CAR T-Cell Therapy: Progress and Prospects

CAR-NK cell therapy in AML: Current treatment, challenges, and advantage

Over the last decade, discovery of novel therapeutic method has been attention by the researchers and has changed the therapeutic perspective of hematological malignancies. Although NK cell play a pivotal role in the elimination of abnormal and cancerous cells, there are evidence that NK cell are disarm in hematological malignancy. Chimeric antigen receptor NK (CAR-NK) cell therapy, which includes the engineering of NK cells to detect tumor-specific antigens and, as a result, clear of cancerous cells, has created various clinical advantage for several human malignancies treatment. In the current review, we summarized NK cell dysfunction and CAR-NK cell based immunotherapy to treat AML patient.

shRNA-mediated gene silencing of HDAC11 empowers CAR-T cells against prostate cancer

Epigenetic mechanisms are involved in several cellular functions, and their role in the immune system is of prime importance. Histone deacetylases (HDACs) are an important set of enzymes that regulate and catalyze the deacetylation process. HDACs have been proven beneficial targets for improving the efficacy of immunotherapies. HDAC11 is an enzyme involved in the negative regulation of T cell functions. Here, we investigated the potential of HDAC11 downregulation using RNA interference in CAR-T cells to improve immunotherapeutic outcomes against prostate cancer. We designed and tested four distinct short hairpin RNA (shRNA) sequences targeting HDAC11 to identify the most effective one for subsequent analyses. HDAC11-deficient CAR-T cells (shD-NKG2D-CAR-T) displayed better cytotoxicity than wild-type CAR-T cells against prostate cancer cell lines. This effect was attributed to enhanced activation, degranulation, and cytokine release ability of shD-NKG2D-CAR-T when co-cultured with prostate cancer cell lines. Our findings reveal that HDAC11 interference significantly enhances CAR-T cell proliferation, diminishes exhaustion markers PD-1 and TIM3, and promotes the formation of T central memory TCM populations. Further exploration into the underlying molecular mechanisms reveals increased expression of transcription factor Eomes, providing insight into the regulation of CAR-T cell differentiation. Finally, the shD-NKG2D-CAR-T cells provided efficient tumor control leading to improved survival of tumor-bearing mice in vivo as compared to their wild-type counterparts. The current study highlights the potential of HDAC11 downregulation in improving CAR-T cell therapy. The study will pave the way for further investigations focused on understanding and exploiting epigenetic mechanisms for immunotherapeutic outcomes.

Palliative Care in Patients with Hematological Malignancies

Palliative care is an attempt to improve the quality of life of patients and their relatives who have lost the chance of a cure. Interventions to improve the quality of life of patients include physical, mental, and psychosocial problems. It is known that symptoms such as pain, fatigue, loss of appetite, and feeling unwell, which often cause deterioration in quality of life, are improved with palliative care support. It is seen that palliative care support, which is mostly recommended in the end-of-life period of patients with solid tumors, is not recommended for patients with hematological malignancies. In fact, patients with hematological malignancies face physical, mental, and economic difficulties due to the intense treatment protocols required for their disease and the side effects of the treatments. Compared to patients with solid tumors, patients with hematological malignancies have a higher frequency of hospitalization and intensive care unit admission. For these reasons, our aim is to define the palliative care needs of patients with hematologic malignancies, understand the barriers to palliative care and end-of-life care, and offer solutions to improve the quality of life and care of patients with hematologic malignancies.

The potential of plant extracts in cell therapy

Cell therapy is the frontier technology of biotechnology innovation and the most promising method for the treatment of refractory diseases such as tumours. However, cell therapy has disadvantages, such as toxicity and poor therapeutic effects. Plant extracts are natural, widely available, and contain active small molecule ingredients that are widely used in the treatment of various diseases. By studying the effect of plant extracts on cell therapy, active plant extracts that have positive significance in cell therapy can be discovered, and certain contributions to solving the current problems of attenuation and adjuvant therapy in cell therapy can be made. Therefore, this article reviews the currently reported effects of plant extracts in stem cell therapy and immune cell therapy, especially the effects of plant extracts on the proliferation and differentiation of mesenchymal stem cells and nerve stem cells and the potential role of plant extracts in chimeric antigen receptor T-cell immunotherapy (CAR-T) and T-cell receptor modified T-cell immunotherapy (TCR-T), in the hope of encouraging further research and clinical application of plant extracts in cell therapy.

c-Met specific CAR-T cells as a targeted therapy for non-small cell lung cancer cell A549

Non-small cell lung cancer (NSCLC) is considered to be one of the most prevalent and fatal malignancies, with a poor survival rate. Chimeric antigen receptor T cell (CAR-T) cell therapy is one of the most exciting directions in the field of Cellular immunotherapy. Therefore, CAR-T cells that target c-Met have been developed for use in NSCLC therapy and might be a potential therapeutic strategy. The anti c-Met ScFv structure was fused with the transmembrane and intracellular domains. Using a lentiviral vector to load the c-Met CAR gene, then transfected the c-Met CAR lentiviral into human T cells to obtain the second generation c-Met CAR-T expressing CARs stably. In vitro co-culture, experiments revealed that CAR-T cells have high proliferative activity and the potential to secrete cytokines (IL-2, TNF-α, and IFN-γ). c-Met CAR-T cells showed special cellular cytotoxicity in LDH release assay. A subcutaneous tumor model in nude mice was used to test the anticancer effectiveness of c-Met CAR-T cells in vivo. For c-Met positive NSCLC tissue, according to tumor volume, weight, fluorescence intensity, and immunohistochemical detection, c-Met CAR-T cells had stronger tumor growth suppression compared to untransduced T cells. HE staining revealed that c-Met CAR-T cells did not produced side effects in nude mice. Taken together, we provided useful method to generate c-Met CAR- T cells, which exhibit enhanced cytotoxicity against NSCLC cells in vitro and in vivo. Thus, providing a new therapeutic avenue for treating NSCLC clinically.

