Evolving understanding of autoimmune mechanisms and new therapeutic strategies of autoimmune disorders.

Autoimmune disorders are characterized by aberrant T cell and B cell reactivity to the body's own components, resulting in tissue destruction and organ dysfunction. Autoimmune diseases affect a wide range of people in many parts of the world and have become one of the major concerns in public health. In recent years, there have been substantial progress in our understanding of the epidemiology, risk factors, pathogenesis and mechanisms of autoimmune diseases. Current approved therapeutic interventions for autoimmune diseases are mainly non-specific immunomodulators and may cause broad immunosuppression that leads to serious adverse effects. To overcome the limitations of immunosuppressive drugs in treating autoimmune diseases, precise and target-specific strategies are urgently needed. To date, significant advances have been made in our understanding of the mechanisms of immune tolerance, offering a new avenue for developing antigen-specific immunotherapies for autoimmune diseases. These antigen-specific approaches have shown great potential in various preclinical animal models and recently been evaluated in clinical trials. This review describes the common epidemiology, clinical manifestation and mechanisms of autoimmune diseases, with a focus on typical autoimmune diseases including multiple sclerosis, type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, and sjögren's syndrome. We discuss the current therapeutics developed in this field, highlight the recent advances in the use of nanomaterials and mRNA vaccine techniques to induce antigen-specific immune tolerance.

Application of novel CAR technologies to improve treatment of autoimmune disease.

Chimeric antigen receptor (CAR) T cell therapy has become an important treatment for hematological cancers, and its success has spurred research into CAR T cell therapies for other diseases, including solid tumor cancers and autoimmune diseases. Notably, the development of CAR-based treatments for autoimmune diseases has shown great progress recently. Clinical trials for anti-CD19 and anti-BCMA CAR T cells in treating severe B cell-mediated autoimmune diseases, like systemic lupus erythematosus (SLE), have shown lasting remission thus far. CAR T cells targeting autoreactive T cells are beginning clinical trials for treating T cell mediated autoimmune diseases. Chimeric autoantigen receptor (CAAR) T cells specifically target and eliminate only autoreactive B cells, and they have shown promise in treating mucosal pemphigus vulgaris and MuSK myasthenia gravis. Regulatory CAR T cells have also been developed, which show potential in altering autoimmune affected areas by creating a protective barrier as well as helping decrease inflammation. These new treatments are only the beginning of potential CAR T cell applications in treating autoimmune disease. Novel CAR technologies have been developed that increase the safety, potency, specificity, and efficacy of CAR T cell therapy. Applying these novel modifications to autoimmune CARs has the potential to enhance the efficacy and applicability of CAR therapies to autoimmune disease. This review will detail several recently developed CAR technologies and discuss how their application to autoimmune disease will improve this emerging field. These include logic-gated CARs, soluble protein-secreting CARs, and modular CARs that enable CAR T cell therapies to be more specific, reach a wider span of target cells, be safer for patients, and give a more potent cytotoxic response. Applying these novel CAR technologies to the treatment of autoimmune diseases has the potential to revolutionize this growing application of CAR T cell therapies.

Cutting-edge approaches to B-cell depletion in autoimmune diseases.

B-cell depletion therapy (BCDT) has been employed to treat autoimmune disease for ~20 years. Immunoglobulin G1 (IgG1) monoclonal antibodies targeting CD20 and utilizing effector function (eg, antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity, antibody-dependent cellular phagocytosis) to eliminate B cells have historically been the predominant therapeutic approaches. More recently, diverse BCDT approaches targeting a variety of B-cell surface antigens have been developed for use in hematologic malignancies, including effector-function-enhanced monoclonal antibodies, chimeric antigen receptor T-cell (CAR-T) treatment, and bispecific T-cell engagers (TCEs). The latter category of antibodies employs CD3 engagement to augment the killing of target cells. Given the improvement in B-cell depletion observed with CAR-T and TCEs compared with conventional monospecific antibodies for treatment of hematologic malignancies and the recent case reports demonstrating therapeutic benefit of CAR-T in autoimmune disease, there is potential for these mechanisms to be effective for B-cell-mediated autoimmune disease. In this review, we discuss the various BCDTs that are being developed in autoimmune diseases, describing the molecule designs, depletion mechanisms, and potential advantages and disadvantages of each approach as they pertain to safety, efficacy, and patient experience. Additionally, recent advances and strategies with TCEs are presented to help broaden understanding of the potential for bispecific antibodies to safely and effectively engage T cells for deep B-cell depletion in autoimmune diseases.

