Reengineering chimeric antigen receptor T cells for targeted therapy of autoimmune disease

The Evolution of Anti-CD20 Treatment for Multiple Sclerosis: Optimization of Antibody Characteristics and Function

B-cell depletion with CD20-targeted agents is commonly used for treatment of multiple sclerosis (MS), other autoimmune diseases, and certain hematologic malignancies. Initial apparent success with rituximab in MS and neuromyelitis optica spurred development of the anti-CD20 monoclonal antibody (mAb) therapies ocrelizumab, ofatumumab, and ublituximab as well as the anti-CD19 mAb inebilizumab. While each are effective at targeting and depleting B cells, structural differences translate into different mechanisms of action affecting maintenance of B-cell depletion and safety and tolerability. Although the anti-CD20 mAbs differ in degree of human versus mouse sequences as well as target CD20 epitope, these properties do not appear to substantially affect activity or tolerability. In contrast, an antibody-dependent cell-mediated cytotoxicity (ADCC) versus a complement-dependent cytotoxicity mechanism of action as well as subcutaneous versus intravenous administration may provide improved tolerability. Glycoengineering of the mAbs ublituximab and inebilizumab enhances ADCC and can overcome the reduced responses to mAb-mediated B-cell depletion associated with certain genetic polymorphisms. Other strategies for therapeutic targeting of CD20, including brain shuttle antibodies (e.g., RO7121932), bispecific antibodies, chimeric antigen receptor T-cell therapies, and antibody-drug conjugates, are in active clinical development and may be future treatment approaches in MS and other B-cell-mediated autoimmune diseases.

CAR T-cell therapy in autoimmune diseases: where are we and where are we going?

Chimeric antigen receptor (CAR)-based therapies developed for the treatment of haematological malignancies have recently been repurposed to treat refractory systemic autoimmune diseases. In this Review we critically discuss the current data available on the use of CAR-based therapy in systemic autoimmune diseases, the current challenges, and the potential next steps toward their implementation into clinical practice. Beyond the targeting of B cells via CD19, we discuss the advantages and potential pitfalls of targeting plasma cells (B-cell Maturation Antigen or CD138) and other non-immune targets, such as fibroblast activated protein, and of aiming to restore immune homeostasis using CAR T regulatory cells. Crucial points need to be addressed for CAR-based therapy to become a viable treatment option for patients with systemic autoimmune diseases.

Cellular therapies in rheumatic and musculoskeletal diseases

A substantial proportion of patients diagnosed with rheumatologic and musculoskeletal diseases (RMDs) exhibit resistance to conventional therapies or experience recurrent symptoms. These diseases, which include autoimmune disorders such as multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematosus, are marked by the presence of autoreactive B cells that play a critical role in their pathogenesis. The persistence of these autoreactive B cells within lymphatic organs and inflamed tissues impairs the effectiveness of B-cell-depleting monoclonal antibodies like rituximab. A promising therapeutic approach involves using T cells genetically engineered to express chimeric antigen receptors (CARs) that target specific antigens. This strategy has demonstrated efficacy in treating B-cell malignancies by achieving long-term depletion of malignant and normal B cells. Preliminary data from patients with RMDs, particularly those with lupus erythematosus and dermatomyositis, suggest that CAR T-cells targeting CD19 can induce rapid and sustained depletion of circulating B cells, leading to complete clinical and serological responses in cases that were previously unresponsive to conventional therapies. This review will provide an overview of the current state of preclinical and clinical studies on the use of CAR T-cells and other cellular therapies for RMDs. Additionally, it will explore potential future applications of these innovative treatment modalities for managing patients with refractory and recurrent manifestations of these diseases.

Revolutionizing Autoimmune Kidney Disease Treatment with Chimeric Antigen Receptor-T Cell Therapy

Autoimmune kidney diseases (AIKDs) depict a range of disorders involving immune-mediated damage to the kidneys, where conventional biologic therapies involving monoclonal antibodies often prove insufficient because of persistent autoreactive B cell reservoirs in lymphoid organs and inflammatory tissues. The appearance of chimeric antigen receptor (CAR)-T cell therapies targeting B cells has shown transformative potential, with recent clinical trials showing the remarkable efficacy of anti-CD19 CAR-T cells in achieving profound B cell depletion, reducing immune complex deposition, and ameliorating renal inflammation in AIKDs. While these results highlight the potential of CAR-T cell therapy in facilitating immune reset and overcoming treatment resistance, further clinical investigations are imperative to establish its long-term safety and sustained therapeutic benefits. This review synthesizes current evidence on CAR-T cell applications in AIKDs, discusses critical considerations for clinical translation, identifies existing limitations and challenges, and proposes strategic directions for therapeutic optimization and advancement.

Chimeric Autoantibody Receptor- and/or Peptide-MHC-Based CAR Therapies for Targeted Elimination of Antigen-Specific B or T Cells in Hypersensitivity Disorders Such as Allergies and Autoimmune Diseases

Hypersensitivity reactions are dysregulated and potentially devastating immune responses, characterized by a tendency to become chronic. They target either self-proteins or harmless foreign proteins and are driven by both T and B cells. Although numerous symptomatic treatment options for hypersensitivity reactions have been established over recent decades, only a few antigen-specific, causal approaches capable of specifically targeting the pathogenic autoreactive T and/or B cells have been developed. Among these are cell-based treatment modalities involving chimeric antigen receptor (CAR)- or chimeric autoantibody-receptor (CAAR)-expressing cells. These therapies utilize B- or T-cell antigens, presented as B-cell epitopes or peptide-major histocompatibility complexes (pMHCs) to serve as bait. The latter are coupled to potent activation domains derived from the TCR/CD3 complex itself, such as the zeta or CD3 chains, as well as domains from bona fide co-stimulatory molecules (e.g., CD28, 4-1BB). Recent in vitro and in vivo studies have demonstrated the therapeutic potential of these ATMP-based strategies in eliminating autoreactive lymphocytes and alleviating hypersensitivity reactions. This systematic review provides a comprehensive overview of the current status of antigen-specific CAR and CAAR T-cell therapies, highlighting novel directions as well as the ongoing challenges within this promising research field.

New thoughts on the intestinal microbiome-B cell-IgA axis and therapies in IgA nephropathy

IgA nephropathy (IgAN), as the most common chronic glomerulonephritis worldwide, is often triggered by mucosal infections and follows a chronic progression, with the majority of patients ultimately progressing to end-stage renal disease (ESRD) during their lifetimes. Since the mystery of its complete pathogenesis has not been fully solved, the resulting lack of effective early diagnosis and treatment greatly affects the prognosis of patients. Given the well-defined pathological feature of IgA deposition in the mesangial region, the source and role of pathogenic IgA has been focused on. Starting from the microbiology and immunity of the gut, we systematically review both the physiological and the pathological process of microbiome-B cell-IgA axis, from microbial-induced IgA production to the role of IgA in the intestinal immune milieu, and ultimately end up with the various aspects of microbiome-B cell-IgA axis in the pathogenesis of IgAN as well as the corresponding therapeutic initiatives available. Our retrospective review helps researchers to systematically understand the complex role between intestinal flora dysbiosis and pathogenic IgA in IgAN. This understanding provides a foundation for in-depth explorations to uncover more detailed pathogenic mechanisms and to develop more precise and effective diagnostic and therapeutic approaches.