Highlights

(1) c-Met CAR-T capable of stably expressing c-Met CARs were constructed.

(2) c-Met CAR-T have strong anti-tumor ability and proliferation ability in vitro.

(3) c-Met CAR-T can effectively inhibit the growth of A549 cells subcutaneous xenografts.

Barriers to seeking psychosocial support among adult patients with hematologic neoplasms: a qualitative study

PURPOSE

This study aims to explore the barriers that adult patients with hematologic neoplasms experience when seeking psychosocial support.

METHODS

A descriptive qualitative approach was used to investigate the experiences of patients with hematologic neoplasms. Face-to-face, semi-structured, in-depth individual interviews were conducted between June and October 2020 with 17 patients diagnosed with hematologic neoplasms. The interviews were audio-recorded and transcribed verbatim. A thematic analysis was performed to identify the essential themes.

RESULTS

Seventeen patients aged 28-67 years completed the interviews. Two themes and six subthemes were identified that describe barriers to seeking psychosocial support. Internal barriers included limited communication, negative emotions, social avoidance, and focusing on treatment rather than psychosocial needs; external barriers included traditional cultural influences and lack of professional support.

CONCLUSIONS

Significant others were the key source for psychosocial support for patients with hematologic neoplasms. Tackling diverse barriers to accessing psychosocial support remains a challenge for these patients. Healthcare providers should continually assess and provide effective support.

Improved Immunotherapy Efficacy by Vascular Modulation

Several strategies have been developed to modulate the tumour vasculature for cancer therapy including anti-angiogenesis and vascular normalisation. Vasculature modulation results in changes to the tumour microenvironment including oxygenation and immune cell infiltration, therefore lending itself to combination with cancer therapy. The development of immunotherapies has led to significant improvements in cancer treatment. Particularly promising are immune checkpoint blockade and CAR T cell therapies, which use antibodies against negative regulators of T cell activation and T cells reprogrammed to better target tumour antigens, respectively. However, while immunotherapy is successful in some patients, including those with advanced or metastatic cancers, only a subset of patients respond. Therefore, better predictors of patient response and methods to overcome resistance warrant investigation. Poor, or periphery-limited, T cell infiltration in the tumour is associated with poor responses to immunotherapy. Given that (1) lymphocyte recruitment requires leucocyte-endothelial cell adhesion and (2) the vasculature controls tumour oxygenation and plays a pivotal role in T cell infiltration and activation, vessel targeting strategies including anti-angiogenesis and vascular normalisation in combination with immunotherapy are providing possible new strategies to enhance therapy. Here, we review the progress of vessel modulation in enhancing immunotherapy efficacy.

Locoregional infusion of HER2-specific CAR T cells in children and young adults with recurrent or refractory CNS tumors: an interim analysis

Locoregional delivery of chimeric antigen receptor (CAR) T cells has resulted in objective responses in adults with glioblastoma, but the feasibility and tolerability of this approach is yet to be evaluated for pediatric central nervous system (CNS) tumors. Here we show that engineering of a medium-length CAR spacer enhances the therapeutic efficacy of human erb-b2 receptor tyrosine kinase 2 (HER2)-specific CAR T cells in an orthotopic xenograft medulloblastoma model. We translated these findings into BrainChild-01 ( NCT03500991 ), an ongoing phase 1 clinical trial at Seattle Children's evaluating repetitive locoregional dosing of these HER2-specific CAR T cells to children and young adults with recurrent/refractory CNS tumors, including diffuse midline glioma. Primary objectives are assessing feasibility, safety and tolerability; secondary objectives include assessing CAR T cell distribution and disease response. In the outpatient setting, patients receive infusions via CNS catheter into either the tumor cavity or the ventricular system. The initial three patients experienced no dose-limiting toxicity and exhibited clinical, as well as correlative laboratory, evidence of local CNS immune activation, including high concentrations of CXCL10 and CCL2 in the cerebrospinal fluid. This interim report supports the feasibility of generating HER2-specific CAR T cells for repeated dosing regimens and suggests that their repeated intra-CNS delivery might be well tolerated and activate a localized immune response in pediatric and young adult patients.

