Downregulation of Th17 cells and the related cytokines with treatment in Kawasaki disease

[Research advances in genetic polymorphisms in Kawasaki disease]

Kawasaki disease (KD) is a systemic inflammatory vascular disorder that predominantly affects children and is the leading cause of acquired heart disease in children. Although the etiology of this disease remains unclear, genome-wide association and genome-wide linkage studies have shown that some susceptible genes and chromosomal regions are associated with the development and progression of KD. With the advancement of high-throughput DNA sequencing techniques, more and more genomic information related to KD is being discovered. Understanding the genes involved in the pathogenesis of KD may provide novel insights into the diagnosis and treatment of KD. By analyzing related articles and summarizing related research advances, this article mainly discusses the T cell activation-enhancing genes that have been confirmed to be closely associated with the development and progression of KD and reveals their association with the pathogenesis of KD and coronary artery lesions.

Intravenous Immunoglobulin: Mechanism of Action in Autoimmune and Inflammatory Conditions

Intravenous immunoglobulin (IVIG) is the mainstay of therapy for humoral immune deficiencies and numerous inflammatory disorders. Although the use of IVIG may be supplanted by several targeted therapies to cytokines, the ability of polyclonal normal IgG to act as an effector molecule as well as a regulatory molecule is a clear example of the polyfunctionality of IVIG. This article will address the mechanism of action of IVIG in a number of important conditions that are otherwise resistant to treatment. In this commentary, we will highlight mechanistic studies that shed light on the action of IVIG. This will be approached by identifying effects that are both common and disease-specific, targeting actions that have been demonstrated on cells and processes that represent both innate and adaptive immune responses.

Interleukin-35 Enhances Regulatory T Cell Function by Potentially Suppressing Their Transdifferentiation into a T Helper 17-Like Phenotype in Kawasaki Disease

Interleukin-35 (IL-35) modulates immune cell activity in inflammation and autoimmune disorders. However, its specific effects on regulatory T cells (Tregs) in Kawasaki disease remain ambiguous. We enrolled 37 patients with Kawasaki disease and 20 healthy controls in this study. The percentages of CD4⁺CD25⁺CD127^dim/- Tregs and CD4⁺IL-17A⁺ T helper 17 (Th17) cells were determined via flow cytometry. Tregs were enriched and stimulated by recombinant IL-35. Immunosuppressive activity of Tregs was via co-culture with autologous CD4⁺CD25^- T cells. Purified Tregs were cultured for Th17 polarization, and the influence of IL-35 on Tregs transdifferentiation into a Th17-like phenotype was determined. The percentage of Tregs was elevated in patients with Kawasaki disease and positively correlated with C-reactive protein levels. There was no significant difference in the percentage of Th17 cells between the two groups. IL-35 stimulation increased the percentage of Tregs in both groups, but decreased the percentage of Tregs Th17 cells in affected patients. IL-35 enhanced the immunosuppressive activity of Tregs in both groups, resulting in decreased cellular proliferation and increased IL-35 subunit mRNA relative levels in co-culture system. IL-35 did not affect the immune checkpoint molecule expression in Tregs, but inhibited the transdifferentiation of Tregs into a Th17-like phenotype in affected patients, indicating by the down-regulations of C-C motif chemokine receptor-4/6 expression, retinoid-related orphan nuclear receptor γt mRNA levels, and IL-17 secretion. IL-35 contributes to the immunosuppressive function of Tregs by inhibiting the cellular proliferation and transdifferentiation of Tregs into a Th17-like phenotype, which may be a protective mechanism against Kawasaki disease.

Risk factors and coronary artery outcomes of coronary artery aneurysms differing in size and emergence time in children with Kawasaki disease

