Engineering Strategies to Enhance TCR-Based Adoptive T Cell Therapy

Regulatory T cell-based therapy in type 1 diabetes: Latest breakthroughs and evidence

Autoimmune diseases (ADs) are among the most significant health complications, with their incidence rising in recent years. Type 1 diabetes (T1D), an AD, targets the insulin-producing β cells in the pancreas, leading to chronic insulin deficiency in genetically susceptible individuals. Regulatory immune cells, particularly T-cells (Tregs), have been shown to play a crucial role in the pathogenesis of diabetes by modulating immune responses. In diabetic patients, Tregs often exhibit diminished effectiveness due to various factors, such as instability in forkhead box P3 (Foxp3) expression or abnormal production of the proinflammatory cytokine interferon-gamma (IFN-γ) by autoreactive T-cells. Consequently, Tregs represent a potential therapeutic target for diabetes treatment. Building on the successful clinical outcomes of chimeric antigen receptor (CAR) T-cell therapy in cancer treatment, particularly in leukemias, the concept of designing and utilizing CAR Tregs for ADs has emerged. This review summarizes the findings on Treg targeting in T1D and discusses the benefits and limitations of this treatment approach for patients suffering from T1D.

Applications of single-cell analysis in immunotherapy for lung cancer: Current progress, new challenges and expectations

BACKGROUND

Lung cancer is a prevalent form of cancer worldwide, presenting a substantial risk to human well-being. Lung cancer is classified into two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). The advancement of tumor immunotherapy, specifically immune checkpoint inhibitors and adaptive T-cell therapy, has encountered substantial obstacles due to the rapid progression of SCLC and the metastasis, recurrence, and drug resistance of NSCLC. These challenges are believed to stem from the tumor heterogeneity of lung cancer within the tumor microenvironment.

AIM OF REVIEW

This review aims to comprehensively explore recent strides in single-cell analysis, a robust sequencing technology, concerning its application in the realm of tumor immunotherapy for lung cancer. It has been effectively integrated with transcriptomics, epigenomics, genomics, and proteomics for various applications. Specifically, these techniques have proven valuable in mapping the transcriptional activity of tumor-infiltrating lymphocytes in patients with NSCLC, identifying circulating tumor cells, and elucidating the heterogeneity of the tumor microenvironment.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The review emphasizes the paramount significance of single-cell analysis in mapping the immune cells within NSCLC patients, unveiling circulating tumor cells, and elucidating the tumor microenvironment heterogeneity. Notably, these advancements highlight the potential of single-cell analysis to revolutionize lung cancer immunotherapy by characterizing immune cell fates, improving therapeutic strategies, and identifying promising targets or prognostic biomarkers. It is potential to unravel the complexities within the tumor microenvironment and enhance treatment strategies marks a significant step towards more effective therapies and improved patient outcomes.

Clinical advances and challenges associated with TCR-T cell therapy for cancer treatment

Background

T cell receptor (TCR)-T cell therapy is an innovative form of cancer immunotherapy that genetically modifies patients' T cells to target and destroy cancer cells. However, the current status of clinical trials of TCR-T cell therapy for the treatment of cancer remains unclear. This study aimed to comprehensively analyze the registration trials related to TCR-T cell therapy for the treatment of cancer.

Methods

A comprehensive search was conducted in the Trialtrove database for all clinical trials related to TCR-T cell therapy registered by August 1, 2024. Inclusion criteria focused on trials targeting TCR-T cell therapy for oncology, and excluded observational studies and incomplete data. Statistical analysis was performed on key trial characteristics, with between-group comparisons utilizing chi-square or Fisher's exact tests.

Results

Analysis of 174 eligible clinical trials revealed that TCR-T cell therapy exhibits significant efficacy across various tumor types, particularly in refractory hematologic malignancies and certain solid tumors. Additionally, combining TCR-T cell therapy with other immunotherapies enhanced these anti-tumor effects.

Conclusion

TCR-T cell therapy holds substantial promise for cancer treatment. Future research should focus on optimizing treatment protocols, enhancing efficacy, and minimizing prices to fully realize the potential of this therapy.

The clinical applications of immunosequencing

Technological advances in high-throughput sequencing have opened the door for the interrogation of adaptive immune responses at unprecedented scale. It is now possible to determine the sequences of antibodies or T-cell receptors produced by individual B and T cells in a sample. This capability, termed immunosequencing, has transformed the study of both infectious and non-infectious diseases by allowing the tracking of dynamic changes in B and T cell clonal populations over time. This has improved our understanding of the pathology of cancers, autoimmune diseases, and infectious diseases. However, to date there has been only limited clinical adoption of the technology. Advances over the last decade and on the horizon that reduce costs and improve interpretability could enable widespread clinical use. Many clinical applications have been proposed and, while most are still undergoing research and development, some methods relying on immunosequencing data have been implemented, the most widespread of which is the detection of measurable residual disease. Here, we review the diagnostic, prognostic, and therapeutic applications of immunosequencing for both infectious and non-infectious diseases.

Harnessing the potential of hydrogels for advanced therapeutic applications: current achievements and future directions

The applications of hydrogels have expanded significantly due to their versatile, highly tunable properties and breakthroughs in biomaterial technologies. In this review, we cover the major achievements and the potential of hydrogels in therapeutic applications, focusing primarily on two areas: emerging cell-based therapies and promising non-cell therapeutic modalities. Within the context of cell therapy, we discuss the capacity of hydrogels to overcome the existing translational challenges faced by mainstream cell therapy paradigms, provide a detailed discussion on the advantages and principal design considerations of hydrogels for boosting the efficacy of cell therapy, as well as list specific examples of their applications in different disease scenarios. We then explore the potential of hydrogels in drug delivery, physical intervention therapies, and other non-cell therapeutic areas (e.g., bioadhesives, artificial tissues, and biosensors), emphasizing their utility beyond mere delivery vehicles. Additionally, we complement our discussion on the latest progress and challenges in the clinical application of hydrogels and outline future research directions, particularly in terms of integration with advanced biomanufacturing technologies. This review aims to present a comprehensive view and critical insights into the design and selection of hydrogels for both cell therapy and non-cell therapies, tailored to meet the therapeutic requirements of diverse diseases and situations.