Evolving AAV-delivered therapeutics towards ultimate cures

Gene therapy has entered a new era after decades-long efforts, where the recombinant adeno-associated virus (AAV) has stood out as the most potent vector for in vivo gene transfer and demonstrated excellent efficacy and safety profiles in numerous preclinical and clinical studies. Since the first AAV-derived therapeutics Glybera was approved by the European Medicines Agency (EMA) in 2012, there is an increasing number of AAV-based gene augmentation therapies that have been developed and tested for treating incurable genetic diseases. In the subsequent years, the United States Food and Drug Administration (FDA) approved two additional AAV gene therapy products, Luxturna and Zolgensma, to be launched into the market. Recent breakthroughs in genome editing tools and the combined use with AAV vectors have introduced new therapeutic modalities using somatic gene editing strategies. The promising outcomes from preclinical studies have prompted the continuous evolution of AAV-delivered therapeutics and broadened the scope of treatment options for untreatable diseases. Here, we describe the clinical updates of AAV gene therapies and the latest development using AAV to deliver the CRISPR components as gene editing therapeutics. We also discuss the major challenges and safety concerns associated with AAV delivery and CRISPR therapeutics, and highlight the recent achievement and toxicity issues reported from clinical applications.

Nanomedicine-Combined Immunotherapy for Cancer

BACKGROUND

Immunotherapy for cancer includes Chimeric Antigen Receptor (CAR)-T cells, CAR-natural Killer (NK) cells, PD1, and the PD-L1 inhibitor. However, the proportion of patients who respond to cancer immunotherapy is not satisfactory. Concurrently, nanotechnology has experienced a revolution in cancer diagnosis and therapy. There are few clinically approved nanoparticles that can selectively bind and target cancer cells and incorporate molecules, although many therapeutic nanocarriers have been approved for clinical use. There are no systematic reviews outlining how nanomedicine and immunotherapy are used in combination to treat cancer.

OBJECTIVE

This review aims to illustrate how nanomedicine and immunotherapy can be used for cancer treatment to overcome the limitations of the low proportion of patients who respond to cancer immunotherapy and the rarity of nanomaterials in clinical use.

METHODS

A literature review of MEDLINE, PubMed / PubMed Central, and Google Scholar was performed. We performed a structured search of literature reviews on nanoparticle drug-delivery systems, which included photodynamic therapy, photothermal therapy, photoacoustic therapy, and immunotherapy for cancer. Moreover, we detailed the advantages and disadvantages of the various nanoparticles incorporated with molecules to discuss the challenges and solutions associated with cancer treatment.

CONCLUSION

This review identified the advantages and disadvantages associated with improving health care and outcomes. The findings of this review confirmed the importance of nanomedicinecombined immunotherapy for improving the efficacy of cancer treatment. It may become a new way to develop novel cancer therapeutics using nanomaterials to achieve synergistic anticancer immunity.

Pseudotyping Lentiviral Vectors: When the Clothes Make the Virus

Delivering transgenes to human cells through transduction with viral vectors constitutes one of the most encouraging approaches in gene therapy. Lentivirus-derived vectors are among the most promising vectors for these approaches. When the genetic modification of the cell must be performed in vivo, efficient specific transduction of the cell targets of the therapy in the absence of off-targeting constitutes the Holy Grail of gene therapy. For viral therapy, this is largely determined by the characteristics of the surface proteins carried by the vector. In this regard, an important property of lentiviral vectors is the possibility of being pseudotyped by envelopes of other viruses, widening the panel of proteins with which they can be armed. Here, we discuss how this is achieved at the molecular level and what the properties and the potentialities of the different envelope proteins that can be used for pseudotyping these vectors are.

T-cell-based immunotherapy in colorectal cancer

Colorectal cancer (CRC) is the leading cause of cancer death worldwide. CRC therapeutic strategies include surgical resection, chemotherapy, radiotherapy, and other approaches. However, patients with metastatic CRC have worse prognoses. In recent years, T-cell-based immunotherapy has elicited promising responses in B-cell malignancies, melanoma, and lung cancer, but most CRC patients are resistant to immunotherapy, chemotherapy, and targeted therapy. Immune checkpoint inhibitors have shown encouraging results in non-small cell lung cancer, melanoma, and other cancers, but immune checkpoint blockade is only effective for CRC subset with microsatellite instability. Other immunotherapies, such as cytokines, cancer vaccines, small molecules, oncolytic viruses, and chimeric antigen-receptor therapy, are currently in use against CRC. This review analyzes recent developments in immunotherapy for CRC treatment as well as the challenges in overcoming resistance.

CD4+ T cells engineered with FVIII-CAR and murine Foxp3 suppress anti-factor VIII immune responses in hemophilia a mice

Although protein replacement therapy provides effective treatment for hemophilia A patients, about a third of severe patients develop neutralizing inhibitor antibodies to factor VIII. Adoptive transfer of regulatory T cells (Tregs) has shown promise in treating unwanted immune responses. In previous studies, transferred polyclonal Tregs ameliorated the anti-factor VIII immune responses in hemophilia A mice. In addition, factor VIII-primed Tregs demonstrated increased suppressive function. However, antigen-specific Tregs are a small fraction of the total lymphocyte population. To generate large numbers of factor VIII-specific Tregs, the more abundant murine primary CD4⁺ T cells were lentivirally transduced ex vivo to express Foxp3 and a chimeric antigen receptor specific to factor VIII (F8CAR). Transduced cells significantly inhibited the proliferation of factor VIII-specific effector T cells in suppression assays. To monitor the suppressive function of the transduced chimeric antigen receptor expressing T cells in vivo, engineered CD4⁺CD25⁺Foxp3⁺F8CAR-Tregs were sorted and adoptively transferred into hemophilia A mice that are treated with hydrodynamically injected factor VIII plasmid. Mice receiving engineered F8CAR-Tregs showed maintenance of factor VIII clotting activity and did not develop anti-factor VIII inhibitors, while control CD4⁺T cell or PBS recipient mice developed inhibitors and had a sharp decrease in factor VIII activity. These results show that CD4⁺ cells lentivirally transduced to express Foxp3 and F8CAR can promote factor VIII tolerance in a murine model. With further development and testing, this approach could potentially be applied to human hemophilia patients.

