Plasma chitotriosidase enzyme activity as a novel therapeutic monitor for cysteamine treatment in nephropathic cystinosis: A retrospective validation study.

BACKGROUND: Cystine-depleting therapy in nephropathic cystinosis is currently monitored via the white blood cell cystine assay, although its application and usefulness are limited by practical and technical issues. Therefore, alternative biomarkers that are widely available, more economical and less technically demanding, while reliably reflecting long-term adherence to cysteamine treatment, are desirable. Recently, we proposed chitotriosidase enzyme activity as a potential novel biomarker for the therapeutic monitoring of cysteamine treatment in cystinosis. In this study, we aimed to validate our previous findings and to confirm the value of chitotriosidase in the management of cystinosis therapy. MATERIALS & METHODS: A retrospective study was conducted on 12 patients treated at the National Institutes of Health Clinical Center and followed up for at least 2 years. Plasma chitotriosidase enzyme activity was correlated with corresponding clinical and biochemical data. RESULTS: Plasma chitotriosidase enzyme activity significantly correlated with WBC cystine levels, cysteamine total daily dosage and a Composite compliance score. Moreover, plasma chitotriosidase was a significant independent predictor for WBC cystine levels, and cut-off values were established in both non-kidney transplanted and kidney transplanted cystinosis patients to distinguish patients with a good versus poor compliance with cysteamine treatment. Our observations are consistent with those of our previous study and validate our findings. CONCLUSIONS: Chitotriosidase enzyme activity is a valid potential alternative biomarker for monitoring cysteamine treatment in nephropathic cystinosis patients. SYNOPSIS: Chitotriosidase enzyme activity is a valid potential alternative biomarker for monitoring cysteamine treatment in nephropathic cystinosis patients.

Chitinases as a potential diagnostic and prognostic biomarker for amyotrophic lateral sclerosis: a systematic review and meta-analysis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the degeneration of motor neurons, and there is currently a lack of reliable diagnostic biomarkers. This meta-analysis aimed to evaluate CHIT1, CHI3L1, and CHI3L2 levels in the cerebrospinal fluid (CSF) or blood and their diagnostic potential in ALS patients. A systematic, comprehensive search was performed of peer-reviewed English-language articles published before April 1, 2023, in PubMed, Scopus, Embase, Cochrane Library, and Web of Science. After a thorough screening, 13 primary articles were included, and their chitinases-related data were extracted for systematic review and meta-analysis. In ALS patients, the CSF CHIT1 levels were significantly elevated compared to controls with healthy control (HC) (SMD, 1.92; 95% CI, 0.78 - 3.06; P < 0.001). CHIT1 levels were elevated in the CSF of ALS patients compared to other neurodegenerative diseases (ONDS) control (SMD, 0.74; 95% CI, 0.22 - 1.27; P < 0.001) and exhibited an even more substantial increase when compared to ALS-mimicking diseases (AMDS) (SMD, 1.15; 95% CI, 0.35 - 1.94, P < 0.001). Similarly, the CSF CHI3L1 levels were significantly higher in ALS patients compared to HC (SMD, 3.16; 95% CI, 1.26 - 5.06, P < 0.001). CHI3L1 levels were elevated in the CSF of ALS patients compared to ONDS (SMD, 0.75; 95% CI, 0.32 - 1.19; P = 0.017) and exhibited a more pronounced increase when compared to AMDS (SMD, 1.92; 95% CI, 0.41 - 3.42; P < 0.001). The levels of CSF chitinases in the ALS patients showed a significant increase, supporting the role of CSF chitinases as diagnostic biomarkers for ALS.

Dynamic personalized risk prediction in chronic heart failure patients: a longitudinal, clinical investigation of 92 biomarkers (Bio-SHiFT study).

