Oxidization-driven polyamine probe boosts biosensor selectivity via a proton sponge effect regulation strategy.

The signs and symptoms associated with fungal meningitis are similar to those seen with more common bacterial infections. In this study, we investigate whether Aspergillus or Candida DNA can be detected in cerebrospinal fluid (CSF) samples from patients suspected of fungal meningitis using real-time PCR assay. From April 2007 to November 2009, we evaluated CSF samples and sera from patients with risk factors for cerebral fungal meningitis in Nemazi Hospital, Shiraz University of Medical Sciences, Iran, by real-time PCR assay and routine mycological studies (direct microscopy examination and culture). Two CSF and two serum samples from each patient were examined. CSF and serum samples from 38 patients (total: 152) suspected of fungal meningitis were examined. India ink staining and KOH smear were negative for all patients. C. albicans was isolated from two CSF samples. There were ten patients with positive real-time PCR results in their CSF samples: three patients had C. albicans, one with C. glabrata, four with Aspergillus species and two with both C. albicans and Aspergillus species DNA. Four patients had positive serum results for Aspergillus or Candida infections. Considering the findings, it seems that molecular examination can help in the diagnosis of fungal meningitis in patients with clinical and radiological presentations. Further studies should be conducted in other regions and settings to confirm these findings.

Osteopontin (OPN), which is highly expressed in malignant glioblastoma (GBM), possesses inflammatory activity modulated by proteolytic cleavage by thrombin and plasma carboxypeptidase B2 (CPB2) at a highly conserved cleavage site. Full-length OPN (OPN-FL) was elevated in cerebrospinal fluid (CSF) samples from all cancer patients compared with noncancer patients. However, thrombin-cleaved OPN (OPN-R) and thrombin/CPB2-double-cleaved OPN (OPN-L) levels were markedly increased in GBM and non-GBM gliomas compared with systemic cancer and noncancer patients. Cleaved OPN constituted ∼23 and ∼31% of the total OPN in the GBM and non-GBM CSF samples, respectively. OPN-R was also elevated in GBM tissues. Thrombin-antithrombin levels were highly correlated with cleaved OPN, but not OPN-FL, suggesting that the cleaved OPN fragments resulted from increased thrombin and CPB2 in this extracellular compartment. Levels of VEGF and CCL4 were increased in CSF of GBM and correlated with the levels of cleaved OPN. GBM cell lines were more adherent to OPN-R and OPN-L than OPN-FL. Adhesion to OPN altered gene expression, in particular genes involved with cellular processes, cell cycle regulation, death, and inflammation. OPN and its cleaved forms promoted motility of U-87 MG cells and conferred resistance to apoptosis. Although functional mutation of the RGD motif in OPN largely abolished these functions, OPN(RAA)-R regained significant cell binding and signaling function, suggesting that the SVVYGLR motif in OPN-R may substitute for the RGD motif if the latter becomes inaccessible. OPN cleavage contributes to GBM development by allowing more cells to bind in niches where they acquire anti-apoptotic properties.