An HLA-E-targeted TCR bispecific molecule redirects T cell immunity against Mycobacterium tuberculosis

Peptides presented by HLA-E, a molecule with very limited polymorphism, represent attractive targets for T cell receptor (TCR)-based immunotherapies to circumvent the limitations imposed by the high polymorphism of classical HLA genes in the human population. Here, we describe a TCR-based bispecific molecule that potently and selectively binds HLA-E in complex with a peptide encoded by the inhA gene of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis in humans. We reveal the biophysical and structural bases underpinning the potency and specificity of this molecule and demonstrate its ability to redirect polyclonal T cells to target HLA-E-expressing cells transduced with mycobacterial inhA as well as primary cells infected with virulent Mtb. Additionally, we demonstrate elimination of Mtb-infected cells and reduction of intracellular Mtb growth. Our study suggests an approach to enhance host T cell immunity against Mtb and provides proof of principle for an innovative TCR-based therapeutic strategy overcoming HLA polymorphism and therefore applicable to a broader patient population.

Development of Cell and Gene Therapies for Clinical Use in the US and EU: Summary of Regulatory Guidelines

Recent decades have seen advancements in the management and treatment of difficultto- treat diseases such as cancer. A special class of therapeutics called cell and gene therapy has been introduced in the past 10 years. Cell and gene therapy products have strengthened the treatment options for life-threatening diseases with unmet clinical needs and also provided the possibility of a potential cure for the disease in some of the patients. Cell and gene therapy products are gaining recognition, and the interest in clinical development of cell and gene therapy products is increasing. Moreover, as the class of cell and gene therapy products is relatively new, there is a limited regulatory experience in the development, and the developers of the cell and gene therapy products can often be puzzled with an array of questions on regulations. The current review intends to provide a basic understanding of regulatory guidelines from the FDA and EMA that are applicable to cell and gene therapy products. Essentials such as which office is responsible for the evaluation of applications, which regulatory class/pathway is appropriate for development, and what are the quality, nonclinical and clinical studies that are needed to support the application are discussed in the article. In addition, a summary of regulatory designations and the post-approval requirements, such as Risk Evaluation and Mitigation Strategies (REMS) and long-term follow- up, is included in the article. Developers (referred to as 'sponsors' in this article) of cell and gene therapies can use the respective guidance documents and other specific review articles cited in this review for detailed information on the topics.

Engineered Adoptive T-Cell Therapies for Breast Cancer: Current Progress, Challenges, and Potential

Breast cancer remains a significant health challenge, and novel treatment approaches are critically needed. This review presents an in-depth analysis of engineered adoptive T-cell therapies (E-ACTs), an innovative frontier in cancer immunotherapy, focusing on their application in breast cancer. We explore the evolving landscape of chimeric antigen receptor (CAR) and T-cell receptor (TCR) T-cell therapies, highlighting their potential and challenges in targeting breast cancer. The review addresses key obstacles such as target antigen selection, the complex breast cancer tumor microenvironment, and the persistence of engineered T-cells. We discuss the advances in overcoming these barriers, including strategies to enhance T-cell efficacy. Finally, our comprehensive analysis of the current clinical trials in this area provides insights into the future possibilities and directions of E-ACTs in breast cancer treatment.

Empowering gene delivery with protein engineering platforms

The repertoire of therapeutic proteins has been substantially augmented by molecular engineering approaches, which have seen remarkable advancement in recent years. In particular, advances in directed evolution technologies have empowered the development of custom-designed proteins with novel and disease-relevant functions. Whereas engineered proteins have typically been administered through systemic injection of the purified molecule, exciting progress in gene delivery affords the opportunity to elicit sustained production of the engineered proteins by targeted cells in the host organism. Combining developments at the leading edge of protein engineering and gene delivery has catapulted a new wave of molecular and cellular therapy approaches, which harbor great promise for personalized and precision medicine. This mini-review outlines currently used display platforms for protein evolution and describes recent examples of how the resulting engineered proteins have been incorporated into DNA- and cell-based therapeutic platforms, both in vitro and in vivo. Collectively, the strategies detailed herein provide a framework for synthesizing molecular engineering workflows with gene therapy systems for a breadth of applications in research and medicine.

Implications of Immunotherapy for Pediatric Malignancies: A Summary from the APSA Cancer Committee

Although survival for many pediatric cancers has improved with advances in conventional chemotherapeutic regimens and surgical techniques in the last several decades, it remains a leading cause of disease-related death in children. Outcomes in patients with recurrent, refractory, or metastatic disease are especially poor. Recently, the advent of alternative classes of therapies, including immunotherapies, have revolutionized systemic treatment for pediatric malignancies. Several classes of immunotherapies, including chimeric antigen receptor (CAR) T cell therapy, transgenic T-cell receptor (TCR)-T cell therapy, bispecific T-cell engagers, and monoclonal antibody checkpoint inhibitors have been FDA-approved or entered early-phase clinical trials in children and young adults. The pediatric surgeon is likely to encounter these therapies during the care of children with malignancies and should be familiar with the classes of therapy, indications, adverse events, and potential need for surgical intervention in these cases. This review from the APSA Cancer Committee offers a brief discussion of the three most encountered classes of immunotherapy in children and young adults and discusses surgical relevance. LEVEL OF EVIDENCE: IV.

A novel portable immuno-device for the recognition of lymphatic vessel endothelial hyaluronan receptor-1 biomarker using GQD-AgNPrs conductive ink stabilized on the surface of cellulose

Lymphatic vessel endothelium expresses various lymphatic marker molecules. LYVE-1, the lymphatic vessel endothelial hyaluronan (HA) receptor, a 322-residue protein belonging to the integral membrane glycoproteins which is found on lymph vessel wall and is completely absent from blood vessels. LYVE-1 is very effective in the passage of lymphocytes and tumor cells into the lymphatics. As regards cancer metastasis, in vitro studies indicate LYVE-1 to be involved in tumor cell adhesion. Researches show that, in neoplastic tissue, LYVE-1 is limited to the lymphovascular and could well be proper for studies of tumor lymphangiogenesis. So, the monitoring of LYVE-1 level in human biofluids has provided a valuable approach for research into tumor lymphangiogenesis. For the first time, an innovative paper-based electrochemical immune-platform was developed for recognition of LYVE-1. For this purpose, graphene quantum dots decorated silver nanoparticles nano-ink was synthesized and designed directly by writing pen-on paper technology on the surface of photographic paper. This nano-ink has a great surface area for biomarker immobilization. The prepared paper-based biosensor was so small and cheap and also has high stability and sensitivity. For the first time, biotinylated antibody of biomarker (LYVE-1) was immobilized on the surface of working electrode and utilized for the monitoring of specific antigen by simple immune-assay strategy. The designed biosensor showed two separated linear ranges in the range of 20-320 pg ml-1 and 0.625-10 pg ml-1, with the acceptable limit of detection (LOD) of 0.312 pg ml-1. Additionally, engineered immunosensor revealed excellent selectivity that promises its use in complex biological samples and assistance for biomarker-related disease screening in clinical studies.

