the TIL group and 3.1 months (95% CI, 3.0 to 4.3) in the ipilimumab group (hazard ratio for progression or death, 0.50; 95% CI, 0.35 to 0.72; P<0.001); 49% (95% CI, 38 to 60) and 21% (95% CI, 13 to 32) of the patients, respectively, had an objective response. Median overall survival was 25.8 months (95% CI, 18.2 to not reached) in the TIL group and 18.9 months (95% CI, 13.8 to 32.6) in the ipilimumab group. Treatment-related adverse events of grade 3 or higher occurred in all patients who received TILs and in 57% of those who received ipilimumab; in the TIL group, these events were mainly chemotherapy-related myelosuppression.

CONCLUSIONS

In patients with advanced melanoma, progression-free survival was significantly longer among those who received TIL therapy than among those who received ipilimumab. (Funded by the Dutch Cancer Society and others; ClinicalTrials.gov number, NCT02278887.).

DNA origami-based artificial antigen-presenting cells for adoptive T cell therapy

Nanosized artificial antigen-presenting cells (aAPCs) with efficient signal presentation hold great promise for in vivo adoptive cell therapy. Here, we used DNA origami nanostructures as two-dimensional scaffolds to regulate the spatial presentation of activating ligands at nanoscale to construct high-effective aAPCs. The DNA origami-based aAPC comprises costimulatory ligands anti-CD28 antibody anchored at three vertices and T cell receptor (TCR) ligands peptide-major histocompatibility complex (pMHC) anchored at three edges with varying density. The DNA origami scaffold enables quantitative analysis of ligand-receptor interactions in T cell activation at the single-particle, single-molecule resolution. The pMHC-TCR-binding dwell time is increased from 9.9 to 12.1 s with increasing pMHC density, driving functional T cell responses. In addition, both in vitro and in vivo assays demonstrate that the optimized DNA origami-based aAPCs show effective tumor growth inhibiting capability in adoptive immunotherapy. These results provide important insights into the rational design of molecular vaccines for cancer immunotherapy.

Stem-like T cells and niches: Implications in human health and disease

Recently, accumulating evidence has elucidated the important role of T cells with stem-like characteristics in long-term maintenance of T cell responses and better patient outcomes after immunotherapy. The fate of TSL cells has been correlated with many physiological and pathological human processes. In this review, we described present advances demonstrating that stem-like T (TSL) cells are central players in human health and disease. We interpreted the evolutionary characteristics, mechanism and functions of TSL cells. Moreover, we discuss the import role of distinct niches and how they affect the stemness of TSL cells. Furthermore, we also outlined currently available strategies to generate TSL cells and associated affecting factors. Moreover, we summarized implication of TSL cells in therapies in two areas: stemness enhancement for vaccines, ICB, and adoptive T cell therapies, and stemness disruption for autoimmune disorders.