The aim of our observational study was to derive a small set out of 92 repeatedly measured biomarkers with optimal predictive capacity for adverse clinical events in heart failure, which could be used for dynamic, individual risk assessment in clinical practice. In 250 chronic HFrEF (CHF) patients, we collected trimonthly blood samples during a median of 2.2 years. We selected 537 samples for repeated measurement of 92 biomarkers with the Cardiovascular Panel III (Olink Proteomics AB). We applied Least Absolute Shrinkage and Selection Operator (LASSO) penalization to select the optimal set of predictors of the primary endpoint (PE). The association between repeatedly measured levels of selected biomarkers and the PE was evaluated by multivariable joint models (mvJM) with stratified fivefold cross validation of the area under the curve (cvAUC). The PE occurred in 66(27%) patients. The optimal set of biomarkers selected by LASSO included 9 proteins: NT-proBNP, ST2, vWF, FABP4, IGFBP-1, PAI-1, PON-3, transferrin receptor protein-1, and chitotriosidase-1, that yielded a cvAUC of 0.88, outperforming the discriminative ability of models consisting of standard biomarkers (NT-proBNP, hs-TnT, eGFR clinically adjusted) - 0.82 and performing equally well as an extended literature-based set of acknowledged biomarkers (NT-proBNP, hs-TnT, hs-CRP, GDF-15, ST2, PAI-1, Galectin 3) - 0.88. Nine out of 92 serially measured circulating proteins provided a multivariable model for adverse clinical events in CHF patients with high discriminative ability. These proteins reflect wall stress, remodelling, endothelial dysfunction, iron deficiency, haemostasis/fibrinolysis and innate immunity activation. A panel containing these proteins could contribute to dynamic, personalized risk assessment.Clinical Trial Registration: 10/05/2013 https://clinicaltrials.gov/ct2/show/NCT01851538?term=nCT01851538&draw=2&rank=1 .

A novel marker of systemic inflammation in psoriasis and related comorbidities: chitotriosidase

Background/aim: Chitotriosidase (ChT) is an enzyme secreted by activated macrophages and neutrophils in response to proinflammatory signals. There is growing evidence indicating that ChT activity reflects the systemic inflammatory status. This study aimed to investigate whether serum ChT activity increased in patients with psoriasis and related comorbidities. Materials and methods: This cross-sectional study included 53 (28 with associated comorbidities and 25 without comorbidities) patients with psoriasis and 52 healthy volunteers. All participants underwent laboratory investigations for serum ChT levels, complete blood count, erythrocyte sedimentation rate, C-reactive protein, and serum lipid levels. Results: The patients with psoriasis showed significantly higher levels of ChT activity as compared to the healthy controls (23.5 ± 11.4 vs. 17.5 ± 10.4 µmol/mL/hour; p = 0.015). Additionally, the ChT activity was significantly higher in patients with comorbidities than in those without (p = 0.042). Conclusion: Our data support the pathogenetic role of inflammatory processes induced by macrophage activation in patients with psoriasis and related comorbidities. We believe that high ChT activity in patients with psoriasis may serve as an early prediction of the possible related comorbidities.

Clinical significance of chitotriosidase in outpatients with advanced heart failure.

The previous studies have shown that plasma chitotriosidase (CHIT) levels increase in many diseases with inflammation. However, there are no reported studies investigating the relationship between CHIT and chronic heart failure (CHF) which is an inflammatory process. Therefore, we aimed to investigate the role of CHIT in diagnosis and severity of CHF in this study. 36 patients (50% male, mean age 63.17±10.18 years) with left ventricular ejection fraction <40% and 27 controls (44% male, mean age 61.33±8.73 years) were included in this study. Patients with CHF were divided into two groups as ischemic heart failure (IHF) and non-ischemic heart failure (NIHF) according to the underlying etiology. Plasma CHIT and N-terminal pro brain natriuretic peptide (NT-proBNP) levels were measured by ELISA method. Plasma CHIT and NT-proBNP levels were higher in patients with CHF than in controls (CHIT 931.25±461.39 ng/mL, 232.79±61.28 ng/mL, p<0.001; NT-proBNP, 595.31±428.11 pg/mL vs 78.13±30.47 pg/L; p<0.001). Also, the levels of these parameters increased in IHF compared with NIHF (CHIT, 1139.28±495.22 ng/mL, 671.22±237.21 ng/mL, p=0.002; NT-proBNP, 792.87±461.26 pg/mL vs 348.36±202.61 pg/mL, p=0.001) and there was a strong correlation between NT-proBNP and CHIT (r=0.969, p<0.001). According to this study findings, plasma CHIT level increases in CHF and its increased levels are correlated with NT-proBNP which is used diagnosis and prognosis of HF.

