Rapid and ultrasensitive detection of acute kidney injury biomarkers CH3L1 and L-FABP using surface-enhanced Raman spectroscopy.

Chitinase 3-like 1 (CH3L1) and liver fatty acid binding protein (L-FABP) are promising biomarkers for the early diagnosis of acute kidney injury (AKI). Here, a highly sensitive method for the quantitative detection of CH3L1 and L-FABP by surface-enhanced Raman spectroscopy (SERS) based on graphene oxide/gold and silver core-shell nanoparticles (GO/Au@Ag NPs) was proposed. The results showed that such GO/Au@Ag substrate can achieve rapid sensing of CH3L1 and L-FABP with a wide response range (2 × 10-1 to 2 × 10-8 mg/mL and 1.2 × 10-1 to 1.2 × 10-8 mg/mL, respectively) and high sensitivity. The detection limits of CH3L1 and L-FABP were 1.21 × 10-8 mg/mL and 0.62 × 10-8 mg/mL, respectively. In addition, the simultaneous detection of the two biomarkers in serum was demonstrated, showing the feasibility of this method in the complex biological environment. The detection of CH3L1 and L-FABP will greatly improve the early diagnosis and intervention of AKI.

Tear-Derived Exosome Proteins Are Increased in Patients with Thyroid Eye Disease.

Exosomes contain proteins, lipids, RNA, and DNA that mediate intercellular signaling. Exosomes can contribute to the pathological processes of various diseases, although their roles in ocular diseases are unclear. We aimed to isolate exosomes from tear fluids (TF) of patients with Thyroid eye disease (TED) and analyze the exosomal proteins. TFs were collected from eight patients with TED and eight control subjects. The number of TF exosomes were measured using nanoparticle-tracking analysis. The expression of specific proteins in the purified exosome pellets were analyzed using a Proteome Profiler Array Kit. Cultured normal orbital fibroblasts were incubated with TF exosomes from patients with TED and control subjects, and changes in inflammatory cytokine levels were compared. TF exosomes from TED patients showed more exosomes than the control subjects. The expression levels of exosomal proteins vitamin D-binding (VDB) protein, C-reactive protein (CRP), chitinase 3-like 1 (CHI3L1), matrix metalloproteinase-9 (MMP-9), and vascular adhesion molecule-1 (VCAM-1) were significantly increased in patients with TED, compared to those of controls. Orbital fibroblasts exposed to TF exosomes from patients with TED showed significantly higher levels of interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 (MCP-1) production than those treated with control TF exosomes. Specific proteins showed higher expression in exosomes from TED patients, implying that they may play keys roles in TED pathogenesis.

A blood-based biomarker panel (NIS4) for non-invasive diagnosis of non-alcoholic steatohepatitis and liver fibrosis: a prospective derivation and global validation study.

BACKGROUND: Non-invasive tests that can identify patients with non-alcoholic steatohepatitis (NASH) at higher risk of disease progression are lacking. We report the development and validation of a blood-based diagnostic test to non-invasively rule in and rule out at-risk NASH (defined as non-alcoholic fatty liver disease [NAFLD] activity score [NAS] ≥4 and fibrosis stage ≥2). METHODS: In this prospective derivation and global validation study, blood samples, clinical data, and liver biopsy results from three independent cohorts with suspected NAFLD were used to develop and validate a non-invasive blood-based diagnostic test, called NIS4. Derivation was done in the discovery cohort, which comprised 239 prospectively recruited patients with biopsy-confirmed NASH (NAFLD NAS ≥3; fibrosis stage 0-3) from the international GOLDEN-505 phase 2b clinical trial. A complete matrix based on 23 variables selected for univariate association with the presence of at-risk NASH and avoiding high multi-collinearity was used to derive the model in a bootstrap-based process that minimised the Akaike information criterion. The overall diagnostic performance of NIS4 was externally validated in two independent cohorts: RESOLVE-IT diag and Angers. The RESOLVE-IT diag cohort comprised the first 475 patients screened for potential inclusion into the RESOLVE-IT phase 3 clinical trial. Angers was a retrospective cohort of 227 prospectively recruited patients with suspected NAFLD and clinical risk factors for NASH or fibrosis stage 2 or more according to abnormal elastography results or abnormal liver biochemistry. Both external validation cohorts were independently analysed and were combined into a pooled validation cohort (n=702) to assess clinical performance of NIS4 and other non-invasive tests. FINDINGS: The derived NIS4 algorithm comprised four independent NASH-associated biomarkers (miR-34a-5p, alpha-2 macroglobulin, YKL-40, and glycated haemoglobin; area under the receiver operating characteristics curve [AUROC] 0·80, 95% CI 0·73-0·85), and did not require adjustment for age, sex, body-mass index (BMI), or aminotransferase concentrations. Clinical cutoffs were established within the discovery cohort to optimise both rule out and rule in clinical performance while minimising indeterminate results. NIS4 was validated in the RESOLVE-IT diag cohort (AUROC 0·83, 95% CI 0·79-0·86) and the Angers cohort (0·76, 0·69-0·82). In the pooled validation cohort, patients with a NIS4 value less than 0·36 were classified as not having at-risk NASH (ruled out) with 81·5% (95% CI 76·9-85·3) sensitivity, 63·0% (57·8-68·0) specificity, and a negative predictive value of 77·9% (72·5-82·4), whereas those with a NIS4 value of more than 0·63 were classified as having at-risk NASH (ruled in) with 87·1% (83·1-90·3) specificity, 50·7% (45·3-56·1) sensitivity, and a positive predictive value of 79·2% (73·1-84·2). The diagnostic performance of NIS4 within the external validation cohorts was not influenced by age, sex, BMI, or aminotransferase concentrations. INTERPRETATION: NIS4 is a novel blood-based diagnostic that provides an effective way to non-invasively rule in or rule out at-risk NASH in patients with metabolic risk factors and suspected disease. Use of NIS4 in clinical trials or in the clinic has the potential to greatly reduce unnecessary liver biopsies in patients with lower risk of disease progression. FUNDING: Genfit.

