Do Intracerebral Cytokine Responses Explain the Harmful Effects of Dexamethasone in Human Immunodeficiency Virus-associated Cryptococcal Meningitis?

BACKGROUND: The CryptoDex trial showed that dexamethasone caused poorer clinical outcomes and slowed fungal clearance in human immunodeficiency virus-associated cryptococcal meningitis. We analyzed cerebrospinal fluid (CSF) cytokine concentrations from participants over the first week of treatment to investigate mechanisms of harm and test 2 hypotheses: (1) dexamethasone reduced proinflammatory cytokine concentrations, leading to poorer outcomes and (2) leukotriene A4 hydrolase (LTA4H) genotype influenced the clinical impact of dexamethasone, as observed in tuberculous meningitis. METHODS: We included participants from Vietnam, Thailand, and Uganda. Using the Luminex system, we measured CSF concentrations of the following: interferon γ, tumor necrosis factor (TNF) α, granulocyte-macrophage colony-stimulating factor, monocyte chemoattractant 1, macrophage inflammatory protein 1α, and interleukin 6, 12p70, 8, 4, 10, and 17. We determined the LTA4H genotype based on the promoter region single-nucleotide polymorphism rs17525495. We assessed the impact of dexamethasone on cytokine concentration dynamics and the association between cytokine concentration dynamics and fungal clearance with mixed effect models. We measured the influence of LTA4H genotype on outcomes with Cox regression models. RESULTS: Dexamethasone increased the rate TNF-α concentration's decline in (-0.13 log2pg/mL/d (95% confidence interval, -.22 to -.06 log2pg/mL/d; P = .03), which was associated with slower fungal clearance (correlation, -0.62; 95% confidence interval, -.83 to -.26). LTA4H genotype had no statistically significant impact on outcome or response to dexamethasone therapy. Better clinical outcomes were associated with higher baseline concentrations of interferon γ. CONCLUSIONS: Dexamethasone may slow fungal clearance and worsen outcomes by increasing TNF-α concentration's rate of decline.

Adipsin, MIP-1b, and IL-8 as CSF Biomarker Panels for ALS Diagnosis.

Amyotrophic lateral sclerosis (ALS) is an aggressive neurodegenerative disorder that selectively attacks motor neurons in the brain and spinal cord. Despite important advances in the knowledge of the etiology and progression of the disease, there are still no solid grounds in which a clinician could make an early objective and reliable diagnosis from which patients could benefit. Diagnosis is difficult and basically made by clinical rating scales (ALSRs and El Escorial). The possible finding of biomarkers to aid in the early diagnosis and rate of disease progression could serve for future innovative therapeutic approaches. Recently, it has been suggested that ALS has an important immune component that could represent either the cause or the consequence of the disease. In this report, we analyzed 19 different cytokines and growth factors in the cerebrospinal fluid of 77 ALS patients and 13 controls by decision tree and PanelomiX program. Results showed an increase of Adipsin, MIP-1b, and IL-6, associated with a decrease of IL-8 thresholds, related with ALS patients. This biomarker panel analysis could represent an important aid for diagnosis of ALS alongside the clinical and neurophysiological criteria.

Cerebrospinal Fluid NLRP3 is Increased After Severe Traumatic Brain Injury in Infants and Children.

BACKGROUND: Inflammasome-mediated neuroinflammation may cause secondary injury following traumatic brain injury (TBI) in children. The pattern recognition receptors NACHT domain-, Leucine-rich repeat-, and PYD-containing Protein 1 (NLRP1) and NLRP3 are essential components of their respective inflammasome complexes. We sought to investigate whether NLRP1 and/or NLRP3 abundance is altered in children with severe TBI. METHODS: Cerebrospinal fluid (CSF) from children (n = 34) with severe TBI (Glasgow coma scale score [GCS] ≤8) who had externalized ventricular drains (EVD) placed for routine care was evaluated for NLRP1 and NLRP3 at 0-24, 25-48, 49-72, and >72 h post-TBI and was compared to infection-free controls that underwent lumbar puncture to rule out CNS infection (n = 8). Patient age, sex, initial GCS, mechanism of injury, treatment with therapeutic hypothermia, and 6-month Glasgow outcome score were collected. RESULTS: CSF NLRP1 was undetectable in controls and detected in 2 TBI patients at only <24 h post-TBI. CSF NLRP3 levels were increased in TBI patients compared with controls at all time points, p < 0.001. TBI patients ≤4 years of age had higher peak NLRP3 levels versus patients >4 (15.50 [3.65-25.71] vs. 3.04 [1.52-8.87] ng/mL, respectively; p = 0.048). Controlling for initial GCS in multivariate analysis, peak NLRP3 >6.63 ng/mL was independently associated with poor outcome at 6 months. CONCLUSIONS: In the first report of NLRP1 and NLRP3 in childhood neurotrauma, we found that CSF NLRP3 is elevated in children with severe TBI and independently associated with younger age and poor outcome. Future studies correlating NLRP3 with other markers of inflammation and response to therapy are warranted.