Key Players and Biomarkers of the Adaptive Immune System in the Pathogenesis of Sarcoidosis.

Sarcoidosis is a systemic inflammatory disease characterized by development of granulomas in the affected organs. Sarcoidosis is often a diagnosis of exclusion, and traditionally used tests for sarcoidosis demonstrate low sensitivity and specificity. We propose that accuracy of diagnosis can be improved if biomarkers of altered lymphocyte populations and levels of signaling molecules involved in disease pathogenesis are measured for patterns suggestive of sarcoidosis. These distinctive biomarkers can also be used to determine disease progression, predict prognosis, and make treatment decisions. Many subsets of T lymphocytes, including CD8+ T-cells and regulatory T-cells, have been shown to be dysfunctional in sarcoidosis, and the predominant CD4+ T helper cell subset in granulomas appears to be a strong indicator of disease phenotype and outcome. Studies of altered B cell populations, B cell signaling molecules, and immune complexes in sarcoidosis patients reveal promising biomarkers as well as possible explanations of disease etiology. Furthermore, examined biomarkers raise questions about new treatment methods and sarcoidosis antigens.

The changing features of serum adropin, copeptin, neprilysin and chitotriosidase which are associated with vascular endothelial function in type 2 diabetic retinopathy patients.

AIMS: Adropin (AD), copeptin (CP), neprilysin (NEP) and chitotriosidase (CHIT1) have been associated with the regulation of vascular endothelial function. In this work, we analyzed the plasma concentrations of cytokines (AD, CP, NEP and CHIT1) in type 2 diabetic patients with or without retinopathy (DR) to predict the risk of DR for diabetic patients. METHOD: A total of 392 patients diagnosed as type 2 diabetes mellitus (T2DM) and 120 healthy volunteers as a control group were enrolled in this study. T2DM patients were divided into three groups: diabetes without retinopathy (NDR, n = 174) group, non-proliferative diabetic retinopathy (NPDR, n = 118) group and proliferative diabetic retinopathy (PDR, n = 100) group. The serum AD, CP, NEP and CHIT1 levels of subjects were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: We reported a significant decrease in AD and a significant increase in CP, NEP and CHIT1 in NDR as well as DR patients when compared with controls (p < 0.05), the lower level of AD and significantly higher levels of CP, NEP and CHIT1 were seen in DR patients compared to NDR group (p < 0.05), at the same time, we observed the lowest level of AD and the highest levels of CP, NEP and CHIT1 in the PDR group. Logistic regression analysis showed that AD was a protective factor for DR, conversely, CP, NEP and CHIT1 were the independent risk factors (p < 0.05). Moreover, receiver operating characteristic curve analyses indicated that CP had greater diagnosis capacity with an AUC (the areas under the ROC curve) of 0.901 than AD, NEP, CHIT1 for DR patients. CONCLUSION: The decreased AD level and the elevated CP, NEP and CHIT1 levels involved in vascular endothelial function may be evidence facilitating the presence of DR. Thereby they can be explored to use as promising non-invasive biomarkers for prediction of DR severity, distinguishing DR from diabetic patients.

Real-world effectiveness of eliglustat in treatment-naïve and switch patients enrolled in the International Collaborative Gaucher Group Gaucher Registry.

