Male-specific association of the FCGR2A His167Arg polymorphism with Kawasaki disease

Kawasaki disease and the environment: an enigmatic interplay

Kawasaki disease (KD) is a common systemic vasculitis of childhood. Although it has been almost 6 decades since Dr. Tomisaku Kawasaki reported the first case series of KD, the underlying cause remains a mystery. KD is a self-limiting disease. However, a dreaded complication is development of coronary artery abnormalities (CAAs). KD is the most common cause of acquired heart disease in children in the developed world and is being increasingly reported from developing countries too. Over the years, significant observations have been made about epidemiology of KD. It usually affects children below 5, has male preponderance and has significantly higher incidence in North East Asian countries. While several hypotheses have been proffered for etiology of KD, none have been conclusive. These include associations of KD epidemics in Japan and the United Stated with changes in tropospheric wind patterns suggesting wind-borne agents, global studies showing peaks of incidence related to season, and increased rates in populations with a higher socioeconomic profile related to hygiene hypothesis and vaccination. Furthermore, the self-limiting, febrile nature of KD suggests an infectious etiology, more so with sudden decline noted in cases in Japan with onset of COVID-19 mitigation measures. Finally, single nucleotide polymorphisms have been identified as possible risk alleles in patients with KD and their significance in the pathogenesis of this disease are also being defined. The purpose of this review is to elucidate the puzzling associations of KD with different environmental factors. Looking at patterns associated with KD may help us better predict and understand this disease.

Whole-Exome Sequencing for Identification of Potential Sex-Biased Variants in Kawasaki Disease Patients

Kawasaki disease (KD) is an autoimmune disease of unknown etiology and has become a main cause of childhood acquired heart disease. KD is more prevalent in males than in females. The reason for this sex bias is unknown. Here, we used whole-exome sequencing (WES) to identify significantly different variants between male and female KD patients. From WES result, a total of 19,500 shared genetic variants in 8421 genes were captured via a series of filters. Further comparisons based on sex were performed to obtain 34 potential sex-biased variants in 34 genes for GO and Reactome Gene Sets enrichment analyses. Moreover, we selected 6 variants associated with immune, cells adhesion, platelet function, homeostasis, and ion channel signaling and expanded the sample size (1247 KD patients containing 713 males and 534 females, 803 healthy population containing 481 males and 322 females) for genotyping validation. From the results, USH2A/rs148135241, LMO7/rs142687160, CEMIP/rs12441101, and EFCC1/rs142391828 presented significant differences of alleles/genotypes frequency distributions between male and female only in KD patients (which were consistent with the result of WES analysis) but not in healthy population. In addition, the result also found that only EFCC1/rs142391828 polymorphism was associated with KD susceptibility. This result suggested that those four variants might play critical roles in sex bias in KD. The study would be in favor of a sex-specific genome atlas establishing and novel sex-specific precision therapies development for KD.

Whole-exome sequencing analysis identifies novel variants associated with Kawasaki disease susceptibility

BACKGROUND

Kawasaki disease (KD) is an acute pediatric vasculitis affecting genetically susceptible infants and children. Although the pathogenesis of KD remains unclear, growing evidence links genetic susceptibility to the disease.

METHODS

To explore the genes associated with susceptibility in KD, we applied whole-exome sequencing to KD and control subjects from Yunnan province, China. We conducted association study analysis on the two groups.

RESULTS

In this study, we successfully identified 11 significant rare variants in two genes (MYH14 and RBP3) through the genotype/allele frequency analysis. A heterozygous variant (c.2650G > A, p.V884M) of the RBP3 gene was identified in 12 KD cases, while eight heterozygous variants (c.566G > A, p.R189H; c.1109 C > T, p.S370L; c.3917T > G, p.L1306R; c.4301G > A, p.R1434Q; c.5026 C > T, p.R1676W; c.5329 C > T, p.R1777C; c.5393 C > A, p.A1798D and c.5476 C > T, p.R1826C) of the MYH14 gene were identified in 8 KD cases respectively.

CONCLUSION

This study suggested that nine variants in MYH14 and RBP3 gene may be associated with KD susceptibility in the population from Yunnan province.

