A unique plasma proteomic profiling with imbalanced fibrinogen cascade in patients with Kawasaki disease

Proteomics approach for biomarker discovery in Kawasaki disease

INTRODUCTION

Kawasaki disease (KD) is a medium vessel vasculitis mainly affecting children below the age of 5. KD is the leading cause of acquired heart disease in developed countries. Diagnosis of KD is clinical, and there are no pathognomonic laboratory tests to confirm the diagnosis. There is a paucity of studies that have utilized proteomic approach for biomarker discovery in KD. Identification of these biomarkers may be helpful for early and more effective diagnosis and may aid in the treatment of KD.

AREA COVERED

The present review focuses on studies that have utilized the proteomic approach in the identification of biomarkers in patients with KD. We have divided these biomarkers into three different categories: the biomarkers used for (a) assessment of risk of KD; (b) assessment of risk of coronary artery aneurysms; and (c) assessment of treatment resistance.

EXPERT OPINION

Efforts to improve the clinical and diagnostic evaluation of KD have focused on general markers of inflammation that are not specific for KD. Identification of a proteomic-based biomarker can reliably and specifically differentiate KD from other diseases and could help in the prompt diagnosis. Comprehensive analysis of the serum proteome of patients with KD may be helpful in identifying candidate protein biomarkers.

EFFICACY OF INTRAVENOUS IMMUNOGLOBULIN ALONE ON CORONARY ARTERY LESION REDUCTION IN KAWASAKI DISEASE

Background

Though Aspirin and intravenous immunoglobulin (IVIG) remain the standard treatments for Kawasaki Disease (KD) to minimize coronary artery damage, the duration and dosage of aspirin are inconsistent across hospitals. However, the lack of multi-center randomized trials prevents definitive answers to the impact of high-dose aspirin.

Methods

This clinical trial was structured as a prospective, evaluator-blinded, multi-center randomized controlled trial with two parallel arms, aiming to assess the effectiveness of IVIG as a standalone primary therapy of KD in comparison to the combination of IVIG with high-dose aspirin therapy. KD patients were enrolled between September, 2016 and August, 2019. A final cohort of 134 patients were randomly assigned to the standard and test groups with 69 and 65 patients, respectively. The Standard group received IVIG (2 g/kg) along with aspirin (80-100 mg/kg/day) until fever subsided for 48 hours. The test group received IVIG (2 g/kg) alone. Following the initial treatment, both groups received a daily aspirin dose (3-5 mg/kg) for six weeks. The primary outcome measure was the occurrence of coronary artery lesions (CAL) at the 6-8 weeks mark. The secondary outcome is IVIG resistance.

Results

The overall rate of CAL in test group decreased from 10.8% at diagnosis to 1.5% and 3.1% at 6 weeks and 6 months, respectively. The CAL rate of standard group declined from 13.0% to 2.9% and 1.4%, with no statistically significant difference (P>0.1) in the frequency of CAL between the two groups. Furthermore, no statistically significant differences were found for treatment (P>0.1) and prevention (P>0.1) effect between the two groups.

Conclusions

This marks the first prospective multi-center randomized controlled trial comparing the standard treatment of KD using IVIG plus high-dose aspirin against IVIG alone. Our analysis indicates that addition of high-dose aspirin during initial IVIG treatment is neither statistically significant nor clinically meaningful for CAL reduction.

Registration

URL: http://www.clinicaltrials.gov ; identifier: NCT02951234.

What is New?

This study represents the first multi-center randomized controlled trial investigating the efficacy of high-dose aspirin or intravenous immunoglobulin (IVIG) during the acute stage of KD. This study assessed the impact of discontinuing high-dose aspirin (80-100 mg/kg/day) on the occurrence of CAL during the acute phase treatment of Kawasaki Disease.No significant differences were observed between high-dose aspirin plus IVIG treatment and IVIG alone treatment in terms of the frequency of abnormal coronary artery abnormalities. Additionally, our analysis revealed no statistically significant differences in either the treatment effect (the number of cases successfully treated) or prevention effect (the prevention of new cases) between these two treatments.

What Are the Clinical Implications?

Comparison analysis indicated the non-inferiority between two groups with or without high-dose aspirin.Administering the standard 2 g/kg/day IVIG without high-dose aspirin (80-100 mg/kg/day) during the acute phase therapy for KD does not increase the risk of coronary artery lesions, which are a primary cause of morbidity and mortality in KD patients.Addition of high-dose aspirin during initial IVIG treatment is not statistically significant or clinically meaningful.

Apoptosis Inhibitor of Macrophages Contributes to the Chronicity of Mycobacterium avium Infection by Promoting Foamy Macrophage Formation

In Mycobacterium avium infections, macrophages play a critical role in the host defense response. Apoptosis inhibitor of macrophage (AIM), also known as CD5L, may represent a novel supportive therapy against various diseases, including metabolic syndrome and infectious diseases. The mechanisms of AIM include modulating lipid metabolism in macrophages and other host cells. We investigated the role of AIM in M. avium infections in vitro and in vivo. In a mouse model of M. avium pneumonia, foamy macrophages were induced 6 wk after infection. The bacteria localized in these macrophages. Flow cytometric analysis also confirmed that the percentage of CD11chighMHCclassIIhigh interstitial and alveolar macrophages, a cell surface marker defined as foamy macrophages, increased significantly after infection. AIM in alveolar lavage fluid and serum gradually increased after infection. Administration of recombinant AIM significantly increased the number of bacteria in the lungs of mice, accompanied by the induction of inflammatory cytokine and iNOS expression. In mouse bone marrow-derived macrophages, the mRNA expression of AIM after M. avium infection and the amount of AIM in the supernatant increased prior to the increase in intracellular bacteria. Infected cells treated with anti-AIM Abs had fewer bacteria and a higher percentage of apoptosis-positive cells than infected cells treated with isotype control Abs. Finally, AIM in the sera of patients with M. avium-pulmonary disease was measured and was significantly higher than in healthy volunteers. This suggests that AIM production is enhanced in M. avium-infected macrophages, increasing macrophage resistance to apoptosis and providing a possible site for bacterial growth.

Kawasaki disease: characteristics, diagnosis, and unusual presentations

Introduction: Kawasaki disease (KD) is one of the commonest pediatric vasculitides and is associated with a significant risk of development of coronary artery abnormalities if left untreated. Areas covered: In this review, we have highlighted the incomplete and unusual presentations of KD and also emphasize the controversies pertaining to 2D echocardiography in KD. A PubMed search was performed regarding diagnosis and unusual presentations of KD. Expert opinion: Diagnosis of KD is essentially clinical and based on recognition of typical clinical features that may appear sequentially and all signs and symptoms may not be present at one point of time. There is no confirmatory laboratory test for diagnosis of this condition. Further complicating the picture is the fact that incomplete and atypical forms KD may be seen in up to 50% patients. Although 2D echocardiography continues to be the preferred imaging modality for cardiac assessment in patients with KD, it has its limitations.