Lipid nanoparticle (LNP) mediated mRNA delivery in neurodegenerative diseases

Neurodegenerative diseases (NDD) are characterized by the progressive loss of neurons and the impairment of cellular functions. Messenger RNA (mRNA) has emerged as a promising therapy for treating NDD, as it can encode missing or dysfunctional proteins and anti-inflammatory cytokines or neuroprotective proteins to halt the progression of these diseases. However, effective mRNA delivery to the central nervous system (CNS) remains a significant challenge due to the limited penetration of the blood-brain barrier (BBB). Lipid nanoparticles (LNPs) offer an efficient solution by encapsulating and protecting mRNA, facilitating transfection and intracellular delivery. This review discusses the pathophysiological mechanisms of neurological disorders, including Parkinson's disease (PD), Alzheimer's disease (AD), multiple sclerosis (MS), Huntington's disease (HD), ischemic stroke, spinal cord injury, and Friedreich's ataxia. Additionally, it explores the potential of LNP-mediated mRNA delivery as a therapeutic strategy for these diseases. Various approaches to overcoming BBB-related challenges and enhancing the delivery and efficacy of mRNA-LNPs are discussed, including non-invasive methods with strong potential for clinical translation. With advancements in artificial intelligence (AI)-guided mRNA and LNP design, targeted delivery, gene editing, and CAR-T cell therapy, mRNA-LNPs could significantly transform the treatment landscape for NDD, paving the way for future clinical applications.

Chimeric autoantibody receptor T cells clonally eliminate B cells producing autoantibodies against IFN-γ

Neutralizing anti-interferon-γ (IFN-γ) autoantibodies (nAIGAs) impair IFN-γ-mediated immunity, predisposing patients with nAIGAs to infection by nontuberculous mycobacteria, Talaromyces marneffei, and other intracellular pathogens. Current clinical management relies on continuous antimicrobial therapy, with no treatment offering sustained benefits. Here, we developed human chimeric autoantibody receptor (CAAR) T cells targeting autoreactive B cells expressing nAIGA B cell receptors (BCRs) using an IFN-γ receptor-irresponsive IFN-γ variant as bait. By exploiting a mouse model of nAIGA BCR-expressing B cell leukemia, we found that IFN-γ CAAR T cells lack off-target toxicity, including IFN-γ receptor cross-reactive toxicity and Fc-redirected toxicity. IFN-γ CAAR T cells substantially reduced circulating AIGAs secreted from target cells in vivo. Further, IFN-γ CAAR T cells effectively eliminated autoreactive B cells in ex vivo cultures of peripheral blood mononuclear cells from patients with nAIGAs. Together, these results demonstrate that IFN-γ CAAR T cells may be a promising strategy to ameliorate nAIGA-associated infections by eliminating autoreactive B cells.

Engaging T cells for cleanup

T-cell engagers represent a transformative approach to cancer immunotherapy leveraging bispecific and multispecific antibody constructs to redirect T-cell cytotoxicity toward malignant cells. These molecules bridge T cells and tumor cells by simultaneously binding CD3 on T cells and tumor-associated antigens on cancer cells, thereby enabling precise immune targeting even in immunologically "cold" tumors. Recent advancements include conditional T-cell engagers activated by tumor microenvironment proteases to minimize off-tumor toxicity as well as T-cell receptor-based engagers targeting intracellular antigens via MHC presentation. Clinical successes, such as Kimmtrak in metastatic uveal melanoma, underscore good potential of these modalities, while challenges persist in the management of cytokine release syndrome, neurotoxicity, and tumor resistance. Emerging multispecific engagers are aimed at enhancing efficacy via incorporation of costimulatory signals, thus offering a promising trajectory for next-generation immunotherapies. T-cell engagers are also gaining attention in the treatment of autoimmune disorders, where they can be designed to selectively modulate pathogenic immune responses. By targeting autoreactive T or B cells, T-cell engagers hold promise for restoring immune tolerance in such conditions as HLA-B*27-associated autoimmunity subtypes, multiple sclerosis, rheumatoid arthritis, and type 1 diabetes mellitus. Engineering strategies that incorporate inhibitory receptors or tissue-specific antigens may further refine T-cell engagers' therapeutic potential in autoimmunity, by minimizing systemic immunosuppression while preserving immune homeostasis.

Current and emerging therapies for autoimmune encephalitis

INTRODUCTION

Autoimmune encephalitis (AIE) is an inflammatory neurological disorder often associated with autoantibodies targeting neural or glial antigens. Patients with AIE are often treated with immunotherapy, but multiple questions remain about the optimal treatment strategy for common AIE subtypes.

AREAS COVERED

The authors conducted a literature search of PubMed articles and Google Scholar articles using keywords 'autoimmune encephalitis,' 'anti-NMDA receptor encephalitis, 'LG1 encephalitis' from 2005 to 2024. This review briefly outlines the proposed pathophysiology of AIE with autoantibodies toward cell surface vs intracellular antigens. Next, the authors discuss treatments commonly used for AIE, and provide guidance on side effects and monitoring, and the evidence for treatment approaches for anti-NMDAr and LGI1 encephalitis is reviewed. In the final section, an overview of ongoing clinical trials and future therapies for AIE is provided.

EXPERT OPINION

Patients with AIE benefit from treatment with immunotherapy, but the evidence supporting specific treatment strategies is limited to observational studies. Successful clinical trials for AIE will provide new therapy options for patients, and the next generation of therapies may provide more targeted approaches to treating the condition.

Cell Therapy and the Skin: Great Potential but in Need of Optimization

Cell therapy is rapidly growing owing to its therapeutic potential for diseases with currently poor outcomes. Cell therapy encompasses both nonengineered and engineered cells and possesses unique abilities such as sense-and-respond functions and long-term engraftment for persistent curative potential. Cell therapy capabilities have expanded to address a wide spectrum of diseases, and our review is focused on dermatological applications. The use of fibroblasts and keratinocytes as cell therapy has shown promise in skin disorders such as epidermolysis bullosa. Future efforts include testing the ability of fibroblasts to reprogram nonvolar to volar skin to reduce stump dermatoses in patients with limb loss using prosthetics.

Newer B-cell and plasma-cell targeted treatments for rituximab-resistant patients with membranous nephropathy

Membranous nephropathy is the most common cause of nephrotic syndrome in adults. While spontaneous remission occurs in approximately one-third of cases, another one-third of patients receiving immunosuppressive therapy demonstrate treatment resistance. This resistance, coupled with persistent proteinuria, significantly increases the risk of kidney failure. Alternative therapies, including B-cell and plasma-cell targeted treatments have been explored in isolated cases and case series. In this review, we examine the available evidence on the treatment of resistant and relapsing membranous nephropathy with a particular focus on B- and plasma-cell directed therapies.