The expression levels of CHI3L1 and IL15Rα correlate with TGM2 in duodenum biopsies of patients with celiac disease.

OBJECTIVE AND DESIGN: Celiac disease (CD) is an intestinal inflammatory disorder of the small intestine. Gliadins are a component of gluten and there are three main types (α, γ, and ω). Recent studies indicate that gliadin peptides are able to activate an innate immune response. IL15 is a major mediator of the innate immune response and is involved in the early alteration of CD mucosa. The chitinase molecules are highly expressed by the innate immune cells during the inflammatory processes. MATERIAL OR SUBJECTS: We analyzed several microarray datasets of PBMCs and duodenum biopsies of CD patients and healthy control subjects (HCs). We verified the modulation CHI3L1 in CD patients and correlated the expression levels to the IL15, IL15Rα, TGM2, IFNγ, and IFNGR1/2. Duodenal biopsy samples belonged to nine active and nine treated children patients (long-term effects of gliadin), and 17 adult CD patients and 10 adults HCs. We also selected 169 samples of PBMCs from 127 CD patients on adherence to a gluten-free diet (GFD) for at least 2 years and 44 HCs. RESULTS: Our analysis showed that CHI3L1 and IL15Rα were significantly upregulated in adult and children's celiac duodenum biopsies. In addition, the two genes were correlated significantly both in children than in adults CD duodenum biopsies. No significant modulation was observed in PBMCs of adult CD patients compared to the HCs. The correlation analysis of the expression levels of CHI3L1 and IL15Rα compared to TGM showed significant values both in adults and in children duodenal biopsies. Furthermore, the IFNγ expression levels were positively correlated with CHI3L1 and IL15Rα. Receiver operating characteristic (ROC) analysis confirmed the diagnostic ability of CHI3L1 and IL15Rα to discriminate CD from HCs. CONCLUSION: Our data suggest a role for CHI3L1 underlying the pathophysiology of CD and represent a starting point aiming to inspire new investigation that proves the possible use of CHI3L1 as a diagnostic factor and therapeutic target.

Frontal cortex chitinase and pentraxin neuroinflammatory alterations during the progression of Alzheimer's disease.

BACKGROUND: Chitinase 3-like 1 (CHI3L1), chitinase 3-like 2 (CHI3L2), and neuronal pentraxin II (NPTX2) are inflammatory biomarkers of Alzheimer's disease (AD). Although studies have demonstrated that cerebrospinal fluid levels of these proteins are changed in AD, no studies have undertaken a detailed examination of alterations in protein levels, cellular expression, and interaction with amyloid in the brain during the progression of AD. METHODS: The study evaluated levels of both CHI3L1 and CHI3L2, NPTX2, ionized calcium-binding adapter molecule 1 (Iba1), complement component 1q (C1q), glial fibrillary acidic protein (GFAP), and CD44, in the frontal cortex of people who died with an antemortem clinical diagnosis of no cognitive impairment (NCI), mild cognitive impairment (MCI), mild/moderate AD (mAD), and severe AD (sAD) using immunoblot and immunohistochemical techniques. RESULTS: CHI3L1-immunoreactive (-ir) astrocyte numbers were increased in the frontal cortex and white matter in sAD compared to NCI. On the other hand, increases in GFAP and Iba1-ir cell numbers were observed in MCI compared to NCI but only in white matter. Western blot analyses revealed significantly lower frontal cortex CHI3L2 levels, whereas CD44 levels were increased in sAD. No significant differences for CHI3L1, GFAP, C1q, and NPTX2 protein levels were detected between clinical groups. Strong significant correlations were found between frontal cortex CHI3L1 and Iba1-ir cell numbers in white matter and CHI3L1 and C1q protein levels in the early stages of the disease. C1q and Iba1, CD44 with CHI3L2, and GFAP protein levels were associated during disease progression. CHI3L1 and Iba1 cell numbers in white matter showed a significant associations with episodic memory and perceptual speed. CONCLUSIONS: White matter CHI3L1 inflammatory response is associated with cognitive impairment early in the onset of AD.