Coronary artery aneurysm (CAA) is a serious cardiac complication arising from Kawasaki disease (KD) and is becoming the leading cause of acquired heart disease in children. The aim of this study was to determine the potential risk factors associated with coronary artery aneurysms (CAAs), which differ in size and emergence time, and track its regression within 3 years of onset. The laboratory data, clinical features, and coronary artery outcomes of patients, who were diagnosed with KD and received treatment from January 2003 to January 2019 were retrospectively analyzed. A total of 484 pediatric patients with KD were examined during the study period. Among them, 130 (26.9%) presented with CAA, including mid- to large-sized CAA in 38 patients (7.9%) and de novo CAA after intravenous immunoglobulin (IVIG) treatment in 22 patients (4.5%). Albumin-to-globin (A/G) ratio was significantly negatively associated with the absolute internal diameter of coronary artery at 1 month of onset and may be used as a predictor of mid- to large-sized CAA development in patients with KD. The area under the receiver operating characteristic curve was 0.637 (95% confidence interval: 0.551–0.724), and a cutoff of 1.32 yielded a sensitivity and specificity of 79 and 49%, respectively, for predicting mid- to large-sized CAA development. De novo CAA after IVIG may lead to an increased risk of developing progressive CAA [13 (59.1%) of 22 vs. 31 (28.7%) of 108; P = 0.006] and had significantly greater changes in both the magnitude of CAA dimension variation and maximum z-score of the coronary arteries at 2 and 4 weeks and then 3 months after onset (P < 0.001). Kaplan–Meier survival analysis revealed that the estimated median time of aneurysm persistence was significantly higher in the progressive CAA group than in the non-progressive CAA group (25 vs. 4 months, P < 0.001), as well as among the three groups of patients (giant CAA > medium-sized CAA > small-sized CAA, P < 0.001). Children with KD who had low A/G ratio were more likely to develop mid- to large-sized CAA. Nevertheless, de novo CAA after IVIG treatment may increase the risk of more severe arterial damage and development of progressive coronary artery damage; and both mid- to large-sized and de novo CAA could dramatically prolong coronary artery normalization time. Thus, aggressive risk modifications should be employed, and close monitoring with frequent echocardiography is needed for this vulnerable patient population.

Diagnostic model based on bioinformatics and machine learning to distinguish Kawasaki disease using multiple datasets

Background

Kawasaki disease (KD), characterized by systemic vasculitis, is the leading cause of acquired heart disease in children. Herein, we developed a diagnostic model, with some prognosis ability, to help distinguish children with KD.

Methods

Gene expression datasets were downloaded from Gene Expression Omnibus (GEO), and gene sets with a potential pathogenic mechanism in KD were identified using differential expressed gene (DEG) screening, pathway enrichment analysis, random forest (RF) screening, and artificial neural network (ANN) construction.

Results

We extracted 2,017 DEGs (1,130 with upregulated and 887 with downregulated expression) from GEO. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that the DEGs were significantly enriched in innate/adaptive immune response-related processes. Subsequently, the results of weighted gene co-expression network analysis and DEG screening were combined and, using RF and ANN, a model with eight genes (VPS9D1, CACNA1E, SH3GLB1, RAB32, ADM, GYG1, PGS1, and HIST2H2AC) was constructed. Classification results of the new model for KD diagnosis showed excellent performance for different datasets, including those of patients with KD, convalescents, and healthy individuals, with area under the curve values of 1, 0.945, and 0.95, respectively.

Conclusions

We used machine learning methods to construct and validate a diagnostic model using multiple bioinformatic datasets, and identified molecules expected to serve as new biomarkers for or therapeutic targets in KD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03557-y.

Exploring the Mechanism of Aspirin in the Treatment of Kawasaki Disease Based on Molecular Docking and Molecular Dynamics

Purpose

The research aims to investigate the mechanism of action of aspirin in the treatment of Kawasaki disease.

Methods

We predicted the targets of aspirin with the help of the Drugbank and PharmMapper databases, the target genes of Kawasaki disease were mined in the GeneCards and Disgenet databases, the intersection targets were processed in the Venny database, and the gene expression differences were observed in the GEO database. The Drugbank and PharmMapper databases were used to predict the target of aspirin, and the target genes of Kawasaki disease were explored in the GeneCards and Disgenet databases, and the Venny was used for intersection processing. We observed the gene expression differences in the GEO database. The disease-core gene target-drug network was established and molecular docking was used for verification. Molecular dynamics simulation verification was carried out to combine the active ingredient and the target with a stable combination. The supercomputer platform was used to measure and analyze the binding free energy, the number of hydrogen bonds, the stability of the protein target at the residue level, the radius of gyration, and the solvent accessible surface area.

Results

Aspirin had 294 gene targets, Kawasaki disease had 416 gene targets, 42 intersecting targets were obtained, we screened 13 core targets by PPI; In the GO analysis, we learned that the biological process of Kawasaki disease involved the positive regulation of chemokine biosynthesis and inflammatory response; pathway enrichment involved PI3K-AKT signaling pathway, tumor necrosis factor signaling pathway, etc. After molecular docking, the data showed that CTSG, ELANE, and FGF1 had the best binding degree to aspirin. Molecular dynamics was used to prove and analyze the binding stability of active ingredients and protein targets, and Aspirin/ELANE combination has the strongest binding energy.

Conclusion

In the treatment of Kawasaki disease, aspirin may regulate inflammatory response and vascular remodeling through CTSG, ELANE, and FGF1.

The Th17 Pathway in Vascular Inflammation: Culprit or Consort?