Antibody-drug conjugates, cancer immunotherapy, and metronomic chemotherapy as novel approaches in cancer management

Treatment of cancer is a major challenge even though the pathophysiology is becoming clearer with time. A number of new chemical entities are developed to target cancer growth inhibition, but the targeted delivery of these products still needs novel research. This is of utmost importance not only for higher efficacy but also for a reduction in systemic toxicity and cost of treatment. Although multiple novel targets and molecules are being researched, most of them could not pass the regulatory approval process, due to low benefit-risk ratio and lack of target specificity. Failure of a majority of these drugs was in part due to their superiority claimed via surrogate markers. Despite these, currently, more than 100 chemotherapeutic agents are in practice. This review paper discusses in detail the molecular basis, drug discovery, and pros and cons over conventional treatment approaches of three novel approaches in cancer therapy, i.e., (i) antibody-drug conjugates, (ii) cancer immunotherapy, and (iii) metronomic chemotherapy. All the drugs developed using these three novel approaches were compared against the established treatment regimens in clinical trials with clinical end points, such as overall survival, progression-free survival, and quality of life.

Fasten the seat belt: Increasing safety of CAR T-cell therapy

After the recent success and approvals of chimeric antigen receptor (CAR) T cells in haematological malignancies, its efficacy is currently evaluated in a broad spectrum of tumor entities including melanoma. However, severe and potentially life-threatening side effects like cytokine release syndrome, neurologic toxicities, and the competing risk of morbidity and mortality from the treatment itself are still a major limiting factor in the current CAR T-cell landscape. In addition, especially in solid tumors, the lack of ideal target antigens to avoid on-target/off-tumor toxicities also restricts its use. While various groups are working on strategies to boost CAR T-cell efficacy, mechanisms to increase engineered T-cell safety should not move out of focus. Thus, the aim of this article is to summarize and to discuss current and potential future strategies and mechanisms to increase CAR T-cell safety in order to enable the wide use of this promising approach in melanoma and other tumor entities.

Beyond chimerism analysis: methods for tracking a new generation of cell-based medicines

The analysis of chimerism is crucial to determine the status of patients receiving hematopoietic stem cell transplantation. The variety of relevant techniques available today range from those that analyse nucleic acids (i.e. polymerase chain reaction based, next generation sequencing) and cellular phenotype (i.e. flow cytometry) to sophisticated imaging (particularly multimodal imaging using labelling agents). However, current developments of advanced therapies bring chimerism studies into a new dimension in which methods for detection of donor cells in the patient need to adapt to a wider range of cell- and gene-based medicines, routes of administration, target organs and pathologies. Herein we describe and analyze the toolkit of suitable labelling and detection methodologies with actual examples along with a discussion on challenges ahead and potential solutions. Remarkably, existing methods commonly used in chimerism analysis are suitable for use with new cell- and gene-based medicines. Indeed, new developments may facilitate the evolution and combination of such methodologies to the use of non-invasive and highly informative approaches.

Management of Chimeric Antigen Receptor (CAR) T-Cell Toxicities: A Review and Guideline for Emergency Providers

BACKGROUND

Chimeric antigen receptor (CAR) T-cell therapy is an adoptive cellular immunotherapy that is being utilized more frequently due to its initial success in advanced-stage cancers. Unfortunately, CAR T-cell therapy is often associated with acute systemic toxicities, including cytokine release syndrome (CRS) and CAR T-cell-associated neurotoxicity (neurotoxicity).

OBJECTIVE

We created a review that addresses the potential common emergency department (ED) presentations associated with CAR T-cell therapy. We reviewed the relevant research and clinical guidelines to develop a guide tailored toward addressing the needs of the emergency medicine community to manage these complications. In addition, a case is presented and the evaluation and management of CRS and neurotoxicity are reviewed in detail.

DISCUSSION

Despite CAR T-cell designs showing promising results, the risk of acquiring an acute toxicity is high, with CRS and neurotoxicity reported most often. The systemic toxicities associated with these adverse events can lead to end-organ damage and compromise the patient acutely or jeopardize the continuation in treatment of their underlying malignancy. Depending on the severity of the toxicity, treatment typically starts with vigilant supportive care, but may include administration of tocilizumab and possibly high-dose corticosteroids if the toxicity is deemed of high severity.

CONCLUSIONS

With the increasing administration of CAR T-cell therapy, emergency physicians will likely encounter more patients with associated adverse events, including CRS and neurotoxicity. It is increasingly important that emergency physicians are aware of these potential toxicities in order to rapidly diagnose and treat patients undergoing CAR T-cell therapy.