Measured and genetically predicted plasma YKL-40 levels and melanoma mortality.

PURPOSE: High plasma levels of YKL-40 might be associated with mortality in patients with melanoma, and it is unknown if YKL-40 is causally related to mortality. EXPERIMENTAL DESIGN: We studied two cohorts: 2618 patients with melanoma from hospital clinics and 1413 general population patients with melanoma, totalling 4031 patients followed up for mortality end-points for up to 20 years. All were genotyped for CHI3L1 rs4950928, highly predictive of lifelong plasma YKL-40, and plasma YKL-40 levels were measured in 2165 patients. We tested the hypotheses that measured and genetically predicted high plasma YKL-40 are associated with increased mortality in patients with melanoma. RESULTS: For the hospital melanoma cohort, age- and sex-adjusted hazard ratios for death in individuals with measured plasma YKL-40 in the 96-100th percentile versus 1-95th percentile and per 10-percentile increase were 1.52 (95% confidence interval, 1.07-2.16) and 1.07 (1.02-1.11), respectively, most pronounced for patients with localised melanomas. Each C-allele of the CHI3L1 rs4950928 genotype was associated with plasma YKL-40 level increases of 32% in the hospital melanoma cohort (p = 6 × 10-48) and 43% in the general population melanoma cohort (p = 7 × 10-13). Multifactorially adjusted ratios for these increases in the combined cohorts were 1.04 (1.00-1.09) observationally for measured plasma YKL-40 and 0.98 (0.86-1.12) for the genetically predicted plasma YKL-40. CONCLUSION: Measured, but not genetically predicted, increasing plasma YKL-40 was associated with increased mortality in patients with melanoma. Plasma YKL-40 is a marker but less likely to be a cause of increased mortality in patients with melanoma.

Glycoprotein YKL-40 Is Elevated and Predicts Disease Severity in Puumala Hantavirus Infection.

Most cases of hemorrhagic fever with renal syndrome (HFRS) in Europe are caused by the Puumala hantavirus (PUUV). Typical features of the disease are increased vascular permeability, acute kidney injury (AKI), and thrombocytopenia. YKL-40 is an inflammatory glycoprotein involved in various forms of acute and chronic inflammation. In the present study, we examined plasma YKL-40 levels and the associations of YKL-40 with disease severity in acute PUUV infection. A total of 79 patients treated in Tampere University Hospital during 2005-2014 were studied. Plasma YKL-40 was measured in the acute phase, the recovery phase, and one year after hospitalization. Plasma YKL-40 levels were higher during the acute phase compared to the recovery phase and one year after hospitalization (median YKL-40 142 ng/mL, range 11-3320, vs. 45 ng/mL, range 15-529, vs. 32 ng/mL, range 3-213, p < 0.001). YKL-40 level was correlated with the length of hospital stay (r = 0.229, p = 0.042), the levels of inflammatory markers-that is, blood leukocytes (r = 0.234, p = 0.040), plasma C-reactive protein (r = 0.332, p = 0.003), and interleukin-6 (r = 0.544, p < 0.001), and maximum plasma creatinine level (r = 0.370, p = 0.001). In conclusion, plasma YKL-40 levels were found to be elevated during acute PUUV infection and correlated with the overall severity of the disease, as well as with the degree of inflammation and the severity of AKI.

Concentration of Chondrogenic Soluble Factors in Freshly Harvested Lipoaspirate.