The involvement of IL-17A in autoimmune and inflammatory diseases has prompted the development of therapeutic strategies to block the Th17 pathway. Promising results came from their use in psoriasis and in ankylosing spondylitis. IL-17A acts on various cell types and has both local and systemic effects. Considering the premature mortality observed during chronic inflammatory diseases, IL-17A action on vascular cells was studied. Both in vitro and in vivo results suggest that this cytokine favors inflammation, coagulation and thrombosis and promotes the occurrence of cardiovascular events. These observations led to study the role of IL-17A in diseases characterized by vascular inflammation, namely allograft rejection and vasculitis. Increased circulating levels of IL-17A and histological staining reveal that the Th17 pathway is involved in the pathogenesis of these diseases. Vasculitis treatment faces challenges while the use of steroids has many side effects. Regarding results obtained in giant cell arteritis with IL-6 inhibitors, a cytokine involved in Th17 differentiation, the use of anti-IL-17 is a promising strategy. However, lessons from rheumatoid arthritis and multiple sclerosis must be learnt before targeting IL-17 in vasculitis, which may be culprit, consort or both of them.

CASP5 and CR1 as potential biomarkers for Kawasaki disease: an Integrated Bioinformatics-Experimental Study

BACKGROUND

Kawasaki disease (KD) is a pediatric inflammatory disorder causes coronary artery complications. The disease overlapping manifestations with a set of symptomatically like diseases such as bacterial and viral infections, juvenile idiopathic arthritis, Henoch-Schönlein purpura, infection of unknown etiology, group-A streptococcal and adenoviral infections, and incomplete KD could lead to misdiagnosis of the disease.

METHODS

In the present study, we applied weighted gene co-expression network analysis (WGCNA) to identify network modules of co-expressed genes in GSE73464 and also, limma package was used to identify the differentially expressed genes (DEGs) in KD expression arrays composed of GSE73464, GSE18606, GSE109351, and GSE68004. By merging the results of WGCNA and limma, we detected hub genes. Then, analyzed the peripheral blood mononuclear cells (PBMCs) of 16 patients and 8 control subjects using Real-Time Polymerase Chain Reaction (RT-PCR) to evaluate the previous results.

RESULTS

We assessed the diagnostic potency of the screened genes by plotting the area under curve (AUC). We finally identified 2 genes CASP5(Caspase 5) and CR1(Complement C3b/C4b Receptor 1) which were shown to potentially discriminate KD from other similar diseases and also from healthy people.

CONCLUSIONS

The results of RT-PCR and AUC confirmed the diagnostic potentials of two suggested biomarkers for KD.

Shaanxi Provincial Diagnosis and Treatment Center of Kawasaki Disease

Kawasaki disease is an acute, self-limited vascuitis that mainly occurs in children under 5 years of age. Intravenous immunoglobulin (IVIG) has become an effective treatment regimen, which can effectively reduce the incidence of cardiovascular complications. However, there has been no consensus or clinical guidelines for the application of IVIG in children with Kawasaki disease till now. This consensus is developed based on the current research progress on the application of IVIG in children with Kawasaki disease in China and overseas, with reference to the diagnosis and treatment guidelines for Kawasaki disease in China and overseas, and the opinions of experts. This consensus provides recommendations on the clinical application strategy of IVIG in children with Kawasaki disease and the prevention and treatment of its adverse reactions. Citation.

Analysis of the Risk Factors in Prognosis of Kawasaki Disease With Coronary Artery Lesions

Kawasaki disease (KD) is one of the most common forms of systemic vasculitis in children. Pathological features include extensive inflammation of small and medium blood vessels throughout the body. The primary complication of KD is coronary artery lesions (CALs). A total of 640 children with KD were admitted to the Department of Pediatric Cardiology at Shengjing Hospital of China Medical University from January 2017 to December 2019. These patients comprised 52 coronary artery aneurysm (CAA) cases and 47 coronary artery dilation (CAD) cases. Echocardiography was performed during the acute KD phase and then at 1, 3, 6, 12, and 24 months after KD onset. Patients were divided into a poor prognosis group (n = 30) and a normal group (n = 69) based on CALs prognosis. Differences in laboratory data, clinical manifestations and coronary artery damage rates were compared between the two groups. Univariate analysis was performed on these data, and an ROC curve was used to analyze the efficacy of each risk factor. Univariate analysis revealed that age (months), number of coronary arteries involved (NACI), IgM, IgA and brain natriuretic peptide (ProBNP) levels were higher in the poor prognosis group compared with the normal group, procalcitonin (PCT) levels in the poor prognosis group were lower than in the normal group (P < 0.05). Conclusion: Age ≥ 18 months, IgM ≥ 1.07g/L, IgA ≥ 0.728g/L and NCAI ≥ 3 were poor prognostic factors of KD children with CALs. These parameters can be used as a reference indicator of early prediction where combined detection might improve the accuracy and sensitivity of prediction. Follow-up should be maintained to monitor changes in the coronary artery by echocardiography.