Plasma proteomics and the paediatric patient

INTRODUCTION

Plasma proteomics has been extensively utilized for studies that investigate various disease settings (e.g. cardiovascular disease), as well as to monitor the effect of pharmaceuticals on the plasma proteome (e.g. chemotherapy). However, plasma proteomic studies focusing on children represent a very small proportion of the plasma proteomic studies completed to date. Early disease detection and prevention is critical in pediatrics, as children must live with the disease outcomes for many years and often carry negative outcomes into adulthood. Pediatrics represents an area of plasma proteomics that is about to undergo a significant expansion. Areas covered: This review is based on a PubMed search focusing on five keywords that are plasma, biomarkers, pediatric, proteomics, and children. It is a comprehensive summary of plasma proteomic studies specific to the pediatric patient and discusses aspects such as the clinical setting, sample size, methodological approaches and outlines the significance of the findings. Expert commentary: Plasma proteomics is expanding significantly as a result of major advancements in proteomic technology. This is in synergy with the growing focus on true early disease detection and prevention in early life. We are about to see a new era of advanced medical science built from pediatric proteomics.

Phosphorylated proteomics analysis of human coronary artery endothelial cells stimulated by Kawasaki disease patients serum

BACKGROUND

Kawasaki disease (KD) is an acute febrile childhood systemic vasculitis that disturbs coronary arteries. The pathogenesis remains unknown. The study of phosphorylated proteins helps to elucidate the relevant pathophysiological mechanisms of cardiovascular disease. However, few researches explored phosphorylated proteins in KD patients.

METHODS

We compared phosphoprotein profiles of HCAECs stimulated by the serum of KD patients and normal children using iTRAQ technology, TiO₂ enrichment phosphorylated peptide and MS analysis. Then we conducted the functional analysis by ClueGO and the biological interaction networking analysis by ReactomeFIViz. Western blotting was performed to identify the hub proteins.

RESULTS

Our results revealed that phosphorylation of 148 proteins showed different intensities between the two HCAECs groups, which are enriched in MAPK, VEGFR, EGFR, Angiopoietin receptor, mTOR, FAK signaling pathway and so on. Through the Network Analyzer analysis, the hub proteins are CDKN1A, MAPK1 and POLR2A, which were experimentally validated.

CONCLUSION

In summary, we provided evidence addressing the valuable phosphorylation signaling that could be useful resource to understand the molecular mechanism and the potential targets for novel therapy of KD.

MiR-222-3p in Platelets Serves as a Distinguishing Marker for Early Recognition of Kawasaki Disease

Kawasaki disease (KD) is an acute vasculitis, which leads to 20% of sufferers developing coronary artery aneurysm in children if not appropriately treated. Therefore, the early diagnosis of KD is essential for alleviating the risk of developing heart disease. MicroRNAs (miRNAs) are a large class of small non-coding RNAs which post-transcriptionally regulate gene expression and have been shown to play critical roles in numerous biological processes and diseases. In this study, we used high-throughput miRNA sequencing and found dozens of miRNAs are highly expressed in platelets. By comparing the miRNA expression profile of platelets of acute KD patients and other febrile patients, miR-222-3p is validated to be significantly upregulated in platelets of acute KD patients. Furthermore, KEGG pathway analysis shows that targets of miR-222-3p are enriched in immune-related signaling pathways. Our study uncovers the potential of miR-222-3p in platelets as biomarker for early diagnosis of Kawasaki disease.

Biomarkers for Kawasaki Disease: Clinical Utility and the Challenges Ahead

Kawasaki disease (KD) has replaced acute rheumatic fever as the most common cause of acquired heart disease in children in the developed world and is increasingly being recognized from several developing countries. It is a systemic vasculitis with a predilection for coronary arteries. The diagnosis is based on a constellation of clinical findings that appear in a temporal sequence. Quite understandably, this can become a problem in situations wherein the clinical features are not typical. In such situations, it can be very difficult, if not impossible, to arrive at a diagnosis. Several biomarkers have been recognized in children with acute KD but none of these has reasonably high sensitivity and specificity in predicting the course of the illness. A line up of inflammatory, proteomic, gene expression and micro-RNA based biomarkers has been studied in association with KD. The commonly used inflammatory markers e.g. erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and total leucocyte counts (TLC) lack specificity for KD. Proteomic studies are based on the identification of specific proteins in serum, plasma and urine by gel electrophoresis. A host of genetic studies have identified genes associated with KD and some of these genes can predict the course and coronary outcomes in the affected individuals. Most of these tests are in the early stages of their development and some of these can predict the course, propensity to develop coronary artery sequelae, intravenous immunoglobulin (IVIg) resistance and the severity of the illness in a patient. Development of clinical criteria based on these tests will improve our diagnostic acumen and aid in early identification and prevention of cardiovascular complications.

Dynamic evaluation of hemostasis in the acute phase of Kawasaki disease using comprehensive coagulation functional assays

INTRODUCTION

Kawasaki disease (KD) is a systemic vasculitis involving coronary arteries, sometimes resulting in aneurysms and myocardial infarction. Hyper-coagulability in the acute-phase of KD is indicated in some circumstances based on changes of individual clotting factors. Comprehensive coagulation assays, clot waveform analysis (CWA) and thrombin/plasmin generation assay (T/P-GA), have been developed to assess physiological hemostasis, but these techniques have not been applied in KD.

METHODS

We utilized both assays to analyze coagulation function in KD children (n = 42) prior to intravenous-immunoglobulin (IVIG) treatment (Pre), 1-week (1W) and 1-month (1M) post-IVIG.

RESULTS

In CWA, the clot time (CT) pre-treatment was prolonged, and was significantly shortened at 1W and 1M. However, the maximum coagulation velocity (|min1|) and acceleration (|min2|) were ~2-fold greater relative to controls, indicating an overall hypercoagulable tendency. These parameters were related to fibrinogen concentration, and were decreased at 1W and declined to normal at 1M. In T/P-GA, the endogenous potentials of thrombin and plasmin were greater relative to control at each of three time-points, and measurements at 1W were greater than those Pre-treatment. The ratios of TG and PG relative to control were similar, however, suggesting well-balanced dynamic coagulation and fibrinolysis. In non-responders to IVIG, the |min1| and |min2| measurements were greater than those in responders at 1W and 1M, suggesting that non-responders remained hypercoagulable after primary treatment.