Eliglustat is a first-line oral therapy for adults with Gaucher disease type 1 (GD1) with extensive, intermediate, or poor CYP2D6-metabolizer phenotypes (90% of patients). We report real-world outcomes after 2 years of eliglustat therapy in the International Collaborative Gaucher Group Gaucher Registry (NCT00358943). As of January 2019, baseline and 2-year data (±1 year) were available for 231 eliglustat-treated GD1 patients: 19 treatment-naïve (zero splenectomized) and 212 ERT patients who switched to eliglustat (36 splenectomized). Most patients (89%) were from the United States, where eliglustat was first approved. In treatment-naïve patients, mean hemoglobin increased from 12.4 to 13.4 g/dL (P = .004, n = 18), mean platelet count increased from 113 to 156 × 109 /L (P < .001, n = 17); mean spleen volume decreased from 7.4 to 3.5 multiples of normal (MN) (P = .02, n = 7); mean liver volume remained normal (n = 7), and median spine Z-score was unchanged (-1.3 to -1.2, n = 6). In non-splenectomized switch patients, mean hemoglobin remained stable/non-anemic (n = 167); mean platelet count remained stable/normal (n = 165); mean spleen volume decreased from 3.3 to 2.8 MN (P < .001, n = 64); mean liver volume remained normal (n = 63), and median lumbar spine Z-score improved from -0.7 to -0.4 (P = .014, n = 68). In splenectomized switch patients, mean hemoglobin remained stable/non-anemic (n = 31); mean platelet count increased from 297 to 324 × 109 /L (non-significant, n = 29); mean liver volume remained normal (n = 13); median spine Z-score improved from -0.8 to -0.6 (non-significant, n = 11). Median chitotriosidase decreased in all groups (P < .01 for all). These real-world results are consistent with eliglustat clinical trial results demonstrating long-term benefit in treatment-naïve patients and stability in ERT switch patients.

Chitotriosidase as a Novel Biomarker for Therapeutic Monitoring of Nephropathic Cystinosis.

BACKGROUND: Nephropathic cystinosis, a hereditary lysosomal storage disorder caused by dysfunction of the lysosomal cotransporter cystinosin, leads to cystine accumulation and cellular damage in various organs, particularly in the kidney. Close therapeutic monitoring of cysteamine, the only available disease-modifying treatment, is recommended. White blood cell cystine concentration is the current gold standard for therapeutic monitoring, but the assay is technically demanding and is available only on a limited basis. Because macrophage-mediated inflammation plays an important role in the pathogenesis of cystinosis, biomarkers of macrophage activation could have potential for the therapeutic monitoring of cystinosis. METHODS: We conducted a 2-year prospective, longitudinal study in which 61 patients with cystinosis who were receiving cysteamine therapy were recruited from three European reference centers. Each regular care visit included measuring four biomarkers of macrophage activation: IL-1ß, IL-6, IL-18, and chitotriosidase enzyme activity. RESULTS: A multivariate linear regression analysis of the longitudinal data for 57 analyzable patients found chitotriosidase enzyme activity and IL-6 to be significant independent predictors for white blood cell cystine levels in patients of all ages with cystinosis; a receiver operating characteristic analysis ranked chitotriosidase as superior to IL-6 in distinguishing good from poor therapeutic control (on the basis of white blood cell cystine levels of <2 nmol 1/2 cystine/mg protein or ≥2 nmol 1/2 cystine/mg protein, respectively). Moreover, in patients with at least one extrarenal complication, chitotriosidase significantly correlated with the number of extrarenal complications and was superior to white blood cell cystine levels in predicting the presence of multiple extrarenal complications. CONCLUSIONS: Chitotriosidase enzyme activity holds promise as a biomarker for use in therapeutic monitoring of nephropathic cystinosis.

Clinical, ocular motor, and imaging profile of Niemann-Pick type C heterozygosity.

OBJECTIVE: To characterize subclinical abnormalities in asymptomatic heterozygote NPC1 mutation carriers as markers of neurodegeneration. METHODS: Motor function, cognition, mood, sleep, and smell function were assessed in 20 first-degree heterozygous relatives of patients with Niemann-Pick disease type C (NPC) (13 male, age 52.7 ± 9.9 years). Video-oculography and abdominal ultrasound with volumetry were performed to assess oculomotor function and size of liver and spleen. NPC biomarkers in blood were analyzed. 18F-fluorodesoxyglucose PET was performed (n = 16) to detect patterns of brain hypometabolism. RESULTS: NPC heterozygotes recapitulated characteristic features of symptomatic NPC disease and demonstrated the oculomotor abnormalities typical of NPC. Hepatosplenomegaly (71%) and increased cholestantriol (33%) and plasma chitotriosidase (17%) levels were present. The patients also showed signs seen in other neurodegenerative diseases, including hyposmia (20%) or pathologic screening for REM sleep behavior disorder (24%). Cognitive function was frequently impaired, especially affecting visuoconstructive function, verbal fluency, and executive function. PET imaging revealed significantly decreased glucose metabolic rates in 50% of participants, affecting cerebellar, anterior cingulate, parieto-occipital, and temporal regions, including 1 with bilateral abnormalities. CONCLUSION: NPC heterozygosity, which has a carrier frequency of 1:200 in the general population, is associated with abnormal brain metabolism and functional consequences. Clinically silent heterozygous gene variations in NPC1 may be a risk factor for late-onset neurodegeneration, similar to the concept of heterozygous GBA mutations underlying Parkinson disease.