Efficacy of infliximab in the treatment of Kawasaki disease: A systematic review and meta-analysis

The present study aimed to review the relevant studies in order to determine the efficacy of infliximab (IFX) in the treatment of Kawasaki disease (KD). The relevant studies were retrieved using the PubMed, Cochrane and Embase databases. Key sources in the literature were reviewed; all articles published by July 2019 were considered for inclusion. For each study, odds ratios, mean difference and 95% confidence interval (95% CI) were assessed to evaluate study outcomes. A total of 16 studies involving 429 patients were relevant to the questions of interest of the current meta-analysis. Compared with intravenous immunoglobulin (IVIG), IFX or IFX plus IVIG significantly reduced the incidence of adverse events, including the number of patients with fever, changes in lip and oral cavity and/or cervical lymphadenopathy. The white blood cell (WBC), neutrophil and C-reactive protein (CRP) levels were also reduced in the IFX or IFX plus IVIG group compared with those in the IVIG or polyethylene glycol-treated human immunoglobulin (VGIH) groups. The platelet counts, alanine aminotransferase (ALT) levels and Z-scores were increased in the IFX or IFX plus IVIG groups compared with those in the IVIG or VGIH groups. In the single-arm studies, the incidence of coronary artery aneurysm was 0.150 (95% CI: 0.024, 0.277), the non-response rate was 0.097 (95% CI: 0.056, 0.138), and the incidence of adverse events was 0.156 (95% CI: 0.122, 0.190). IFX not only effectively reduced the incidence of fever, conjunctival injection, changes in lip and oral cavity and cervical lymphadenopathy polymorphous exanthema, but also the WBC, neutrophil, ALT and CRP levels. The platelet levels were increased in patients after the IFX therapy compared with patients in the IVIG or VGIH groups. IFX or IFX plus IVIG exhibited improved clinical efficacy in the treatment of KD compared with that of IVIG or VGIH. However, as a limited number of studies was included in the current study, the findings should be verified further.

Antibodies and Immunity During Kawasaki Disease

The cause of Kawasaki disease (KD), the leading cause of acquired heart disease in children, is currently unknown. Epidemiology studies support that an infectious disease is involved in at least starting the inflammatory cascade set off during KD. Clues from epidemiology support that humoral immunity can have a protective effect. However, the role of the immune system, particularly of B cells and antibodies, in pathogenesis of KD is still unclear. Intravenous immunoglobulin (IVIG) and other therapies targeted at modulating inflammation can prevent development of coronary aneurysms. A number of autoantibody responses have been reported in children with KD and antibodies have been generated from aneurysmal plasma cell infiltrates. Recent reports show that children with KD have similar plasmablast responses as other children with infectious diseases, further supporting an infectious starting point. As ongoing studies are attempting to identify the etiology of KD through study of antibody responses, we sought to review the role of humoral immunity in KD pathogenesis, treatment, and recovery.

Kawasaki Disease and Allergic Diseases

Background: Kawasaki disease (KD) is an inflammatory disorder with an unknown etiology. It is the leading cause of acquired heart disease, which leads to coronary vasculitis among children. Studies of frequent manifestation of allergic diseases in children with KD have been the subject of mounting clinical interest. However, evidence supporting the association between KD and allergies has yet to be systematically reviewed. Methods: In this article, we reviewed current literature regarding the association between KD and allergic diseases. References for this review were identified through searches of PubMed, Cochrane, and Embase through the end of August 2020. Results: The results of the analyses of immune repertoire, clinical, and epidemiological studies have indicated some of the characteristics of infectious disease for KD. Although some allergic disorders, such as asthma, may be exacerbated by viral infections, allergies are typically caused by an allergen that triggers an immune response, with the potential involvement of type 2 inflammation and immune disturbances leading to tissue remodeling in genetically susceptible hosts. The effect of intravenous immunoglobulin is multi-faceted and results in a decrease in activating Fc gamma receptor IIA and an increase in anti-inflammatory eosinophils. The findings from this review demonstrate that children who have suffered from KD are more likely to have allergic rhinitis than the general population and their siblings, a condition that lasts until the age of 17. When followed up as teenagers and adults, children with KD are more likely to develop urticaria. Conclusions: This review supports that allergic diseases, such as allergic rhinitis, have been demonstrated to increase following KD. Therefore, the importance of allergic diseases in patients with KD should be emphasized in long-term care. Interventions that include strategies for managing allergies in children with KD would be beneficial.

