Clinical and Experimental Neuroimmunology最新文献

Idiopathic inflammatory myopathies (IIMs), or myositis, are a heterogeneous group of autoimmune diseases affecting skeletal muscle and other organs. Recent research has revealed the important role of interferons (IFNs) in the pathogenesis of IIMs. This review summarizes the three types of IFNs and their functions in the immune system, focusing on their association with different IIM subtypes. Dermatomyositis (DM) is strongly associated with Type I IFNs. In contrast, inclusion body myositis (IBM), polymyositis with mitochondrial pathology (PM-mito), and anti-synthetase syndrome (ASyS) are predominantly associated with Type II IFN. This review explores the molecular mechanisms underlying these associations and their impact on muscle function. In addition, the potential of the IFN signaling pathway as a therapeutic target for IIMs will be discussed. Several clinical trials are currently underway or planned that target the IFN pathway using JAK inhibitors and monoclonal antibodies against Type I IFNs. JAK inhibitors have shown promise in treating DM, particularly in refractory cases. However, more research is needed to fully understand their efficacy and safety profiles in IIMs. The review concludes by highlighting the importance of ongoing research in this area and the potential for new targeted therapies in treating IIMs.

Inflammatory myopathy is classified into primary autoimmune myositis and secondary myositis due to various factors, such as drugs and autoimmune connective tissue diseases. Autoimmune myositis mainly consists of dermatomyositis, antisynthetase syndrome-associated myositis, immune-mediated necrotizing myopathy, and inclusion body myositis. This review aims to provide insights into muscle pathology for clinical practice and an understanding of pathophysiology in inflammatory myopathy by summarizing current knowledge about the pathology of each subform of autoimmune myositis and some secondary myositis. Dermatomyositis is associated with type I interferon upregulation. Expression of myxovirus resistance protein A (a type I interferon-induced protein) in myofibers is utilized as a sensitive diagnostic marker. Antisynthetase syndrome-associated myositis is morphologically characterized by perifascicular necrosis. A recent study suggests the presence of a characteristic immunological micromilieu suitable for plasma cells in the skeletal muscle tissue. Immune-mediated necrotizing myopathy features an active necrotic and regenerating process. In inclusion body myositis, inflammatory cellular infiltration and rimmed vacuoles reflecting autophagy disruption are observed. The lymphocytes invading myofibers are composed of a highly differentiated T-cell population, which is considered a potential therapeutic target.

Recent studies have highlighted the importance of microglia as key immunomodulators in a variety of neuropsychiatric diseases. Postmortem brain analysis and positron emission tomography are representative research approaches to assess microglial activation in human patients and this research has revealed microglial activation in the brains of patients with various neuropsychiatric disorders. However, only limited aspects of microglial activation can be assessed with these methods. To overcome the technical and ethical limitations of collecting human-derived microglia in brain biopsies, we first developed a method to generate directly induced microglia-like (iMG) cells from fresh human peripheral blood monocytes in 2014. These iMG cells can be used to perform dynamic morphological and molecular analyses regarding phagocytic capacity and cytokine release following stress stimulation at the cellular level. Patient-derived iMG cells can potentially serve as an important surrogate marker for estimating microglial activation in the human brain, and may provide previously unknown insights into the dynamic pathophysiology of microglia in patients with neuropsychiatric disorders. Thus, the iMG-based technology could be used as a valuable reverse translational tool and provide new insights into the dynamic molecular pathophysiology of microglia in a wide variety of psychiatric and physical disorders.

Blood–tissue barriers play crucial roles in specialized tissues such as the central nervous system (CNS), eye, testis, and placenta. Tissue-resident macrophages in these tissues are indispensable for maintaining tissue homeostasis and responding to pathological conditions. Recent advances in high-throughput and high-dimensional single-cell analysis techniques, coupled with fate-mapping tools, have revealed a remarkable diversity of tissue-resident macrophages at the blood–tissue barrier. However, while comprehensive expression profiling has revealed the heterogeneity of macrophages within individual tissues, the commonalities of macrophages across anatomically similar structures like blood–tissue barriers remain poorly understood. This review focuses on the diversity and functional specialization of macrophages in tissues with blood–tissue barriers, highlighting recent insights into their anatomical distribution, developmental origins, phenotypic characteristics, and roles in maintaining tissue homeostasis. These findings may deepen our understanding of macrophage adaptation mechanisms in tissues with blood–tissue barriers, potentially leading to improved therapies for related disorders. Furthermore, examining the similarities and differences of macrophages across tissues may elucidate the molecular underpinnings of tissue-specific adaptation mechanisms and functional specialization.

Stroke and traumatic brain injury leave many survivors with permanent neurological disabilities, and the development of therapeutics to enhance functional recovery is needed. Both residential and infiltrating immune cells participate in the acute inflammation after brain injury, exacerbating functional outcomes; however, some immune cells have been reported to alter their characteristic to a reparative phenotype. This review focused on the recent findings of the reparative immunity of myeloid cells. Functional recovery after injury is achieved through the combination of resolution of inflammation, reorganization of neuronal network, white matter repair, angiogenesis and extracellular matrix reorganization. In each process, myeloid cells play vital roles in leading to functional recovery. Further research on the diversity of immune cells implicated in neural repair will be promising to develop therapeutics enhancing functional recovery after brain tissue injuries.