Increased Chitotriosidase Is Associated With Aspergillus and Frequent Exacerbations in South-East Asian Patients With Bronchiectasis.

BACKGROUND: Chitinase activity is an important innate immune defence mechanism against infection that includes fungi. The 2 human chitinases: chitotriosidase (CHIT1) and acidic mammalian chitinase are associated to allergy, asthma, and COPD; however, their role in bronchiectasis and bronchiectasis-COPD overlap (BCO) is unknown. RESEARCH QUESTION: What is the association between chitinase activity, airway fungi and clinical outcomes in bronchiectasis and bronchiectasis-COPD overlap? STUDY DESIGN AND METHODS: A prospective cohort of 463 individuals were recruited across five hospital sites in three countries (Singapore, Malaysia, and Scotland) including individuals who were not diseased (n = 35) and who had severe asthma (n = 54), COPD (n = 90), bronchiectasis (n = 241) and BCO (n = 43). Systemic chitinase levels were assessed for bronchiectasis and BCO and related to clinical outcomes, airway Aspergillus status, and underlying pulmonary mycobiome profiles. RESULTS: Systemic chitinase activity is elevated significantly in bronchiectasis and BCO and exceed the activity in other airway diseases. CHIT1 activity strongly predicts bronchiectasis exacerbations and is associated with the presence of at least one Aspergillus species in the airway and frequent exacerbations (≥3 exacerbations/y). Subgroup analysis reveals an association between CHIT1 activity and the "frequent exacerbator" phenotype in South-East Asian patients whose airway mycobiome profiles indicate the presence of novel fungal taxa that include Macroventuria, Curvularia and Sarocladium. These taxa, enriched in frequently exacerbating South-East Asian patients with high CHIT1 may have potential roles in bronchiectasis exacerbations. INTERPRETATION: Systemic CHIT1 activity may represent a useful clinical tool for the identification of fungal-driven "frequent exacerbators" with bronchiectasis in South-East Asian populations.

The Role of Urinary Calcium and Chitotriosidase in a Cohort of Chronic Sarcoidosis Patients.

BACKGROUND: Calcium metabolism alterations are quite common in sarcoidosis and have been correlated with disease activity. OBJECTIVES: The aim of the study was to investigate the clinical significance of calcium metabolism alterations in patients with chronic sarcoidosis. We paid particular attention to associations with specific disease phenotypes and chitotriosidase (CTO) expression. METHODS: 212 chronic sarcoidosis patients (mean age 56.07 ± 12 years; 97 males) were retrospectively recruited. Demographic, clinical, functional, and radiological data, and serum-urinary calcium metabolism were entered into an electronical database for analysis. Levels of CTO and angiotensin-converting enzyme (ACE) were measured and bone mineral density and lung function tests were conducted. RESULTS: Hypercalciuria and hypercalcemia were observed in 18.8 and 1.8% of patients, respectively. Urinary calcium levels correlated with CTO activity (r = 0.33, p = 0.0042). Patients with worsening persistent disease showed the highest levels of urinary calcium. Diffusing capacity of the lung for carbon monoxide (DLCO) percentage correlated inversely with urinary calcium (r = 0.1482; p = 0.0397). CONCLUSIONS: Calcium metabolism alteration, particularly hypercalciuria, was observed in a significant percentage of patients of sarcoidosis. Urinary calcium was correlated with clinical status, DLCO, and serum CTO activity, suggesting its potential role as a biomarker of the activity and severity of sarcoidosis.

Chitotriosidase Activity in Plasma and COPD Exacerbations.