Palliative and End-of-Life Care for Patients With Hematologic Malignancies

Hematologic malignancies are a heterogeneous group of diseases with unique illness trajectories, treatment paradigms, and potential for curability, which affect patients' palliative and end-of-life care needs. Patients with hematologic malignancies endure immense physical and psychological symptoms because of both their illness and often intensive treatments that result in significant toxicities and adverse effects. Compared with patients with solid tumors, those with hematologic malignancies also experience high rates of hospitalizations, intensive care unit admissions, and in-hospital deaths and low rates of referral to hospice as well as shorter hospice length of stay. In addition, patients with hematologic malignancies harbor substantial misperceptions about treatment risks and benefits and frequently overestimate their prognosis. Even survivors of hematologic malignancies struggle with late effects, post-treatment complications, and post-traumatic stress symptoms that can significantly diminish their quality of life. Despite these substantial unmet needs, specialty palliative care services are infrequently consulted for the care of patients with hematologic malignancies. Several illness-specific, cultural, and system-based barriers to palliative care integration and optimal end-of-life care exist in this population. However, recent evidence has demonstrated the feasibility, acceptability, and efficacy of integrating palliative care to improve the quality of life and care of patients with hematologic malignancies and their caregivers. More research is needed to develop and test population-specific palliative and supportive care interventions to ensure generalizability and to define a sustainable clinical delivery model. Future work also should focus on identifying moderators and mediators of the effect of integrated palliative care models on patient-reported outcomes and on developing less resource-intensive integrated care models to address the diverse needs of this population.

Neurotoxicity associated with cancer immunotherapy: immune checkpoint inhibitors and chimeric antigen receptor T-cell therapy

PURPOSE OF REVIEW

Immune checkpoint inhibitors (ICPI) and chimeric antigen receptor T cells (CAR-T) represent novel therapies recently approved to treat a number of human cancers. As both approaches modulate the immune system, they can generate a number of immune-related adverse events (irAEs), including a large spectrum of novel neurological toxicities. These are of special interest given their potential severity and risk of compromising further oncologic treatment. We aim to provide a comprehensive review of the literature and discuss their optimal management.

RECENT FINDINGS

In contrast to irAEs involving other organs, neurological complications of ICPI are uncommon, may present throughout the course of treatment and involve the peripheral and central nervous system, including polyneuropathy, myositis, myasthenia gravis, demyelinating polyradiculopathy, myelitis, encephalitis and others. If started early, ICPI-related neurologic irAEs are usually responsive to steroids. In contrast, as many as 40% of patients undergoing CAR-T therapy will develop neurologic complications in the form of a cytokine-release-associated encephalopathy. It includes delirium, aphasia, tremor/myoclonus, seizure and seizure-like activity.

SUMMARY

irAEs associated with CAR-T and ICPI therapy constitute new entities. Early identification and treatment are essential to optimize the functional outcome and further oncologic management of the patient.

Breast cancer stem cell antigens as targets for immunotherapy

The great success of immunotherapy is paving the way for a new era in cancer treatment and is driving major improvements in the therapy of patients suffering from a range of solid tumors. However, the choice of the appropriate tumor antigens to be targeted with cancer vaccines and T-cell therapies is still a challenge. Most antigens targeted so far have been identified on the tumor bulk and are expressed on differentiated cancer cells. The discovery of a small population of cancer stem cells (CSC), which is refractory to most current therapies and responsible for the development of metastasis and recurrence, has made it clear that the ideal targets for immunotherapies are the antigens that are expressed in CSC and play a key role in their function. Indeed, their immunotargeting would enable the eradication of CSC to be performed, thus eliminating the tumor source. We call these antigens "CSC oncoantigens". Herein, we summarize the controversial nature of breast CSC, discuss why they represent good candidates for cancer immunotherapy, and review the CSC antigens that have been used as targets for CSC immunotargeting this far. Moreover, we describe the pipeline that we have developed for the identification of fresh CSC oncoantigens, and present the pre-clinical results obtained with vaccines that target some of these antigens.

A highly efficient and safe gene delivery platform based on polyelectrolyte core–shell nanoparticles for hard-to-transfect clinically relevant cell types

The polyelectrolyte nanocarriers’ based on nanosized vaterite particles as a novel tool for genetic material delivery into the clinically relevant cell types and potential application of described technology in gene therapy approaches.

PD-1 disrupted CAR-T cells in the treatment of solid tumors: Promises and challenges

Unprecedented efficacy of chimeric antigen receptor (CAR) T cell therapy in the treatment of hematologic malignancies brings new hope for patients with many cancer types including solid tumors. However, the challenges for CAR-T cell therapy in eradicating solid tumors are immense. To overcome these seemingly intractable hurdles, more "powerful" CAR-T cells with enhanced antitumor efficacy are required. Emerging data support that the anti-tumor activity of CAR-T cells can be enhanced significantly without evident toxicity through simultaneous PD-1 disruption by genome editing. This review focuses on the current progress of PD-1 gene disrupted CAR-T cells in cancer therapy. Here we discuss key rationales for this new combination strategy and summarize the available pre-clinical studies. An update is provided on human clinical studies and available registered cancer clinical trials using CAR-T cells with PD-1 disruption. Future prospects and challenges are also discussed.