CONCLUSION

The coagulation data observed in KD were consistent with hypercoagulability, although fibrinolytic function appeared to be well-balanced. Comprehensive assays of this nature could provide valuable information on coagulation potential in KD.

Effectiveness of intravenous immunoglobulin alone and intravenous immunoglobulin combined with high-dose aspirin in the acute stage of Kawasaki disease: study protocol for a randomized controlled trial

BACKGROUND

Kawasaki disease (KD) is an acute febrile systemic vasculitis most commonly seen in children under 5 years old. High-dose aspirin is often administered, but the duration of such treatment varies. Many centers reduce the aspirin dose once the patient is afebrile, even before treating said patient with intravenous immunoglobulin (IVIG). However, a randomized controlled trial regarding high-dose aspirin in the acute stage of KD has not previously been carried out.

METHODS/DESIGN

This trial has been designed as a multi-center, prospective, randomized controlled, evaluator-blinded trial with two parallel groups to determine whether IVIG alone as the primary therapy in acute-stage KD is as effective as IVIG combined with high-dose aspirin therapy. The primary endpoint is defined as coronary artery lesion (CAL) formation at 6-8 weeks. Patients meeting the eligibility criteria are randomly assigned (1:1) to a test group (that receives only IVIG) or a standard group (that receives IVIG plus high-dose aspirin). This clinical trial is conducted at three medical centers in Taiwan.

DISCUSSION

Since high-dose aspirin has significant anti-inflammatory and anti-platelet functions, it does not appear to affect disease outcomes. Furthermore, it can decrease hemoglobin levels. Therefore, we have initiated this randomized controlled trial to evaluate the necessity of high-dose aspirin in the acute stage of KD.

TRIAL REGISTRATION

Kawasaki Disease Center, Kaohsiung Chang Gung Memorial Hospital, Taiwan. ClinicalTrials.gov Identifier: NCT02951234. Release Date: November 3, 2016.

Differential protein analysis of serum exosomes post-intravenous immunoglobulin therapy in patients with Kawasaki disease

BACKGROUND

Kawasaki disease, which is characterised by systemic vasculitides accompanied by acute fever, is regularly treated by intravenous immunoglobulin to avoid lesion formation in the coronary artery; however, the mechanism of intravenous immunoglobulin therapy is unclear. Hence, we aimed to analyse the global expression profile of serum exosomal proteins before and after administering intravenous immunoglobulin.

METHODS

Two-dimensional electrophoresis coupled with mass spectrometry analysis was used to identify the differentially expressed proteome of serum exosomes in patients with Kawasaki disease before and after intravenous immunoglobulin therapy.

RESULTS

Our analysis revealed 69 differential protein spots in the Kawasaki disease group with changes larger than 1.5-fold and 59 differential ones in patients after intravenous immunoglobulin therapy compared with the control group. Gene ontology analysis revealed that the acute-phase response disappeared, the functions of the complement system and innate immune response were enhanced, and the antibacterial humoral response pathway of corticosteroids and cardioprotection emerged after administration of intravenous immunoglobulin. Further, we showed that complement C3 and apolipoprotein A-IV levels increased before and decreased after intravenous immunoglobulin therapy and that the insulin-like growth factor-binding protein complex acid labile subunit displayed reverse alteration before and after intravenous immunoglobulin therapy. These observations might be potential indicators of intravenous immunoglobulin function.

CONCLUSIONS

Our results show the differential proteomic profile of serum exosomes of patients with Kawasaki disease before and after intravenous immunoglobulin therapy, such as complement C3, apolipoprotein A-IV, and insulin-like growth factor-binding protein complex acid labile subunit. These results may be useful in the identification of markers for monitoring intravenous immunoglobulin therapy in patients with Kawasaki disease.

Epigenetic hypomethylation and upregulation of matrix metalloproteinase 9 in Kawasaki disease

Background

Kawasaki disease (KD) is a type of febrile coronary vasculitis occurring in children. Some researchers have suggested that changes in genetic signatures, such as matrix metalloproteinases (MMPs), are critical markers for cardiovascular diseases. This study aims to provide a comprehensive survey of global DNA methylation levels and MMP transcripts of KD patients compared to control subjects.

Materials and Methods

For chips studies, we recruited a total of 18 KD patients, prior to receiving intravenous immunoglobulin (IVIG) and at least 3 weeks after IVIG treatment, as well as 18 healthy and 18 febrile control subjects. We applied Illumina HumanMethylation450 BeadChip and Affymetrix GeneChip® Human Transcriptome Array 2.0 to evaluate their CpG markers and expression levels, respectively. Then we used a separate cohort to carry out real-time quantitative PCR validations of mRNA levels.

Results

The expressions of mRNA levels of MMP-8, -9, and -25 were significantly upregulated in KD patients compared to the healthy and febrile controls. Once KD patients underwent IVIG treatment, these MMPs considerably decreased. In particular, the methylation status of CpG sites of MMP-9 indicated a significant opposite tendency between both stages of not only the KD samples but also the controls. We also observed the mRNA level of MMP-9 to be higher in KD patients with coronary arterial lesion formation.

Conclusion

This study is the first to report epigenetic hypomethylation, an increased MMP-9 transcript, and the upregulation of MMP-9 in KD patients who had formed coronary arterial lesions.

Sets of serum exosomal microRNAs as candidate diagnostic biomarkers for Kawasaki disease

Although Kawasaki disease is the main cause of acquired heart disease in children, no diagnostic biomarkers are available. We aimed to identify candidate biomarkers for diagnosing Kawasaki disease using serum exosomal microRNAs (miRNAs). Using frozen serum samples from a biobank, high-throughput microarray technologies, two-stage real-time quantitative PCR, and a self-referencing strategy for data normalization, we narrowed down the list of biomarker candidates to a set of 4 miRNAs. We further validated the diagnostic capabilities of the identified miRNAs (namely, CT(miR-1246)-CT(miR-4436b-5p) and CT(miR-197-3p)-CT(miR-671-5p)) in 79 samples from two hospitals. We found that this 4-miRNA set could distinguish KD patients from other febrile patients as well as from healthy individuals in a single pass, with a minimal rate of false positives and negatives. We thus propose, for the first time, that serum exosomal miRNAs represent candidate diagnostic biomarkers for Kawasaki disease. Additionally, we describe an effective strategy of screening for biomarkers of complex diseases even when little mechanistic knowledge is available.