T Cell Receptor Chain Centricity: The Phenomenon and Potential Applications in Cancer Immunotherapy

T cells are crucial players in adaptive anti-cancer immunity. The gene modification of T cells with tumor antigen-specific T cell receptors (TCRs) was a milestone in personalized cancer immunotherapy. TCR is a heterodimer (either α/β or γ/δ) able to recognize a peptide antigen in a complex with self-MHC molecules. Although traditional concepts assume that an α- and β-chain contribute equally to antigen recognition, mounting data reveal that certain receptors possess chain centricity, i.e., one hemi-chain TCR dominates antigen recognition and dictates its specificity. Chain-centric TCRs are currently poorly understood in terms of their origin and the functional T cell subsets that express them. In addition, the ratio of α- and β-chain-centric TCRs, as well as the exact proportion of chain-centric TCRs in the native repertoire, is generally still unknown today. In this review, we provide a retrospective analysis of studies that evidence chain-centric TCRs, propose patterns of their generation, and discuss the potential applications of such receptors in T cell gene modification for adoptive cancer immunotherapy.

Exploring TCR-like CAR-Engineered Lymphocyte Cytotoxicity against MAGE-A4

TCR-like chimeric antigen receptor (CAR-T) cell therapy has emerged as a game-changing strategy in cancer immunotherapy, offering a broad spectrum of potential antigen targets, particularly in solid tumors containing intracellular antigens. In this study, we investigated the cytotoxicity and functional attributes of in vitro-generated T-lymphocytes, engineered with a TCR-like CAR receptor precisely targeting the cancer testis antigen MAGE-A4. Through viral transduction, T-cells were genetically modified to express the TCR-like CAR receptor and co-cultured with MAGE-A4-expressing tumor cells. Flow cytometry analysis revealed a significant surge in cells expressing activation markers CD69, CD107a, and FasL upon encountering tumor cells, indicating robust T-cell activation and cytotoxicity. Moreover, immune transcriptome profiling unveiled heightened expression of pivotal T-effector genes involved in immune response and cell proliferation regulation. Additionally, multiplex assays also revealed increased cytokine production and cytotoxicity driven by granzymes and soluble Fas ligand (sFasL), suggesting enhanced anti-tumor immune responses. Preliminary in vivo investigations revealed a significant deceleration in tumor growth, highlighting the therapeutic potential of these TCR-like CAR-T cells. Further investigations are warranted to validate these revelations fully and harness the complete potential of TCR-like CAR-T cells in overcoming cancer's resilient defenses.

Adoptive cell therapy for cancer treatment

Adoptive cell therapy (ACT) is a rapidly growing anti-cancer strategy that has shown promise in treating various cancer types. The concept of ACT involves activating patients' own immune cells ex vivo and then transferring them back to the patients to recognize and eliminate cancer cells. Currently, the commonly used ACT includes tumor-infiltrating lymphocytes (TILs), genetically engineered immune cells, and dendritic cells (DCs) vaccines. With the advancement of cell culture and genetic engineering techniques, ACT has been used in clinics to treat malignant hematological diseases and many new ACT-based regimens are in different stages of clinical trials. Here, representative ACT approaches are introduced and the opportunities and challenges for clinical translation of ACT are discussed.

Durable control of metastases in an HLA-A2+ patient with refractory melanoma after low-dose radiotherapy in combination with MAGE-A4 T cell therapy: a case report

There is no currently approved adoptive cellular therapy for solid tumors. Pre-clinical and clinical studies have demonstrated that low-dose radiotherapy (LDRT) can enhance intratumoral T cell infiltration and efficacy. This case report describes a 71-year-old female patient with rectal mucosal melanoma that had developed metastases to liver, lung, mediastinum, axillary nodes, and brain. After systemic therapies had failed, she enrolled in the radiation sub-study of our phase-I clinical trial exploring the safety and efficacy of afamitresgene autoleucel (afami-cel), genetically engineered T cells with a T cell receptor (TCR) targeting the MAGE-A4 tumor antigen in patients with advanced malignancies (NCT03132922). Prior to the infusion of afami-cel, she received concurrent lymphodepleting chemotherapy and LDRT at 5.6 Gy/4 fractions to the liver. Time to partial response was 10 weeks, and duration of overall response was 18.4 weeks. Although the patient progressed at 28 weeks, the disease was well controlled after high-dose radiotherapy to liver metastases and checkpoint inhibitors. As of the last follow-up, she remains alive over two years after LDRT and afami-cel therapy. This report suggests that afami-cel in combination with LDRT safely enhanced clinical benefit. This provides evidence for further exploring the benefit of LDRT in TCR-T cell therapy.

CrossDome: an interactive R package to predict cross-reactivity risk using immunopeptidomics databases

T-cell-based immunotherapies hold tremendous potential in the fight against cancer, thanks to their capacity to specifically targeting diseased cells. Nevertheless, this potential has been tempered with safety concerns regarding the possible recognition of unknown off-targets displayed by healthy cells. In a notorious example, engineered T-cells specific to MAGEA3 (EVDPIGHLY) also recognized a TITIN-derived peptide (ESDPIVAQY) expressed by cardiac cells, inducing lethal damage in melanoma patients. Such off-target toxicity has been related to T-cell cross-reactivity induced by molecular mimicry. In this context, there is growing interest in developing the means to avoid off-target toxicity, and to provide safer immunotherapy products. To this end, we present CrossDome, a multi-omics suite to predict the off-target toxicity risk of T-cell-based immunotherapies. Our suite provides two alternative protocols, i) a peptide-centered prediction, or ii) a TCR-centered prediction. As proof-of-principle, we evaluate our approach using 16 well-known cross-reactivity cases involving cancer-associated antigens. With CrossDome, the TITIN-derived peptide was predicted at the 99+ percentile rank among 36,000 scored candidates (p-value < 0.001). In addition, off-targets for all the 16 known cases were predicted within the top ranges of relatedness score on a Monte Carlo simulation with over 5 million putative peptide pairs, allowing us to determine a cut-off p-value for off-target toxicity risk. We also implemented a penalty system based on TCR hotspots, named contact map (CM). This TCR-centered approach improved upon the peptide-centered prediction on the MAGEA3-TITIN screening (e.g., from 27th to 6th, out of 36,000 ranked peptides). Next, we used an extended dataset of experimentally-determined cross-reactive peptides to evaluate alternative CrossDome protocols. The level of enrichment of validated cases among top 50 best-scored peptides was 63% for the peptide-centered protocol, and up to 82% for the TCR-centered protocol. Finally, we performed functional characterization of top ranking candidates, by integrating expression data, HLA binding, and immunogenicity predictions. CrossDome was designed as an R package for easy integration with antigen discovery pipelines, and an interactive web interface for users without coding experience. CrossDome is under active development, and it is available at https://github.com/AntunesLab/crossdome.