Plasma Exchange Downregulates Activated Monocytes and Restores Regulatory T Cells in Kawasaki Disease

In Kawasaki disease (KD), the effect of plasma exchange (PE) on immune cells has not been fully elucidated. Therefore, we examined the changes in the number of CD14⁺ CD16⁺ activated monocytes, regulatory T (T_reg ), and T-helper type 17 (Th17) cells in KD patients treated with PE. The percentage of total monocytes and subclasses of lymphocytes, including CD4⁺ and CD8⁺ T cells, and CD19⁺ B cells, showed no significant difference before and after PE. However, the percentage of CD14⁺ CD16⁺ monocytes in total leukocytes decreased significantly after PE (1.1% ± 1.5% vs. 2.1% ± 2.3%, P < 0.05). Furthermore, while the percentage of Th17 cells in CD4⁺ T cells did not change, the percentage of T_reg cells in CD4⁺ T cells increased significantly after PE (11.1% ± 5.1% vs. 8.0% ± 4.4%, P < 0.05). Therefore, PE downregulates activated monocytes and upregulates T_reg cells toward normal levels and thus attenuates inflammation in KD.

Infliximab regulates monocytes and regulatory T cells in Kawasaki disease

BACKGROUND

The effect of infliximab (IFX) on immune cells has not been fully reported in Kawasaki disease (KD). To investigate the mechanism of IFX in KD, we examined changes in the abundance of CD14⁺ CD16⁺ activated monocytes, regulatory T cells (T_reg ) cells, and T-helper type 17 (Th17) cells following treatment with IFX.

METHODS

We collected peripheral blood from patients with i.v. immunoglobulin (IVIG)-resistant KD and analyzed absolute CD14⁺ CD16⁺ monocyte, T_reg (CD4⁺ CD25⁺ FOXP3⁺ ) and Th17 cell (CD4⁺ IL-17A⁺ ) counts on flow cytometry. We also measured changes in serum soluble interleukin (IL)-2 receptor (IL-2R), IL-6, and tumor necrosis factor (TNF)-α on enzyme-linked immunosorbent assay.

RESULTS

T_reg cells and Th17 cells significantly increased after IFX treatment compared with baseline (126 ± 85 cells/μL vs 62 ± 53 cells/μL, P < 0.01; 100 ± 111 cells/μL vs 28 ± 27 cells/μL, P < 0.05, respectively). In contrast, in a subgroup of patients with CD14⁺ CD16⁺ monocytes above the normal range before IFX, the CD14⁺ CD16⁺ monocytes significantly decreased following IFX treatment (72 ± 51 cells/μL vs 242 ± 156 cells/μL, P < 0.05).. Serum TNF-α did not change, but soluble IL-2R and IL-6 decreased after IFX treatment.

CONCLUSION

IFX could downregulate activated monocytes and upregulate T_reg cells towards the normal range. IFX treatment thus contributes to the process of attenuating inflammation in KD.

Kawasaki disease: guidelines of the Italian Society of Pediatrics, part I - definition, epidemiology, etiopathogenesis, clinical expression and management of the acute phase

The primary purpose of these practical guidelines related to Kawasaki disease (KD) is to contribute to prompt diagnosis and appropriate treatment on the basis of different specialists’ contributions in the field. A set of 40 recommendations is provided, divided in two parts: the first describes the definition of KD, its epidemiology, etiopathogenetic hints, presentation, clinical course and general management, including treatment of the acute phase, through specific 23 recommendations.

Their application is aimed at improving the rate of treatment with intravenous immunoglobulin and the overall potential development of coronary artery abnormalities in KD. Guidelines, however, should not be considered a norm that limits treatment options of pediatricians and practitioners, as treatment modalities other than those recommended may be required as a result of peculiar medical circumstances, patient’s condition, and disease severity or complications.

Serum exosomal miR-328, miR-575, miR-134 and miR-671-5p as potential biomarkers for the diagnosis of Kawasaki disease and the prediction of therapeutic outcomes of intravenous immunoglobulin therapy