INTRODUCTION: This study aimed to determine the association between plasma chitotriosidase activity and the clinical characteristics and exacerbation rate of COPD patients. METHODS: The study comprised 97 patients with COPD. Their clinical characteristics and a history of exacerbations in the last 12 months were noted. Plasma chitotriosidase activity was determined. Patients were followed up for 12 months, and the number of moderate and severe exacerbations during this period was recorded. RESULTS: Chitotriosidase activity positively correlated with patient age (rho = 0.217, p = 0.036) and inversely with CAT (rho = - 0.240, p = 0.020). There was no correlation with lung function. Chitotriosidase activity was significantly lower in patients with a history of ≥ 2 exacerbations compared to patients without a history of exacerbations (93 [38-312] vs. 264 [168-408] nmol/h/mL, p = 0.033). Overall, there was no difference in chitotriosidase activity between patients with or without observed exacerbations. Patients with a history of ≥ 1 exacerbation and ≥ 1 observed exacerbation had higher chitotriosidase activity compared to patients without further exacerbations (240 [144-456] vs. 52 [39-240] nmol/h/mL, p = 0.035). Multivariate analysis identified FEV1 (HR 0.976, 95% CI 0.956-0.996, p = 0.016) and blood eosinophil percentage (HR 1.222, 95% CI 1.048-1.424, p = 0.011) as independent predictors of future exacerbations in the total patient population, while in patients with a history of ≥ 1 exacerbation ,the only independent predictor was chitotriosidase activity (HR per 10 nmol/h/mL 1.028, 95% CI 1.002-1.055, p = 0.037). CONCLUSION: While mixed associations between chitotriosidase activity and clinical outcomes were seen, chitotriosidase activity could be a predictor of future exacerbations in patients with a history of ≥ 1 exacerbation in the past  12 months.

Cross-sectional and longitudinal measures of chitinase proteins in amyotrophic lateral sclerosis and expression of CHI3L1 in activated astrocytes.

OBJECTIVE: Amyotrophic lateral sclerosis (ALS) is a complex disease with numerous pathological mechanisms resulting in a heterogeneous patient population. Using biomarkers for particular disease mechanisms may enrich a homogeneous subset of patients. In this study, we quantified chitotriosidase (Chit-1) and chitinase-3-like protein 1 (CHI3L1), markers of glial activation, in cerebrospinal fluid (CSF) and plasma and determined the cell types that express CHI3L1 in ALS. METHODS: Immunoassays were used to quantify Chit-1, CHI3L1 and phosphorylated neurofilament heavy chain levels in longitudinal CSF and matching plasma samples from 118 patients with ALS, 17 disease controls (DCs), and 24 healthy controls (HCs). Immunostaining was performed to identify and quantify CHI3L1-positive cells in tissue sections from ALS, DCs and non-neurological DCs. RESULTS: CSF Chit-1 exhibited increased levels in ALS as compared with DCs and HCs. CSF CHI3L1 levels were increased in ALS and DCs compared with HCs. No quantitative differences were noted in plasma for either chitinase. Patients with ALS with fast-progressing disease exhibited higher levels of CSF Chit-1 and CHI3L1 than patients with slow-progressing disease. Increased numbers of CHI3L1-positive cells were observed in postmortem ALS motor cortex as compared with controls, and these cells were identified as a subset of activated astrocytes located predominately in the white matter of the motor cortex and the spinal cord. CONCLUSIONS: CSF Chit-1 and CHI3L1 are significantly increased in ALS, and CSF Chit-1 and CHI3L1 levels correlate to the rate of disease progression. CHI3L1 is expressed by a subset of activated astrocytes predominately located in white matter.

Chitotriosidase: a biomarker of activity and severity in patients with sarcoidosis.

BACKGROUND: Serum chitotriosidase is a promising biomarker that has shown high specificity and sensitivity in patients with sarcoidosis. The aim of this study was to investigate correlations between serum chitotriosidase, clinical phenotypes, disease localizations and different radiological lung involvement and to identify clinical features associated with over-expression of chitotriosidase in a large cohort of sarcoidosis patients. METHODS: Chitotriosidase activity was evaluated in a population of 694 consecutive patients (males 39%, age 55.8 ± 12.8 years). Clinical and respiratory functional characteristics, Clinical Outcome Scale (COS) classification, clinical phenotypes proposed by the GenPhenResA project, and radiological assessment, including CT scan, were collected. Serum sampling and clinical and functional assessments at follow-up were also included. RESULTS: Significantly higher chitotriosidase activity was observed in sarcoidosis patients than in healthy controls (p < 0.0001). Evidence of lung fibrosis with reticular abnormalities and traction bronchiectasis at High resolution CT, presence of multiple extrapulmonary sarcoid localizations and increased 24-h urinary excretion of calcium were associated with significantly higher chitotriosidase activity (p < 0.005). Patients with remitted or minimal disease had lower values of chitotriosidase than patients with persistent disease. At follow-up, patients who required an increase in steroid dose showed an increase in its activity. CONCLUSIONS: Chitotriosidase is a reliable biomarker of sarcoidosis. It is increased in patients with sarcoidosis correlating with disease activity, severity and multiorgan dissemination. Steroid therapy tended to reduce chitotriosidase expression, however it responded in cases of disease relapse.

