Clinical and Experimental Neuroimmunology最新文献

Alzheimer's disease (AD) is the leading cause of dementia, with the number of patients with AD expected to double in the next quarter-century. Brain deposition of amyloid-β (Aβ) and tau proteins is a necessary but insufficient condition for AD pathogenesis. There is also growing evidence to suggest that chronic neuroinflammation due to excessive microglial activation and astrocyte dysfunction exacerbates the pathophysiology of AD, but the factors that disrupt these homeostatic processes remain unclear. Research into AD pathophysiology has shown interest in the changes in adaptive T-cells, which play a pivotal role in immunity. The immune alterations in the peripheral circulation and increased blood–brain-barrier permeability observed in patients with AD, even in the initial stages of the disease, require investigation of the immune mechanisms resulting from T-cell infiltration into the central nervous system (CNS) during disease initiation and exacerbation. Since T-cells play a two-faceted role in the CNS immune response, including pathogenic and neuroprotective roles, the role of T-cells in AD has been debated. Memory T-cells reside in the brain and communicate with glial cells and neurons. In this review, the role of immune responses in AD is discussed, focusing on the contribution of T-cells.

Neuroinflammation, which is mediated by microglia, astrocytes, and infiltrated immune cells and leads to the subsequent production of proinflammatory molecules, is associated with the pathomechanism of Alzheimer's disease (AD). As the incidence of AD is higher in females than males, multiple studies have focused on the relationship between sex hormones and AD pathology. Androgen and estrogen receptors are expressed throughout the brain, including the hippocampus; thus, both sex hormones may regulate brain function, including cognitive function. Endogenous sex hormone levels are depleted by aging and cancer therapies, including prostate cancer and breast cancer therapies. Previous cohort studies have revealed that these conditions may also increase the risk of developing AD. Here we review previous findings from epidemiologic and preclinical studies on AD and provide an overview of the roles of sex hormones as risk factors of AD and regulators of AD pathology, including neuroinflammation. Furthermore, we discuss the therapeutic potential of sex hormone supplementation as a preventive or therapeutic treatment for AD based on the results of randomized control trials.

Alzheimer's disease (AD) is the most common neurocognitive disorder. Various factors are intricately intertwined before clinical symptoms appear, although both amyloid-β peptide deposition and neurofibrillary tangle formation (i.e. pathological hallmarks of the AD brain) are established. Among such factors, glial responses have been increasingly recognized as important roles in the progression of these pathologies and viewed as one component of the AD continuum. However, the detailed molecular and cellular mechanisms of glial function underlying AD pathogenesis remain to be elucidated. Recent studies showed that peripheral immunity, gut microbiota or environmental factors influence brain pathophysiologies through communication with glial cells in the brain. This disease complexity makes understanding AD etiology difficult and hinders the development of effective therapeutic strategies to tackle this disease. Conversely, aged patients often suffer from multiple – not a single – diseases as multimorbidity, and AD pathogenesis might be related to pathologies caused by other diseases. Hence, investigating AD as a systemic disease has become critical for identifying therapeutic interventions. This review aimed to summarize current knowledge on AD research and share perspectives for understanding glial functions regarding AD pathophysiology.

We present a case of acute partial transverse myelitis (TM) that developed 6 d following covaccination with a bivalent COVID-19 booster vaccine and quadrivalent influenza vaccine. Although initial imaging of the thoracic spine was nonspecific, repeat magnetic resonance imaging (MRI) showed a T2 hyperintense lesion with contrast enhancement, consistent with TM. The risk of rare but catastrophic neurologic complications following the bivalent COVID-19 booster vaccine and/or covaccination with COVID-19 and influenza vaccines is the subject of ongoing investigation in the medical community.

The revised Japanese clinical guidelines for myasthenia gravis (MG) and Lambert–Eaton myasthenic syndrome (LEMS) were published in 2022. The notable points in these guidelines (GLs) are as follows: (i) these are the first Japanese GLs to include a description of LEMS; (ii) diagnostic criteria of MG are revised to lessen the incidence of false negative patients; (iii) MG is divided into six clinical subtypes; (iv) a high-dose oral steroid regimen with escalation and de-escalation schedule is not recommended by the GLs; (v) the GLs promote the early fast-acting treatment strategy initially proposed in the previous GLs; (vi) refractory MG is defined; (vii) the use of molecular targeted drugs is included; (viii) diagnostic criteria of LEMS are proposed; and (ix) treatment algorithms for both MG and LEMS are presented. These new GLs are expected to improve the patients' quality of life and will serve to bridge the present era with the molecular targeted treatment eras.