Pathogenetic determinants in Kawasaki disease: the haematological point of view

Kawasaki disease is a multisystemic vasculitis that can result in coronary artery lesions. It predominantly affects young children and is characterized by prolonged fever, diffuse mucosal inflammation, indurative oedema of the hands and feet, a polymorphous skin rash and non‐suppurative lymphadenopathy. Coronary artery involvement is the most important complication of Kawasaki disease and may cause significant coronary stenosis resulting in ischemic heart disease. The introduction of intravenous immunoglobulin decreases the incidence of coronary artery lesions to less than 5%. The etiopathogenesis of this disease remains unclear. Several lines of evidence suggest that an interplay between a microbial infection and a genetic predisposition could take place in the development of the disease. In this review, we summarize the state of the art of pathogenetic mechanisms of Kawasaki disease underscoring the relevance of haematological features as a novel field of investigation.

The human CD5L/AIM-CD36 axis: A novel autophagy inducer in macrophages that modulates inflammatory responses

CD5L (CD5 molecule-like) is a secreted glycoprotein that participates in host response to bacterial infection. CD5L influences the monocyte inflammatory response to the bacterial surface molecules lipopolysaccharide (LPS) and lipoteichoic acid (LTA) by inhibiting TNF secretion. Here we studied the intracellular events that lead to macrophage TNF inhibition by human CD5L. To accomplish this goal, we performed functional analyses with human monocytic THP1 macrophages, as well as with peripheral blood monocytes. Inhibition of phosphatidylinositol 3-kinase (PtdIns3K) reversed the inhibitory effect of CD5L on TNF secretion. Among the various PtdIns3K isoforms, our results indicated that CD5L activates PtdIns3K (whose catalytic subunit is termed PIK3C3), a key modulator involved in autophagy. Further analysis revealed a concomitant enhancement of autophagy markers such as cellular LC3-II content, increased LC3 puncta, as well as LC3-LysoTracker Red colocalization. Moreover, electron microscopy showed an increased presence of cytosolic autophagosomes in THP1 macrophages overexpressing CD5L. Besides preventing TNF secretion, CD5L also inhibited IL1B and enhanced IL10 secretion. This macrophage anti-inflammatory pattern of CD5L was reverted upon silencing of autophagy protein ATG7 by siRNA transfection. Additional siRNA experiments in THP1 macrophages indicated that the induction of autophagy mechanisms by CD5L was achieved through cell-surface scavenger receptor CD36, a multiligand receptor expressed in a wide variety of cell types. Our data represent the first evidence that CD36 is involved in autophagy and point to a significant contribution of the CD5L-CD36 axis to the induction of macrophage autophagy.

Plasma biomarkers for neuronal ceroid lipofuscinosis

The neuronal ceroid lipofuscinoses (NCLs) are a group of neurodegenerative genetic diseases that primarily affect children and have no known cure. A unified clinical rating scale for the juvenile form of NCL has been developed, although it has not been validated in other subtypes and does not give a true measure of the pathophysiological changes occurring during disease progression. In the present study, we have identified candidate biomarkers in blood plasma of NCL disease using multiple proteomic approaches, with the aim of developing a panel of biomarkers that could serve as a metric for therapeutic response. Candidate biomarkers were identified as proteins with levels that significantly differed between patients and controls in both sample sets. The seven candidates identified have previously been associated with neurodegenerative and inflammatory diseases. Multiplex immunoassay based testing was the most efficient and effective evaluation technique and could be employed on a broad scale to track patient response to treatment.

Novel data-mining approach identifies biomarkers for diagnosis of Kawasaki disease

BACKGROUND

As Kawasaki disease (KD) shares many clinical features with other more common febrile illnesses and misdiagnosis, leading to a delay in treatment, increases the risk of coronary artery damage, a diagnostic test for KD is urgently needed. We sought to develop a panel of biomarkers that could distinguish between acute KD patients and febrile controls (FC) with sufficient accuracy to be clinically useful.

METHODS

Plasma samples were collected from three independent cohorts of FC and acute KD patients who met the American Heart Association definition for KD and presented within the first 10 d of fever. The levels of 88 biomarkers associated with inflammation were assessed by Luminex bead technology. Unsupervised clustering followed by supervised clustering using a Random Forest model was used to find a panel of candidate biomarkers.

RESULTS

A panel of biomarkers commonly available in the hospital laboratory (absolute neutrophil count, erythrocyte sedimentation rate, alanine aminotransferase, γ-glutamyl transferase, concentrations of α-1-antitrypsin, C-reactive protein, and fibrinogen, and platelet count) accurately diagnosed 81-96% of KD patients in a series of three independent cohorts.

CONCLUSION

After prospective validation, this eight-biomarker panel may improve the recognition of KD.

Transition from identity to bioactivity-guided proteomics for biomarker discovery with focus on the PF2D platform

Proteomic strategies provide a valuable tool kit to identify proteins involved in diseases. With recent progress in MS technology, high throughput proteomics has accelerated protein identification for potential biomarkers. Numerous biomarker candidates have been identified in several diseases, and many are common among pathologies. An overall strategy that could complement and strengthen the search for biomarkers is combining protein identity with biological outcomes. This review describes an emerging framework of bridging bioactivity to protein identity, exploring the possibility that some biomarkers will have a mechanistic role in the disease process. A review of pulmonary, cardiovascular, and CNS biomarkers will be discussed to demonstrate the utility of combining bioactivity with identification as a means to not only find meaningful biomarkers, but also to uncover functional mediators of disease.

AIM/CD5L: a key protein in the control of immune homeostasis and inflammatory disease

CD5L, a soluble protein belonging to the SRCR superfamily, is expressed mostly by macrophages in lymphoid and inflamed tissues. The expression of this protein is transcriptionally controlled by LXRs, members of the nuclear receptor family that play major roles in lipid homeostasis. Research undertaken over the last decade has uncovered critical roles of CD5L as a PRR of bacterial and fungal components and in the control of key mechanisms in inflammatory responses, with involvement in processes, such as infection, atherosclerosis, and cancer. In this review, we summarize the current knowledge of CD5L, its roles at the intersection between lipid homeostasis and immune response, and its potential use as a diagnostic biomarker in a variety of diseases, such as TB and liver cirrhosis.

Persistent endothelial damage after intravenous immunoglobulin therapy in Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is an acute systemic vasculitis of unknown etiology. Although endothelial cell damage associated with vasculitis might lead to the hypercoagulability that is involved in coronary artery disease, the changes in coagulation after intravenous immunoglobulin therapy (IVIG) have not been well investigated in KD. The aims of this study were to address the changes in coagulation before and after IVIG in KD, and to further elucidate the coagulation-inflammation axis, with special attention to endothelial damage.