BACKGROUND: Cartilage tissue has a limited capacity for healing with the consequence that patients are often treated symptomatically until they become candidates for osteotomy or total joint replacement. Alternative biological therapies, for example, application of platelet-rich plasma and implantation of chondrocytes and mesenchymal stem cells, have emerged as a new treatment modality to repair articular cartilage. In addition, autologous fat transfer is performed for treatment of cartilage defects, example given, in osteoarthrosis, but several questions regarding basic biochemical properties of the transplant remain unanswered. Bone morphogenetic protein 4 (BMP4), matrix metalloproteinase (MMP)-8, cartilage oligomeric matrix protein (COMP), and chitinase-3-like protein 1 (CHI3L1) have been shown to be involved in chondrogenic regeneration and represent potential therapeutic agents for cartilage repair. However, no study regarding naturally occurring levels of these soluble factors in transplanted adipose tissue has yet been performed. METHODS: To investigate the influence of age, body mass index, donor site, and sex on the concentration of BMP4, MMP-8, COMP, and CHI3L1 in freshly aspirated adipose tissue, their content was measured by means of enzyme-linked immunosorbent assay readings. RESULTS: There were significant quantities of BMP4, MMP-8, COMP, and CHI3L1 (23.6, 249.9, 298.0, and 540.6 pg/mg, respectively) in the lipoaspirate harvested for transplantation. There was no correlation between the content of soluble factors and the patients' age or body mass index. Furthermore, the sex did not affect the amount of the investigated factors. However, there were significantly lower contents of BMP4, COMP, and CHI3L1 found in lipoaspirates harvested from the abdomen compared with nonabdominal donor sites. CONCLUSIONS: Naturally occurring differences in the concentrations of the investigated soluble factors will favor certain donor sites for autologous fat transfer in the field of cartilage repair. Thus, increasing knowledge will enable researchers and clinicians to make autologous fat transfer procedures more reliable and efficient for treatment of articular cartilage defects.

Chitinase 3-like 1 protein plays a critical role in respiratory syncytial virus-induced airway inflammation.

BACKGROUND: Chitinase 3-like 1 protein (CHI3L1) (YKL-40 in humans and breast regression protein [BRP]-39 in mice) is required for optimal allergen sensitization and Th2 inflammation in various chronic inflammatory diseases including asthma. However, the role of CHI3L1 in airway inflammation induced by respiratory viruses has not been investigated. The aim of this study was to investigate the relationship between CHI3L1 and airway inflammation caused by respiratory syncytial virus (RSV) infection. METHODS: We measured YKL-40 levels in human nasopharyngeal aspirate (NPA) from hospitalized children presenting with acute respiratory symptoms. Wild-type (WT) and BRP-39 knockout (KO) C57BL/6 mice were inoculated with live RSV (A2 strain). Bronchoalveolar lavage fluid and lung tissue samples were obtained on day 7 after inoculation to assess lung inflammation, airway reactivity, and expression of cytokines and BRP-39. RESULTS: In human subjects, YKL-40 and IL-13 levels in NPA were higher in children with RSV infection than in control subjects. Expression of BRP-39 and Th2 cytokines, IL-13 in particular, was increased following RSV infection in mice. Airway inflammation caused by RSV infection was reduced in BRP-39 KO mice as compared to WT mice. Th2 cytokine levels were not increased in the lungs of RSV-infected BRP-39 KO mice. BRP-39 regulated M2 macrophage activation in RSV-infected mice. Additionally, treatment with anti-CHI3L1 antibody attenuated airway inflammation and Th2 cytokine production in RSV-infected WT mice. CONCLUSION: These findings suggest that CHI3L1 could contribute to airway inflammation induced by RSV infection. CHI3L1 could be a potential therapeutic candidate for attenuating Th2-associated immunopathology during RSV infection.

YKL-40 levels are associated with disease severity and prognosis of viral pneumonia, but not available in bacterial pneumonia in children.

BACKGROUND: Viral pneumonia is the main type of community-acquired pneumonia (CAP) in children. YKL-40, a chitinase-like protein, is regarded as a biomarker of the degree of inflammation. METHODS: Children who were diagnosed with CAP, including viral pneumonia, bacterial pneumonia, and dual infection, were included in the cohort study. The pathogenic diagnosis depended on PCR and immunoassay test. YKL-40 levels were examined twice by enzyme-linked immunoassay (ELISA). RESULTS: Serum YKL-40 levels were higher in patients with pneumonia than in healthy controls. The admission levels of YKL-40 in serum and Bronchoalveolar lavage (BALFs) indicated a positive correlation with the serum levels of C-reactive protein and other inflammatory cytokines (IL-6 and TNF-α). The disease severity have no correlation with the admission serum levels of YKL-40. Meanwhile, reductions in YKL-40 levels from initial admission levels to day 5 post-admission were correlated with disease severity. The multiple logistic analysis indicated the decreased extent of serum YKL-40 level as an independent prognostic predictor of severe cases in patients with viral pneumonia. CONCLUSIONS: Reductions in serum YKL-40 levels on day 5 after receiving therapy is a possible prognostic biomarker for children with viral pneumonia.

YKL-40 in the brain and cerebrospinal fluid of neurodegenerative dementias.