Little is known about the penetration and bioactivity of systemically administered programmed cell death 1 (PD-1) antibodies in the central nervous system. Such information is critical for advancing checkpoint antibody therapies for treatment of brain tumors. To evaluate pembrolizumab concentrations and PD-1 blockade on T cells in the cerebrospinal fluid (CSF) after intravenous administration. Cerebrospinal fluid and blood samples were collected from 10 adult patients with high-grade gliomas who were participating in clinical trials of intracranially administered chimeric antigen receptor (CAR) T cells and intravenous pembrolizumab at City of Hope in Duarte, California, from 2017 through 2019. Neuropharmacokinetic and immunologic correlative studies were performed on CSF and serum samples. Pembrolizumab, 200 mg, was given intravenously every 3 weeks with a median of 2 cycles (range, 1-8). CAR T cells were administered intracranially every 1 to 4 weeks. Cerebrospinal fluid and blood samples were collected on the day of CAR T-cell administration and then 24 hours later for a total of 100 paired samples. Pembrolizumab concentrations were measured by enzyme-linked immunosorbent assay, PD-1 blocking on T cells by flow cytometry, and results of PD-1 blockade on CAR T-cell function by in vitro tumor rechallenge assays. Of the 10 patients included in this study, the mean (SD) age was 45.7 (11.0) years, and 6 (60%) were women. Steady-state pembrolizumab concentrations in the CSF were achieved by 24 hours after initial intravenous administration, with a mean CSF:serum ratio of 0.009 (95% CI, 0.004-0.014). The CSF concentrations of pembrolizumab effectively blocked PD-1 on both endogenous T cells and intracranially administered CAR T cells in the CSF, with flow cytometric detection of surface PD-1 on the T cells decreasing from a mean (SD) of 39.3% (20.2%) before pembrolizumab to a mean (SD) of 3.8% (5.8%) 24 hours after pembrolizumab infusion. Steady-state concentrations in the CSF were maintained throughout the 21-day cycle of pembrolizumab, as was the PD-1 blocking effect, evidenced by no increase in detectable surface PD-1 on T cells in the CSF during that time period. Incubation of PD-1-expressing T cells with CSF samples from patients treated with pembrolizumab also resulted in PD-1 blockade. Results of this study demonstrate steady-state concentrations of pembrolizumab in CSF after intravenous administration as well as CSF concentrations that are sufficient for blocking PD-1 on endogenous and adoptively transferred T cells. This provides mechanistic insight regarding the ability of systemically administered PD-1 blocking antibodies to modulate T-cell activity in the brain.

Objective. To investigate the presence of arbovirus genomes in cerebrospinal fluid (CSF) samples from children suspected of viral neurological infection, associating the results with clinical manifestations and analyzing the CSF. Methods. The cross-sectional study included CSF samples from 184 children and teenagers aged 1 day to 18 years old, with negative CSF microbiology tests. Molecular tests were carried out to detect arboviruses in the CSF. Results. Among 184 children, the genome of dengue (DENV) and zika (ZIKV) viruses were found in 44 CSF samples (23.9%) (CI 95% 17.7%-30.1%). Among those samples, 59% were positive for dengue virus, 38.6% for ZIKV, and 2.3% coinfection of DENV plus ZIKV was observed. In 67 patients with suspected infection/sepsis, 23.9% of CSF samples were positive; among 26 meningitis, 11.5% had positive results; in 22 hydrocephaly, 22.7% were positive; in 20 with convulsion, 25% had CSF positive, in 4 with encephalitis 25% were positive; in 5 intracranial hypertension, 60% were positive; 1 in 3 cases, 33.3% each, presented with neuritis and meningoencephalitis were positive; the 2 Guillain-Barré syndrome were positive. Pleocytosis occurred in 25% of positive cases, and antibiotics were used in 56.8%. We found a positivity of neurological infection by ZIKV and DENV in children even after the outbreak. Most positive samples did not show biochemical changes in the CSF. Conclusion. Molecular tests in CSF of children with neurological conditions contribute to the identification of the viral etiology, leading to less use of unnecessary antibiotics and reducing hospital stays.Keywords: arboviruses; dengue; zika; children; molecular detection; central nervous

A technique for simultaneous sampling of cerebrospinal and brain extracellular fluid in unanaesthetized rabbits

RETRACTED: Remission of Subacute Psychosis in a COVID-19 Patient With an Antineuronal Autoantibody After Treatment With Intravenous Immunoglobulin

The intracellular delivery of nucleic acids and proteins remains a key challenge in the development of biological therapeutics. In gene therapy, the inefficient delivery of small interfering RNA (siRNA) to the cytosol by lipoplexes or polyplexes is often ascribed to the entrapment and degradation of siRNA payload in the endosomal compartments. A possible mechanism by which polyplexes rupture the endosomal membrane and release their nucleic acid cargo is commonly defined as the "proton sponge effect". This is an osmosis-driven process triggered by the proton buffering capacityof polyplexes. Herein, we investigate the molecular basis of the "proton sponge effect" through direct visualization of the siRNA trafficking process, including analysis of individual polyplexes and endosomes, using stochastic optical reconstruction microscopy. We probe the sequential siRNA trafficking steps through single molecule super-resolution analysis of subcellular structures, polyplexes, and silencing RNA molecules. Specifically, individual intact polyplexes released in the cytosol upon rupture of the endosomes, the damaged endosomal vesicles, and the disassembly of the polyplexes in the cytosol areexamined. We findthat the architecture of the polyplex and the rigidity of the cationic polymer chains are crucial parameters that control the mechanism of endosomal escape driven by the proton sponge effect. We provide evidence that in highly branched and rigid cationic polymers, such as glycogen or polyethylenimine, immobilized on silica nanoparticles, the proton sponge effect is effective in inducing osmotic swelling and rupture of endosomes.