METHODS

We retrospectively collected the laboratory data before and after IVIG in 26 pediatric KD patients treated at the Nara Prefecture Western Medical Center between May 2010 and April 2012. Prothrombin time (PT), activated partial thromboplastin time (APTT) and levels of fibrin/fibrinogen degradation products (FDP) and D-dimer were assessed as coagulation markers. Fibrinogen, ferritin, serum amyloid A, procalcitonin and urine β2 microglobulin were assessed as inflammation markers. Thrombomodulin, antithrombin, factor VIII activity (FVIII:C), and von Willebrand factor antigen (VWF:Ag) were used to assess endothelial damage.

RESULTS

Prolonged PT and APTT before IVIG were significantly shortened after IVIG, and elevated levels of FDP and D-dimer were significantly decreased. Elevated levels of inflammation markers had decreased significantly after IVIG, but levels of FVIII:C and VWF:Ag remained high, even after IVIG.

CONCLUSIONS

Ameliorated inflammation by IVIG might improve the hypercoagulable state. Nevertheless, our results suggest that endothelial damage might be prolonged in IVIG-treated patients. Control of endothelial damage in KD is critical.

Genetic variants of CD209 associated with Kawasaki disease susceptibility

BACKGROUND

Kawasaki disease (KD) is a systemic vasculitis with unknown etiology mainly affecting children in Asian countries. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN, CD209) in humans was showed to trigger an anti-inflammatory cascade and associated with KD susceptibility. This study was conducted to investigate the association between genetic polymorphisms of CD209 and the risk KD.

METHODS

A total of 948 subjects (381 KD and 567 controls) were recruited. Nine tagging SNPs (rs8112310, rs4804800, rs11465421, rs1544766, rs4804801, rs2287886, rs735239, rs735240, rs4804804) were selected for TaqMan allelic discrimination assay. Clinical phenotypes, coronary artery lesions (CAL) and intravenous immunoglobulin (IVIG) treatment outcomes were collected for analysis.

RESULTS

Significant associations were found between CD209 polymorphisms (rs4804800, rs2287886, rs735240) and the risk of KD. Haplotype analysis for CD209 polymorphisms showed that A/A/G haplotype (P = 0.0002, OR = 1.61) and G/A/G haplotype (P = 0.0365, OR = 1.52) had higher risk of KD as compared with G/G/A haplotype in rs2287886/rs735239/rs735240 pairwise allele analysis. There were no significant association in KD with regards to CAL formation and IVIG treatment responses.

CONCLUSION

CD209 polymorphisms were responsible for the susceptibility of KD, but not CAL formation and IVIG treatment responsiveness.

Exosomal miRNAs as potential biomarkers of cardiovascular risk in children

Intercellular interactions are essential for basic cellular activities and errors in either receiving or transferring these signals have shown to cause pathological conditions. These signals are not only regulated by membrane surface molecules but also by soluble secreted proteins, thereby allowing for an exquisite coordination of cell functions. Exosomes are released by cells upon fusion of multivesicular bodies (MVB) with the plasma membrane. Their envelope reflects their cellular origin and their surface and internal contents include important signaling components. Exosomes contain a wide variety of proteins, lipids, RNAs, non-transcribed RNAs, miRNAs and small RNAs that are representative to their cellular origin and shuttle from donor cells to recipient cells. The exosome formation cargo content and delivery is of immense biological interest because exosomes are believed to play major roles in various pathological conditions, and therefore provide unique opportunities for biomarker discovery and development of non-invasive diagnostics when examined in biological fluids such as urine and blood plasma. For example, circulating miRNAs in exosomes have been applied as functional biomarkers for diagnosis and outcomes prediction, while synthetic miRNAs in polymer-based nanoparticles are applicable for therapeutics. This review provides insights into the composition and functional properties of exosomes, and focuses on their potential value as diagnostic markers in the context of cardiovascular disease risk estimates in children who suffer from conditions associated with heightened prevalence of adverse cardiovascular disease, namely obesity and sleep-disordered-breathing.

Monitoring of the serum proteome in Kawasaki disease patients before and after immunoglobulin therapy

Kawasaki disease (KD) is a systemic vasculitis that mainly affects children younger than 5 years. The causal pathogen is unknown, therefore specific diagnostic biomarkers and therapy are unavailable. High-dose intravenous immunoglobulin (IVIG) is considered as the most effective therapy to reduce the prevalence of coronary artery lesion (CAL) in KD; however, it has side effects. This study aimed to (1) determine whether IVIG therapy is effective at the molecular level; (2) provide the first serum proteomic profile of KD under IVIG therapy; and (3) screen for monitoring biomarker candidates. We extracted serum proteins from samples of healthy individuals and from KD patients before and after IVIG therapy, and employed two-dimensional electrophoresis and MALDI-TOF/TOF mass spectrometry to identify differentially expressed proteins. The identifications were validated by Western blotting. We identified 29 differentially expressed proteins in KD patients and found that IVIG therapy restored most of these proteins to near-normal levels. Tracing the protein levels of single patients before and after IVIG therapy showed that the proteins, especially Transthyretin (TTR), are potential markers for therapeutic monitoring. Functional analyses of these proteins by PANTHER and String suggested that the key influence of KD lay in the immune system, which was targeted by IVIG.

The macrophage soluble receptor AIM/Api6/CD5L displays a broad pathogen recognition spectrum and is involved in early response to microbial aggression

Apoptosis inhibitor of macrophages (AIMs), a homologue of human Spα, is a mouse soluble member of the scavenger receptor cysteine-rich superfamily (SRCR-SF). This family integrates a group of proteins expressed by innate and adaptive immune cells for which no unifying function has yet been described. Pleiotropic functions have been ascribed to AIM, from viability support in lymphocytes during thymic selection to lipid metabolism and anti-inflammatory effects in autoimmune pathologies. In the present report, the pathogen binding properties of AIM have been explored. By using a recombinant form of AIM (rAIM) expressed in mammalian cells, it is shown that this protein is able to bind and aggregate Gram-positive and Gram-negative bacteria, as well as pathogenic and saprophytic fungal species. Importantly, endogenous AIM from mouse serum also binds to microorganisms and secretion of AIM was rapidly induced in mouse spleen macrophages following exposure to conserved microbial cell wall components. Cytokine release induced by well-known bacterial and fungal Toll-like receptor (TLR) ligands on mouse splenocytes was also inhibited in the presence of rAIM. Furthermore, mouse models of pathogen-associated molecular patterns (PAMPs)-induced septic shock of bacterial and fungal origin showed that serum AIM levels changed in a time-dependent manner. Altogether, these data suggest that AIM plays a general homeostatic role by supporting innate humoral defense during pathogen aggression.

Comparative Proteomics of Sera From HCC Patients With Different Origins

BACKGROUND

Hepatocellular carcinoma (HCC), a major fatal cancer worldwide, is induced by different etiological factors in the liver.