CAR-T cell therapy in rheumatic diseases: a review article

CAR-T cell therapy, a pioneering immune-modulating treatment that was initially designed for hematologic malignancies, is now being considered a potential treatment for autoimmune and rheumatic diseases. This method involves genetically engineering T cells to express chimeric antigen receptors (CARs), allowing them to target specific antigens associated with pathogenic immune cells. The review covers the possibility of CAR-T therapy in the treatment of autoimmune diseases like systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc). The therapy's ability to maintain remission by targeting autoreactive B cells in the course of disease has been an important aspect of studies involving SLE. In refractory RA, CAR-T cells also demonstrate a potential therapeutic modality in selectively killing immune cells driving the disease process. For SSc, CAR-T therapy may represent a novel therapeutic approach because it targets the dysregulated activity of B cells as well as the fibrotic processes that drive the disease pathology. Emerging evidence suggests potential applications in conditions such as Sjögren's syndrome and dermatomyositis. While CAR-T therapy promises accuracy, persistence, and the potential for long-term remission, many problems remain, including the risk of cytokine release syndrome, immune toxicity, and treatment affordability. The development of CAR-Tregs and advanced gene-editing techniques may increase the specificity and safety of therapy. In addition, clinical trials and long-term studies should be conducted to establish the efficacy, safety, and economic feasibility of this innovative approach. This review underscores the transformative potential of CAR-T therapy in the management of rheumatic diseases, particularly in refractory cases. Offering targeted immunomodulation with a minimum of systemic immune suppression, CAR-T therapy could redefine therapeutic paradigms and offer hope for improved outcomes in autoimmune diseases.

CAR T cells in autoimmunity: game changer or stepping stone?

ABSTRACT

The advent of chimeric antigen receptor (CAR) T cells has revolutionized the treatment landscape for hematologic malignancies, and emerging evidence suggests their potential in autoimmune diseases (AIDs). This article evaluates the early successes and future implications of B-cell-targeting CAR T-cell therapy in AIDs. Initial applications, particularly in refractory systemic lupus erythematosus, have demonstrated significant and durable clinical remissions, with accompanying evaluation of the immune system suggesting a so-called "reset" of innate inflammation and adaptive autoimmunity. This has generated widespread interest in expanding this therapeutic approach. CAR T cells offer unique advantages over other treatment modalities, including very deep B-cell depletion and unique therapeutic activity within inflamed tissues and associated lymphoid structures. However, the field must address key concerns, including long-term toxicity, particularly the risk of secondary malignancies, and future accessibility given the higher prevalence of AIDs compared with malignancies. Technological advances in cell therapy, such as next-generation CAR T cells, allogeneic off-the-shelf products, and alternative cell types, such as regulatory CAR T cells, are being explored in AIDs to improve efficacy and safety. In addition, bispecific antibodies are emerging as potential alternatives or complements to CAR T cells, potentially offering comparable efficacy without the need for complex logistics, lymphodepletion, and the risk of insertional mutagenesis. As the field evolves, cellular therapists will play a critical role in the multidisciplinary teams managing these complex cases. The transformative potential of CAR T cells in AIDs is undeniable, but careful consideration of safety, efficacy, and implementation is essential as this novel therapeutic approach moves forward.

The road ahead for chimeric antigen receptor T cells

Chimeric antigen receptor T (CART) cell therapy is an innovative form of immunotherapy that has shown remarkable and long-term responses in patients with B-cell malignancies. Over the years, the field has made significant progress in our understanding of the successes and challenges associated with CART cell therapy. In this review, we provide an overview of the current state of CART cell therapy in the clinic. We detail current challenges including patient access, CART-associated toxicity, tumor heterogeneity, CART cell trafficking, the tumor microenvironment, and different CART cell fates. With each challenge, we review lessons learned, potential solutions and outline areas for future development. Finally, we discuss how the field of engineered cell therapy is moving into the treatment of solid tumors and other diseases beyond cancer.

Expanding the CAR toolbox with high throughput screening strategies for CAR domain exploration: a comprehensive review

Chimeric antigen receptor (CAR)-T-cell therapy has been highly successful in the treatment of B-cell hematological malignancies. CARs are modular synthetic molecules that can redirect immune cells towards target cells with antibody-like specificity. Despite their modularity, CARs used in the clinic are currently composed of a limited set of domains, mostly derived from IgG, CD8α, 4-1BB, CD28 and CD3ζ. The current low throughput CAR screening workflows are labor-intensive and time-consuming, and lie at the basis of the limited toolbox of CAR building blocks available. High throughput screening methods facilitate simultaneous investigation of hundreds of thousands of CAR domain combinations, allowing discovery of novel domains and increasing our understanding of how they behave in the context of a CAR. Here we review the growing body of reports that employ these high throughput screening and computational methods to advance CAR design. We summarize and highlight the important differences between the different studies and discuss their limitations and future considerations for further improvements. In conclusion, while still in its infancy, high throughput screening of CARs has the capacity to vastly expand the CAR domain toolbox and improve our understanding of CAR design. This knowledge could be foundational for translating CAR therapy beyond hematological malignancies and push the frontiers in personalized medicine.

Chimeric autoantibody receptor T cells specifically eliminate Graves' Disease autoreactive B cells

Introduction

Chimeric antigen receptor (CAR) T cells have recently become an important treatment for hematological cancers by efficiently eliminating B cells. B cell depleting CAR T cells are also in clinical trials for their use in treating severe autoimmune diseases and have shown promise in patients who have exhausted other treatment options; however, they do result in immunosuppression due to B cell depletion. Specifically eliminating the disease-causing B cells while leaving the healthy B cells untouched could address this limitation.

Methods

A chimeric autoantibody receptor (CAAR) has an autoantigen as the binding domain of the CAR T cell and could allow for specific targeting of autoreactive B cell populations. In Graves' Disease (GD), pathogenesis is centered around autoreactive B cells which are specific for thyroid stimulating hormone receptor (TSHR). By engineering epitopes of TSHR as the binding domain, our CAAR was able to bind to anti-TSHR antibodies and B cell receptors.

Results

These TSHR CAAR T cells specifically eliminated anti-TSHR B cells, without exhibiting cytotoxicity against healthy B cells. We hypothesized that soluble autoantibodies and thyroid stimulating hormone (TSH) could bind to the CAAR, potentially causing overactivation or inhibition. When evaluated, we found that one construct was significantly impacted by soluble autoantibodies, while the other construct was uninhibited. Soluble TSH did not significantly affect either construct. The TSHR CAAR T cells were also effective at eliminating anti-TSHR B cells in the presence of plasma from various GD patients.

Discussion

Thus, TSHR CAAR T cells show promise in eliminating the disease-causing autoreactive B cells in GD without eliminating healthy cells. This treatment mechanism also has the potential to be used in other B cell-mediated autoimmune diseases.

Immune mediated inflammatory diseases: moving from targeted biologic therapy, stem cell therapy to targeted cell therapy

Despite the advancements in targeted biologic therapy for immune-mediated inflammatory diseases (IMIDs), significant challenges persist, including challenges in drug maintenance, primary and secondary non-responses, and adverse effects. Recent data have strengthened the evidence supporting stem cell therapy as an experimental salvage therapy into a standard treatment option. Recent preclinical and clinical studies suggested that chimeric antigen receptor T cell (CAR-T) therapy, which depleting tissue and bone marrow B cells, may lead to improvement, even inducing long-lasting remissions for patients with IMIDs. In this review, we address the unmet needs of targeted biologic therapy, delineate the critical differences between stem cell transplantation and CAR-T therapy, evaluate the current status of CAR-T therapy for IMIDs and explore its potential and existing limitations.

Diverse potential of chimeric antigen receptor-engineered cell therapy: Beyond cancer

BACKGROUND

Chimeric antigen receptor (CAR)-engineered cell therapies have made significant progress in haematological cancer treatment. This success has motivated researchers to investigate its potential applications in non-cancerous diseases, with substantial strides already made in this field.