Prospects of Cytomegalovirus-Specific T-Cell Receptors in Clinical Diagnosis and Therapy

Human cytomegalovirus (HCMV) is responsible for widespread infections worldwide. In immunocompetent individuals it is typically latent, while infection or reactivation in immunocompromised individuals can result in severe clinical symptoms or even death. Although there has been significant progress in the treatment and diagnosis of HCMV infection in recent years, numerous shortcomings and developmental limitations persist. There is an urgent need to develop innovative, safe, and effective treatments, as well as to explore early and timely diagnostic strategies for HCMV infection. Cell-mediated immune responses are the primary factor controlling HCMV infection and replication, but the protective role of humoral immune responses remains controversial. T-cells, key effector cells of the cellular immune system, are critical for clearing and preventing HCMV infection. The T-cell receptor (TCR) lies at the heart of T-cell immune responses, and its diversity enables the immune system to differentiate between self and non-self. Given the significant influence of cellular immunity on human health and the indispensable role of the TCR in T-cell immune responses, we posit that the impact of TCR on the development of novel diagnostic and prognostic methods, as well as on patient monitoring and management of clinical HCMV infection, will be far-reaching and profound. High-throughput and single-cell sequencing technologies have facilitated unprecedented quantitative detection of TCR diversity. With these current sequencing technologies, researchers have already obtained a vast number of TCR sequences. It is plausible that in the near future studies on TCR repertoires will be instrumental in assessing vaccine efficacy, immunotherapeutic strategies, and the early diagnosis of HCMV infection.

The Role of Immunotherapy in the Treatment of Rare Central Nervous System Tumors

Establishing novel therapies for rare central nervous system (CNS) tumors is arduous due to challenges in conducting clinical trials in rare tumors. Immunotherapy treatment has been a rapidly developing field and has demonstrated improvements in outcomes for multiple types of solid malignancies. In rare CNS tumors, the role of immunotherapy is being explored. In this article, we review the preclinical and clinical data of various immunotherapy modalities in select rare CNS tumors, including atypical meningioma, aggressive pituitary adenoma, pituitary carcinoma, ependymoma, embryonal tumor, atypical teratoid/rhabdoid tumor, and meningeal solitary fibrous tumor. Among these tumor types, some studies have shown promise; however, ongoing clinical trials will be critical for defining and optimizing the role of immunotherapy for these patients.

Adoptive neoantigen-reactive T cell therapy: improvement strategies and current clinical researches

Neoantigens generated by non-synonymous mutations of tumor genes can induce activation of neoantigen-reactive T (NRT) cells which have the ability to resist the growth of tumors expressing specific neoantigens. Immunotherapy based on NRT cells has made preeminent achievements in melanoma and other solid tumors. The process of manufacturing NRT cells includes identification of neoantigens, preparation of neoantigen expression vectors or peptides, induction and activation of NRT cells, and analysis of functions and phenotypes. Numerous improvement strategies have been proposed to enhance the potency of NRT cells by engineering TCR, promoting infiltration of T cells and overcoming immunosuppressive factors in the tumor microenvironment. In this review, we outline the improvement of the preparation and the function assessment of NRT cells, and discuss the current status of clinical trials related to NRT cell immunotherapy.

Immunotherapeutic approaches in Hepatocellular carcinoma: Building blocks of hope in near future

Hepatocellular carcinoma (HCC) is the most common type of primary hepatic cancer and is among the major causes of mortality due to cancer. Due to the lack of efficient conventional therapeutic options for this cancer, particularly in advanced cases, novel treatments including immunotherapy have been considered. However, despite the encouraging clinical outcomes after implementing these innovative approaches, such as oncolytic viruses (OVs), adoptive cell therapies (ACT), immune checkpoint blockades (ICBs), and cancer vaccines, several factors have restricted their therapeutic effect. The main concern is the existence of an immunosuppressive tumor microenvironment (TME). Combination of different ICBs or ICBs plus tyrosine kinase inhibitors have shown promising results in overcoming these limiting factors to some extent. Combination of programmed cell death ligand-1 (PD-L1) antibody Atezolizumab and vascular endothelial growth factor (VEGF) antibody Bevacizumab has become the standard of care in the first-line therapy for untestable HCC, approved by regulatory agencies. This paper highlighted a wide overview of the direct and indirect immunotherapeutic strategies proposed for the treatment of HCC patients and the common challenges that have hindered their further clinical applications.

Lung cancer immunotherapy: progress, pitfalls, and promises

Lung cancer is the primary cause of mortality in the United States and around the globe. Therapeutic options for lung cancer treatment include surgery, radiation therapy, chemotherapy, and targeted drug therapy. Medical management is often associated with the development of treatment resistance leading to relapse. Immunotherapy is profoundly altering the approach to cancer treatment owing to its tolerable safety profile, sustained therapeutic response due to immunological memory generation, and effectiveness across a broad patient population. Different tumor-specific vaccination strategies are gaining ground in the treatment of lung cancer. Recent advances in adoptive cell therapy (CAR T, TCR, TIL), the associated clinical trials on lung cancer, and associated hurdles are discussed in this review. Recent trials on lung cancer patients (without a targetable oncogenic driver alteration) reveal significant and sustained responses when treated with programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) checkpoint blockade immunotherapies. Accumulating evidence indicates that a loss of effective anti-tumor immunity is associated with lung tumor evolution. Therapeutic cancer vaccines combined with immune checkpoint inhibitors (ICI) can achieve better therapeutic effects. To this end, the present article encompasses a detailed overview of the recent developments in the immunotherapeutic landscape in targeting small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). Additionally, the review also explores the implication of nanomedicine in lung cancer immunotherapy as well as the combinatorial application of traditional therapy along with immunotherapy regimens. Finally, ongoing clinical trials, significant obstacles, and the future outlook of this treatment strategy are also highlighted to boost further research in the field.