OBJECTIVES

To gain insight into serum protein profiling of HCC with different etiologies.

PATIENTS AND METHODS

We subjected the sera of HBV-HCC, HCV-HCC, non-B non-C-HCC patients, and healthy volunteers to two-dimensional gel electrophoresis (2-DE) and liquid chromatography tandem mass spectrometry (LC-MS/MS).

RESULTS

We found 30 differentially expressed protein spots (≥ 1.5 fold P < 0.05) between these two analyses; of them 17 protein spots corresponding to 8 proteins were identified by MS. Transthyretin, leucine rich α-2-glycoprotein, and ficolin 3 were differentially expressed between HBV-related HCC and non-B non-C-HCC sera. Moreover, haptoglobin α-2 isoforms were decreased in HCV-HCC compared to non-B non-CHCC.

CONCLUSIONS

Serum proteome analyses of HCC with different origins showed a differential protein pattern, presumably related to different hepatopathogenesis in liver induced by different agents. Further studies are required to clarify the importance of identified proteins for early diagnosis of HCC with different origins.

The scavenger protein apoptosis inhibitor of macrophages (AIM) potentiates the antimicrobial response against Mycobacterium tuberculosis by enhancing autophagy

Apoptosis inhibitor of macrophages (AIM), a scavenger protein secreted by tissue macrophages, is transcriptionally regulated by the nuclear receptor Liver X Receptor (LXR) and Retinoid X Receptor (RXR) heterodimer. Given that LXR exerts a protective immune response against M. tuberculosis, here we analyzed whether AIM is involved in this response. In an experimental murine model of tuberculosis, AIM serum levels peaked dramatically early after infection with M. tuberculosis, providing an in vivo biological link to the disease. We therefore studied the participation of AIM in macrophage response to M. tuberculosis in vitro. For this purpose, we used the H37Rv strain to infect THP-1 macrophages transfected to stably express AIM, thereby increasing infected macrophage survival. Furthermore, the expression of this protein enlarged foam cell formation by enhancing intracellular lipid content. Phagocytosis assays with FITC-labeled M. tuberculosis bacilli indicated that this protein was not involved in bacterial uptake; however, AIM expression decreased the number of intracellular cfus by up to 70% in bacterial killing assays, suggesting that AIM enhances macrophage mycobactericidal activity. Accordingly, M. tuberculosis-infected AIM-expressing cells upregulated the production of reactive oxygen species. Moreover, real-time PCR analysis showed increased mRNA levels of the antimicrobial peptides cathelicidin and defensin 4B. These increases were concomitant with greater cellular concentrations of the autophagy-related molecules Beclin 1 and LC3II, as well as enhanced acidification of mycobacterial phagosomes and LC3 co-localization. In summary, our data support the notion that AIM contributes to key macrophage responses to M. tuberculosis.

A replication study for association of ITPKC and CASP3 two-locus analysis in IVIG unresponsiveness and coronary artery lesion in Kawasaki disease

Single-nucleotide polymorphisms (SNPs) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC, rs28493229) and caspase-3 (CASP3, rs113420705) are associated with susceptibility to KD in Japanese and Taiwanese populations. This study was conducted to investigate the involvement of these 2 SNPs in the risk for intravenous immunoglobulin (IVIG) resistance and coronary artery lesion (CAL) in Taiwanese population. A total of 340 KD patients were subjected to assess by the identification of 2-locus genes model. A combinatorial association between ITPKC (rs28493229) and CASP3 (rs113420705) was found in CAL formation (P = 0.0227, OR: 3.06). KD patients with high-risk genotype had a trend of overrepresentation in IVIG resistance compared with individual SNPs. Our findings suggest the existence of genetic factors affecting patients’ risk for CAL formation and IVIG responsiveness in a Taiwanese population.

Plasma clusterin concentrations may predict resistance to intravenous immunoglobulin in patients with Kawasaki disease

Kawasaki disease (KD) is an acute febrile vasculitic syndrome of early childhood often complicated by coronary artery lesion that drastically reduces the quality of life. The study aimed to identify a reliable marker for predicting nonresponsiveness to the first course of intravenous immunoglobulin (IVIG) in KD patients. A total of 63 patients with KD were enrolled in the study (IVIG response, 58; IVIG resistance, 5). Plasma samples were collected before and after IVIG infusion for measurement of biomarkers. Patients' clinical characteristics and laboratory data were also analyzed. A receiver operating characteristic curve was generated to identify a cut-off value for predicting IVIG resistance. Among the biomarkers, the difference in plasma clusterin concentrations before and after IVIG infusion (CLUSTER 12) was significantly related to IVIG resistance (P = 0.040; 95% confidence interval (CI): −25.8% to −6.0%). Using a CLUSTER 12 cut-off value of <8.52 mg/L, the odds ratio for IVIG resistance was 11.467 (95% CI: 1.186 to 110.853). Patients with plasma CLUSTER 12 concentrations >8.52 mg/L had a much higher risk of IVIG resistance than those with CLUSTER 12 concentrations <8.52 mg/L. Plasma clusterin concentration shows promise as a candidate biomarker for predicting IVIG resistance in patients with KD.

Differentially Expressed Proteins in Chronic Active Hepatitis, Cirrhosis, and HCC Related to HCV Infection in Comparison With HBV Infection: A proteomics study

BACKGROUND

Hepatocellular carcinoma is a highly progressive cancer in the case of late diagnosis which is frequently associated with HBV and HCV viral infections.

OBJECTIVES

To identify differentially expressed serum proteins among three main stages of HCV infection and healthy individuals, and their comparisons with sera from patients with the same stage of HBV infection.

PATIENTS AND METHODS

Two-dimensional polyacrylamide gel electrophoresis combined with liquid chromatography-tandem mass spectrometry was performed on 47 sera from healthy volunteers, those with chronic active hepatitis, cirrhosis and HCC patients associated with HBV and HCV infections.

RESULTS

Among these, 62 spots were differentially expressed (≥ 1.5 fold; P < 0.05), of which 42 spots that corresponded to 15 proteins were identified by liquid chromatography-tandem mass spectrometry. CD5-like antigen (CD5L) was differentially expressed between cirrhosis and HCC patients with HCV infection. Leucine-rich α2-glycoprotein (LRG) and haptoglobin (HP) α2 isoforms differed in the HCC that was associated with either HCV or HBV infections.

CONCLUSIONS

CD5L might be a useful biomarker for early diagnosis of HCC in HCV cirrhotic patients. LRG and HP α2 isoforms could be potential markers for distinguishing viral HCC. Our results also further support the presence of varying molecules involved in hepatocarcinogenesis in HBV when compared with HCV infection.

Can a systems biology approach unlock the mysteries of Kawasaki disease?