Elevated cerebral spinal fluid biomarkers in children with mucopolysaccharidosis I-H.

Mucopolysaccharidosis (MPS) type-IH is a lysosomal storage disease that results from mutations in the IDUA gene causing the accumulation of glycosaminoglycans (GAGs). Historically, children with the severe phenotype, MPS-IH (Hurler syndrome) develop progressive neurodegeneration with death in the first decade due to cardio-pulmonary complications. New data suggest that inflammation may play a role in MPS pathophysiology. To date there is almost no information on the pathophysiologic changes within the cerebral spinal fluid (CSF) of these patients. We evaluated the CSF of 25 consecutive patients with MPS-IH. While CSF glucose and total protein were within the normal range, we found a significantly mean elevated CSF opening pressure at 24 cm H2O (range 14-37 cm H2O). We observed a 3-fold elevation in CSF heparan sulfate and a 3-8 fold increase in MPS-IH specific non-reducing ends, I0S0 and I0S6. Cytokine analyses in CSF of children with MPS-IH showed significantly elevated inflammatory markers including: MCP-1 SDF-1a, IL-Ra, MIP-1b, IL-8, and VEGF in comparison to unaffected children. This is the largest report of CSF characteristics in children with MPS-IH. Identification of key biomarkers may provide further insight into the inflammatory-mediated mechanisms related to MPS diseases and perhaps lead to improved targeted therapies.

Label-Free LC-MS/MS Proteomic Analysis of Cerebrospinal Fluid Identifies Protein/Pathway Alterations and Candidate Biomarkers for Amyotrophic Lateral Sclerosis.

Analysis of the cerebrospinal fluid (CSF) proteome has proven valuable to the study of neurodegenerative disorders. To identify new protein/pathway alterations and candidate biomarkers for amyotrophic lateral sclerosis (ALS), we performed comparative proteomic profiling of CSF from sporadic ALS (sALS), healthy control (HC), and other neurological disease (OND) subjects using label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 1712 CSF proteins were detected and relatively quantified by spectral counting. Levels of several proteins with diverse biological functions were significantly altered in sALS samples. Enrichment analysis was used to link these alterations to biological pathways, which were predominantly related to inflammation, neuronal activity, and extracellular matrix regulation. We then used our CSF proteomic profiles to create a support vector machines classifier capable of discriminating training set ALS from non-ALS (HC and OND) samples. Four classifier proteins, WD repeat-containing protein 63, amyloid-like protein 1, SPARC-like protein 1, and cell adhesion molecule 3, were identified by feature selection and externally validated. The resultant classifier distinguished ALS from non-ALS samples with 83% sensitivity and 100% specificity in an independent test set. Collectively, our results illustrate the utility of CSF proteomic profiling for identifying ALS protein/pathway alterations and candidate disease biomarkers.

Changes in PINCH levels in the CSF of HIV+ individuals correlate with hpTau and CD4 count.