Cell Immunotherapy against Melanoma: Clinical Trials Review

Melanoma is one of the most aggressive and therapy-resistant types of cancer, the incidence rate of which grows every year. However, conventional methods of chemo- and radiotherapy do not allow for completely removing neoplasm, resulting in local, regional, and distant relapses. In this case, adjuvant therapy can be used to reduce the risk of recurrence. One of the types of maintenance cancer therapy is cell-based immunotherapy, in which immune cells, such as T-cells, NKT-cells, B cells, NK cells, macrophages, and dendritic cells are used to recognize and mobilize the immune system to kill cancer cells. These cells can be isolated from the patient's peripheral blood or biopsy material and genetically modified, cultured ex vivo, following infusion back into the patient for powerful induction of an anti-tumor immune response. In this review, the advantages and problems of the most relevant methods of cell-based therapy and ongoing clinical trials of adjuvant therapy of melanoma are discussed.

Human iPSC-derived preclinical models to identify toxicity of tumor-specific T cells with clinical potential

The balance between safety and efficacy of T cell therapies remains challenging and T cell mediated toxicities have occurred. The stringent selection of tumor-specific targets and careful selection of tumor-specific T cells using T cell toxicity screenings are essential. In vitro screening options against vital organs or specialized cell subsets would be preferably included in preclinical pipelines, but options remain limited. Here, we set up preclinical models with human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes, epicardial cells, and kidney organoids to investigate toxicity risks of tumor-specific T cells more thoroughly. CD8+T cells reactive against PRAME, HA-1H, CD20, or WT1, currently used or planned to be used in phase I/II clinical studies, were included. Using these hiPSC-derived preclinical models, we demonstrated that WT1-specific T cells caused on-target toxicity that correlated with target gene expression. Multiple measures of T cell reactivity demonstrated this toxicity on the level of T cells and hiPSC-derived target cells. In addition, phenotypic analysis illustrated interaction and crosstalk between infiltrated T cells and kidney organoids. In summary, we demonstrated the benefit of hiPSC-derived models in determining toxicity risks of tumor-specific T cells. Furthermore, our data emphasizes the additional value of other measures of T cell reactivity on top of the commonly used cytokine levels.

Emerging frontiers in immuno- and gene therapy for cancer

BACKGROUND AIMS

The field of cell and gene therapy in oncology has moved rapidly since 2017 when the first cell and gene therapies, Kymriah followed by Yescarta, were approved by the Food and Drug Administration in the United States, followed by multiple other countries. Since those approvals, several new products have gone on to receive approval for additional indications. Meanwhile, efforts have been made to target different cancers, improve the logistics of delivery and reduce the cost associated with novel cell and gene therapies. Here, we highlight various cell and gene therapy-related technologies and advances that provide insight into how these new technologies will speed the translation of these therapies into the clinic.

CONCLUSIONS

In this review, we provide a broad overview of the current state of cell and gene therapy-based approaches for cancer treatment - discussing various effector cell types and their sources, recent advances in both CAR and non-CAR genetic modifications, and highlighting a few promising approaches for increasing in vivo efficacy and persistence of therapeutic drug products.

The Intracellular Proteome as a Source for Novel Targets in CAR-T and T-Cell Engagers-Based Immunotherapy

The impressive clinical success of cancer immunotherapy has motivated the continued search for new targets that may serve to guide potent effector functions in an attempt to efficiently kill malignant cells. The intracellular proteome is an interesting source for such new targets, such as neo-antigens and others, with growing interest in their application for cell-based immunotherapies. These intracellular-derived targets are peptides presented by MHC class I molecules on the cell surface of malignant cells. These disease-specific class I HLA-peptide complexes can be targeted by specific TCRs or by antibodies that mimic TCR-specificity, termed TCR-like (TCRL) antibodies. Adoptive cell transfer of TCR engineered T cells and T-cell-receptor-like based CAR-T cells, targeted against a peptide-MHC of interest, are currently tested as cancer therapeutic agents in pre-clinical and clinical trials, along with soluble TCR- and TCRL-based agents, such as immunotoxins and bi-specific T cell engagers. Targeting the intracellular proteome using TCRL- and TCR-based molecules shows promising results in cancer immunotherapy, as exemplified by the success of the anti-gp100/HLA-A2 TCR-based T cell engager, recently approved by the FDA for the treatment of unresectable or metastatic uveal melanoma. This review is focused on the selection and isolation processes of TCR- and TCRL-based targeting moieties, with a spotlight on pre-clinical and clinical studies, examining peptide-MHC targeting agents in cancer immunotherapy.

Efficacy, Safety, and Challenges of CAR T-Cells in the Treatment of Solid Tumors

Immunotherapy has been the fifth pillar of cancer treatment in the past decade. Chimeric antigen receptor (CAR) T-cell therapy is a newly designed adoptive immunotherapy that is able to target and further eliminate cancer cells by engaging with MHC-independent tumor-antigens. CAR T-cell therapy has exhibited conspicuous clinical efficacy in hematological malignancies, but more than half of patients will relapse. Of note, the efficacy of CAR T-cell therapy has been even more disappointing in solid tumors. These challenges mainly include (1) the failures of CAR T-cells to treat highly heterogeneous solid tumors due to the difficulty in identifying unique tumor antigen targets, (2) the expression of target antigens in non-cancer cells, (3) the inability of CAR T-cells to effectively infiltrate solid tumors, (4) the short lifespan and lack of persistence of CAR T-cells, and (5) cytokine release syndrome and neurotoxicity. In combination with these characteristics, the ideal CAR T-cell therapy for solid tumors should maintain adequate T-cell response over a long term while sparing healthy tissues. This article reviewed the status, clinical application, efficacy, safety, and challenges of CAR T-cell therapies, as well as the latest progress of CAR T-cell therapies for solid tumors. In addition, the potential strategies to improve the efficacy of CAR T-cells and prevent side effects in solid tumors were also explored.

