Identification of CSF biomarkers by proteomics in Guillain-Barré syndrome

CSF Diagnostics: A Potentially Valuable Tool in Neurodegenerative and Inflammatory Disorders Involving Motor Neurons: A Review

Cerebrospinal fluid (CSF) diagnostics has emerged as a valid tool for a variety of neurological diseases. However, CSF diagnostics has been playing a subordinate role in the diagnosis of many neurological conditions. Thus, in the multitude of neuromuscular diseases in which motor neurons are affected, a CSF sample is rarely taken routinely. However, CSF diagnostics has the potential to specify the diagnosis and monitor the treatment of neuromuscular disorders. In this review, we therefore focused on a variety of neuromuscular diseases, among them amyotrophic lateral sclerosis (ALS), peripheral neuropathies, and spinal muscular atrophy (SMA), for which CSF diagnostics has emerged as a promising option for determining the disease itself and its progression. We focus on potentially valuable biomarkers among different disorders, such as neurofilaments, cytokines, other proteins, and lipids to determine their suitability, differentiating between different neurological disorders and their potential to determine early disease onset, disease progression, and treatment outcome. We further recommend novel approaches, e.g., the use of mass spectrometry as a promising alternative techniques to standard ELISA assays, potentially enhancing biomarker significance in clinical applications.

Assessment of Expression of SOCS Genes in Acquired Immune-Mediated Polyneuropathies

Acquired immune-mediated polyneuropathies are classified to some subtypes among them are acute and chronic inflammatory demyelinating polyradiculoneuropathies (AIDP and CIDP). These two conditions share some common signs and underlying mechanisms. Based on the roles of Suppressor of cytokine signaling (SOCS) genes in the modulation of immune system reactions, these genes might be involved in the pathogenesis of these conditions. We evaluated expression of SOCS1-3 and SOCS5 genes in the leukocytes of 32 cases of CIDP, 19 cases of AIDP and 40 age- and sex-matched controls using real time PCR method. The Bayesian regression model was used to estimate differences in mean values of genes expressions between cases and control group. Expression levels of SOCS1 and SOCS2 were significantly lower in male patients compared with controls. This sex-specific pattern was also observed for SOCS3 down-regulation. Based on the area under curve values in Receiver Operating Characteristics (ROC) curve, diagnostic powers of SOCS1, SOCS2, SOCS3 and SOCS5 genes in the mentioned disorder were 0.61, 0.73, 0.68 and 0.58, respectively. Expression of none of genes was correlated with age of enrolled cases. The current study shows evidences for participation of SOCS genes in the pathophysiology of acquired immune-mediated polyneuropathies.

Current Progress and Future Directions for Tau-Based Fluid Biomarker Diagnostics in Alzheimer's Disease

Despite continued efforts, there remain no disease-modifying drugs approved by the United States Food and Drug Administration (FDA) or European Medicines Agency (EMA) to combat the global epidemic of Alzheimer's disease. Currently approved medicines are unable to delay disease progression and are limited to symptomatic treatment. It is well established that the pathophysiology of this disease remains clinically silent for decades prior to symptomatic clinical decline. Identifying those at risk of disease progression could allow for effective treatment whilst the therapeutic window remains open for preservation of quality of life. This review aims to evaluate critically the current advances in the interpretation of tau-based biomarkers and their use to provide insights into the onset and progression of Alzheimer's disease, whilst highlighting important future directions for the field. This review emphasises the need for a more comprehensive analysis and interrogation of tau within biological fluids, to aid in obtaining a disease specific molecular signature for each stage of Alzheimer's disease. Success in achieving this could provide essential utility for presymptomatic patient selection for clinical trials, monitoring disease progression, and evaluating disease modifying therapies.

Trauma-Related Guillain-Barré Syndrome: Systematic Review of an Emerging Concept

Guillain-Barré syndrome (GBS) is mainly associated with preceding exposure to an infectious agent, although the precise pathogenic mechanisms and causes remain unknown. Increasing evidence indicates an association between trauma-related factors and GBS. Here, we performed a systematic review, summarized the current scientific literature related to the onset of GBS associated with trauma, and explored the possible pathogenesis. A literature search of various electronic databases was performed up to May 2020 to identify studies reporting diverse trauma-related triggers of GBS. Data were extracted, summarized descriptively, and evaluated with respect to possible mechanisms. In total, 100 publications, including 136 cases and 6 case series involving GBS triggered by injury, surgery, intracranial hemorrhage, and heatstroke, met our eligibility criteria. The median age of the patients was 53 [interquartile range (IQR) 45-63] years, and 72.1% of the patients were male. The median number of days between the trigger to onset of GBS symptoms was 9 (IQR 6.5-13). Overall, 121 patients (89.0%) developed post-injury/surgical GBS, whereas 13 (9.6%) and 2 (1.5%) patients had preexisting spontaneous intracranial hemorrhage and heatstroke, respectively. The main locations of injury or surgeries preceding GBS were the spine and brain. Based on available evidence, we highlight possible mechanisms of GBS induced by these triggers. Moreover, we propose the concept of "trauma-related GBS" as a new research direction, which may help uncover more pathogenic mechanisms than previously considered for typical GBS triggered by infection or vaccination.