Dramatically changed immune-related molecules as early diagnostic biomarkers of non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is the main type of lung cancer, with a low 5-year survival rate because of the absence of effective clinical biomarkers for early diagnosis. Based on the immunosurveillance theory, we proposed that changes in the immune system are more pronounced than tumour-associated antigens during the early stage of cancer. Therefore, a new strategy was designed to screen early diagnostic biomarkers from peripheral leukocytes in early-stage NSCLCs with transcriptome sequencing. A total of 358 immune-related differentially expressed genes were identified between early-NSCLC patients and healthy individuals. Orosomucoid-1 (ORM1, a acute phase protein), the total ORM and chitotriosidase-1 (involved in degradation of chitobiose) were selected for further verification in 210 serum samples by western blotting, ELISA and nephelometry immunoassay (based on immuno-scatter turbidmetry). Receiver operating characteristic curve analysis show that ORM1 and total ORM have excellent diagnostic efficacies, with area under the curve of 0.862 and 0.920, respectively, which significantly distinguished very early-NSCLC (IA) from healthy samples. Flow cytometry results showed that CD15+ neutrophils made up 73% of ORM1+ peripheral leukocytes. In mouse lung cancer model, serum ORM1, but not liver ORM1, changed significantly in the early stage of NSCLC. ORM1 expression in peripheral leukocytes was regulated by TGF-ß and mediated by the TGF-ß/Smad signalling pathway. Our results indicated that combined ORM and TGF-ß could be a promising clinical biomarker in the diagnosis of early NSCLC.

Combined application of angiotensin converting enzyme and chitotriosidase analysis improves the laboratory diagnosis of sarcoidosis.

Establishing the diagnosis of sarcoidosis most often requires biopsy and histopathologic evaluation, since there is no single marker with sufficient specificity and sensitivity for the disease. Our aims were to determine and compare the diagnostic accuracies of several potential biomarkers and to develop a combined biomarker analysis tool for the diagnosis of sarcoidosis. 133 healthy individuals and 104 patients with suspected sarcoidosis and diagnostic thoracic surgery were enrolled into this study. Histopathologic results were contrasted to biomarker levels of chitotriosidase (CTO), serum amyloid-A (SAA), soluble interleukin-2 receptor (sIL-2R), lysozyme (LZM) or angiotensin converting enzyme (ACE). Sarcoidosis was confirmed by histopathology in 69 patients. CTO activity, sIL-2R concentration and ACE activity could discriminate between sarcoidosis and control patients, while SAA and LZM concentrations could not. A new combined parameter, which was derived from the multiplication of ACE by CTO activities (double product) showed the best diagnostic accuracy in this clinical study: (AUC = 0.898, sensitivity: 90.5%, specificity: 79.3%, positive and negative predictive values: 90.5% and 79.3%, respectively). Sarcoidosis can be diagnosed with the combined analysis of ACE and CTO activities more accurately than with single serum biomarkers in the absence of invasive biopsy in the majority of cases with pulmonary manifestation of sarcoidosis.

Biomarkers and newer laboratory investigations in the diagnosis of sepsis.