LC3-associated phagocytosis and human diseases: Insights from mechanisms to therapeutic potential.

LC3-associated phagocytosis (LAP) is a distinct type of autophagy that involves the sequestration of extracellular material by phagocytes. Beyond the removal of dead cells and cellular debris from eukaryotic cells, LAP is also involved in the removal of a variety of pathogens, including bacteria, fungi, and viruses. These events are integral to multiple physiological and pathological processes, such as host defense, inflammation, and tissue homeostasis. Dysregulation of LAP has been associated with the pathogenesis of several human diseases, including infectious diseases, autoimmune diseases, and neurodegenerative diseases. Thus, understanding the molecular mechanisms underlying LAP and its involvement in human diseases may provide new insights into the development of novel therapeutic strategies for these conditions. In this review, we summarize and highlight the current consensus on the role of LAP and its biological functions in disease progression to propose new therapeutic strategies. Further studies are needed to illustrate the precise role of LAP in human disease and to determine new therapeutic targets for LAP-associated pathologies.

CAR immunotherapy in autoimmune diseases: promises and challenges.

In recent years, the use of chimeric antigen receptor (CAR)-T cells has emerged as a promising immunotherapy in multiple diseases. CAR-T cells are T cells genetically modified to express a surface receptor, known as CAR, for the targeting of cognate antigens on specific cells. The effectiveness of CAR-T cell therapy in hematologic malignancies including leukemia, myeloma, and non-Hodgkin's lymphoma has led to consider its use as a potential avenue of treatment for autoimmune diseases. However, broadening the use of CAR-T cell therapy to a large spectrum of autoimmune conditions is challenging particularly because of the possible development of side effects including cytokine release syndrome and neurotoxicity. The design of CAR therapy that include additional immune cells such as double-negative T cells, γδ T cells, T regulatory cells and natural killer cells has shown promising results in preclinical studies and clinical trials in oncology, suggesting a similar potential utility in the treatment of autoimmune diseases. This review examines the mechanisms, efficacy, and safety of CAR approaches with a focus on their use in autoimmune diseases including systemic lupus erythematosus, Sjögren's syndrome, systemic sclerosis, multiple sclerosis, myasthenia gravis, lupus nephritis and other autoimmune diseases. Advantages and disadvantages as compared to CAR-T cell therapy will also be discussed.

PIM1 signaling in immunoinflammatory diseases: an emerging therapeutic target.

PIM1, the proviral integration site for Moloney murine leukemia virus, is a member of the serine/threonine protein kinase family. It is involved in many biological events, such as cell survival, cell cycle progression, cell proliferation, and cell migration, and has been widely studied in malignant diseases. However, recent studies have shown that PIM1 plays a prominent role in immunoinflammatory diseases, including autoimmune uveitis, inflammatory bowel disease, asthma, and rheumatoid arthritis. PIM1 can function in inflammatory signal transduction by phosphorylating multiple inflammatory protein substrates and mediating macrophage activation and T lymphocyte cell specification, thus participating in the development of multiple immunoinflammatory diseases. Moreover, the inhibition of PIM1 has been demonstrated to ameliorate certain immunoinflammatory disorders. Based on these studies, we suggest PIM1 as a potential therapeutic target for immunoinflammatory diseases and a valid candidate for future research. Herein, for the first time, we provide a detailed review that focuses on the roles of PIM1 in the pathogenesis of immunoinflammatory diseases.

Off-the-shelf CAR-T cells could prove paradigm shifting for autoimmune diseases.

Early reports suggest that chimeric antigen receptor (CAR)-T therapy has remarkable potential for treating autoimmune disease. Current approaches rely on autologous CAR-T cells, creating a bottleneck to the broad deployment of this therapy. In this issue of Cell, Wang et al.1 report the first use of allogeneic CAR-T cells in three patients with systemic autoimmune disease.

Fulminant Myocarditis in Patients With Autoimmune Disease That Requires Extracorporeal Membrane Oxygenation Support.

Myocarditis is a potentially life-threatening inflammatory disease of the myocardium, often resulting from infectious and immune-mediated responses. Clinical presentation in severe cases often results in a devastating illness requiring extracorporeal membrane oxygenation support as a result of cardiogenic shock. Although endomyocardial biopsy is still considered the gold standard for diagnosis, it often reveals nonspecific lymphocytic infiltration. Because the precise cause is usually unknown, the initial treatment typically involves immunosuppression and frequent assessment of myocardial contractility. This report presents 3 rare cases of autoimmune diseases (polymyositis, immunoglobulin G4-related disease, and systemic lupus erythematosus) that require extracorporeal membrane oxygenation support as a result of fulminant myocarditis, including their follow-up periods.