The present study was conducted to screen serum exosomal microRNAs (miRNAs) for the early diagnosis of Kawasaki disease (KD) and to investigate their underlying mechanisms by analyzing microarray data under accession numbers GSE60965 [exosomal miRNA, including three pooled serum samples from 5 healthy children, 5 patients with KD and 5 patients with KD following intravenous immunoglobulin (IVIG) therapy] and GSE73577 (mRNA, including peripheral blood mononuclear cell samples from 19 patients with KD prior to and following IVIG treatment) from the Gene Expression Omnibus database. Differentially expressed miRNAs (DE-miRNAs) and genes (DEGs) were identified using the Linear Models for Microarray data method, and the mRNA targets of DE-miRNAs were predicted using the miRWalk 2.0 database. The functions of the target genes were analyzed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). As a result, 65 DE-miRNAs were identified with different expression patterns between the healthy children and patients with KD and between patients with KD and patients with KD following IVIG therapy. The target genes of 15 common DE-miRNAs were predicted. Following overlapping the target genes of DE-miRNAs with 355 DEGs, 28 common genes were identified and further screened to construct a network containing 30 miRNA-mRNA regulatory associations. Of these associations, only miR-328-spectrin α, erythrocytic 1, miR-575-cyclic AMP-responsive element-binding protein 5/b-1,4-galactosyltransferase 5/WD repeat and FYVE domain-containing 3/cystatin-A/C-X-C motif chemokine receptor 1/protein phosphatase 1 regulatory subunit 3B, miR-134-acyl-CoA synthetase long chain family member 1/C-type lectin domain family 1 member A and miR-671-5p-tripartite motif containing 25/leucine rich repeat kinase 2/kinesin family member 1B/leucine rich repeat neuronal 1 were involved in the negative regulation of gene expression. Functional analysis indicated that the identified target genes may be associated with inflammation. Accordingly, serum exosomal miR-328, miR-575, miR-134 and miR-671-5p may act as potential biomarkers for the diagnosis of KD and the prediction of outcomes of the IVIG therapy by influencing the expression of inflammatory genes.

Serum miR-200c and miR-371-5p as the Useful Diagnostic Biomarkers and Therapeutic Targets in Kawasaki Disease

Kawasaki disease (KD) has complexly clinical features and laboratory parameters and there is no definitive biomarker for this disease and the therapy of KD also is complex and uncertain. In this study, 102 KD patients and 80 healthy controls were enrolled in this study and the serum microRNAs were detected by qRT-PCR. The results showed that, compared with KD patients with a good response to high-dose intravenous immunoglobulin (IVIG) therapy, serum miR-200c and miR-371-5p were significantly higher in KD patients with no response to IVIG therapy; compared with KD patients not needing plasma exchange, these two microRNAs were also significantly higher in KD patients needing plasma exchange. In addition, combination of serum miR-200c and miR-371-5p reflected obvious separation between KD patients and healthy controls or between KD patients with no response to IVIG therapy and KD patients with good response to IVIG therapy or KD patients needing plasma exchange and KD patients not needing plasma exchange. Finally, both serum miR-200c and miR-371-5p were also significantly lower in KD under different kinds of therapy. Therefore, serum miR-200c and miR-371-5p have ability as the useful diagnostic biomarkers and therapeutic targets in Kawasaki disease.

Atypical desquamation in a 2.5-year-old boy with Kawasaki disease: A case report

Kawasaki disease (KD) is a vasculitis that mostly affects children under 5 years of age. This article presents a 2.5-year-old boy who presented with 6 days of fever, generalized maculopapular rash, bilateral non-exudative conjunctivitis, cracked lips, right cervical lymphadenopathy, erythematous extremities, and perianal desquamation. Laboratory studies showed leukocytosis and sterile pyuria. Because diagnosis of KD was proved, oral acetylsalicylic acid with the anti-inflammatory dose and intravenous immunoglobulin were started for him. On the seventh day of admission time, he developed desquamation and erythema on the site of his right cervical lymphadenopathy as well as periungual scaling. About three weeks after starting the treatment, scaling of the cervical lymphadenopathy and periungual area stopped. Echocardiography was performed for him three times: at the time of diagnosis, four weeks, and 6 months later and revealed normal coronary arteries. We report this sign, desquamation on the site of cervical lymphadenopathy, as a new finding.

Relationship between IL-27 and coronary arterial lesions in children with Kawasaki disease

Kawasaki disease (KD) arises due to the disorder of the inflammation response and faulty immune regulation. Interleukin-27 (IL-27) is a novel cytokine with both pro-inflammatory and anti-inflammatory effects. This study investigated the relationship between serum levels of IL-27, Interleukin-17A (IL-17A), Interleukin-10 (IL-10), Interleukin-6 (IL-6), Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and coronary artery lesions (CALs) in patients with KD. We obtained blood samples from 81 children with KD before intravenous immunoglobulin (IVIG) therapy. Levels of IL-27, IL-17A, IL-10, IL-6, IL-1β and TNF-α were measured in 251 cases, including 4 groups: the normal control group, NC (n = 90), febrile control, FC (n = 80), KD without coronary arteries (n = 41) and KD with coronary arterial lesions (n = 40). White blood cells counts (WBC), red blood cells counts (RBC), hemoglobin, C-reactive protein (CRP), erythrocyte sedimentation rate and procalcitonin (PCT) were tested in all subjects. Levels of IL-27, IL-10, IL-17A, IL-6, IL-1β and TNF-α were significantly elevated, and RBC and hemoglobin significantly decreased in the group of KD group compared with febrile and control groups. IL-27, IL-6, IL-1β and TNF-α serum levels are even higher in KD children with CALs. There was positive relationship between serum levels of IL-27 and WBC, CRP, PCT, IL-10, IL-17A, IL-6 and TNF-α in children with KD. The up-regulation of IL-27 may be closely linked to up-regulation of systemic pro-inflammatory markers in acute KD. Morover, IL-27 may be involved in the development of CALs in acute KD.