MAIN BODY

This review summarises the latest research on CAR-engineered cell therapies, with a particular focus on CAR-T cell therapy for non-cancerous diseases, including but not limited to infectious diseases, autoimmune diseases, cardiac diseases and immune-mediated disorders in transplantation. Additionally, the review discusses the current obstacles that need to be addressed for broader clinical applications.

CONCLUSION

With ongoing research and continuous improvements, CAR-engineered cell therapy holds promise as a potent tool for treating various diseases in the future.

KEY POINTS

CAR-engineered cell therapy has expanded beyond cancer to treat autoimmune diseases, infections, cardiac diseases, and transplant-related rejection. The CAR platform is diverse, with various cell types such as CAR-T, CAR-NK, and CAR-M potentially suited for different disease contexts. The safety, efficacy, and practicality of CAR cell therapy in non-cancer diseases remain challenging, requiring further technological optimization and clinical translation.

Precision Reimagined: CRISPR and Multiomics Transform Systemic Lupus Erythematosus Diagnosis and Therapy

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder with diverse clinical manifestations and unpredictable progression, posing significant challenges to accurate diagnosis and effective treatment. Traditional biomarkers and treatments often fail to address the disease's molecular and clinical heterogeneity. Recent advancements in CRISPR gene-editing technology and multiomics approaches offer transformative opportunities for personalized SLE care by unraveling its underlying molecular complexity and enabling precise therapeutic interventions. CRISPR technology allows targeted editing of SLE-associated genetic mutations, addressing disease drivers directly, while multiomics-including genomics, transcriptomics, and proteomics-provides insights into dysregulated immune networks, identifying biomarkers and therapeutic targets. Integrating these approaches can refine patient stratification and enhance the precision of treatments. Artificial intelligence (AI) complements these technologies by synthesizing high-dimensional data, enabling personalized treatment plans, predicting disease trajectories, and optimizing therapeutic strategies. However, the integration of CRISPR and multiomics in clinical settings raises challenges, including technical limitations, ethical concerns, and economic barriers. Emerging clinical trials and case studies demonstrate the potential of these innovations to personalize care and improve outcomes. Nonetheless, the transition from experimental research to routine clinical application requires robust regulatory frameworks and strategies to address these challenges. This review aims to explore the potential of CRISPR and multiomics technologies to revolutionize SLE diagnosis and therapy, emphasizing their integration with AI to advance personalized care. By addressing existing barriers, the review envisions a future where precision medicine transforms SLE management, paving the way for individualized, patient-centered autoimmune therapy.

Chimeric anti-HLA antibody receptor engineered human regulatory T cells suppress alloantigen-specific B cells from pre-sensitized transplant recipients

Organ transplantation is a lifesaving procedure, with 50,000 transplants happening every year in the United States. However, many patients harbor antibodies and B cells directed against allogeneic human leukocyte antigen (HLA) molecules, notably HLA-A2, greatly decreasing their likelihood of receiving a compatible organ. Moreover, antibody-mediated rejection is a significant contributor to chronic transplant rejection. Current strategies to desensitize patients non- specifically target circulating antibodies and B cells, resulting in poor efficacy and complications. Regulatory T cells (Tregs) are immune cells dedicated to suppressing specific immune responses by interacting with both innate and adaptive immune cells. Here, we genetically modified human Tregs with a chimeric anti-HLA antibody receptor (CHAR) consisting of an extracellular HLA-A2 protein fused to a CD28-CD3zeta intracellular signaling domain, driving Treg activation upon recognition of anti-HLA-A2 antibodies on the surface of alloreactive B cells. We find that HLA-A2 CHAR Tregs get activated specifically by anti-HLA-A2 antibody-producing cells. Of note, HLA-A2 CHAR activation does not negatively affect Treg stability, as measured by expression of the Treg lineage transcription factors FOXP3 and HELIOS. Interestingly, HLA-A2 CHAR Tregs are not cytotoxic towards anti-HLA-A2 antibody-producing cells, unlike HLA-A2 CHAR modified conventional CD4 + T cells. Importantly, HLA-A2 CHAR Tregs recognize and significantly suppress high affinity IgG antibody production by B cells from HLA-A2 sensitized patients. Altogether, our results provide proof-of-concept of a new strategy to specifically inhibit alloreactive B cells to desensitize transplant recipients.

Comparative Evaluation of Bleomycin- and Collagen-V-Induced Models of Systemic Sclerosis: Insights into Fibrosis and Autoimmunity for Translational Research

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by fibrosis, immune dysregulation, and vascular dysfunction, yet its pathogenesis remains incompletely understood. This study compares two widely used animal models of SSc-the bleomycin-induced fibrosis model and the collagen-V-induced autoimmune model-to evaluate their ability to replicate key disease features. In the bleomycin model, consistent cardiac fibrosis was observed across treatment groups despite variability in fibrosis in the skin and lungs, suggesting organ-specific differences in susceptibility. The collagen-V model demonstrated robust autoantibody production against collagen-V, confirming its utility in studying immune activation, though fibrosis was largely confined to the heart. While the bleomycin model excels at mimicking rapid fibrosis and is suitable for testing antifibrotic therapies, the collagen-V model provides insights into antigen-specific autoimmunity. Both models highlight the dynamic nature of fibrosis, where ECM deposition and degradation occur concurrently, complicating its use as a quantitative disease marker. Cardiac fibrosis emerged as a consistent feature in both models, emphasizing its relevance in SSc pathophysiology. Combining these models or refining their design through hybrid approaches, extended timelines, or sex and age adjustments could enhance their translational utility. These findings advance understanding of SSc mechanisms and inform therapeutic development for this challenging disease.

Depletion of alloreactive B cells by drug-resistant chimeric alloantigen receptor T cells to prevent transplant rejection

Antibody-mediated rejection (AMR) remains a major complication after solid organ transplantation (SOT). Current treatment options are inefficient and result in drastic impairment of the general immunity. To selectively eliminate responsible alloreactive B cells characterized by anti-donor-HLA B cell receptors (BCRs), we generated T cells overcoming rejection by antibodies (CORA-Ts) engineered with a novel chimeric receptor comprising a truncated donor-HLA molecule as antigen recognition domain. As proof-of-concept, CORA receptors based on HLA-A∗02 were developed. In co-cultures with anti-HLA-A∗02 B cell lines, CORA-Ts were specifically activated, released pro-inflammatory mediators, and exhibited strong cytotoxicity resulting in an effective reduction of anti-HLA-A∗02 antibody release. Significant reduction of growth of an anti-HLA-A∗02 B cell line could be confirmed using an in vivo mouse model. Modification of the CORA receptor effectively abrogated T cell binding, thereby avoiding T cell sensitization. Additionally, using CRISPR-Cas9-mediated knockout of the FKBP12 gene, CORA-Ts were able to resist immunosuppressive treatment with tacrolimus, thereby allowing high efficiency in transplant patients. Our results demonstrate that CORA-Ts are able to specifically eliminate alloreactive, anti-HLA B cells, thus selectively preventing anti-HLA antibody release even under immunosuppressive conditions. This suggests CORA-Ts as potent approach to combat AMR and improve long-term graft survival in SOT patients while preserving their overall B cell immunity.