Adoptive cell therapies in thoracic malignancies

Immunotherapy has gained great interest in thoracic malignancies in the last decade, first in non-small cell lung cancer (NSCLC), but also more recently in small-cell lung cancer (SCLC) and malignant pleural mesothelioma (MPM). However, while 15-20% of patients will greatly benefit from immune checkpoint blockers (ICBs), a vast majority will rapidly exhibit resistance. Reasons for this are multiple: non-immunogenic tumors, immunosuppressive tumor microenvironment or defects in immune cells trafficking to the tumor sites being some of the most frequent. Current progress in adoptive cell therapies could offer a way to overcome these hurdles and bring effective immune cells to the tumor site. In this review, we discuss advantages, limits and future perspectives of adoptive cell therapy (ACT) in thoracic malignancies from lymphokine-activated killer cells (LAK), cytokine-induced killer cells (CIK), natural killer cells (NK), dendritic cells (DC) vaccines and tumor-infiltrating lymphocytes (TILs) to TCR engineering and CARs. Trials are still in their early phases, and while there may still be many limitations to overcome, a combination of these different approaches with ICBs, chemotherapy and/or radiotherapy could vastly improve the way we treat thoracic cancers.

Influence of Culture Conditions on Ex Vivo Expansion of T Lymphocytes and Their Function for Therapy: Current Insights and Open Questions

Ex vivo expansion of T lymphocytes is a central process in the generation of cellular therapies targeted at tumors and other disease-relevant structures, which currently cannot be reached by established pharmaceuticals. The influence of culture conditions on T cell functions is, however, incompletely understood. In clinical applications of ex vivo expanded T cells, so far, a relatively classical standard cell culture methodology has been established. The expanded cells have been characterized in both preclinical models and clinical studies mainly using a therapeutic endpoint, for example antitumor response and cytotoxic function against cellular targets, whereas the influence of manipulations of T cells ex vivo including transduction and culture expansion has been studied to a much lesser detail, or in many contexts remains unknown. This includes the circulation behavior of expanded T cells after intravenous application, their intracellular metabolism and signal transduction, and their cytoskeletal (re)organization or their adhesion, migration, and subsequent intra-tissue differentiation. This review aims to provide an overview of established T cell expansion methodologies and address unanswered questions relating in vivo interaction of ex vivo expanded T cells for cellular therapy.

Development of Cancer Immunotherapies

Cancer immunotherapy, or the utilization of components of the immune system to target and eliminate cancer, has become a highly active area of research in the past several decades and a common treatment strategy for several cancer types. The concept of harnessing the immune system for this purpose originated over 100 years ago when a physician by the name of William Coley successfully treated several of his cancer patients with a combination of live and attenuated bacteria, later known as "Coley's Toxins", after observing a subset of prior patients enter remission following their diagnosis with the common bacterial infection, erysipelas. However, it was not until late in the twentieth century that cancer immunotherapies were developed for widespread use, thereby transforming the treatment landscape of numerous cancer types. Pivotal studies elucidating molecular and cellular functions of immune cells, such as the discovery of IL-2 and production of monoclonal antibodies, fostered the development of novel techniques for studying the immune system and ultimately the development and approval of several cancer immunotherapies by the United States Food and Drug Association in the 1980s and 1990s, including the tuberculosis vaccine-Bacillus Calmette-Guérin, IL-2, and the CD20-targeting monoclonal antibody. Approval of the first therapeutic cancer vaccine, Sipuleucel-T, for the treatment of metastatic castration-resistant prostate cancer and the groundbreaking success and approval of immune checkpoint inhibitors and chimeric antigen receptor T cell therapy in the last decade, have driven an explosion of interest in and pursuit of novel cancer immunotherapy strategies. A broad range of modalities ranging from antibodies to adoptive T cell therapies is under investigation for the generalized treatment of a broad spectrum of cancers as well as personalized medicine. This chapter will focus on the recent advances, current strategies, and future outlook of immunotherapy development for the treatment of cancer.

Immune escape mechanisms and therapeutic approaches in cancer: the cancer-immunity cycle

The introduction of immune checkpoint inhibitors has changed the therapeutic possibilities for various cancer types. However, despite the success in some entities, a significant fraction of patients does not respond to immune checkpoint inhibitors. A functioning cancer-immunity cycle is needed as the precondition for a clinically meaningful response to immune checkpoint inhibitors. It is assumed that only if each step of the cycle is activated and functioning properly, immune checkpoint inhibitors induce a meaningful immune response. However, an activated cancer-immunity cycle might not be present equally in each patient and cancer type. Ideally, treatment concepts should consider each single step of the cancer-immunity cycle and provide personalized treatment approaches, allowing the adaption to functioning and malfunctioning steps of the individual patient’s specific cancer-immunity cycle. In the following review, we provide an overview of the single steps of the cancer-immunity cycle as well as the impact of malfunctioning steps on the generation of an effective tumor-specific immune response.

Review article: hepatitis B-current and emerging therapies

BACKGROUND

The hepatitis B virus (HBV) affects an estimated 290 million individuals worldwide and is responsible for approximately 900 000 deaths annually, mostly from complications of cirrhosis and hepatocellular carcinoma. Although current treatment is effective at preventing complications of chronic hepatitis B, it is not curative, and often must be administered long term. There is a need for safe, effective, finite duration curative therapy.

AIM

Our aim was to provide a concise, up to date review of all currently available and emerging treatment options for chronic hepatitis B.

METHODS

We conducted a search of PubMed, clinicaltrials.gov, major meeting abstracts and pharmaceutical websites for publications and communications on current and emerging therapies for HBV.

RESULTS

Currently approved treatment options for chronic hepatitis B include peginterferon alpha-2a and nucleos(t)ide analogues. Both options do not offer a 'complete cure' (clearance of covalently closed circular DNA (cccDNA) and integrated HBV DNA) and rarely achieve a 'functional cure' (hepatitis B surface antigen (HBsAg) loss). An improved understanding of the viral lifecycle, immunopathogenesis and recent advances in drug delivery technologies have led to many novel therapeutic approaches that are currently being evaluated in clinical trials including targeting of viral entry, cccDNA, viral transcription, core protein, and release of HBsAg and HBV polymerase. Additionally, novel immunological approaches that include targeting the innate and adaptive immune system and therapeutic vaccination are being pursued.

CONCLUSION

The breadth and scope of novel therapies in development hold promise for regimen/s that will achieve functional cure.