BACKGROUND: YKL-40 (also known as Chitinase 3-like 1) is a glycoprotein produced by inflammatory, cancer and stem cells. Its physiological role is not completely understood but YKL-40 is elevated in the brain and cerebrospinal fluid (CSF) in several neurological and neurodegenerative diseases associated with inflammatory processes. Yet the precise characterization of YKL-40 in dementia cases is missing. METHODS: In the present study, we comparatively analysed YKL-40 levels in the brain and CSF samples from neurodegenerative dementias of different aetiologies characterized by the presence of cortical pathology and disease-specific neuroinflammatory signatures. RESULTS: YKL-40 was normally expressed in fibrillar astrocytes in the white matter. Additionally YKL-40 was highly and widely expressed in reactive protoplasmic cortical and perivascular astrocytes, and fibrillar astrocytes in sporadic Creutzfeldt-Jakob disease (sCJD). Elevated YKL-40 levels were also detected in Alzheimer's disease (AD) but not in dementia with Lewy bodies (DLB). In AD, YKL-40-positive astrocytes were commonly found in clusters, often around ß-amyloid plaques, and surrounding vessels with ß-amyloid angiopathy; they were also distributed randomly in the cerebral cortex and white matter. YKL-40 overexpression appeared as a pre-clinical event as demonstrated in experimental models of prion diseases and AD pathology. CSF YKL-40 levels were measured in a cohort of 288 individuals, including neurological controls (NC) and patients diagnosed with different types of dementia. Compared to NC, increased YKL-40 levels were detected in sCJD (p < 0.001, AUC = 0.92) and AD (p < 0.001, AUC = 0.77) but not in vascular dementia (VaD) (p > 0.05, AUC = 0.71) or in DLB/Parkinson's disease dementia (PDD) (p > 0.05, AUC = 0.70). Further, two independent patient cohorts were used to validate the increased CSF YKL-40 levels in sCJD. Additionally, increased YKL-40 levels were found in genetic prion diseases associated with the PRNP-D178N (Fatal Familial Insomnia) and PRNP-E200K mutations. CONCLUSIONS: Our results unequivocally demonstrate that in neurodegenerative dementias, YKL-40 is a disease-specific marker of neuroinflammation showing its highest levels in prion diseases. Therefore, YKL-40 quantification might have a potential for application in the evaluation of therapeutic intervention in dementias with a neuroinflammatory component.

Characterisation of asthma subgroups associated with circulating YKL-40 levels.

The chitinase-like protein YKL-40 mediates airway inflammation and serum levels are associated with asthma severity. However, asthma phenotypes associated with YKL-40 levels have not been precisely defined.We conducted an unsupervised cluster analysis of asthma patients treated at the Yale Center for Asthma and Airways Disease (n=156) to identify subgroups according to YKL-40 level. The resulting YKL-40 clusters were cross-validated in cohorts from the Severe Asthma Research Programme (n=167) and the New York University/Bellevue Asthma Repository (n=341). A sputum transcriptome analysis revealed molecular pathways associated with YKL-40 subgroups.Four YKL-40 clusters (C1-C4) were identified. C3 and C4 had high serum YKL-40 levels compared with C1 and C2. C3 was associated with earlier onset and longer duration of disease, severe airflow obstruction, and near-fatal asthma exacerbations. C4 had the highest serum YKL-40 levels, adult onset and less airflow obstruction, but frequent exacerbations. An airway transcriptome analysis in C3 and C4 showed activation of non-type 2 inflammatory pathways.Elevated serum YKL-40 levels were associated with two distinct clinical asthma phenotypes: one with irreversible airway obstruction and another with severe exacerbations. The YKL-40 clusters are potentially useful for identification of individuals with severe or exacerbation-prone asthma.

Correlation between molecular features and genetic subtypes of Glioblastoma: critical analysis in 109 cases / Correlação entre as características moleculares e os subtipos genéticos dos glioblastomas: análise crítica de 109 casos

OBJECTIVE: Glioblastoma, the most common and lethal brain tumor, is also one of the most defying forms of malignancies in terms of treatment. Integrated genomic analysis has searched deeper into the molecular architecture of GBM, revealing a new sub-classification and promising precision in the care for patients with specific alterations. METHOD: Here, we present the classification of a Brazilian glioblastoma cohort into its main molecular subtypes. Using a high-throughput DNA sequencing procedure, we have classified this cohort into proneural, classical and mesenchymal sub-types. Next, we tested the possible use of the overexpression of the EGFR and CHI3L1 genes, detected through immunohistochemistry, for the identification of the classical and mesenchymal subtypes, respectively. RESULTS: Our results demonstrate that genetic identification of the glioblastoma subtypes is not possible using single targeted mutations alone, particularly in the case of the Mesenchymal subtype. We also show that it is not possible to single out the mesenchymal cases through CHI3L1 expression. CONCLUSION: Our data indicate that the Mesenchymal subtype, the most malignant of the glioblastomas, needs further and more thorough research to be ensure adequate identification.