Advance in chimeric antigen receptor T therapy in autoimmune diseases

Autoimmune diseases are a group of diseases in which the body's immune system misrecognizes its own antigens resulting in an abnormal immune response, which can lead to pathological damage to or abnormal functioning of its own tissues. Current treatments are mainly hormones and broad-spectrum immunosuppressants, but these can lead to a decline in the patient's immunity. Chimeric antigen receptor T (CAR-T) Cell therapy has emerged, and now the structure of CAR has changed from first generation to fourth generation of CAR. The significant achievement of CAR-T therapy to B-cell leukemia has also inspired the treatment of autoimmune diseases, and by investigating the mechanisms of different autoimmune diseases, different designs of CAR-T can be used to specifically treat autoimmune diseases. In this review, we will discuss the therapeutic strategies of CAR-T cells in different autoimmune diseases and the limitations of the treatment.

A new therapeutic pathway in autoimmune diseases: chimeric antigen receptor T cells (CAR-T) targeting specific cell subtypes or antigen-specific B lymphocytes—a brief review

In hematological malignancies, autologous immunotherapy with T lymphocytes expressing a chimeric antigen receptor (CAR-T) has been successfully applied. CAR enhances the immuno-cellular effector system directly against cells expressing target antigens. The objective here was to discuss the prospects of applying CAR-T and its variants in autoimmune diseases (AIDs) to deplete pathogenic autoantibodies by eliminating B lymphocytes and plasma cells. B cells play a crucial role in the pathogenesis of AID through the production of autoantibodies, cytokine dysregulation, antigen presentation, and regulatory dysfunction. In AID with numerous autoreactive clones against various autoantigens, such as systemic lupus erythematosus, rheumatoid arthritis, vasculitis, myositis, and systemic sclerosis, CAR-T targeting CD19/CD20 and B-cell maturation antigen (BCMA) have shown success in preclinical and clinical studies, representing an innovative option for refractory patients when standard treatments fail. The suppression of B lymphocytes reactive against specific antigens using cytolytic T cells carrying a chimeric autoantibody receptor (CAAR-T) offers a promising approach for managing various AIDs, especially those with characterized pathogenic autoantibodies, such as pemphigus vulgaris, myasthenia gravis, and anti-NMDAR autoimmune encephalitis. CAAR-T allows the elimination of autoreactive B lymphocytes without compromising the general functionality of the immune system, minimizing common side effects in general immunosuppressive therapies, including immunobiologicals and CAR-T. In vitro, preclinical, and clinical (phase 1) studies have demonstrated the efficacy and specificity of CAR-T and CAAR-T in several AIDs; however, extensive clinical trials (phase 3) are required to assess their safety and clinical applicability. These advances promise to enhance precision medicine in the management of AIDs, offering personalized treatments for individual patients.

Emerging cell therapies in the vasculitis field

ANCA vasculitis is a systemic autoimmune small-vessel vasculitis characterized by autoantibodies targeting either MPO or PR3. While patients with ANCA vasculitis are successfully treated with broad-spectrum immunosuppression, these treatments often leave patients vulnerable to infections. Research in the field has made positive gains in regards to understanding autoantigen specificity and immune cell subset involvement in disease pathogenesis, relapse and remission. This review examines the state of the research field as it relates to possible new antigen- and cell-specific therapies in the vasculitis field. Potential avenues of therapeutic interest include selective elimination of autoreactive B cells by bispecific antibodies, tolerogenic liposomes or engineered T cells. Additionally, restoration of regulatory T-cell function is an attractive avenue to prolong remission of disease. Collectively, the field is well poised to begin investigating new and emerging cell therapies.

Chimeric antigen receptor-modified T-cell therapy: Recent updates and challenges in autoimmune diseases

Chimeric antigen receptor (CAR) T-cell therapy (CAR-T) has revolutionized the treatment of hematologic malignancies, demonstrating significant clinical efficacy and leading to US Food and Drug Administration approval of several CAR T-cell-based products. This success has prompted exploration of CAR-T in other disease areas, including autoimmune diseases (AIDs). CAR-T targeting B cells has been shown to provide clinical and biological improvements in patients with refractory AIDs. The aim of this review is to discuss promising strategies involving CAR-T in AIDs, such as those targeting B cells and T cells, and to explore new approaches targeting fibroblasts or plasmacytoid dendritic cells. Despite these advances, the application of CAR-T in AIDs faces several unique challenges. The quality and functionality of T cells in patients with AIDs may be compromised as a result of previous treatments and the underlying inflammatory state, affecting the generation and efficacy of CAR-T. In addition, achieving adequate tissue biodistribution and persistence of CAR T cells in affected tissues remains a major challenge. Finally, the high costs associated with T-cell production pose economic problems, particularly in the context of chronic diseases, which are far more numerous than the hematologic diseases for which CAR-Ts have been granted marketing authorization to date. If the indications for CAR-T increase significantly, production costs will have to drop drastically in order to obtain reliable economic models.

Barriers to CAR T-cell therapy in rheumatology

Chimeric antigen receptor (CAR) T cells have recently shown remarkable promise in treating rheumatic diseases, including systemic lupus erythematosus (SLE), idiopathic inflammatory myopathies, and systemic sclerosis. Currently, there are 37 clinical trials registered for CAR T-cell therapy in rheumatic diseases and many more are being planned. Much of this enthusiasm is justifiable, but widespread adoption of CAR T-cell therapy in rheumatology faces several barriers. The trajectory of autoimmune diseases differs from malignancies and a surprisingly narrow population could be eligible for CAR T-cell therapy. Current CAR T-cell approaches rely on B-cell depletion, which has a mixed record of success for many diseases. The high cost of CAR T-cell therapy and potential safety concerns, such as cytokine release syndrome and long-term infection risks, also pose substantial challenges. Moving forward, more targeted CAR T-cell approaches, such as antigen-specific chimeric autoantibody receptors or chimeric autoantigen T-cell receptors, could offer greater efficacy and safety in treating rheumatic diseases.

Composition and function of AChR chimeric autoantibody receptor T cells for antigen-specific B cell depletion in myasthenia gravis

In acetylcholine receptor (AChR)-seropositive myasthenia gravis (MG), anti-AChR autoantibodies impair neuromuscular transmission and cause severe muscle weakness. MG therapies broadly suppress immune function, risking infections. We designed a chimeric autoantibody receptor (CAAR) expressing the 210-amino acid extracellular domain of the AChR α subunit (A210) linked to CD137-CD3ζ cytoplasmic domains to direct T cell cytotoxicity against anti-AChRα B cells. A210-CAART incorporating a CD8α transmembrane domain (TMD8α) showed functional but unstable surface expression, partially restored by inhibiting lysosomal degradation. A210-CAART with a CD28 TMD showed sustained surface expression, independent of TMD dimerization motifs. In a mouse xenograft model, A210.TMD8α-CAART demonstrated early control of anti-AChR B cell outgrowth but subsequent rebound and loss of surface CAAR expression, whereas A210.TMD28-CAART induced sustained surface CAAR expression and target cell elimination. This study demonstrates the importance of the CD28 TMD for CAAR stability and in vivo function, laying the groundwork for future development of precision cellular immunotherapy for AChR-MG.