Anti-IgLON5 disease is a rare chronic autoimmune disorder characterized by IgLON5 autoantibodies predominantly of the IgG4 subclass. Distinct pathogenic effects were described for anti-IgLON5 IgG1 and IgG4, however, with uncertain clinical relevance. IgLON5-specific IgG1-4 levels were measured in 46 sera and 20 cerebrospinal fluid (CSF) samples from 13 HLA-subtyped anti-IgLON5 disease patients (six females, seven males) using flow cytometry. Intervals between two consecutive serum or CSF samplings (31 and 10 intervals, respectively) were categorized with regard to the immunomodulatory treatment active at the end of the interval, changes of anti-IgLON5 IgG1 and IgG4 levels, and disease severity.Intrathecal anti-IgLON5 IgG4 synthesis (IS) was assessed using a quantitative method. The median age at onset was 66 years (range: 54-75), disease duration 10 years (range: 15-156 months), and follow-up 25 months (range: 0-83). IgLON5-specific IgG4 predominance was observed in 38 of 46 (83%) serum and 11 of 20 (55%) CSF samples. Anti-IgLON5 IgG4 levels prior clinical improvement in CSF but not serum were significantly lower than in those prior stable/progressive disease. Compared to IgLON5 IgG4 levels in serum, CSF levels in HLA-DRB1*10:01 carriers were significantly higher than in non-carriers. Indeed, IgLON5-specific IgG4 IS was demonstrated not only in four of five HLA-DRB1*10:01 carriers but also in one non-carrier. Immunotherapy was associated with decreased anti-IgGLON5 IgG serum levels. In CSF, lower anti-IgLON5 IgG was associated with immunosuppressive treatments used in combination, that is, corticosteroids and/or azathioprine plus intravenous immunoglobulins or rituximab. Our findings might indicate that CSF IgLON5-specific IgG4 isfrequently produced intrathecally, especially in HLA-DRB1*10:01 carriers.Intrathecally produced IgG4 may be clinically relevant. While manyimmunotherapies reduce serum IgLON5 IgG levels, more intense immunotherapies induce clinical improvement and may be able to target intrathecally produced anti-IgLON5 IgG. Further studies need to confirm whether anti-IgLON5 IgG4 IS is a suitable prognostic and predictive biomarker in anti-IgLON5 disease.

A 9-year-old spayed female German Shepherd dog with a history of orthopedic disease was presented to the North Carolina State University Veterinary Teaching Hospital for evaluation of recent, progressive, bilateral, hindlimb ataxia. Analysis of cisternal and lumbar cerebrospinal fluid (CSF) samples revealed normal total nucleated cell counts and a mild increase in protein concentration in the lumbar sample. In cytocentrifuged specimens of both CSF samples, aggregates of refractile, angular to irregular, pale blue to colorless, crystalline material were observed in the background. Some of the material appeared birefringent under polarized light. Differentials for the material included contrast agent, epidural anesthetics or other pharmacologic agents, or artifact introduced through sample processing, collection, or handling. Based on investigation of clinical and laboratory processes it was determined that tubes used to collect CSF in the hospital recently had been changed from additive-free glass tubes to silica-coated shatter-resistant plastic tubes (BD Vacutainer Plus serum tubes, silicone-coated, Becton Dickinson). A cytocentrifuged preparation of saline placed in a silica-coated tube contained crystalline material identical to that observed in the CSF samples; saline placed in an additive-free glass tube contained no material. In this case, we document the microscopic appearance of highly concentrated silica particles in cytocentrifuged preparations of CSF and underscore the importance of recognizing and identifying this artifact in cytologic preparations.

