Oligoclonal bands and periventricular lesions in multiple sclerosis will not increase blood-brain barrier permeability

Exploring the theranostic potentials of miRNA and epigenetic networks in autoimmune diseases: A comprehensive review

BACKGROUND

Autoimmune diseases (AD) are severe pathophysiological ailments that are stimulated by an exaggerated immunogenic response towards self-antigens, which can cause systemic or site-specific organ damage. An array of complex genetic and epigenetic facets majorly contributes to the progression of AD, thus providing significant insight into the regulatory mechanism of microRNA (miRNA). miRNAs are short, non-coding RNAs that have been identified as essential contributors to the post-transcriptional regulation of host genome expression and as crucial regulators of a myriad of biological processes such as immune homeostasis, T helper cell differentiation, central and peripheral tolerance, and immune cell development.

AIMS

This article tends to deliberate and conceptualize the brief pathogenesis and pertinent epigenetic regulatory mechanism as well as miRNA networks majorly affecting five different ADs namely rheumatoid arthritis (RA), type 1 diabetes, multiple sclerosis (MS), systemic lupus erythematosus (SLE) and inflammatory bowel disorder (IBD) thereby providing novel miRNA-based theranostic interventions.

RESULTS & DISCUSSION

Pertaining to the differential expression of miRNA attributed in target tissues and cellular bodies of innate and adaptive immunity, a paradigm of scientific expeditions suggests an optimistic correlation between immunogenic dysfunction and miRNA alterations.

CONCLUSION

Therefore, it is not astonishing that dysregulations in miRNA expression patterns are now recognized in a wide spectrum of disorders, establishing themselves as potential biomarkers and therapeutic targets. Owing to its theranostic potencies, miRNA targets have been widely utilized in the development of biosensors and other therapeutic molecules originating from the same.

Cerebrospinal fluid oligoclonal bands in Chinese patients with multiple sclerosis: the prevalence and its association with clinical features

Background

Cerebrospinal fluid oligoclonal band (CSF-OCB) is an established biomarker in diagnosing multiple sclerosis (MS), however, there are no nationwide data on CSF-OCB prevalence and its diagnostic performance in Chinese MS patients, especially in the virtue of common standard operation procedure (SOP).

Methods

With a consensus SOP and the same isoelectric focusing system, we conducted a nationwide multi-center study on OCB status in consecutively, and recruited 483 MS patients and 880 non-MS patients, including neuro-inflammatory diseases (NID, n = 595) and non-inflammatory neurological diseases (NIND, n=285). Using a standardized case report form (CRF) to collect the clinical, radiological, immunological, and CSF data, we explored the association of CSF-OCB positivity with patient characters and the diagnostic performance of CSF-OCB in Chinese MS patients. Prospective source data collection, and retrospective data acquisition and statistical data analysis were used.

Findings

369 (76.4%) MS patients were OCB-positive, while 109 NID patients (18.3%) and 6 NIND patients (2.1%) were OCB-positive, respectively. Time from symptom onset to diagnosis was significantly shorter in OCB-positive than that in OCB-negative MS patients (13.2 vs 23.7 months, P=0.020). The prevalence of CSF-OCB in Chinese MS patients was significantly higher in high-latitude regions (41°-50°N)(P=0.016), and at high altitudes (>1000m)(P=0.025). The diagnostic performance of CSF-OCB differentiating MS from non-MS patients yielded a sensitivity of 76%, a specificity of 87%.

Interpretation

The nationwide prevalence of CSF-OCB was 76.4% in Chinese MS patients, and demonstrated a good diagnostic performance in differentiating MS from other CNS diseases. The CSF-OCB prevalence showed a correlation with high latitude and altitude in Chinese MS patients.

Recent progress in epidemiology, clinical features, and therapy of multiple sclerosis in China

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system characterized by inflammation, demyelination, and neurodegeneration. It mainly affects young adults, imposing a heavy burden on families and society. The epidemiology, clinical features, and management of MS are distinct among different countries. Although MS is a rare disease in China, there are 1.4 billion people in China, so the total number of MS patients is not small. Because of the lack of specific diagnostic biomarkers for MS, there is a high misdiagnosis rate in China, as in other regions. Due to different genetic backgrounds, the clinical manifestations of MS in Chinese are different from those in the West. Herein, this review aims to summarize the disease comprehensively, including clinical profile and the status of disease-modifying therapies in China based on published population-based observation and cohort studies, and also to compare with data from other countries and regions, thus providing help to develop diagnostic guideline and the novel therapeutic drugs. Meanwhile, we also discuss the problems and challenges we face, specifically for the diagnosis and treatment of MS in the middle- and low-income countries.