Kawasaki disease: a matter of innate immunity

Kawasaki disease (KD) is an acute systemic vasculitis of childhood that does not have a known cause or aetiology. The epidemiological features (existence of epidemics, community outbreaks and seasonality), unique age distribution and clinical symptoms and signs of KD suggest that the disease is caused by one or more infectious environmental triggers. However, KD is not transmitted person-to-person and does not occur in clusters within households, schools or nurseries. KD is a self-limited illness that is not associated with the production of autoantibodies or the deposition of immune complexes, and it rarely recurs. Regarding the underlying pathophysiology of KD, innate immune activity (the inflammasome) is believed to play a role in the development of KD vasculitis, based on the results of studies with animal models and the clinical and laboratory findings of KD patients. Animal studies have demonstrated that innate immune pathogen-associated molecular patterns (PAMPs) can cause vasculitis independently of acquired immunity and have provided valuable insights regarding the underlying mechanisms of this phenomenon. To validate this concept, we recently searched for KD-specific PAMPs and identified such molecules with high specificity and sensitivity. These molecules have structures similar to those of microbe-associated molecular patterns (MAMPs), as shown by liquid chromatography-tandem mass spectrometry. We propose herein that KD is an innate immune disorder resulting from the exposure of a genetically predisposed individual to microbe-derived innate immune stimulants and that it is not a typical infectious disease.

Kawasaki Disease

Kawasaki disease is an acute, self-limited vasculitis of unknown etiology that occurs predominantly in infants and children. If not treated early with high-dose intravenous immunoglobulin, 1 in 5 children develop coronary artery aneurysms; this risk is reduced 5-fold if intravenous immunoglobulin is administered within 10 days of fever onset. Coronary artery aneurysms evolve dynamically over time, usually reaching a peak dimension by 6 weeks after illness onset. Almost all the morbidity and mortality occur in patients with giant aneurysms. Risk of myocardial infarction from coronary artery thrombosis is greatest in the first 2 years after illness onset. However, stenosis and occlusion progress over years. Indeed, Kawasaki disease is no longer a rare cause of acute coronary syndrome presenting in young adults. Both coronary artery bypass surgery and percutaneous intervention have been used to treat Kawasaki disease patients who develop myocardial ischemia as a consequence of coronary artery aneurysms and stenosis.

Predisposing factors, pathogenesis and therapeutic intervention of Kawasaki disease

Kawasaki disease (KD) is an acute febrile childhood inflammatory disease, associated with coronary artery abnormalities. The disease is believed to result from an aberrant inflammatory response to an infectious trigger in a genetically predisposed individual. KD is associated with an endothelial cell injury as a consequence of T cell activation and cytotoxic effects of various proinflammatory cytokines. Intravenous immunoglobulin (IVIG) infusion and aspirin are the standard treatment of acute KD. However, 10-20% of patients show resistance to IVIG therapy and present higher risk of coronary vasculitis. The relative roles of second IVIG infusion, corticosteroids, calcineurin inhibitors, interleukin-1 antagonists and anti-tumor necrosis factor agents remain uncertain. In this review, we highlight the predisposing factors, pathogenesis and therapeutic intervention of KD, particularly new therapeutics for IVIG-resistant patients.

[Changes in peripheral blood T helper 9 cells and interleukin-9 in children in the acute stage of Kawasaki disease]

OBJECTIVE

To investigate the changes in the expression levels of peripheral blood T helper 9 (Th9) cells and cytokine interleukin-9 (IL-9) in children in the acute stage of Kawasaki disease (KD) and their clinical significance.

METHODS

A total of 45 children in the acute stage of KD who were treated from April 2014 to July 2015 were enrolled, and the children were followed up in the recovery stage. Another 45 healthy children who underwent physical examination were enrolled as the control group. Flow cytometry was used to measure the percentage of peripheral blood Th9 cells, and ELISA was used to measure the serum level of IL-9.