Dia-B-Ties: B Cells in the Islet-Immune-Cell Interface in T1D

Type 1 diabetes (T1D) is an autoimmune disease that affects an estimated 30 million people worldwide and results in a lifelong dependency of exogenous insulin treatments. While T1D is characterized by T-cell driven-destruction of the insulin-secreting β cells, B lymphocytes play a key role in the islet-immune interface. B cells are an essential intermediary between islet cells and other immune-cell populations. Through antigen presentation, cytokine secretion, and antibody production, B cells play a role in activating autoreactive islet-specific T cells, thus potentiating pancreatic inflammation in the early stages of T1D. Despite this, their role in disease development remains an understudied feature of T1D with significant therapeutic potential. Herein, we will discuss the current knowledge of the islet-immune-cell interface within T1D through the lens of B lymphocytes. We will also consider knowledge gaps that may be limiting further therapeutic opportunities.

Synthetic receptor-based cell therapies for autoimmune diseases: an update

Increasing frequency of autoimmune diseases is one of the major problems in modern societies. Despite the introduction of new therapeutic agents for autoimmunity over the past several decades, more progress is needed. Synthetic receptor-based cell therapies are being adopted as an option for treating autoimmune diseases from the field of oncology. Currently evaluated strategies can be summarized into two approaches. The first one is the elimination of autoreactive cells by targeting them, for example, with CAR-T or CAAR-T cells. The second is based on rebalancing the proinflammatory milieu with engineered immunosuppressive cells, for example, CAR-Treg. Both approaches can be supplemented with the use of synthetic systems such as Split-CAR, SynNotch, MESA, GEMS, and SNIPR, or prospective off-the-shelf approaches, for example, in situ use of the in vitro transcribed mRNA, ultimately allowing for enhanced efficacy and safety. The primary goal of our review is to provide some perspective on both strategies in basic, translational, and clinical studies with all their advantages and disadvantages to allow for informed future design of adoptive cell therapies for autoimmune diseases.

Is there a place for engineered immune cell therapies in autoimmune diseases?

The ability to engineer immune cells yielded a transformative era in oncology. Early clinical trials demonstrated the efficacy of chimeric antigen receptor (CAR) T cells in resetting the immune system, motivating the expansion of this treatment beyond cancer, including autoimmune conditions. In this review, we discuss the current state of CAR T cell research in autoimmune diseases, examining the main challenges that limit widespread adoption of this therapy, such as complex isolation protocols, stringent immunosuppression, risk of secondary malignancies, and variable efficacy. We also review the studies addressing these limitations by development of off-the-shelf allogeneic CAR T cells, tunable safety systems, and antigen-specific therapies, which hold the potential to improve safety and accessibility of this treatment in clinical practice.

Expanding the horizon of CAR T cell therapy: from cancer treatment to autoimmune diseases and beyond

Chimeric antigen receptor (CAR)-T-cell therapy has garnered significant attention for its transformative impact on the treatment of hematologic malignancies such as leukemia and lymphoma. Despite its remarkable success, challenges such as resistance, limited efficacy in solid tumors, and adverse side effects remain prominent. This review consolidates recent advancements in CAR-T-cell therapy and explores innovative engineering techniques and strategies to overcome the immunosuppressive tumor microenvironment (TME). We also discuss emerging applications beyond cancer, including autoimmune diseases and chronic infections. Future perspectives highlight the development of more potent CAR-T cells with increased specificity and persistence and reduced toxicity, providing a roadmap for next-generation immunotherapies.

Antigen-presenting fibroblasts: emerging players in immune modulation and therapeutic targets

Antigen-presenting fibroblasts are a newly recognized subset that challenges the traditional view of these cells as mere structural components. Under pathological or environmental stimuli, fibroblasts acquire antigen-presenting capabilities through the expression of MHC-II molecules and co-stimulatory factors, enabling them to interact with T cells and modulate immune responses. These specialized fibroblasts have been identified across various tissues and diseases, where they play context-dependent roles, either amplifying immune dysregulation or contributing to immune homeostasis. This review synthesizes recent advances in understanding the origins, activation, and functions of antigen-presenting fibroblasts. It highlights their role in promoting pathogenic immune responses and offering therapeutic opportunities through targeted modulation. Advancing our understanding of antigen-presenting fibroblasts holds great promise for developing innovative approaches to immune modulation and therapy across a range of diseases.

IL-36-driven pustulosis: Transcriptomic signatures match between generalized pustular psoriasis (GPP) and acute generalized exanthematous pustulosis (AGEP)

BACKGROUND

Due to similarities, the distinction between generalized pustular psoriasis (GPP) and acute generalized exanthematous pustulosis (AGEP) has been a matter of debate for a long time.

OBJECTIVES

Our aim was to define the molecular features of GPP and AGEP.

METHODS

We analyzed skin biopsy samples and clinical data from 125 patients with AGEP, GPP, palmoplantar pustulosis (PPP), plaque psoriasis (PSO), and nonpustular cutaneous adverse drug reactions (ADRs), as well as from healthy skin controls using RNA-sequencing and blinded histopathologic analyses.

RESULTS

The transcriptome and histopathologic features of AGEP and GPP samples exhibited significant overlap (177 differentially expressed genes [DEGs] in GPP and AGEP compared to healthy skin, only 2 DEGs comparing AGEP and GPP). Yet, they displayed marked differences from those of PPP, PSO, and ADR samples, with a notable number of DEGs (131 DEGs comparing AGEP and PSO, 75 DEGs comparing AGEP and PPP, and 52 DEGs comparing AGEP and ADR). A transcriptome profile subgroup evaluation of >13,000 analyzed genes did not reveal any DEGs in drug-induced GPP and AGEP. Moreover, the immune response pattern and immune cell composition did not differ between drug-induced GPP and AGEP, whereas non-drug-induced GPP had higher expression of TH17-cell-related genes and a higher neutrophil count than AGEP.

CONCLUSIONS

We propose that AGEP is a drug-induced variant of GPP and therefore part of IL-36-related pustulosis. A key signature overarching this spectrum was identified, thereby opening the therapeutic approach of IL-36 inhibition to all subtypes of the disease.

How to focus on autoantigen-specific lymphocytes: a review on diagnosis and treatment of Sjogren's syndrome

Sjogren's syndrome (SS) is an autoimmune epithelitis characterized by focal lymphocytic infiltration against self-antigens leading to progressive glandular dysfunction, which can develop to multisystem manifestation. The classification criteria for SS emphasizes glandular lymphocyte infiltrates and anti-SSA/SSB seropositivity, which is usually manifested in advanced patients. Therapeutically, apart from symptomatic treatment, treatment of SS is based on glucocorticoids and conventional synthetic disease-modifying antirheumatic drugs with global immunosuppression, but the efficacy of biologic or targeted synthetic therapies is still sparse. Currently, emerging studies focus on autoantigen-specific immunotherapies to treat autoimmune disorders by directly eliminating autoreactive cell subsets and inducing tolerance by increasing the autoreactive regulatory lymphocytes. Herein, we summarize the current state of research on the autoantigen-specific approaches for detecting autoreactive lymphocytes and outline the current autoantigen-specific immunotherapies in other autoimmune disorders and their attempts in treatment of SS. Last, we discuss the potential value of focusing on autoantigen-specific lymphocytes in the early diagnosis, monitoring, and targeted treatment of SS. Potential strategies for targeting autoreactive lymphocytes need to be confirmed in SS.