Kawasaki disease (KD) is a systemic inflammatory illness of childhood that particularly affects the coronary arteries. It can lead to coronary artery aneurysms, myocardial infarction, and sudden death. Clinical and epidemiologic data support an infectious cause, and the etiology remains unknown, but recent data support infection with a 'new' virus. Genetic factors influence KD susceptibility; the incidence is 10-fold higher in children of Asian when compared with Caucasian ethnicity. Recent research has identified genes affecting immune response that are associated with KD susceptibility and outcome. A re-examination of the pathologic features of KD has yielded a three process model of KD vasculopathy, providing a framework for understanding the KD arterial immune response and the damage it inflicts and for identifying new therapeutic targets for KD patients with coronary artery abnormalities. The researcher is faced with many challenges in determining the pathogenesis of KD. A systems biology approach incorporating genomics, proteomics, transcriptomics, and microbial bioinformatics analysis of high-throughput sequence data from KD tissues could provide the keys to unlocking the mysteries of this potentially fatal illness of childhood.

Modification of N-glycosylation modulates the secretion and lipolytic function of apoptosis inhibitor of macrophage (AIM)

The mouse macrophage-derived apoptosis inhibitor of macrophage (AIM), which is incorporated into adipocytes and induces lipolysis by suppressing fatty acid synthase (FAS) activity, possesses three potential N-glycosylation sites. Inactivation of N-glycosylation sites revealed that mouse AIM contains two N-glycans in the first and second scavenger receptor cysteine-rich domains, and that depletion of N-glycans decreased AIM secretion from producing cells. Interestingly, the lack of N-glycans increased AIM lipolytic activity through enhancing AIM incorporation into adipocytes. Although human AIM contains no N-glycan, attachment of N-glycans increased AIM secretion. Thus, the N-glycosylation plays important roles in the secretion and lipolytic function of AIM.

Intrinsic subtype-associated changes in the plasma proteome in breast cancer

Breast cancers are classified into five intrinsic subtypes: Luminal subtype A, Luminal subtype B, HER2+, Basal, and Normal-like. In this study, we compared the plasma proteome of patients with Luminal A, Luminal B, HER2+, and Basal subtype with plasma from healthy individuals. Protein changes were considered significant if q-value (false discovery rate) was less than 5%. The highest number of changes in the plasma proteome was observed in patients with Luminal type B followed by Basal type breast cancers. The plasma proteome of Luminal A and HER2+ breast cancer patients did not differ significantly from healthy individuals. In Basal breast cancer, a significant number of plasma proteins were downregulated compared with healthy individuals. Acute phase-response proteins α-glycoprotein orosomucoid 1 and serum amyloid protein P were specifically upregulated in the plasma of Luminal B breast cancer patients, suggesting prevalence of low-grade inflammation. Proteins involved in immune response and free radical scavenging were downregulated in the plasma of Luminal B patients, which is in agreement with defective immune system observed in cancer patients. These results reveal intrinsic subtype specific changes in the plasma proteome that may influence tumor progression as well as the systemic effects of cancer.

CD40 Gene polymorphisms associated with susceptibility and coronary artery lesions of Kawasaki disease in the Taiwanese population

BACKGROUND

Kawasaki disease (KD) is characterized by systemic vasculitis of unknown etiology. Our previous studies showed expression of CD40 ligand on CD4+ T cells correlated to the coronary artery lesion (CAL) and disease progress in KD. Other studies from Japan suggested the role of CD40L in the pathogenesis of CAL, and this might help explain the excessive number of males affected with KD but cannot be reproduced by Taiwanese population. This study was conducted to investigate the CD40 polymorphism in KD and CAL formation.

METHODS

A total of 950 subjects (381 KD patients and 569 controls) were investigated to identify 2 tagging single-nucleotide polymorphisms (tSNPs) of CD40 (rs4810485 and rs1535045) by using the TaqMan allelic discrimination assay.

RESULTS

A significant association was noted with regards to CD40 tSNPs (rs1535045) between controls and KD patients (P = 0.0405, dominant model). In KD patients, polymorphisms of CD40 (rs4810485) showed significant association with CAL formation (P = 0.0436, recessive model). Haplotype analysis did not yield more significant results between polymorphisms of CD40 and susceptibility/disease activity of KD.

CONCLUSIONS

This study showed for the first time that polymorphisms of CD40 are associated with susceptibility to KD and CAL formation, in the Taiwanese population.

DC-SIGN (CD209) promoter -336 A/G (rs4804803) polymorphism associated with susceptibility of Kawasaki disease

Kawasaki disease (KD) is characterized by systemic vasculitis of unknown etiology. High-dose intravenous immunoglobulin (IVIG) is the most effective therapy for KD to reduce the prevalence of coronary artery lesion (CAL) formation. Recently, the α2, 6 sialylated IgG was reported to interact with a lectin receptor, specific intracellular adhesion molecule-3 grabbing nonintegrin homolog-related 1 (SIGN-R1) in mice and dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN) in human, and to trigger an anti-inflammatory cascade. This study was conducted to investigate whether the polymorphism of DC-SIGN (CD209) promoter −336 A/G (rs4804803) is responsible for susceptibility and CAL formation in KD patients using Custom TaqMan SNP Genotyping Assays. A total of 521 subjects (278 KD patients and 243 controls) were investigated to identify an SNP of rs4804803, and they were studied and showed a significant association between the genotypes and allele frequency of rs4804803 in control subjects and KD patients (P = 0.004 under the dominant model). However, the promoter variant of DC-SIGN gene was not associated with the occurrence of IVIG resistance, CAL formation in KD. The G allele of DC-SIGN promoter −336 (rs4804803) is a risk allele in the development of KD.

Kawasaki disease: an update on diagnosis and treatment

Kawasaki disease (KD) is an acute multi-system vasculitis syndrome of unknown etiology occurring mostly in infants and children younger than 5 years of age. In developed countries, it is the leading cause of acquired heart disease in children. However, KD remains a mysterious disease. Some viruses potentially causing the condition have been isolated, but the results have not been able to be reproduced. This article reviews and summarizes different aspects of KD and provides updated information on diagnosis and treatment. The supplementary criteria for incomplete presentation of KD patients suggested by the American Heart Association, treatment (including tumor necrosis factor-alpha antagonist, methylprednisolone pulse therapy, statins, plasma exchange, and cytotoxic agents) for those with intravenous immunoglobulin treatment failure, and other experiences are also included in this review.

Plasma proteomic analysis in obese and overweight prepubertal children

BACKGROUND

Childhood obesity represents one of the most challenging health problems of our century and is associated with significant morbidity and mortality in adult life. Proteomics is a large-scale analysis of proteins, which provides, information on protein expression levels, post-translational modifications, subcellular localization and interactions.