OBJETIVO: O glioblastoma (GBM), o tumor cerebral mais comum e mais letal, é também um dos tipos de tumores de mais difícil tratamento. Análises genômicas integradas têm contribuído para um melhor entendimento da arquitetura molecular dos GBMs, revelando uma nova subclassificação com a promessa de precisão no tratamento de pacientes com alterações específicas. Neste estudo, nós apresentamos a classificação de uma casuística brasileira de GBMs dentro dos principais subtipos do tumor. MÉTODO: Usando sequenciamento de DNA em larga escala, foi possível classificar os tumores em proneural, clássico e mesenquimal. Em seguida, testamos o possível uso da hiperexpressão de EGFR e CHI3L1 para a identificação dos subtipos clássico e mesenquimal, respectivamente. RESULTADOS: Nossos resultados deixam claro que a identificação genética dos subtipos moleculares de GBM não é possível utilizando-se apenas um único tipo de mutação, em particular nos casos de GBMs mesenquimais. Da mesma forma, não é possível distinguir os casos mesenquimais apenas com a expressão de CHI3L1. CONCLUSÃO: Nossos dados indicam que o subtipo mesenquimal, o mais maligno dos GBMs, necessita de uma análise mais aprofundada para sua identificação.

Serum YKL-40 is a reliable biomarker for pulmonary alveolar proteinosis.

BACKGROUND AND OBJECTIVE: Pulmonary alveolar proteinosis (PAP) is a rare disease characterized by alveolar filling. YKL-40, a chitinase-like protein produced by macrophages and epithelial cells, is increased in patients with interstitial lung diseases. We aimed to evaluate the role of YKL-40 as a biomarker for PAP. METHODS: A total of 34 patients with autoimmune PAP and 50 healthy controls were studied. YKL-40 was measured by ELISA in serum and bronchoalveolar lavage fluid (BALF). Chitinase coding gene polymorphisms (CHI3L1-329 and -131) were detected by PCR and pyrosequencing. Correlations between serum YKL-40 levels and disease outcome were analysed. RESULTS: Baseline serum and BALF levels of YKL-40 were higher in PAP patients than in controls (286 ± 27 ng/mL vs 42 ± 4 ng/mL, P < 0.0001; 323 ± 36 ng/mL vs 3 ± 1 ng/mL, P < 0.0001, respectively). Serum YKL-40 levels correlated with diffusing capacity of the lung for carbon monoxide (DLCO ) at baseline (P = 0.002) and over time (P < 0.0001). Patients with disease progression had higher baseline serum YKL-40 levels than those who remained stable or improved (P < 0.0001). A baseline cut-off level of 300 ng/mL was predictive of disease progression (HR (hazard ratio): 7.875, P = 0.001). The presence of the G allele was associated with higher serum and BALF levels of YKL-40. CONCLUSION: YKL-40 is elevated in serum and BALF of PAP patients, and may be of clinical utility to predict outcome in PAP.

Markers of neuroinflammation and neuronal injury in bipolar disorder: Relation to prospective clinical outcomes.

Neuroimmune mechanisms have been linked to the pathophysiology of bipolar disorder based on studies of biomarkers in plasma, cerebrospinal fluid (CSF), and postmortem brain tissue. There are, however, no longitudinal studies investigating if CSF markers of neuroinflammation and neuronal injury predict clinical outcomes in patients with bipolar disorder. We have in previous studies found higher CSF concentrations of interleukin-8 (IL-8), monocyte chemoattractant protein 1 (MCP-1/CCL-2), chitinase-3-like protein 1 (CHI3L1/YKL-40), and neurofilament light chain (NF-L) in euthymic patients with bipolar disorder compared with controls. Here, we investigated the relationship of these CSF markers of neuroinflammation and neuronal injury with clinical outcomes in a prospective study. 77 patients with CSF analyzed at baseline were followed for 6-7years. Associations of baseline biomarkers with clinical outcomes (manic/hypomanic and depressive episodes, suicide attempts, psychotic symptoms, inpatient care, GAF score change) were investigated. Baseline MCP-1 concentrations were positively associated with manic/hypomanic episodes and inpatient care during follow-up. YKL-40 concentrations were negatively associated with manic/hypomanic episodes and with occurrence of psychotic symptoms. The prospective negative association between YKL-40 and manic/hypomanic episodes survived multiple testing correction. Concentrations of IL-8 and NF-L were not associated with clinical outcomes. High concentrations of these selected CSF markers of neuroinflammation and neuronal injury at baseline were not consistently associated with poor clinical outcomes in this prospective study. The assessed proteins may be involved in adaptive immune processes or reflect a state of vulnerability for bipolar disorder rather than being of predictive value for disease progression.