Chimeric antigen receptor -T cell therapy: Applications and challenges in treatment of allergy and asthma

Despite the current advancements, cancer treatment approaches have limitations restricting their cure rate. Immunotherapy techniques are among novel and promising cancer therapeutic approaches. Therapeutic antibodies and adoptive cell therapy (ACT) are the main branches of immunotherapy. T lymphocytes and genetically engineered cells are among important cells which can be used in ACT. This review has focused on recent advances in engineered cell-based immunotherapy based on T lymphocytes with chimeric antigen receptors (CARs). CARs are recombinant receptors expressing T cell signaling domains with or without co-stimulatory molecules. CAR-T cells are expanded ex vivo and re-infused to patients in order to improve their therapeutic efficacy. Nowadays, the beneficial function of CAR-T cell therapy has been indicated in various diseases including hematological malignancies, solid tumors, autoimmune diseases, and allergic diseases such as asthma. Furthermore, antigen-specific T regulatory cells (T_regs) and gene-edited T cells seem to be beneficial in controlling inflammation in allergic asthma. In fact, dysregulated function of T_regs is responsible for dominance of T helper 2 immune response and progression of allergic asthma. CAR-T_reg cells can also be designed and reproduced using iT_reg population to manage asthma. In addition, universal CAR-T cells can be modified to selectively target multiple antigens. The fourth generation CAR-T cells (i.e. TRUCK cells) represent novel strategies to cure asthma and allergic diseases as well. Despite the advantages of CAR-T cells, their applications can be associated with some unwanted reactions such as cytokine storm, anaphylaxis, neurotoxicity, etc. For clinical application, there is a need to prevent and manage these complications by optimizing ACT protocols.

CAR-T cell therapy in melanoma: A future success story?

Chimeric antigen receptor (CAR)-T cells are one of the impressive recent success stories of anti-cancer immunotherapy. Especially in haematological malignancies, this treatment strategy has shown promising results leading to the recent approval of two CAR-T cell constructs targeting CD19 in the United States and the European Union. After the huge success in haematological cancers, the next step will be the evaluation of its efficacy in different solid tumors, which is currently investigated in preclinical as well as clinical settings. A commonly examined tumor model in the context of immunotherapy is melanoma, since it is known for its immunogenic features. However, the first results of CAR-T cell therapy in solid tumors did not reveal the same impressive outcomes that were observed in haematological malignancies, as engineered cells need to cope with several challenges. Obstacles include the lack of migration of CAR-T cells from blood vessels to the tumor site as well as the immunosuppressive tumor microenvironment within solid tumors. Another hurdle is posed by the identification of an ideal target antigen to avoid on-target/off-tumor toxicities. Regarding immune escape mechanisms, which can be developed by tumor cells to bypass immune recognition, the observation of antigen loss should also be considered. This article gives an overview of the challenges displayed in CAR-T cell therapy for the use in solid tumors and discusses different new strategies and approaches that deal with these problems in order to improve CAR-T cell therapy, particularly for its use in melanoma.

The Role of Interleukin-37 in the Pathogenesis of Allergic Diseases

Cytokines of the interleukin-1 (IL-1) family play an important role in the realization of the protective functions of innate immunity and are the key mediators involved in the pathogenesis of a wide range of diseases, including various manifestations of allergy. The IL-1 family includes more than 11 members. However, the functions of many of them remain to be elucidated. Recently, new members of the IL-1 family have been discovered. In 2000, several independent research groups reported the discovery of a new interleukin of this family, which was named IL-37, or IL-1F7 (according to the new nomenclature). IL-37 was assigned to the IL-1 family based on its structural similarity with other members of this family. The study of its biological properties showed that its activity changes in inflammatory diseases, such as rheumatoid arthritis, psoriasis, as well as allergic diseases (allergic rhinitis, bronchial asthma, and atopic dermatitis). However, unlike most members of the IL-1 family, IL-37 acts as a negative regulator of inflammation. Activation of IL-37 suppresses inflammation, resulting in the suppression of inflammatory cytokines and chemokines, which in turn prevents infiltration of pro-inflammatory cells, mainly eosinophils and neutrophils. The exact molecular and cellular mechanisms of the anti-inflammatory effect of IL-37 in the development of allergic diseases (AD) have not been fully studied. This review summarizes and analyzes the accumulated experimental data on the role of IL-37 in the pathogenesis of AD, such as allergic rhinitis, bronchial asthma, and atopic dermatitis.

DARPins: Promising Scaffolds for Theranostics

Monoclonal antibodies are the classical basis for targeted therapy, but the development of alternative binding proteins has made it possible to use non-immunoglobulin proteins as targeting modules. The advantages of DARPins, scaffold proteins based on ankyrin repeats, over antibodies are as follows: small size, stability over a wide range of temperatures and pH values, low aggregation tendency, and ease of production in heterologous expression systems. The differences in the structure of the paratope of DARPin and antibodies broaden the spectrum of target molecules, while the ease of creating hybrid fusion proteins allows one to obtain bispecific and multivalent constructs. In this article, we summarize recent data on the development of therapeutic and imaging compounds based on DARPins.