Advances in engineered T cell immunotherapy for autoimmune and other non-oncological diseases

Adoptive immunotherapy using engineered T cells expressing chimeric antigen receptors has shown remarkable success in treating patients with hematological malignancies. However, realizing broader therapeutic applications of engineered T cells in other diseases requires further exploration in clinical investigations. In this review, we highlight recent advances in the engineering of T cells in non-oncology areas, including autoimmune and inflammatory diseases, infections, fibrosis, hemophilia, and aging. Chimeric antigen receptor immunotherapy has shown good outcomes in non-oncology areas, but many challenges remain in improving its safety and efficacy and and expanding its application to the treatment of non-oncological diseases.

The B-cells paradigm in systemic sclerosis: an update on pathophysiology and B-cell-targeted therapies

Systemic sclerosis (SSc) is considered a rare autoimmune disease in which there are alterations of both the innate and adaptive immune response resulting in the production of autoantibodies. Abnormalities of the immune system compromise the normal function of blood vessels leading to a vasculopathy manifested by Raynaud's phenomenon, an early sign of SSc . As a consequence of this reactive picture, the disease can evolve leading to tissue fibrosis. Several SSc-specific autoantibodies are currently known and are associated with specific clinical manifestations and prognosis. Although the pathogenetic role of these autoantibodies is still unclear, their production by B cells and plasma cells suggests the importance of these cells in the development of SSc. This review narratively examines B-cell dysfunctions and their role in the pathogenesis of SSc and discusses B-cell-targeted therapies currently used or potentially useful for the management of end-organ complications.

Current advancements in cellular immunotherapy for autoimmune disease

The management of autoimmune diseases is currently limited by therapies that largely suppress the immune system, often resulting in partial and temporary remissions. Cellular immunotherapies offer a targeted approach by redirecting immune cells to correct the underlying autoimmunity. This review explores the latest advances in cellular immunotherapies for autoimmune diseases, focusing on various strategies, such as the use of chimeric antigen receptor (CAR) T cells, chimeric auto-antibody receptor (CAAR) T cells, regulatory T cells (Tregs), and tolerogenic dendritic cells (TolDCs). We review recent preclinical studies and results from clinical trials that demonstrate the potential for these therapies to either deplete autoreactive cells or promote immune tolerance through broad or selective targeting of immune cell populations. Key challenges such as ensuring specificity, preventing off-target effects, and improving the longevity of therapeutic effects are discussed. The evolving landscape of cellular immunotherapies holds promise for more durable treatment responses and increased specificity for autoimmune disease treatment.

CAR-T cell therapy: developments, challenges and expanded applications from cancer to autoimmunity

Chimeric Antigen Receptor (CAR)-T cell therapy has rapidly emerged as a groundbreaking approach in cancer treatment, particularly for hematologic malignancies. However, the application of CAR-T cell therapy in solid tumors remains challenging. This review summarized the development of CAR-T technologies, emphasized the challenges and solutions in CAR-T cell therapy for solid tumors. Also, key innovations were discussed including specialized CAR-T, combination therapies and the novel use of CAR-Treg, CAR-NK and CAR-M cells. Besides, CAR-based cell therapy have extended its reach beyond oncology to autoimmune disorders. We reviewed preclinical experiments and clinical trials involving CAR-T, Car-Treg and CAAR-T cell therapies in various autoimmune diseases. By highlighting these cutting-edge developments, this review underscores the transformative potential of CAR technologies in clinical practice.

Advances in chimeric antigen receptor T cell therapy for autoimmune and autoinflammatory diseases and their complications

Chimeric antigen receptor T (CAR-T) cells are genetically engineered T cells expressing transmembrane chimeric antigen receptors with specific targeting abilities. As an emerging immunotherapy, the use of CAR-T cells has made significant breakthroughs in cancer treatment, particularly for hematological malignancies. The success of CAR-T cell therapy in blood cancers highlights its potential for other conditions in which the clearance of pathological cells is therapeutic, such as liver diseases, infectious diseases, heart failure, and diabetes. Given the limitations of current therapies for autoimmune diseases, researchers have actively explored the potential therapeutic value of CAR-T cells and their derivatives in the field of autoimmune diseases. This review focuses on the research progress and current challenges of CAR-T cells in autoimmune diseases with the aim of providing a theoretical basis for the precise treatment of autoimmune diseases. In the future, CAR-T cells may present new therapeutic modalities and ultimately provide hope for patients with autoimmune diseases.

Selected Aspects of the Neuroimmunology of Cell Therapies for Neurologic Disease: Perspective

Neurologic disease remains a cause of incalculable suffering, a formidable public health burden, and a wilderness of complex biology and medicine. At the same time, advances in basic science, technology, and the clinical development toolkit bring meaningful benefit for patients along with realistic hope for those whose conditions remain inadequately treated. This perspective focuses on cell-based therapies for neurologic disease, with particular emphasis on neuroimmunologic disorders and on the immunologic considerations of cell therapy for nonimmune conditions. I will consider the use of chimeric antigen receptor (CAR)-T effector cells and regulatory T-cell therapies for autoimmune conditions. I will briefly discuss the immune aspects of pluripotent stem cell (PSC)-derived neuronal therapies. With apologies for the omission, we do not discuss mesenchymal stem cells, glial progenitor cells, or CAR-NK cells, primarily for space limitations.

CAR T-Cell Therapy for Rheumatic Diseases: What Does the Future Hold?

Chimeric antigen receptor (CAR) T-cell therapy, initially successful in treating hematological malignancies, is emerging as a potential treatment for autoimmune diseases, including rheumatic conditions. CAR T cells, engineered to target and eliminate autoreactive B cells, offer a novel approach to managing diseases like systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and inflammatory myopathies, where B cells play a pivotal role in disease pathology. Early case reports have demonstrated promising results, with patients achieving significant disease remission, normalization of serological markers, and the ability to discontinue traditional immunosuppressive therapies, which supported the initiation of several clinical trials. However, the application of CAR T-cell therapy in chronic inflammatory rheumatic disorders poses unique challenges, including patient heterogeneity, the risk of adverse effects such as cytokine release syndrome, and the high costs associated with the therapy. Despite these challenges, the potential for CAR T cells to provide long-term remission or even a cure in refractory autoimmune diseases is significant. Ongoing research aims to optimize CAR T-cell constructs and improve safety profiles, paving the way for broader application in rheumatic diseases. If these challenges can be addressed, CAR T-cell therapy could revolutionize the treatment landscape for chronic inflammatory rheumatic disorders, offering new hope for patients with severe, treatment-resistant conditions.

Cars pick up another passenger: Organ transplantation

With over 30,000 patients having received CAR T cells as a treatment for malignancy, our experience in oncology has facilitated numerous efforts to adapt the CAR therapeutic platform for diseases and conditions beyond cancer. Recognition of their efficacy, where traditional small molecule or biologic therapies fail, has spurred multiple efforts leveraging CAR T cells for immune modulation in the setting of organ/tissue transplantation. In the present review, we discuss CAR T cell approaches that are currently under development, to target both humoral and cellular alloimmunity. These include CAR T platforms repurposed from oncology and autoimmune diseases, as well as ones designed specifically to target alloimmunity in transplant. We also present important challenges and application considerations that will need to be addressed before we can expect successful clinical translation. Finally, we highlight a few of the exciting advances currently in development that are likely to pave a smoother path to translating CAR T cell therapies into transplant patients.