Regulatory T cells: masterminds of immune equilibrium and future therapeutic innovations.

Regulatory T cells (Tregs), a subset of CD4+T cells marked by the expression of the transcription factor forkhead box protein 3 (Foxp3), are pivotal in maintaining immune equilibrium and preventing autoimmunity. In our review, we addressed the functional distinctions between Foxp3+Tregs and other T cells, highlighting their roles in autoimmune diseases and cancer. We uncovered the dual nature of Tregs: they prevented autoimmune diseases by maintaining self-tolerance while contributing to tumor evasion by suppressing anti-tumor immunity. This study underscored the potential for targeted therapeutic strategies, such as enhancing Treg activity to restore balance in autoimmune diseases or depleting Foxp3+Tregs to augment anti-tumor immune responses in cancer. These insights laid the groundwork for future research and clinical applications, emphasizing the critical role of Foxp3+Tregs in immune regulation and the advancement of next-generation immunotherapies.

Current progress in CRISPR-Cas systems for autoimmune diseases.

A body develops an autoimmune illness when its immune system mistakenly targets healthy cells and organs. Eight million people are affected by more than 80 autoimmune diseases. The public's and individuals' well-being is put at risk. Type 1 diabetes, lupus, rheumatoid arthritis, and multiple sclerosisare autoimmune diseases. Tissue injury, nociceptive responses, and persistent inflammation are the results of these stresses. Concerns about healthcare costs, health, and physical limitations contribute to these issues. Given their prevalence, it is crucial to enhance our knowledge, conduct thorough research, and provide all-encompassing support to women dealing with autoimmune diseases. This will lead to better public health and better patient outcomes. Most bacteria's immune systems employ CRISPR-Cas, a state-of-the-art technique for editing genes. For Cas to break DNA with pinpoint accuracy, a guide RNA employs a predetermined enzymatic pathway. Genetic modifications started. After it was developed, this method was subjected to much research on autoimmune diseases. By modifying immune pathways, CRISPR gene editing can alleviate symptoms, promote immune system tolerance, and decrease autoimmune reactivity. The autoimmune diseases that CRISPR-Cas9 targets now have no treatment or cure. Results from early clinical trials and preclinical studies of autoimmune medicines engineered using CRISPR showed promise. Modern treatments for rheumatoid arthritis,multiple sclerosis, and type 1 diabetes aim to alter specific genetic or immune mechanisms. Accurate CRISPR editing can fix autoimmune genetic disorders. Modifying effector cells with CRISPR can decrease autoimmune reactions. These cells include cytotoxic T and B lymphocytes. Because of improvements in delivery techniques and kits, CRISPR medications are now safer, more effective, and more accurately targeted. It all comes down to intricate immunological reactions and unexpected side consequences. Revolutionary cures for autoimmune problems and highly personalized medical therapies have been made possible by recent advancements in CRISPR.

Microglial-mediated immune mechanisms in autoimmune uveitis: Elucidating pathogenic pathways and targeted therapeutics.

This review offers a comprehensive examination of the role of microglia in the pathogenesis of autoimmune uveitis, an inflammatory eye disease with significant potential for vision impairment. Central to our discussion is the dual nature of microglial cells, which act as both protectors and potential perpetrators in the immune surveillance of the retina. We explore the mechanisms of microglial activation, highlighting the key signaling pathways involved, such as NF-κB, JAK/STAT, MAPK, and PI3K/Akt. The review also delves into the genetic and environmental factors influencing microglial behavior, underscoring their complex interaction in disease manifestation. Advanced imaging techniques and emerging biomarkers for microglial activation, pivotal in diagnosing and monitoring the disease, are critically assessed. Additionally, we discuss current and novel therapeutic strategies targeting microglial activity, emphasizing the shift towards more precise and personalized interventions. This article aims to provide a nuanced understanding of microglial dynamics in autoimmune uveitis, offering insights into potential avenues for effective treatment and management.

Contribution of gut-derived T cells to extraintestinal autoimmune diseases.