A Costimulatory CAR Improves TCR-based Cancer Immunotherapy

T-cell receptors (TCR) recognize intracellular and extracellular cancer antigens, allowing T cells to target many tumor antigens. To sustain proliferation and persistence, T cells require not only signaling through the TCR (signal 1), but also costimulatory (signal 2) and cytokine (signal 3) signaling. Because most cancer cells lack costimulatory molecules, TCR engagement at the tumor site results in incomplete T-cell activation and transient antitumor effects. To overcome this lack of signal 2, we genetically modified tumor-specific T cells with a costimulatory chimeric antigen receptor (CoCAR). Like classical CARs, CoCARs combine the antigen-binding domain of an antibody with costimulatory endodomains to trigger T-cell proliferation, but CoCARs lack the cytotoxic CD3ζ chain to avoid toxicity to normal tissues. We first tested a CD19-targeting CoCAR in combination with an HLA-A*02:01-restricted, survivin-specific transgenic TCR (sTCR) in serial cocultures with leukemia cells coexpressing the cognate peptide-HLA complex (signal 1) and CD19 (signal 2). The CoCAR enabled sTCR+ T cells to kill tumors over a median of four additional tumor challenges. CoCAR activity depended on CD19 but was maintained in tumors with heterogeneous CD19 expression. In a murine tumor model, sTCR+CoCAR+ T cells improved tumor control and prolonged survival compared with sTCR+ T cells. We further evaluated the CoCAR in Epstein-Barr virus-specific T cells (EBVST). CoCAR-expressing EBVSTs expanded more rapidly than nontransduced EBVSTs and delayed tumor progression in an EBV+ murine lymphoma model. Overall, we demonstrated that the CoCAR can increase the activity of T cells expressing both native and transgenic TCRs and enhance antitumor responses.

Cancer Immunotherapies: What the Perioperative Physician Needs to Know

Purpose of Review

For patients with cancer, treatment may include combination therapy, including surgery and immunotherapy. Here, we review perioperative considerations for the patient prescribed immunotherapeutic agents.

Recent Findings

The perioperative period is a poignant moment in the journey of a patient with cancer, potentially deemed most influential compared to other moments in the care continuum. Several immunotherapeutic medications have been employed near the time of surgery to potentially increase effectiveness. Of the various drug classes, including immune checkpoint inhibitors, cytokines, toll-like receptor agonists, and oncolytic viruses, among others, several notable immune-related adverse effects were noted. They range from minor effects to more serious ones, such as renal failure, myocarditis, and tumor growth.

Summary

Surgery and immunotherapy are often employed in combination for primary treatment and prevention of cancer recurrence. Careful review and consideration of the pharmacokinetics, pharmacodynamics, and toxicities of immunotherapy benefit the perioperative physician and their patients.

Neoantigens and their potential applications in tumor immunotherapy

The incidence of malignant tumors is increasing, the majority of which are associated with high morbidity and mortality rates worldwide. The traditional treatment method for malignant tumors is surgery, coupled with radiotherapy or chemotherapy. However, these therapeutic strategies are frequently accompanied with adverse side effects. Over recent decades, tumor immunotherapy shown promise in demonstrating notable efficacy for the treatment of cancer. With the development of sequencing technology and bioinformatics algorithms, neoantigens have become compelling targets for cancer immunotherapy due to high levels of immunogenicity. In addition, neoantigen-based vaccines have demonstrated potential for cancer therapy, primarily by augmenting T-cell responses. Neoantigens have also been shown to be effective in immune checkpoint blockade therapy. Therefore, neoantigens may serve to be predictive biomarkers and synergistic treatment targets in cancer immunotherapy. The aim of the present review was to provide an overview of the recent progress in the classification, screening and clinical application of neoantigens for cancer therapy.

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.

Double Strike Approach for Tumor Attack: Engineering T Cells Using a CD40L:CD28 Chimeric Co-Stimulatory Switch Protein for Enhanced Tumor Targeting in Adoptive Cell Therapy

Activation of co-stimulatory pathways in cytotoxic T lymphocytes expressing chimeric antigen receptors (CARs) have proven to boost effector activity, tumor rejection and long-term T cell persistence. When using antigen-specific T cell receptors (TCR) instead of CARs, the lack of co-stimulatory signals hampers robust antitumoral response, hence limiting clinical efficacy. In solid tumors, tumor stroma poses an additional hurdle through hindrance of infiltration and active inhibition. Our project aimed at generating chimeric co-stimulatory switch proteins (CSP) consisting of intracellular co-stimulatory domains (ICD) fused to extracellular protein domains (ECD) for which ligands are expressed in solid tumors. The ECD of CD40L was selected for combination with the ICD from the CD28 protein. With this approach, it was expected to not only provide co-stimulation and strengthen the TCR signaling, but also, through the CD40L ECD, facilitate the activation of tumor-resident antigen-presenting cells (APCs), modulate activation of tumor endothelium and induce TCR-MHC independent apoptotic effect on tumor cells. Since CD28 and CD40L belong to different classes of transmembrane proteins (type I and type II, respectively), creating a chimeric protein presented a structural and functional challenge. We present solutions to this challenge describing different CSP formats that were successfully expressed in human T cells along with an antigen-specific TCR. The level of surface expression of the CSPs depended on their distinct design and the state of T cell activation. In particular, CSPs were upregulated by TCR stimulation and downregulated following interaction with CD40 on target cells. Ligation of the CSP in the context of TCR-stimulation modulated intracellular signaling cascades and led to improved TCR-induced cytokine secretion and cytotoxicity. Moreover, the CD40L ECD exhibited activity as evidenced by effective maturation and activation of B cells and DCs. CD40L:CD28 CSPs are a new type of switch proteins designed to exert dual beneficial antitumor effect by acting directly on the gene-modified T cells and simultaneously on tumor cells and tumor-supporting cells of the TME. The observed effects suggest that they constitute a promising tool to be included in the engineering process of T cells to endow them with complementary features for improved performance in the tumor milieu.

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.

Lentiviral Vectors for T Cell Engineering: Clinical Applications, Bioprocessing and Future Perspectives

Lentiviral vectors have played a critical role in the emergence of gene-modified cell therapies, specifically T cell therapies. Tisagenlecleucel (Kymriah), axicabtagene ciloleucel (Yescarta) and most recently brexucabtagene autoleucel (Tecartus) are examples of T cell therapies which are now commercially available for distribution after successfully obtaining EMA and FDA approval for the treatment of blood cancers. All three therapies rely on retroviral vectors to transduce the therapeutic chimeric antigen receptor (CAR) into T lymphocytes. Although these innovations represent promising new therapeutic avenues, major obstacles remain in making them readily available tools for medical care. This article reviews the biological principles as well as the bioprocessing of lentiviral (LV) vectors and adoptive T cell therapy. Clinical and engineering successes, shortcomings and future opportunities are also discussed. The development of Good Manufacturing Practice (GMP)-compliant instruments, technologies and protocols will play an essential role in the development of LV-engineered T cell therapies.