Exploration of the source of AQP4 antibody: Based on paired serum and cerebrospinal fluid samples from 98 patients.

Cerebrospinal fluid levels of chemokines in HIV infected patients with and without opportunistic infection of the central nervous system

BackgroundChemokines such as MIP-3β/CCL19 are important factors in the mechanism of cell migration and pathogenesis of central nervous system (CNS) inflammatory reactions. The hypothesis of this study is that CCL19, also known as MIP-3β, is involved in the pathogenesis of inflammatory and non-inflammatory CNS diseases of dogs. Experiments were performed on cerebrospinal fluid (CSF) and serum samples of dogs affected with steroid responsive meningitis-arteritis (SRMA) during the acute phase as well as during treatment. Dogs with SRMA were compared to dogs with presumed meningoencephalomyelitis of unknown origin (MUO), and both groups sub-categorized into dogs receiving no therapy and with patients receiving prednisolone therapy. Idiopathic epilepsy (IE), a group with normal CSF cell count, was used as a control. Additionally, dogs with intervertebral disc disease (IVDD) of varying severity were analyzed. Chemokine concentrations were determined by enzyme linked immunosorbent assay. Migration assays were performed on seven selected CSF samples using a disposable 96-well chemotaxis chamber.ResultsCCL19 was detectable in CSF samples of all dogs. Dogs with untreated SRMA and MUO displayed pronounced CCL19 elevations compared to the control group and patients receiving glucocorticosteroid treatment. CSF cell counts of untreated SRMA and MUO patients were significantly positively correlated with the CCL19 CSF concentration. IVDD patients also had elevated CCL19 concentration compared to controls, but values were considerably lower than in inflammatory CNS diseases. Selected CSF samples displayed chemotactic activity for mononuclear cells in the migration assay.ConclusionsCCL19 CSF concentrations were markedly elevated in patients affected with the neuroinflammatory diseases SRMA and MUO and showed a strong correlation with the CSF cell count. This chemokine may play an important role in the pathogenesis of SRMA and MUO. The elevation of CSF CCL19 in IVDD suggests that it may also be involved in the secondary wave of spinal cord injuries.

Detection of enteroviruses by polymerase chain reaction in urine samples of patients with aseptic meningitis.

Guiding Treatment and Clinical Management of Patients with CNS Lymphomas By Minimal-Invasive Detection of Circulating Tumor DNA in Cerebrospinal Fluid

Multiple sclerosis is an autoimmune disease of the central nervous system, with myelin degeneration and Relapsing-Remitting Multiple Sclerosis (RRMS) as the most common type. The aim of this study was to determine the levels of Neurofilament Light Chain (NFL) and Orexin-A (OXA) in patients with RRMS and compare it with healthy control subjects' data. In this case-control study of 61 subjects, serum and cerebrospinal fluid samples were collected from 23 RRMS patients and 38 healthy control subjects. NFL and OXA levels were determined in cerebrospinal fluid and serum samples using enzyme-linked immunosorbent assay kits. Self-reported questionnaires were also administered to evaluate fatigue severity and impact. Receiver operating characteristic curve analysis was used to determine the optimal cut-off value of NFL and OXA. The NFL and OXA concentrations in cerebro-spinal fluid of RRMS patients were significantly higher than those of the control group (p < 0.001), but no sig-nificant difference was found in the serum concentrations (p = 0.842, p = 0.597, respectively). The cut-off values were found to be 1.194 ng/ml for NFL and 77.81 pg/ml for OXA in cerebrospinal fluid. A positive correlation was found between the Expanded Disability Status Scale and Epworth Sleepiness Scale in RRMS patients (ρ = 0.49, p = 0.045). These results suggest that increased levels of both NFL and OXA in cerebrospinal fluid reflect neuronal destruction in RRMS. Further research of neurodegeneration should focus on neuropeptides to determine the possible roles in RRMS pathogenesis.