The mammalian intestine harbors abundant T cells with high motility, where these cells can affect both intestinal and extraintestinal disorders. Growing evidence shows that gut-derived T cells migrate to extraintestinal organs, contributing to the pathogenesis of certain autoimmune diseases, including type 1 diabetes (T1D) and multiple sclerosis (MS). However, three key questions require further elucidation. First, how do intestinal T cells egress from the intestine? Second, how do gut-derived T cells enter organs outside the gut? Third, what is the pathogenicity of gut-derived T cells and their correlation with the gut microenvironment? In this Opinion, we propose answers to these questions. Understanding the migration and functional regulation of gut-derived T cells might inform precise targeting for achieving safe and effective approaches to treat certain extraintestinal autoimmune diseases.

Reflecting on a decade of the international consensus on ANA patterns (ICAP): Accomplishments and challenges from the perspective of the 7th ICAP workshop.

The International Consensus on ANA Patterns (ICAP) is an ongoing international initiative dedicated to harmonizing technical and interpretation aspects of the HEp-2 IFA test. Comprised of internationally recognized experts in autoimmunity and HEp-2 IFA testing, ICAP has operated for the last 10 years by promoting accurate reading, interpretation, and reporting of HEp-2 IFA images by professionals involved in various areas related to autoimmune diseases, such as clinical diagnostic laboratories, academic research, IVD industry, and patient care. ICAP operates through continuous information exchange with the international community and encourages the participation of younger experts from all over the world. The 7th ICAP workshop has addressed several aspects that originated from this interaction with the international community and has effectively established objective goals and tasks to be delivered over the next two years. Some of these are outlined in this article, including the planning of three audio-visual educational modules to be posted at the www.anapattern.org website, the classification of two novel HEp-2 IFA patterns, the implementation of a project dedicated to continuously updating the information on the clinical and immunologic relevance of the HEp-2 IFA patterns, and the launch of two additional branches of the HEp-2 Clinical and Immunological (HEp-2 CIC) project.

Frontiers in CAR-T cell therapy for autoimmune diseases.

Chimeric antigen receptor (CAR)-engineered T (CAR-T) cell therapy has demonstrated significant success in treating cancers. The potential of CAR-T cells is now being explored in the context of autoimmune diseases. Recent clinical trials have shown sustained and profound elimination of autoreactive B cells by CAR-T cells, leading to promising autoimmune disease control with minimal safety concerns. These encouraging results have inspired further investigation into CAR-T cell applications for a broader range of autoimmune diseases and the development of advanced cell products with improved efficacy and safety. In this review, we discuss the mechanisms by which CAR-T cells target autoimmune conditions, summarize current preclinical models, and highlight ongoing clinical trials, including CAR-T therapy design, clinical outcomes, and challenges. Additionally, we discuss the limitations and future directions of CAR-T therapy in the treatment of autoimmune diseases.

HSCT for systemic autoimmune diseases with neurologic involvement.

Over the past 25 years, hematopoietic stem cell transplantation (HSCT) has been evolving as specific treatment for patients with severe and refractory systemic autoimmune diseases, where mechanistic studies have provided evidence for a profound immune renewal facilitating the observed beneficial responses. In addition to autoimmune neurologic diseases, such as multiple sclerosis (MS) or neuromyelitis optica (NMO), rheumatic diseases with central or peripheral nervous system involvement and insufficient response to conventional immunosuppressive or biologic therapies represent a growing indication for autologous HSCT. They most commonly include connective tissue diseases, such as systemic lupus erythematosus (SLE), vasculitides, or rarer diseases from the autoinflammatory spectrum, such as Behçet's disease, where neurologic manifestations may represent the greatest disease burden. Neurologic manifestations may resemble those of MS, including myelitis optic neuropathy, stroke, or seizures. Outcomes of such manifestations are variable after autologous HSCT but most frequently improve or even resolve with the underlying disease, especially in SLE. This article will provide the current evidence and summarize the outcomes of HSCT for rheumatic autoimmune diseases with neurologic manifestations.

The EBMT-ADWP and the CIBMTR.