Oligoclonal Band Status and Features of Radiological and Clinical Findings in Patients with Multiple Sclerosis in Lithuania

Background and Objectives: Multiple sclerosis (MS) is a widely spread and debilitating disease with 2.8 million people worldwide currently affected. However, the exact pathogenesis of the disease and its progression remains incompletely understood. According to the revised McDonald criteria, cerebrospinal fluid oligoclonal bands (CSF OCBs) magnetic resonance imaging (MRI) results, in conjunction with clinical presentation, remain the gold standard of MS diagnostics. Therefore, this study aims to evaluate the association between CSF OCB status and features of radiological and clinical findings in patients with multiple sclerosis in Lithuania. Materials and Methods: The selection of 200 MS patients was performed in order to find associations between CSF OCB status, MRI data and various disease features. The data were acquired from outpatient records and a retrospective analysis was performed. Results: OCB positive patients were diagnosed with MS earlier and had spinal cord lesions more frequently than OCB negative patients. Patients with lesions in the corpus callosum had a greater increase in the Expanded Disability Status Scale (EDSS) score between their first and last visit. Patients with brainstem lesions had higher EDSS scores during their first and last visit. Even so, the progression of the EDSS score was not greater. The time between the first symptoms and diagnosis was shorter for patients who had juxtacortical lesions than patients who did not. Conclusions: CSF OCBs and MRI data remain irreplaceable tools when diagnosing multiple sclerosis as well as prognosing the development of the disease and disability.

From cells to organoids: The evolution of blood-brain barrier technology for modelling drug delivery in brain cancer

Brain cancer remains the deadliest cancer. The blood-brain barrier (BBB) is impenetrable to most drugs and is a complex 3D network of multiple cell types including endothelial cells, astrocytes, and pericytes. In brain cancers, the BBB becomes disrupted during tumor progression and forms the blood-brain tumor barrier (BBTB). To advance therapeutic development, there is a critical need for physiologically relevant BBB in vitro models. 3D cell systems are emerging as valuable preclinical models to accelerate discoveries for diseases. Given the versatility and capability of 3D cell models, their potential for modelling the BBB and BBTB is reviewed. Technological advances of BBB models and challenges of in vitro modelling the BBTB, and application of these models as tools for assessing therapeutics and nano drug delivery, are discussed. Quantitative, in vitro BBB models that are predictive of effective brain cancer therapies will be invaluable for accelerating advancing new treatments to the clinic.

Silent progression of brain atrophy in aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder

OBJECTIVE

To investigate longitudinal brain atrophy in patients with neuromyelitis optica spectrum disorder (NMOSD).

METHODS

We investigated the longitudinal brain atrophy rate in patients with aquaporin-4 antibody-positive NMOSD (AQP4+NMOSD) and those with multiple sclerosis (MS) in a retrospective cohort study. Brain volume was calculated with statistical parametric mapping-12.

RESULTS

We enrolled 36 patients with AQP4+NMOSD and 60 with MS. Patients with NMOSD were older and had a higher Kurtzke's expanded disability status scale score at baseline MRI compared with those with MS. Disease duration, annual relapse rate and intervals from the last attack and from disease-modifying drugs initiation were not significantly different between the two groups. Lower normalised lesion volume and higher normalised white matter volume were found in patients with NMOSD compared with those with MS at baseline MRI. However, the annualised atrophy rate of normalised brain volume was similar between the NMOSD (median 0.47; IQR 0.75; p=0.49) and MS (median 0.46; IQR 0.84) groups. After adjustment of age and the presence of clinical relapse, no differences of the annualised atrophy rate of normalised brain volume also were found for NMOSD and MS. Patients with AQP4+NMOSD with long cord lesion showed higher annualised atrophy rate of normalised grey matter volume compared with those without long cord lesion.

CONCLUSIONS

Silent progression of brain atrophy was present in patients with AQP4+NMOSD, as shown in patients with MS, even in the clinically inactive age-matched cases. Subclinical dying back degeneration may explain the brain atrophy in patients with AQP4 +NMOSD.