Validity of Klotho, CYR61 and YKL-40 as ideal predictive biomarkers for acute kidney injury: review study / Validade de Klotho, CYR61 e YKL-40 como biomarcadores preditivos ideais para lesão renal aguda: estudo de revisão

ABSTRACT CONTEXT AND OBJECTIVE: Acute kidney injury (AKI) is still a headache for clinicians and scientists as a possible reason for increased death among intensive care unit (ICU) patients after invasive cardiac surgery. Furthermore, the diagnostic process for AKI using conventional biomarkers is not sufficient to ensure early warning of this condition because of the morbid influence of non-renal factors that definitively delay the time for the prognosis. These imposed limitations have led to significant amounts of research targeted towards identifying novel biomarkers for AKI with a sustained degree of sensitivity and specificity. Here, we reviewed previous studies conducted on the Klotho, CYR61 and YKL-40 biomarkers in relation to AKI. DESIGN AND SETTING: Review of the literature conducted in the Institute of Clinical Chemistry & Biochemistry, Ljubljana University Medical Center, Slovenia. METHODS: The literature was searched in PubMed and the Cochrane Library. From the database of this specialty, we selected 17 references that matched our context for detailed analysis and further investigation. RESULTS: The studies reviewed showed notable differences in their results relating to the diagnostic impact of Klotho, CYR61 and YKL-40 on early prediction of AKI. CONCLUSIONS: The results regarding the Klotho, CYR61 and YKL-40 biomarkers showed markedly equivocal performance in the previous studies and did not fulfill the expectations that these factors would form valid possible biomarkers for AKI.

RESUMO CONTEXTO E OBJETIVO: A lesão renal aguda (LRA) ainda é uma dor de cabeça para os clínicos e cientistas como possível razão para o aumento da mortalidade entre os pacientes de unidade de terapia intensiva (UTI) após cirurgia cardíaca invasiva. Além disso, o processo de diagnóstico para LRA usando biomarcadores convencionais não é suficiente para garantir um alerta precoce desta condição, devido à influência mórbida de fatores não renais que podem retardar o tempo para o prognóstico. Essas limitações geraram quantidades significativas de pesquisas orientadas para identificar novos biomarcadores para LRA com um grau adequado de sensibilidade e especificidade. Revisamos estudos anteriores realizados sobre os biomarcadores Klotho, CYR61, YKL-40 para LRA. TIPO DE ESTUDO E LOCAL: Revisão da literatura realizada no Instituto de Química Clínica e Bioquímica, Centro Médico da Universidade de Ljubljana, Eslovênia. MÉTODOS: A literatura foi pesquisada no PubMed e Cochrane Library. A partir da base de dados da especialidade, selecionamos 17 referências que combinavam com o contexto para uma análise detalhada e mais investigação. RESULTADOS: Os estudos revisados mostraram diferenças notáveis nos resultados sobre o impacto diagnóstico de Klotho, CYR61 e YKL-40 sobre a detecção precoce do LRA. CONCLUSÃO: Os resultados em relação aos biomarcadores Klotho, CYR61 e YKL-40 mostraram desempenho marcadamente equívoco nos estudos anteriores e não cumpriram as expectativas de que estes fatores constituam possíveis biomarcadores válidos para LRA.

Validity of Klotho, CYR61 and YKL-40 as ideal predictive biomarkers for acute kidney injury: review study.

CONTEXT AND OBJECTIVE:: Acute kidney injury (AKI) is still a headache for clinicians and scientists as a possible reason for increased death among intensive care unit (ICU) patients after invasive cardiac surgery. Furthermore, the diagnostic process for AKI using conventional biomarkers is not sufficient to ensure early warning of this condition because of the morbid influence of non-renal factors that definitively delay the time for the prognosis. These imposed limitations have led to significant amounts of research targeted towards identifying novel biomarkers for AKI with a sustained degree of sensitivity and specificity. Here, we reviewed previous studies conducted on the Klotho, CYR61 and YKL-40 biomarkers in relation to AKI. DESIGN AND SETTING:: Review of the literature conducted in the Institute of Clinical Chemistry & Biochemistry, Ljubljana University Medical Center, Slovenia. METHODS:: The literature was searched in PubMed and the Cochrane Library. From the database of this specialty, we selected 17 references that matched our context for detailed analysis and further investigation. RESULTS:: The studies reviewed showed notable differences in their results relating to the diagnostic impact of Klotho, CYR61 and YKL-40 on early prediction of AKI. CONCLUSIONS:: The results regarding the Klotho, CYR61 and YKL-40 biomarkers showed markedly equivocal performance in the previous studies and did not fulfill the expectations that these factors would form valid possible biomarkers for AKI.

Elevated YKL-40 expression is associated with a poor prognosis in breast cancer patients.