Sepsis is a major cause of death in hospitalised patients accounting for mortality rates as high as 60% and, hence, is called 'a hidden public health disaster'. Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis is not a disease but is a clinical syndrome, where the initial features are nonspecific resulting in delayed diagnosis. Lack of specific laboratory tests to diagnose the syndrome adds to the diagnostic confusion. Failure to identify sepsis in the early stages itself delays effective treatment resulting in high morbidity and mortality. Various biomarkers and newer laboratory tests help to address these issues. However, to date there is no ideal test to diagnose sepsis. The most commonly used markers are C-reactive protein (CRP) and procalcitonin (PCT). There are around 180 biomarkers reported to be useful in sepsis. In addition to CRP and PCT, various emerging laboratory markers, such as like serum amyloid A, soluble triggering receptor expressed on myeloid cell-1, mannan and antimannan antibodies, and interferon γ inducible protein-10 etc., have been reviewed and their clinical usefulness discussed in this paper.

Overexpression of chitotriosidase and YKL-40 in peripheral blood and sputum of healthy smokers and patients with chronic obstructive pulmonary disease.

Background: Despite the absence of endogenous chitin in humans, chitinases are present in the serum of healthy subjects and their levels are increased in a variety of chronic inflammatory conditions. It has been shown that chitotriosidase and structurally related chitinase-like protein-YKL-40 contribute to the pathogenesis of COPD. However, details regarding the relation of their systemic and local airways levels remain unknown. Objectives: To examine peripheral blood and sputum chitotriosidase and YKL-40 expression in smokers and patients with COPD. Methods: Forty patients with COPD, 20 healthy smokers and 10 healthy never-smokers were studied. Serum and induced sputum chitotriosidase protein and activity levels, YKL-40 concentrations, and their gene expression in sputum cells and peripheral blood mononuclear cells (PBMC) were evaluated. Results: Both chitotriosidase protein levels and activity were higher in sputum obtained from COPD subjects compared to healthy never-smokers (P<0.05 and P<0.01, respectively). A similar pattern was observed for PBMC chitotriosidase mRNA expression (P<0.001). YKL-40 serum concentrations were elevated in healthy smokers and COPD subjects compared to healthy never-smokers (P<0.001 and P<0.01, respectively). In sputum, YKL-40 levels were increased in COPD compared to healthy never-smokers (P<0.01). PBMC YKL-40 mRNA expression was increased in COPD and healthy smokers compared to healthy never-smokers (P<0.0001). No associations were found between chitotriosidase or YKL-40 peripheral blood levels and sputum levels. Conclusions: Our results demonstrate that chitotriosidase and YKL-40 are overexpressed in peripheral blood and airways in both healthy smokers and COPD subjects which may indicate smoking-related activation of macrophages, neutrophils, and epithelial cells.

Oxysterol/chitotriosidase based selective screening for Niemann-Pick type C in infantile cholestasis syndrome patients.

BACKGROUND: Niemann-Pick disease type C (NP-C) is an inherited neurodegenerative disease (1 per 100 000 newborns) caused by NPC proteins impairment that leads to unesterified cholesterol accumulation in late endosomal/lysosomal compartments. To date the NP-C diagnostics is usually based on cholesterol detection in fibroblasts using an invasive and time-consuming Filipin staining and we need more arguments to widely introduce oxysterols as a biomarkers in NP-C. METHODS: Insofar as NP-C represents about 8% of all infant cholestases, in this prospective observational study we tried to re-assess the specificity plasma oxysterol and chitotriosidase as a biochemical screening markers of NP-C in children with cholestasis syndrome of unknown origin. For 108 patients (aged from 2 weeks to 7 years) the levels of cholestane-3ß,5α,6ß-triol (C-triol) and chitotriosidase (ChT) were measured. For patients with elevated C-triol and/or ChT the NPC1 and NPC2 genes were Sanger-sequenced and 47 additional genes (from the custom liver damage panel) were NGS-sequenced. RESULTS: Increased C-triol level (> 50 ng/ml) was detected in 4 (of 108) infants with cholestasis syndrome of unknown origin, with following molecular genetic NP-C diagnosis for one patient. Plasma cholesterol significantly correlates with C-triol (p < 0.05). NGS of high C-triol infants identified three patients with mutations in JAG1 (Alagille syndrome) and ABCB11 (Byler disease) genes. Increased ChT activity was detected in 8 (of 108) patients with various aetiologies, including NP-C, Byler disease and biliary atresia. CONCLUSION: Combined analysis of ChT activity and C-triol levels is an effective method for identifying NP-C.