Several studies report associations between the particularly interesting new cysteine histidine-rich (PINCH) protein and HIV-associated CNS disease. PINCH is detected in the CSF of HIV patients, and changes in levels during disease may be indicative of changes in disease status over time. PINCH binds hyperphosphorylated Tau (hpTau) in the brain and CSF, but little is known about the relevance of these interactions to HIV CNS disease. In this study, PINCH and hpTau levels were assessed in three separate CSF samples collected longitudinally from 20 HIV+ participants before and after initiating antiretroviral therapy or before and after a change in the treatment regimen. The intervals were approximately 1 (T2) and 3-7 (T3) months from the initial visit (baseline, T1). Correlational analyses were conducted for CSF levels of PINCH and hpTau and other variables including blood CD4 T-cell count, plasma and CSF viral burden, CSF neopterin, white blood cell (WBC) count, and antiretroviral CNS penetration effectiveness (CPE). Values for PINCH and hpTau were determined for each patient by calculating the fold changes between the second (T2) and third measurements (T3) from the baseline measurement (T1). Statistical analyses showed that the fold changes in CSF PINCH protein from T1 to T2 were significantly higher in participants with CD4 counts >200 cells/mm(3) at T2 compared to those with CD4 counts <200 cells/mm(3) at T2. This trend persisted irrespective of plasma or CSF viral burden or antiretroviral therapy CPE scores. The fold changes in PINCH levels between T1 and T2, and T1 and T3 were highly correlated to the fold changes in hpTau at T2/T1 and T3/T1 (correlation coefficient = 0.69, p < 0.001; correlation coefficient = 0.83, p < 0.0001, respectively). In conclusion, in these HIV participants, changes in CSF levels of PINCH appear to correlate with changes in blood CD4 count and with changes in CSF hpTau levels, but not with plasma or CSF viral burden, neopterin, WBC, or antiretroviral regimen CPE.

Inflammasome proteins in cerebrospinal fluid of brain-injured patients as biomarkers of functional outcome: clinical article.

OBJECT: Traumatic brain injury (TBI), the third most common CNS pathology, plagues 5.3 million Americans with permanent TBI-related disabilities. To evaluate injury severity and prognosis, physicians rely on clinical variables. Here, the authors seek objective, biochemical markers reflecting molecular injury mechanisms specific to the CNS as more accurate measurements of injury severity and outcome. One such secondary injury mechanism, the innate immune response, is regulated by the inflammasome, a molecular platform that activates caspase-1 and interleukin-1ß. METHODS: The authors investigated whether inflammasome components were present in the CSF of 23 patients with TBI and whether levels of inflammasome components correlate with outcome. The authors performed an immunoblot analysis of CSF samples from patients who suffered TBI and nontrauma controls and assessed the outcomes 5 months postinjury by using the Glasgow Outcome Scale. Data were analyzed using Mann-Whitney U-tests and linear regression analysis. RESULTS: Patients with severe or moderate cranial trauma exhibited significantly higher CSF levels of the inflammasome proteins ASC, caspase-1, and NALP-1 than nontrauma controls (p < 0.0001, p = 0.0029, and p = 0.0202, respectively). Expression of each protein correlated significantly with the Glasgow Outcome Scale score at 5 months postinjury (p < 0.05). ASC, caspase-1, and NALP-1 were significantly higher in the CSF of patients with unfavorable outcomes, including death and severe disability (p < 0.0001). CONCLUSIONS: NALP-1 inflammasome proteins are potential biomarkers to assess TBI severity, outcome, and the secondary injury mechanisms impeding recovery, serving as adjuncts to clinical predictors.

BCL10 single nucleotide polymorphism and its association with CSF dissemination of primary intracranial germ cell tumors.

BACKGROUND: Intracranial germ cell tumors (GCTs) are rare neoplasms. Little is known about the pathogenesis of these tumors. The BCL10 gene, a proapoptotic signaling molecule involved in the Apaf-1/caspase-9 cell death pathway, may act as a tumor suppressor gene in multiple types of tumors including testicular GCTs. METHODS: To evaluate whether alterations in the BCL10 gene play a role in the genesis of intracranial GCTs, we analyzed the BCL10 gene in 10 pure germinomas (PGs) and 10 nongerminomatous GCTs. RESULTS: We found no inactivating mutations; however, 5 of 10 PGs and 1 of 10 nongerminomatous GCTs manifested specific single nucleotide polymorphisms (SNPs) that carried an amino acid substitution at codon 5 in exon 1 or codon 162 in exon 3. This SNP occurs at higher frequency in patients with PGs than healthy individuals (p = 0.07). CSF dissemination occurred in 4 of our 6 patients manifesting SNP (p = 0.037). CONCLUSIONS: Our data suggest that this specific SNP in the BCL10 gene may be partly responsible for the tumorigenesis of PG in Japanese individuals, and may be associated with the aggressive nature of these tumors.