MicroRNA in multiple sclerosis

Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS). Despite a complex pathogenesis, it appears that an imbalanced immune system plays an important role in the disease process. MicroRNAs (miRNAs) are comprised of short non-coding single-stranded molecules mainly involved in regulating gene expression through the inhibition of transcription and translation. miRNAs are key regulatory molecules in the nucleus and participate in the proliferation, differentiation, and apoptosis of various cells throughout the body. Recent studies, however, have found that miRNAs are also involved in MS pathogenesis, mainly affecting glial cells and peripheral immune cells. Fortunately, miRNAs are highly stable and have high specificity in peripheral body fluids. Accordingly, these molecules have become new diagnostic and therapeutic targets. The present review discusses the role of miRNAs in the pathogenesis of MS. We highlight the potential of miRNAs as new biomarkers of MS and potential therapeutic agents.

Integrating Biosensors in Organs-on-Chip Devices: A Perspective on Current Strategies to Monitor Microphysiological Systems

Organs-on-chip (OoC), often referred to as microphysiological systems (MPS), are advanced in vitro tools able to replicate essential functions of human organs. Owing to their unprecedented ability to recapitulate key features of the native cellular environments, they represent promising tools for tissue engineering and drug screening applications. The achievement of proper functionalities within OoC is crucial; to this purpose, several parameters (e.g., chemical, physical) need to be assessed. Currently, most approaches rely on off-chip analysis and imaging techniques. However, the urgent demand for continuous, noninvasive, and real-time monitoring of tissue constructs requires the direct integration of biosensors. In this review, we focus on recent strategies to miniaturize and embed biosensing systems into organs-on-chip platforms. Biosensors for monitoring biological models with metabolic activities, models with tissue barrier functions, as well as models with electromechanical properties will be described and critically evaluated. In addition, multisensor integration within multiorgan platforms will be further reviewed and discussed.

Impact of intrathecal IgG synthesis on neurological disability in patients with multiple sclerosis

BACKGROUND

The association between routine laboratory findings, including cerebrospinal fluid biomarkers, and neurological outcomes in patients with multiple sclerosis (MS) has not been fully elucidated. In this study, we evaluated blood and cerebrospinal fluid (CSF) analysis results at diagnosis and before treatment in patients with MS and assessed their correlations with neurological outcomes.

MATERIALS AND METHODS

In this study, 38 consecutive patients with MS (36 with relapsing-remitting MS and 2 with primary progressive MS) were recruited. Before treatment, all patients underwent routine CSF analysis at the time of diagnosis, including evaluation of albumin and immunoglobulin G (IgG) levels. The association between laboratory data and neurological outcomes was comprehensively evaluated. Subsequent neurological outcome was assessed by using the Expanded Disability Status Scale (EDSS) score at 1 year and 5 years after diagnosis and relapse frequency in the first year and in the first 5 years.

RESULTS

The IgG level in the CSF (rho = 0.46, p = 0.004), oligoclonal band count (rho = 0.61, p = 0.006), ratio of IgG and total protein in CSF (rho = 0.59, p < 0.0001), and ratio of IgG and albumin in CSF (rho = 0.67, p < 0.0001) showed moderate to strong correlations with the subsequent EDSS score 1 year after diagnosis. These variables still showed significant correlations with EDSS 5 years later. Albumin and lactate dehydrogenase levels in CSF did not correlate with the subsequent EDSS score. Relapse frequency did not correlate with any of the studied serum and CSF biomarkers.

CONCLUSION

IgG levels in CSF at MS diagnosis are significantly correlated with the level of neurological disability independent of the relapse frequency. Markers of intrathecal IgG synthesis, such as the IgG index, are useful in estimating the present and subsequent clinical severity in patients with MS.

Recent Progress in Microfluidic Models of the Blood-Brain Barrier

The blood-brain barrier (BBB) is a critical physical and chemical barrier that maintains brain homeostasis. Researchers in academia and industry are highly motivated to develop experimental models that can accurately mimic the physiological characteristics of the BBB. Microfluidic systems, which manipulate fluids at the micrometer scale, are ideal tools for simulating the BBB microenvironment. In this review, we summarized the progress in the design and evaluation of microfluidic in vitro BBB models, including advances in chip materials, porous membranes, the use of endothelial cells, the importance of shear stress, the detection specific markers to monitor tight junction formation and integrity, measurements of TEER and permeability. We also pointed out several shortcomings of the current microfluidic models. The purpose of this paper is to let the readers understand the characteristics of different types of model design, and select appropriate design parameters according to the research needs, so as to obtain the best experimental results. We believe that the microfluidics BBB models will play an important role in neuroscience and pharmaceutical research.