Numerous studies have investigated the prognostic role of YKL-40 in breast cancer, but yielded inconsistent results. To derive a more precise evaluation, relevant publications assessing the association between YKL-40 expression and clinical outcome of breast cancer patients were electronically searched and identified. A combined analysis of included studies was performed using fixed- or random-effect model to calculate the pooled hazard ratio (HR) or odds ratio(OR) and 95% confidence interval (95%CI) for the assessment of the association. Ten eligible studies involving 1250 patients were ultimately included in the meta-analysis. Overall, the pooled analysis showed that elevated YKL-40 expression was significantly associated with a poor overall survival(OS: HR=1.48, 95%CI= 1.11-1.97) and disease-free survival(DFS: HR=1.51, 95%CI= 1.10-2.07). The subgroup analysis by detection methods revealed an unfavorable OS in breast cancer patients with elevated YKL-40 expression evaluated by IHC(HR=1.39, 95%CI=1.12-1.71) but not by ELISA/RIA. Also, the stratification analysis by ethnicity showed a significant association between increased YKL-40 expression and shorter OS of breast cancer patients in western population(HR=1.51, 95%CI=1.03-2.21) as well as Asian population (HR=1.40, 95%CI= 1.05-1.86). Similarly, the subgroup analysis by detection methods revealed a significantly inferior DFS in breast cancer patients with increased YKL-40 expression disregarding the use of IHC(HR=2.02, 95%CI=1.47-2.79) or ELISA/RIA(HR=1.06, 95%CI= 1.02 -1.10). Additionally, increased YKL-40 expression was found to significantly correlate with larger tumor size (OR=2.38, 95%CI=1.41-4.05).The present meta-analysis indicate that elevated YKL-40 expression is associated with a poor prognosis in breast cancer patients. YKL-40 may serve as a promising predictive biomarker of prognosis of breast cancer.

Serum YKL-40 and MDA levels in Behcet disease.

OBJECTIVE: To measure plasma levels of chitinase-3-like 1 protein and its association with malondialdehyde in Behcet's disease patients. METHODS: The case-control study was conducted at Faculty of Medicine, Ataturk University Erzurum, Turkey, from October 2012 to March 2014, and comprised patients with Behcet's disease and healthy subjects. The patients were divided into two groups, as active and inactive, based on the classification of phases of activity in Behcet's disease. Differences between groups were analysed. SPSS 20 was used for data analysis. RESULTS: Of the 79 participants, 51(64.56%) were patients and 28(35.44%) were controls. The mean age of the first group was 29.45±7.82 years and the second group was 32.21±9.61 years. Among patients, 37(72.55%) were categorised as "active" and 14(27.45%) as "inactive". Median serum Chitinase-3-like 1 protein and malondialdehyde levels were 37.57 ng/mL (interquartilerange: 13.7-293.0 ng/mL) in patients and 26.25 ng/mL (interquartile range: 17.0-44.7 ng/mL) in controls. There was no significant correlation between Chitinase-3-like 1 protein and malondialdehyde (p>0.05). CONCLUSIONS: Chitinase-3-like 1 protein might be associated with Behcet's disease. Elevated malondialdehyde levels were not only the cause of inflammation but also indicator of oxidative stress in Behcet's disease.

Characterization of sputum biomarkers for asthma-COPD overlap syndrome.

Asthma-COPD overlap syndrome (ACOS) is a commonly encountered chronic airway disease. However, ACOS is still a consensus-based clinical phenotype and the underlying inflammatory mechanisms are inadequately characterized. To clarify the inflammatory mediatypical for ACOS, five biomarkers, namely interleukin (IL)-13, myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL), chitinase-like protein (YKL-40), and IL-6, were selected. This study hypothesized that sputum biomarkers relevant for airway inflammation in asthma (IL-13), COPD (MPO, NGAL), or in both asthma and COPD (YKL-40, IL-6) could be used to differentiate ACOS from COPD and asthma. The aim of this study was to characterize the inflammatory profile and improve the recognition of ACOS. Induced sputum levels of IL-13, MPO, NGAL, YKL-40, and IL-6 were measured by enzyme-linked immunosorbent assay/Luminex assay in a Finnish discovery cohort (n=90) of nonsmokers, smokers, and patients with asthma, COPD, and ACOS and validated in a Japanese cohort (n=135). The classification accuracy of potential biomarkers was compared with area under the receiver operating characteristic curves. Only sputum NGAL levels could differentiate ACOS from asthma (P<0.001 and P<0.001) and COPD (P<0.05 and P=0.002) in the discovery and replication cohorts, respectively. Sputum NGAL levels were independently correlated with the percentage of pre-bronchodilator forced expiratory volume in 1 second predicted in multivariate analysis in the discovery and replication cohorts (P=0.001 and P=0.002, respectively). In conclusion, sputum biomarkers reflecting both airway inflammation and remodeling of the tissue show potential in differentiation between asthma, COPD, and ACOS.