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.

MicroRNA expression profile in exosome discriminates extremely severe infections from mild infections for hand, foot and mouth disease.

BACKGROUND: Changes of miRNAs in exosome have been reported in different disease diagnosis and provided as potential biomarkers. In this study, we compared microRNA profile in exosomes in 5 MHFMD and 5 ESHFMD as well as in 5 healthy children. METHODS: Different expression of miRNAs in exosomes across all the three groups were screened using miRNA microarray method. Further validated test was conducted through quantitative real-time PCR assays with 54 exosome samples (18 ESHFMD, 18 MHFMD, and 18 healthy control). The judgment accuracy was then estimated by the receiver operating characteristic (ROC) curve analysis; and the specificity and sensitivity were evaluated by the multiple logistic regression analysis. RESULTS: There were 11 different miRNAs in exosomes of MHFMD and ESHFMD compared to healthy children, of which 4 were up-regulated and 7 were down-regulated. Further validation indicated that the 4 significant differentially expressed candidate miRNAs (miR-671-5p, miR-16-5p, miR-150-3p, and miR-4281) in exosome showed the same changes as in the microarray analysis, and the expression level of three miRNAs (miR-671-5p, miR-16-5p, and miR-150-3p) were significantly different between MHFMD or ESHFMD and the healthy controls. The accuracy of the test results were high with the under curve (AUC) value range from 0.79 to 1.00. They also provided a specificity of 72%-100% and a sensitivity of 78%-100%, which possessed ability to discriminate ESHFMD from MHFMD with the AUC value of 0.76-0.82. CONCLUSIONS: This study indicated that the exosomal miRNA from patients with different condition of HFMD express unique miRNA profiles. Exosomal miRNA expression profiles may provide supplemental biomarkers for diagnosing and subtyping HFMD infections.

Proteomic analysis of extremely severe hand, foot and mouth disease infected by enterovirus 71.

BACKGROUND: To clarify the molecular mechanisms that participate in the severe hand, foot and mouth disease (HFMD) infected by Enterovirus 71 and to detect any related protein biomarkers, we performed proteomic analysis of protein extracts from 5 extremely severe HFMD children and 5 healthy children. METHODS: The protein profiles of them were compared using two-dimensional electrophoresis. Differentially expressed proteins were identified using mass spectrometry. Functional classifications of these proteins were based on the PANTHER. The interaction network of the differentially expressed protein was generated with Pathway Studio. RESULTS: A total of 38 differentially expressed proteins were identified. Functional classifications of these proteins indicated a series of altered cellular processes as a consequence of the severe HFMD. These results provided not only new insights into the pathogenesis of severe HFMD, but also implications of potential therapeutic designs. CONCLUSIONS: Our results suggested the possible pathways that could be the potential targets for novel therapy: viral protection, complement system and peroxide elimination.

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.