Disruption of the Blood-Brain Barrier During Neuroinflammatory and Neuroinfectious Diseases

As the organ of highest metabolic demand, utilizing over 25% of total body glucose utilization via an enormous vasculature with one capillary every 73 μm, the brain evolves a barrier at the capillary and postcapillary venules to prevent toxicity during serum fluctuations in metabolites and hormones, to limit brain swelling during inflammation, and to prevent pathogen invasion. Understanding of neuroprotective barriers has since evolved to incorporate the neurovascular unit (NVU), the blood-cerebrospinal fluid (CSF) barrier, and the presence of CNS lymphatics that allow leukocyte egress. Identification of the cellular and molecular participants in BBB function at the NVU has allowed detailed analyses of mechanisms that contribute to BBB dysfunction in various disease states, which include both autoimmune and infectious etiologies. This chapter will introduce some of the cellular and molecular components that promote barrier function but may be manipulated by inflammatory mediators or pathogens during neuroinflammation or neuroinfectious diseases.

Disruption of blood-brain barrier integrity associated with brain lesions in Chinese neuromyelitis optica spectrum disorder patients

OBJECTIVE

The aims of this study were to report brain characteristic abnormalities and to evaluate the relationship of blood-brain barrier (BBB) disruption and brain lesions in Chinese patients with NMOSD.

METHODS

Brain magnetic resonance imaging characteristics and cerebrospinal fluid (CSF) laboratory tests of 121 patients with NMOSD at acute attack were reviewed retrospectively. Qalb (CSF albumin/serum albumin) was used for assessment of disruption of BBB.

RESULTS

Brain MRI abnormalities were observed in 36.4% (44/121) of the NMOSD patients. Thirty patients (25%) showed typical-NMOSD abnormalities, including dorsal medulla lesions (n = 16, 13.2%), brainstem/cerebellum (n = 11, 9.1%), thalamus/hypothalamus (n = 3, 2.5%), periventricular white matter lesions (n = 4, 3.3%) hemispheric white matter (n = 4, 3.3%). Twenty-five patients (20.7%) had nonspecific lesions. Compared to the NMOSD patients without brain lesion, the proportion of patients who had abnormal BBB permeability was significantly higher in the abnormal brain MRI group (47.7% vs. 27.3%, P < 0.05). BBB permeability was not correlated to distribution of brain lesions or enhancement lesions. Qalb was associated with higher Expanded Disability Status Scale scores (r = 0.689, P < 0.05).

CONCLUSIONS

Brain lesions are common in NMOSD patients. Marker of BBB permeability is associated with brain lesion and EDSS scores of NMOSD.

[Brain atrophy and perfusion changes in patients with remitting and secondary progressive multiple sclerosis]

AIM

To study the relationship of brain atrophy and changes in perfusion with an increase in the level of disability in patients with multiple sclerosis (MS).

MATERIAL AND METHODS

Twenty patients with remitting MS, 20 patients with secondary progressive multiple sclerosis (SPMS) and 20 healthy people were studied. The level of neurological deficit was assessed with EDSS and cognitive status with PASAT. MRI of the brain (standard impulse sequences and 3D-T1-MPR for voxel MRI-morphometry) and perfusion computed tomography with the assessment of visually intact white matter (VIWM) and thalamus were performed.

RESULTS

Compared to the control group, patients with MS had a significant atrophy of subcortical gray matter. Patients with SPMS in addition had an atrophy of some cortical areas which was correlated with EDSS scores (p<0.05). The correlation between cognitive impairment and the volume of the left inferior parietal lobule (r=0.677; p=0.011) and worsening of perfusion of VIWM of frontal and parietal lobes, thalamus on both sides was observed in patients with SPMS compared to those with remitting MS. That was correlated with cognitive performance assessed by PASAT.

CONCLUSION

Patterns of atrophy distribution in different types of MS were determined. The level of disability is correlated with the severity of brain atrophy. Hypoperfusion of VIWM that was correlated with cognitive impairment was found in patients with SPMS.

Peripheral blood monocyte count at onset may affect the prognosis in multiple sclerosis

Multiple sclerosis (MS) is a demyelinating neurological disease with unknown causes. In this study, we comprehensively studied blood cell counts in the early phase of MS and compared their values with eventual prognostic variables. We found that the blood monocyte count in the early phase of MS was robustly associated with the clinical severity of MS (rho = 0.64; p = 0.0002) but that the counts of the other blood cells were not associated with severity. This correlation between monocyte count and severity was not observed in neuromyelitis optica. In conclusion, blood monocytes could be a candidate for the prognostic prediction of MS.