Innovative cell therapies for systemic sclerosis: available evidence and new perspectives

INTRODUCTION

Systemic sclerosis (SSc) is the rheumatic disease with the highest individual mortality rate with a detrimental impact on quality of life. Cell-based therapies may offer new perspectives for this disease as recent phase I trials support the safety of IV infusion of allogeneic mesenchymal stromal cells in SSc and case reports highlight the potential use of Chimeric Antigen Receptor (CAR)-T cells targeting CD19 in active SSc patients who have not responded to conventional immunosuppressive therapies.

AREAS COVERED

This narrative review highlights the most recent evidence supporting the use of cellular therapies in SSc as well as their potential mechanisms of action and discusses future perspectives for cell-based therapies in SSc. Medline/PubMed was used to identify the articles of interest, using the keywords 'Cellular therapies,' 'Mesenchymal stromal cells,' 'Chimeric Antigen Receptor' AND 'systemic sclerosis.' Milestones articles reported by the authors were also used.

EXPERT OPINION

Cellular therapies may represent an opportunity for long-term remission/cure in patients with different autoimmune diseases, including SSc who have not responded to conventional therapies. Multiple ongoing phase I/II trials will provide greater insights into the efficacy and toxicity of cellular therapies.

Development of Peptide Mimics of the Human Acetylcholine Receptor Main Immunogenic Region for Treating Myasthenia Gravis

We have designed and produced 39 amino acid peptide mimics of the Torpedo and human acetylcholine receptors' (AChRs) main immunogenic regions (MIRs). These conformationally sensitive regions consist of three non-contiguous segments of the AChR α-subunits and are the target of 50-70% of the anti-AChR autoantibodies (Abs) in human myasthenic serum and in the serum of rats with a model of that disease, experimental autoimmune myasthenia gravis (EAMG), induced by immunizing the rats with the Torpedo electric organ AChR. These MIR segments covalently joined together bind a significant fraction of the monoclonal antibodies (mAbs) raised in rats against electric organ AChR. Many of these mAbs cross react with the rat neuromuscular AChR MIR and induce myasthenic symptoms when injected into naïve rats. The human MIR mimic peptide (H39MIR) is evolutionarily related to that of the Torpedo electric organ MIR mimic peptide (T39MIR) with eight amino acid differences between the two MIR mimics. The mAbs raised to the electric organ AChR MIR cross react with the human and scores of other species' neuromuscular AChRs. However, the mAbs do not cross react with the H39MIR mimic attached to the N-terminus of an intein-chitin-binding domain (H39MIR-IChBD) even though they do bind to the T39MIR-IChBD construct. To account for this difference in binding anti-MIR mAbs, each of the eight human amino acids was substituted individually into the T39MIR-IChBD, and four of them were found to weaken mAb recognition. Substituting the corresponding four Torpedo amino acids individually and in combination into the homologous positions in H39MIR-IChBD makes chimeric human MIR mimic peptides (T/H39MIR), some of which bind anti-MIR mAbs and anti-MIR Abs from rat EAMG and human MG sera. The best mAb binding chimeric peptide constructs may potentially serve as the basis of a diagnostic anti-MIR Ab titer assay that is both prognostic and predictive of disease severity. Furthermore, the best peptides may also serve as the targeting element of a non-steroidal antigen-specific treatment of MG to remove anti-AChR MIR Abs, either as fused to the N-terminals of the human immunoglobin Fc fragment or as the targeting component of a T cell chimeric autoantibody receptor (CAAR) directed to anti-MIR memory B cells for elimination.

Chimeric HLA antibody receptor T cell therapy for humoral transplant rejection

Antibody-mediated rejection (ABMR) is a significant obstacle to achieving optimal long-term outcomes after solid organ transplantation. The presence of donor-specific antibodies (DSAs), particularly against human leucocyte antigen (HLA), increases the risk of allograft rejection and subsequent graft loss. No effective treatment for ABMR currently exists, warranting novel approaches to target the HLA-specific humoral alloimmune response. Cellular therapies may hold promise to this end. According to publicly available sources as of now, three independent laboratories have genetically engineered a chimeric HLA antibody receptor (CHAR) and transduced it into human T cells, based on the demonstrated efficacy of chimeric antigen receptor T cell therapies in malignancies. These CHAR-T cells are designed to exclusively eliminate B cells that produce donor-specific HLA antibodies, which form the cornerstone of ABMR. CHAR technology generates potent and functional human cytotoxic T cells to target alloreactive HLA-specific B cells, sparing B cells with other specificities. Thus CHAR technology may be used as a selective desensitization protocol and to treat ABMR after solid organ transplantation.

CAR T-cell therapy for systemic lupus erythematosus: current status and future perspectives

Systemic lupus erythematosus (SLE) and lupus nephritis (LN) are debilitating autoimmune disorders characterized by pathological autoantibodies production and immune dysfunction, causing chronic inflammation and multi-organ damage. Despite current treatments with antimalarial drugs, glucocorticoids, immunosuppressants, and monoclonal antibodies, a definitive cure remains elusive, highlighting an urgent need for novel therapeutic strategies. Recent studies indicate that chimeric antigen receptor T-cell (CAR-T) therapy has shown promising results in treating B-cell malignancies and may offer a significant breakthrough for non-malignant conditions like SLE. In this paper, we aim to provide an in-depth analysis of the advancements in CAR-T therapy for SLE, focusing on its potential to revolutionize treatment for this complex disease. We explore the fundamental mechanisms of CAR-T cell action, the rationale for its application in SLE, and the immunological underpinnings of the disease. We also summarize clinical data on the safety and efficacy of anti-CD19 and anti-B cell maturation antigen (BCMA) CAR-T cells in targeting B-cells in SLE. We discuss the clinical implications of these findings and the potential for CAR-T therapy to improve outcomes in severe or refractory SLE cases. The integration of CAR-T therapy into the SLE treatment paradigm presents a new horizon in autoimmunity research and clinical practice. This review underscores the need for continued exploration and optimization of CAR-T strategies to address the unmet needs of SLE patients.

CAR-based cell therapies for systemic lupus erythematosus

ABSTRACT

The remarkable efficacy of chimeric antigen receptor (CAR) T cell therapy in hematological malignancies has provided a solid basis for the therapeutic concept, wherein specific pathogenic cell populations can be eradicated by means of targeted recognition. During the past few years, CAR-based cell therapies have been extensively investigated in preclinical and clinical research across various non-tumor diseases, with particular emphasis in the treatment of autoimmune diseases (ADs), yielding significant advancements. The recent deployment of CD19-directed CAR T cells has induced long-lasting, drug-free remission in patients with systemic lupus erythematosus (SLE) and other systemic AD, alongside a more profound immune reconstruction of B cell repertoire compared with conventional immunosuppressive agents and B cell-targeting biologics. Despite the initial success achieved by CAR T cell therapy, it is critical to acknowledge the divergences in its application between cancer and AD. Through examining recent clinical studies and ongoing research, we highlight the transformative potential of this therapeutic approach in the treatment of SLE, while also addressing the challenges and future directions necessary to enhance the long-term efficacy and safety of CAR-based cell therapies in clinical practice.