Profiling T cell receptor β-chain in responders after immunization with recombinant hepatitis B vaccine

BACKGROUND

T cells with edited T cell receptor β-chain variable (TRBV) are involved in the immune response to recombinant hepatitis B surface antigen (rHBsAg) vaccine and the production of hepatitis B surface antibody (HBsAb). The immune repertoire (IR) profile and mechanism of vaccination positive responders (VPR) with rHBsAg are not fully understood.

METHODS

The IR of six VPRs (HBsAb+, HbsAg-) with rHBsAg vaccination was established by the high throughput sequencing technique and bioinformatics analysis and compared with those in five vaccination negative responders (VNRs) (HbsAb-, HbsAg-) who were also inoculated with rHBsAg. The repertoire features of the BV, BJ and V (CDR3) J genes and immune diversity in peripheral blood mononuclear cells, respectively, were analyzed for each subject.

RESULTS

There was no significant difference in sequencing amplification indices of each sample. However, TRBV15/BJ2-3 demonstrated significantly high expression levels in VPR compared to those in the VNR group (both p < 0.05). Further results showed that the BV15/BJ2-5 level was significantly increased for VPR compared to that of VNR group. Interestingly, the motif of CDR3 in TRBV15/BJ2-5 was mostly expressed as "GGETQ" or "GETQ". Additionally, there was no remarkable difference between the two groups of distribution with respect to the different clone expression levels of V (CDR3) J.

CONCLUSIONS

The features of IR in the VPR and VNR will contribute to the exploration of the mechanism of the positive response to rHBsAg, and also contribute to development of optimized hepatitis B vaccine, in addition to providing a partial interpretation of the VNR who has a relatively low infection with HBV.

Innovative and Promising Strategies to Enhance Effectiveness of Immunotherapy for CNS Tumors: Where Are We?

Although there are several immunotherapy approaches for the treatment of Central Nervous System (CNS) tumors under evaluation, currently none of these approaches have received approval from the regulatory agencies. CNS tumors, especially glioblastomas, are tumors characterized by highly immunosuppressive tumor microenvironment, limiting the possibility of effectively eliciting an immune response. Moreover, the peculiar anatomic location of these tumors poses relevant challenges in terms of safety, since uncontrolled hyper inflammation could lead to cerebral edema and cranial hypertension. The most promising strategies of immunotherapy in neuro-oncology consist of the use of autologous T cells redirected against tumor cells through chimeric antigen receptor (CAR) constructs or genetically modified T-cell receptors. Trials based on native or genetically engineered oncolytic viruses and on vaccination with tumor-associated antigen peptides are also under evaluation. Despite some sporadic complete remissions achieved in clinical trials, the outcome of patients with CNS tumors treated with different immunotherapeutic approaches remains poor. Based on the lessons learned from these unsatisfactory experiences, novel immune-therapy approaches aimed at overcoming the profound immunosuppressive microenvironment of these diseases are bringing new hope to reach the cure for CNS tumors.

Cell Therapy With TILs: Training and Taming T Cells to Fight Cancer

The rationale behind cancer immunotherapy is based on the unequivocal demonstration that the immune system plays an important role in limiting cancer initiation and progression. Adoptive cell therapy (ACT) is a form of cancer immunotherapy that utilizes a patient’s own immune cells to find and eliminate tumor cells, however, donor immune cells can also be employed in some cases. Here, we focus on T lymphocyte (T cell)-based cancer immunotherapies that have gained significant attention after initial discoveries that graft-versus-tumor responses were mediated by T cells. Accumulating knowledge of T cell development and function coupled with advancements in genetics and data science has enabled the use of a patient’s own (autologous) T cells for ACT (TIL ACTs). In TIL ACT, tumor-infiltrating lymphocytes (TILs) are collected from resected tumor material, enhanced and expanded ex-vivo, and delivered back to the patient as therapeutic agents. ACT with TILs has been shown to cause objective tumor regression in several types of cancers including melanoma, cervical squamous cell carcinoma, and cholangiocarcinoma. In this review, we provide a brief history of TIL ACT and discuss the current state of TIL ACT clinical development in solid tumors. We also discuss the niche of TIL ACT in the current cancer therapy landscape and potential strategies for patient selection.

CAR-T cells and BiTEs in solid tumors: challenges and perspectives

Chimeric antigen receptor (CAR)-modified T cells and BiTEs are both immunotherapies which redirect T cell specificity against a tumor-specific antigen through the use of antibody fragments. They demonstrated remarkable efficacy in B cell hematologic malignancies, thus paving the way for their development in solid tumors. Nonetheless, the use of such new drugs to treat solid tumors is not straightforward. So far, the results from early phase clinical trials are not as impressive as expected but many improvements are under way. In this review we present an overview of the clinical development of CAR-T cells and BiTEs targeting the main antigens expressed by solid tumors. We emphasize the most frequent hurdles encountered by either CAR-T cells or BiTEs, or both, and summarize the strategies that have been proposed to overcome these obstacles.

CRISPRing future medicines

Introduction: The ability to engineer mammalian genomes in a quick and cost-effective way has led to rapid adaptation of CRISPR technology in biomedical research. CRISPR-based engineering has the potential to accelerate drug discovery, to support the reduction of high attrition rate in drug development and to enhance development of cell and gene-based therapies.Areas covered: How CRISPR technology is transforming drug discovery is discussed in this review. From target identification to target validation in both in vitro and in vivo models, CRISPR technology is positively impacting the early stages of drug development by providing a straightforward way to genome engineering. This property also attracted attention for CRISPR application in the cell and gene therapy area.Expert opinion: CRISPR technology is rapidly becoming the preferred tool for genome engineering and nowadays it is hard to imagine the drug discovery pipeline without this technology. With the years to come, CRISPR technology will undoubtedly be further refined and will flourish into a mature technology that will play a key role in supporting genome engineering requirements in the drug discovery pipeline as well as in cell and gene therapy development.

TCR Gene Therapy: Challenges, Opportunities, and Future Directions

Adoptive immunotherapy with gene-engineered T cells has provided new treatment options for cancer patients [...].