The Other Side of CAR T-Cell Therapy: Cytokine Release Syndrome, Neurologic Toxicity, and Financial Burden

Immune effector cells, including T cells and natural killer cells, which are genetically engineered to express a chimeric antigen receptor (CAR), constitute a powerful new class of therapeutic agents to treat patients with hematologic malignancies. Several CAR T-cell trials have shown impressive remission rates in patients with relapsed/refractory hematologic cancers. Although the clinical responses of these agents in hematologic malignancies have been very encouraging, they have also produced substantial morbidity and occasionally mortality resulting from toxicity. With more experience and collaboration, hopefully the toxicities and the costs will come down, increasing the availability of CAR T cells to patients in need.

Cancer stem cell immunology and immunotherapy: Harnessing the immune system against cancer's source

Despite recent advances in diagnosis and therapy having improved cancer outcome, many patients still do not respond to treatments, resulting in the progression or relapse of the disease, eventually impairing survival expectations. The limited efficacy of therapy is often attributable to its inability to affect cancer stem cells (CSCs), a small population of cells resistant to current radio- and chemo-therapies. CSCs are characterized by self-renewal and tumor-initiating capabilities, and function as a reservoir for the local and distant recurrence of the disease. Therefore, new therapeutic approaches able to effectively target and deplete CSCs are urgently needed. Immunotherapy is facing a renewed interest for its potential in cancer treatment, and the possibility of harnessing the immune system to target CSCs is being addressed by a new exciting research field. In this chapter, we discuss the cancer stem cell model and illustrate CSC biological and molecular properties, critically addressing theoretical and practical issues linked with their definition and study. We then review the existing literature regarding the immunological properties of CSCs and the complex interplay occurring between CSCs and immune cells. Finally, we present up-to-date studies on CSC immunotargeting and its potential future perspective. In conclusion, understanding the interplay between CSC biology and tumor immunology will provide a deeper understanding of the mechanisms that regulate CSC immunological properties. This will contribute to the design of new CSC-directed immunotherapeutic strategies with the potential of strongly improving cancer outcomes.

Improving Immunotherapy Through Glycodesign

Immunotherapy is revolutionizing health care, with the majority of high impact "drugs" approved in the past decade falling into this category of therapy. Despite considerable success, glycosylation-a key design parameter that ensures safety, optimizes biological response, and influences the pharmacokinetic properties of an immunotherapeutic-has slowed the development of this class of drugs in the past and remains challenging at present. This article describes how optimizing glycosylation through a variety of glycoengineering strategies provides enticing opportunities to not only avoid past pitfalls, but also to substantially improve immunotherapies including antibodies and recombinant proteins, and cell-based therapies. We cover design principles important for early stage pre-clinical development and also discuss how various glycoengineering strategies can augment the biomanufacturing process to ensure the overall effectiveness of immunotherapeutics.

Comparative analysis and optimization of protocols for producing recombinant lentivirus carrying the anti-Her2 chimeric antigen receptor gene

BACKGROUND

The production of anti-Her2 chimeric antigen receptor (CAR) T cells needs to be optimized to make it a reliable therapy.

METHODS

Three types of lentiviral vectors expressing anti-Her2 CAR together with packaging plasmids were co-transfected into 293 T-17 cells. The vector with the best packaging efficiency was selected, and the packaging cell culture system and packaging plasmid system were optimized. Centrifugation speed was optimized for the concentration of lentivirus stock. The various purification methods used included membrane filtration, centrifugation with a sucrose cushion and the novelly-designed instantaneous high-speed centrifugation. The recombinant lentiviruses were transduced into human peripheral T cells with an optimized multiplicity of infection (MOI). CAR expression levels by three vectors and the efficacy of CAR-T cells were compared.

RESULTS

When co-transfected, packaging cells in suspension were better than the commonly used adherent culture condition, with the packaging system psPAX2/pMD2.G being better than pCMV-dR8.91/pVSV-G. The optimal centrifugation speed for concentration was 20 000 g, rather than the generally used ultra-speed. Importantly, adding instantaneous centrifugation for purification significantly increased human peripheral T cell viability (from 13.25% to 62.80%), which is a technical breakthrough for CAR-T cell preparation. The best MOI value for transducing human peripheral T cells was 40. pLVX-EF1a-CAR-IRES-ZsGreen1 expressed the highest level of CAR in human peripheral T cells and the cytotoxicity of CAR-T cells reached 63.56%.

CONCLUSIONS

We optimized the preparation of recombinant lentivirus that can express third-generation anti-Her2 CAR in T cells, which should lay the foundation for improving the efficacy of CAR-T cells with respect to killing target cells.

Chimeric Antigen Receptor T-Cells (CAR T-Cells) for Cancer Immunotherapy - Moving Target for Industry?