Hematopoietic stem cell transplantation (HSCT) has evolved over the last 25 years as a specific treatment of patients with severe neurologic autoimmune diseases (ADs), through eradication of the pathologic, immunologic memory, and profound immune "resetting." HSCT for ADs is recently facing a unique developmental phase across transplant centers. Data from patients undergoing HSCT and cellular therapies have been captured through the established major transplant registries, such as the European Society for Blood and Marrow Transplantation (EBMT) and the Center for International Blood and Marrow Transplant Research (CIBMTR). The EBMT Autoimmune Diseases Working Party (ADWP) is central to bringing together HSCT and disease-specialist communities. The AD section of the EBMT registry is the largest database of its kind worldwide, reporting more than 3700 transplants. Multiple sclerosis (MS) covers approximately 50% of transplants in AD, HSCT being an integral and standard-of-care part of the treatment algorithm. In the Americas, at least a subset of HSCT is reported to the CIBMTR, as reporting is voluntary. A total of 1400 recipients of autologous HSCT were reported and 1030 were performed for the treatment of neurologic conditions. MS accounts for 96% of all diagnoses among neurologic indications for HSCT. Although the activity of HSCT for MS is low in the United States in relation to its prevalence, the number of transplants has increased in recent years. In contrast, Mexico has reported a sharp increase in the number of these transplants. This chapter provides an overview of the EBMT and CIBMTR registries, then offers the current status and publication outputs in relation to neurologic AD.

The preclinical data and immunologic rationale for hematopoietic stem cell transplantation in autoimmunity.

The development of autoimmune diseases (ADs) is thought to be caused by a dysfunction of the intrinsic ability of our immune system for "self-nonself" discrimination. Following the breakdown of "self-tolerance," an orchestrated immune cascade develops, involving B- and T-lymphocytes and autoantibodies that target self-antigens. An imbalance of the regulatory immune network and a suitable genetic background, along with external (infectious and environmental) triggers, are all important contributors to the outbreak of clinical autoimmunity. Immunotherapies for ADs can be classified into treatments that are given continuously (chronic treatments) and therapies that are applied only once or intermittently, aiming to induce partial or complete reconstitution of the immune system [immune reconstitution therapies (IRTs)]. The principle underlying IRTs is based on the depletion of mature immune cells and the rebuilding of the immune system. During this process of immune reconstitution, a substantial change in the lymphocyte repertoire occurs, which may explain the impressive and long-term beneficial effects of IRTs, including the possibility of induction of tolerance to self-antigens. Hematopoietic (or bone marrow) stem cell transplantation (HSCT or BMT) represents the prototype-and the most radical type-of IRT therapy. The rationale for HSCT or BMT for the treatment of severe ADs is based on convincing proof in preclinical studies, utilizing various animal models of autoimmunity. More than 30 years' worth of pioneering experiments in various models of ADs have shown that HSCT can lead to substantial improvement or even cure of the autoimmune syndromes and induction of long-term tolerance to autoantigens. The success of treatment depends on how completely the autoantigen-reactive lymphocytes and memory cells are eradicated by the conditioning chemotherapy, which is administered in a single dose before the transplantation. The most successful conditioning methods in animal models of ADs are total body irradiation (TBI) and high-dose cyclophosphamide (CY). These preclinical studies, summarized in this review, have provided important data about the therapeutic potential of HSCT in human ADs and the associated mechanisms of action and have contributed to the formulation of guidelines for clinical applications of autologous or allogeneic HSCT/BMT in refractory autoimmunity.

The role of chemotherapy in hematopoietic stem cell transplantation for autoimmune disorders: From lymphoablative to myeloablative conditioning protocols.

Hematopoietic stem cell transplantation (HSCT) is a medical procedure used mainly for the treatment of onco-hematologic disorders. Over the last two decades, autologous HSCT has been explored for the treatment of neurologic autoimmune diseases (ADs), being multiple sclerosis (MS) the most frequent indication in this setting. HSCT is characterized by the sequential administration of a conditioning regimen (CR) and the infusion of hematopoietic stem cells (HSCs), previously collected either by the individual himself in the autologous transplant (AHSCT), or by a healthy donor in allogeneic HSCT. CR consists of the administration of high-dose chemotherapy and/or total body irradiation (TBI), that in ADs is usually associated with an immunodepleting serotherapy, either by an animal-derived polyclonal serum or a monoclonal antibody (MoAb), to induce intense immunosuppression. CRs are classified according to the European Society for Blood and Marrow Transplantation (EBMT) guidelines for HSCT in ADs in three grades of intensity according to the degrees of depletion of the hemato-lymphopoietic system induced. In the present chapter, after a brief overview of mobilization and CR adopted in the neurologic autoimmune setting, the role of chemotherapy in HSCT will be discussed, providing a historical perspective on the use of different regimens and summarizing the available evidence on potential associations between CR and outcomes.