RESULTS

The children in the acute stage of KD showed a significantly higher percentage of Th9 cells and a significantly higher serum level of IL-9 compared with those in the recovery stage and the control group (P<0.05). The percentage of Th9 cells and serum level of IL-9 showed no significant differences between the children in the recovery stage and those in the control group (P>0.05). In the acute stage, the percentage of Th9 cells was positively correlated with the levels of IL-9, C-reactive protein (CRP), procalcitonin (PCT), erythrocyte sedimentation rate (ESR), platelet count (PLT), and globulin (r=0.624, 0.324, 0.402, 0.382, 0.467, and 0.386 respectively, all P<0.05), but negatively correlated with serum albumin (r=-0.306, P<0.05). The serum level of IL-9 was positively correlated with the levels of CRP, PCT, ESR, PLT, and globulin (r=0.365, 0.456, 0.403, 0.423, and 0.453 respectively, all P<0.05), but negatively correlated with serum albumin (r=-0.343, P<0.05).

CONCLUSIONS

The children in the acute stage of KD show significant increases in the percentage of peripheral Th9 cells and serum cytokine IL-9 level, which return to normal in the recovery stage. In the acute stage of KD, the expression levels of Th9 and IL-9 are closely correlated with laboratory markers. The results suggest that Th9 cells and IL-9 play important roles in the pathogenesis and outcome of KD.

The Effects of IL-22 on the Inflammatory Mediator Production, Proliferation, and Barrier Function of HUVECs

The aim of this study was to investigate the effects of interleukin (IL)-22 on proliferation function and inflammatory mediator production and barrier function of human umbilical vein endothelial cells (HUVECs). The expression of mRNA was detected by RT-PCR. The proliferation ability of cells was evaluated using a cell counting kit assay. Real-time quantitative PCR and Western blot were used to detect the expression of inflammatory mediators. The endothelial barrier permeability was assessed by measuring permeability to FITC-labeled dextran. The distribution of occludin was detected by immunofluorescence. IL-22R1 mRNA expression was noted in HUVECs. IL-22 could enhance the proliferation ability of HUVECs and suppress lipopolysaccharide (LPS)-induced proliferation inhibition in these cells. IL-22 also enhanced the production of CCL2 and CCL20 by HUVECs. Besides, IL-22 could improve barrier function and decrease LPS-induced increased cellular permeability and inhibit the LPS-induced destruction of occludin in HUVECs. IL-22 may play a protective role in the development of vasculitis.

Markedly elevated CD64 expression on neutrophils and monocytes as a biomarker for diagnosis and therapy assessment in Kawasaki disease

OBJECTIVE

Kawasaki disease (KD) is the most commonly encountered inflammatory disease in children. However, its pathogenesis and diagnostic biomarkers have not been fully investigated. We examined the activation of neutrophils and monocytes in KD.

METHODS

We studied the expression of the Fcγ-receptors CD64 and CD16 on neutrophils and monocytes in KD before and after the treatment with intravenous infusion of high dose immunoglobulin (IVIG). Bacterial infections were addressed as well.

RESULTS

CD64 expression on neutrophils and monocytes was dramatically increased at the onset of KD flare-ups, but later decreased just after IVIG. Similarly, CD16-positive monocytes were observed at the onset and were less apparent after therapy. The addition of immunoglobulin did not block the expression of CD64 or CD16 in vitro. Serum G-CSF in the majority of patients, and IFN-γ in some patients, were elevated during flares but decreased after treatment.

CONCLUSION

Our findings demonstrate that remarkable CD64 expression during KD flare-ups may serve as a biomarker for diagnosis. Evaluation of CD64 is also potentially useful for the determination of treatment efficacy in KD.

Differences in Anti-Inflammatory Actions of Intravenous Immunoglobulin between Mice and Men: More than Meets the Eye

Intravenous immunoglobulin (IVIg) is a therapeutic preparation of polyspecific human IgGs purified from plasma pooled from thousands of individuals. When administered at a high dose, IVIg inhibits inflammation and has proven efficacy in the treatment of various autoimmune and systemic inflammatory diseases. Importantly, IVIg therapy can ameliorate both auto-antibody-mediated and T-cell mediated immune pathologies. In the last few decades, extensive research in murine disease models has resulted in the elucidation of two novel anti-inflammatory mechanisms-of-action of IVIg: induction of FcγRIIB expression by sialylated Fc, and stimulation of regulatory T cells. Whereas controversial findings in mice studies have recently inspired intense scientific debate regarding the validity of the sialylated Fc-FcγRIIB model, the most fundamental question is whether these anti-inflammatory mechanisms of IVIg are operational in humans treated with IVIg. In this review, we examine the evidence for the involvement of these anti-inflammatory mechanisms in the therapeutic effects of IVIg in humans. We demonstrate that although several elements of both immune-modulatory pathways of IVIg are activated in humans, incorrect extrapolations from mice to men have been made on the molecular and cellular components involved in these cascades that warrant for critical re-evaluation of these anti-inflammatory mechanisms of IVIg in humans.