OBJECTIVE

To investigate whether obesity in childhood is associated with alterations in plasma protein expression profiles.

METHODS

Plasma samples from 10 obese [age: 10·75 ± 0·16 year; body mass index (BMI): 27·50 ± 0·69 kg m(-2) ], 10 overweight (age: 10·54 ± 0·1 year; BMI: 21·88 ± 0·28 kg m(-2) ) and 10 normal-weight (age: 10·89 ± 0·19 year; BMI: 18·34 ± 0·42kg m(-2) ) prepubertal boys were subjected to protein fractionation and analysed by two-dimensional electrophoresis, followed by protein identification using matrix-assisted laser desorption time-of-flight mass spectrometry. Fasting plasma glucose and serum insulin, lipid and apolipopoprotein concentrations were determined in all subjects.

RESULTS

The expression of apolipoprotein (Apo) A-I (ApoA-I) was significantly lower in obese and overweight children compared with children of normal BMI (P < 0·05). The expression of ApoE was significantly lower in overweight compared with normal-weight children (P < 0·05), while that of ApoA-IV was significantly higher in obese children compared with their normal counterparts (P < 0·01). Serum ApoA-I concentrations were significantly lower in obese (147 ± 4·27mg dL(-1) ) and overweight (145·5 ± 9·65mg dL(-1) ) than in normal-weight (157 ± 8·77mg dL(-1) ; P = 0·036) children.

CONCLUSIONS

Obese and overweight prepubertal children demonstrated prominent alterations in the expression of plasma apolipoproteins compared with their normal counterparts. Low ApoA-I plasma expression levels and serum concentrations in obesity might be present in childhood before any significant alterations in total or high-density lipoprotein-cholesterol concentrations are documented. We recommend that serum ApoA-I concentrations are determined in all overweight and obese children.

Polymorphisms of transforming growth factor-β signaling pathway and Kawasaki disease in the Taiwanese population

Kawasaki disease (KD) is a systemic vasculitis associated with cardiovascular symptom. A previous study in the European descent has indicated that genetic variants of the transforming growth factor-β (TGF-β) pathway are involved in the KD susceptibility and clinical status. This study was conducted to investigate if polymorphisms in TGF-β signaling pathway are associated with KD susceptibility, and the coronary artery lesion formation. A total of 950 subjects (381 KD patients and 569 controls) were investigated to identify 12 single-nucleotide polymorphisms in the TGF-β signaling pathway (rs2796817, rs10482751, rs2027567, rs12029576, rs11466480, rs4776338, rs12901071, rs7162912, rs1438386, rs6494633, rs12910698 and rs4776339) by using TaqMan Allelic Discrimination assay. Our results indicated that rs1438386 in the SMAD3 is significantly associated with the susceptibility of KD. Additionally, both haplotypes of TGFβ2 and SMAD3 were also associated with the risk of KD. This study showed that genetic polymorphisms in TGF-β signaling pathway are associated with KD susceptibility, but not coronary artery lesions formation, or intravenous immunoglobulin treatment response in the Taiwanese population.

Genetic polymorphisms in Kawasaki disease

Kawasaki disease (KD) is an acute febrile systemic vasculitis, and the cause of KD is not well understood. It is likely due to multiple interactions between genes and environmental factors. The development of genetic association and genome-wide association studies (GWAS) has opened an avenue to better understanding the molecular mechanisms underlying KD. A novel ITPKC signaling pathway was recently found to be responsible for the susceptibility to KD. Furthermore, the GWAS demonstrated the functionally related susceptibility loci for KD in the Caucasian population. In the last decade, the identification of several genomic regions linked to the pathogenesis of KD has made a major breakthrough in understanding the genetics of KD. This review will focus on genetic polymorphisms associated with KD and describe some of the possible clinical implications and molecular mechanisms that can be used to explain how genetic variants regulate the pathogenesis in KD.

Plasma profiles in active systemic juvenile idiopathic arthritis: Biomarkers and biological implications

Systemic juvenile idiopathic arthritis (SJIA) is a chronic arthritis of children characterized by a combination of arthritis and systemic inflammation. There is usually non-specific laboratory evidence of inflammation at diagnosis but no diagnostic test. Normalized volumes from 89/889 2-D protein spots representing 26 proteins revealed a plasma pattern that distinguishes SJIA flare from quiescence. Highly discriminating spots derived from 15 proteins constitute a robust SJIA flare signature and show specificity for SJIA flare in comparison to active polyarticular juvenile idiopathic arthritis or acute febrile illness. We used 7 available ELISA assays, including one to the complex of S100A8/S100A9, to measure levels of 8 of the15 proteins. Validating our DIGE results, this ELISA panel correctly classified independent SJIA flare samples, and distinguished them from acute febrile illness. Notably, data using the panel suggest its ability to improve on erythrocyte sedimentation rate or C-reactive protein or S100A8/S100A9, either alone or in combination in SJIA F/Q discriminations. Our results also support the panel's potential clinical utility as a predictor of incipient flare (within 9 wk) in SJIA subjects with clinically inactive disease. Pathway analyses of the 15 proteins in the SJIA flare versus quiescence signature corroborate growing evidence for a key role for IL-1 at disease flare.

Plasma clusterin levels in predicting the occurrence of coronary artery lesions in patients with Kawasaki disease

Kawasaki disease (KD) is the leading cause of acquired heart disease during childhood in the developed countries. Coronary artery lesions (CAL) are the major complications of KD. A unique proteomic profiling with increased or decreased fibrinogen, alpha-1-antitrypsin, clusterin, and immunoglobulin free light chains were noted in KD in our previous study. The purpose of this study was to evaluate relations between these biomarkers and CAL in KD and to establish within the markers the appropriate cut-off value with which to predict the occurrence of CAL. A total of 47 KD patients were enrolled, including 14 with CAL and 33 without CAL. Plasma samples from patients with KD before intravenous immunoglobulin administration were indicated for measurement of these biomarkers. A potential relation among CAL, clinical characteristics, and these biomarkers was investigated, and a receiver operating characteristic curve was used to identify a cut-off value of the significant marker that best predicated the occurrence of CAL. Among these biomarkers, only plasma clusterin level was associated with the occurrence of CAL. Using a cut-off value of clusterin <12.0 mg/l, the relative risk for CAL was 4.53-fold (95% confidence interval [CI] 1.060-19.347%, P = 0.014). Results from this study suggest that plasma clusterin level <12.0 mg/l in KD is significantly associated with the occurrence of CAL. Results from this study provide a potential biomarker of KD that may help predict the occurrence of CAL.