The first CD19 CAR T-cell products, Kymriah and Yescarta, are entering the US market and also being evaluated for marketing authorization in the EU. This breakthrough has expanded the interest and also investments towards novel chimeric antigen receptor (CAR) designs, both for hematological malignancies and solid tumors. At the same time, there is active development in moving from autologous products to allogeneic, off-the-shelf -products. New manufacturing technologies are also emerging for production of these complex genetically-modified cells and even decentralized manufacturing in hospitals is under consideration. However, the high potency of CAR T-cells is associated with toxicity and not all patients respond to the treatment. In addition, the number of patient and product variables impacting the clinical outcome is high. The race towards novel CAR T treatment options for cancer patients has begun, but without careful design of the constructs and overall understanding of the factors that impact the ultimate outcome in each case, the road towards commercial success may be long and winding. This review discusses the product- and patient-related variables that may pose challenges for the industry and developers both from the scientific and regulatory perspective.

Ethical Guidance for Selecting Clinical Trials to Receive Limited Space in an Immunotherapy Production Facility

Our aims are to (1) set forth a multiprinciple system for selecting among clinical trials competing for limited space in an immunotherapy production facility that supplies products under investigation by scientific investigators; (2) defend this system by appealing to justice principles; and (3) illustrate our proposal by showing how it might be implemented. Our overarching aim is to assist manufacturers of immunotherapeutic products and other potentially breakthrough experimental therapies with the ethical task of prioritizing requests from scientific investigators when production capacity is limited.

Anti-GD2/4-1BB chimeric antigen receptor T cell therapy for the treatment of Chinese melanoma patients

Background

Chimeric antigen receptor (CAR)-engineered T cells have demonstrated promising clinical efficacy in patients with B cell lymphoma. However, the application of CAR-T cell therapy in the treatment of other solid tumors has been limited. We incorporated 4-1BB into the anti-GD2 CAR-T cells to test their cytotoxicity in melanoma in vitro and in vivo. Moreover, we reported the expression of ganglioside GD2 in non-Caucasian melanoma populations for the first time, thus providing a basis for future clinical research.

Methods

This study included tumor samples from 288 melanoma patients at the Peking University Cancer Hospital & Institute. Clinical data were collected. Immunohistochemical assays using antibodies against ganglioside GD2 were performed on formalin-fixed, paraffin-embedded specimens. The ability of ganglioside GD2 CAR-T cells to kill ganglioside GD2⁺ melanoma cells was evaluated in vitro and in a patient-derived xenograft (PDX) model.

Results

Among the 288 samples, 49.3% of cases (142/288) demonstrated positive staining with ganglioside GD2. The median survival time in patients exhibiting ganglioside GD2 expression was significantly shorter than that in patients without ganglioside GD2 expression (31 vs. 47.1 months, P < 0.001). In the present study, CAR was constructed using a GD2-specific scFv (14.G2a), T cell receptor CD3ζ chain, and the CD137 (4-1BB) costimulatory motif. In addition, the GD2.BBζ CAR-T cells demonstrated specific lysis of ganglioside GD2-expressing melanoma cells in vitro. In two PDX models, mice that received intravenous or local intratumor injections of GD2.BBζ CAR-T cells experienced rapid tumor regression.

Conclusions

These data demonstrate that the rate of GD2 expression in Chinese patients is 49.3%. GD2.BBζ CAR-T cells can both efficiently lyse melanoma in a GD2-specific manner and release Th1 cytokines in an antigen-dependent manner in vitro and in vivo. Anti-GD2/4-1BB CAR-T cells represent a clinically appealing treatment strategy for Chinese melanoma patients exhibiting GD2 expression and provide a basis for future studies of the clinical application of immunotherapy for melanoma.

Electronic supplementary material

The online version of this article (10.1186/s13045-017-0548-2) contains supplementary material, which is available to authorized users.

Genetic Modification of T Cells with Chimeric Antigen Receptors: A Laboratory Manual

Redirected T cells genetically modified with a chimeric antigen receptor (CAR) have induced spectacular remissions of refractory leukemia/lymphoma in early phase trials, attracting interest to use CAR T cells in a variety of other applications including solid cancer and nonmalignant diseases. However, extensive preclinical explorations demand highly effective and robust procedures for the genetic modification of blood T cells; the same applies for engineering with a recombinant T cell receptor. We present laboratory procedures in a step-by-step protocol to engineer human and mouse T cells with a CAR by γ-retro- or lentiviral transduction for further preclinical testing.

Gene therapy: advances, challenges and perspectives

The ability to make site-specific modifications to the human genome has been an objective in medicine since the recognition of the gene as the basic unit of heredity. Thus, gene therapy is understood as the ability of genetic improvement through the correction of altered (mutated) genes or site-specific modifications that target therapeutic treatment. This therapy became possible through the advances of genetics and bioengineering that enabled manipulating vectors for delivery of extrachromosomal material to target cells. One of the main focuses of this technique is the optimization of delivery vehicles (vectors) that are mostly plasmids, nanostructured or viruses. The viruses are more often investigated due to their excellence of invading cells and inserting their genetic material. However, there is great concern regarding exacerbated immune responses and genome manipulation, especially in germ line cells. In vivo studies in in somatic cell showed satisfactory results with approved protocols in clinical trials. These trials have been conducted in the United States, Europe, Australia and China. Recent biotechnological advances, such as induced pluripotent stem cells in patients with liver diseases, chimeric antigen receptor T-cell immunotherapy, and genomic editing by CRISPR/Cas9, are addressed in this review.