Kawasaki disease in Malaysia: Biochemical profile, characterization, diagnosis and treatment

Introduction

Kawasaki disease (KD) is an acute idiopathic systemic vasculitis with a self- limiting course that predominantly affects children under 5 years old, particularly in the East Asian countries. Nevertheless, to date, the data on KD in Malaysia are limited. This study aimed to evaluate the epidemiology, clinical features, treatment, and outcomes of KD among the pediatric patients admitted to Hospital Canselor Tunku Muhriz (HCTM), Kuala Lumpur, Malaysia.

Method

A retrospective cohort study of 66,500 pediatric patients presented at HCTM from the year 2004 to 2021 was conducted.

Results

62 KD cases out of 66,500 pediatric admissions were reported, with a male-to-female ratio of 1.58 to 1. Majority of KD patients (95.0%) were younger than 5 years old. Prior infection was reported in 5 KD patients (8.1%). Apart from the classical features, manifestations of various organ systems including cardiovascular (16.1%), gastrointestinal (43.5%), neurological (1.61%), musculoskeletal (1.61%), and genitourinary (17.7%) systems were observed. There was a significant association between sterile pyuria and coronary artery aneurysm (CAA) (p < 0.05). Interestingly, abnormal liver parameters (p < 0.05) and incomplete KD (p < 0.05) were significantly related to IVIG resistance.

Discussion

The presence of family history, immunological disorder, and previous infection in our KD patients suggested that there is a possibility of genetic, immunological, and infectious roles in the pathophysiology of KD. IVIG resistance is more likely to occur in KD patients with hepatic dysfunction or incomplete KD presentation. These findings highlighted the significant contribution of laboratory parameters to the prognosis of KD, prompting more in-depth research on the KD scoring systems and their relevance in this country.

The role of semaphorins in cardiovascular diseases: Potential therapeutic targets and novel biomarkers

Semaphorins (Semas), which belongs to the axonal guidance molecules, include 8 classes and could affect axon growth in the nervous system. Recently, semaphorins were found to regulate other pathophysiological processes, such as immune response, oncogenesis, tumor angiogenesis, and bone homeostasis, through binding with their plexin and neuropilin receptors. In this review, we summarized the detailed role of semaphorins and their receptors in the pathological progression of various cardiovascular diseases (CVDs), highlighting that semaphorins may be potential therapeutic targets and novel biomarkers for CVDs.

FCGR2A-HH Gene Variants Encoding the Fc Gamma Receptor for the C-Reactive Protein Are Associated with Enhanced Monocyte CD32 Expression and Cardiovascular Events’ Recurrence after Primary Acute Coronary Syndrome

Fcγ receptors (FcγRs) interact with the C-reactive protein (CRP) and mediate activation of inflammation-related pathogenic mechanisms affecting cardiovascular health. Our study evaluated whether FcγRIIA and FcγRIIIA profiles are associated with the recurrence of adverse cardiovascular events during the first year after a primary acute coronary syndrome (ACS). The primary endpoint was the recurrence of cardiovascular events (RCE), identified as a composite outcome comprising acute heart failure (AHF) and major adverse cardiovascular events (MACE). We obtained blood samples of 145 ACS patients to measure hsCRP circulating levels, to identify FcγRIIA-131RH rs1801274 and FcγRIIIA-158FV rs396991 polymorphisms, to analyze circulating monocytes and NK cell subsets expressing CD16 and CD32, and to detect serum-mediated FCGR2A-HH activation by luciferase reporter assays. The hsCRP, CD32-expression, and Fc-R mediated activation levels were similar in all patients regardless of their MACE risk. In contrast, the hsCRP levels and the proportion of CD14+ circulating monocytes expressing the CD32 receptor for CRP were significantly higher in the patients who developed AHF. The FCGR2A rs1801274 HH genotype was significantly more common in patients who developed RCE and MACE than in RCE-free patients and associated with an enhanced percentage of circulating CD32+CD14+ monocytes. The FCGR2A-HH genotype was identified as an independent predictor of subsequent RCE (OR, 2.7; p = 0.048; CI, 1.01–7.44) by multivariate analysis. These findings bring preliminary evidence that host FCGR2A genetic variants can influence monocyte CD32 receptor expression and may contribute to the fine-tuning of CD32-driven chronic activating signals that affect the risk of developing RCEs following primary ACS events.

Spatiotemporal clusters of Kawasaki disease in South Korea from 2008 to 2017: A municipal-level ecological study

INTRODUCTION

As the etiology of Kawasaki disease (KD) remains unknown, identifying spatiotemporal clusters with proper stratification of KD could provide further evidence for investigating the triggers of KD. However, spatiotemporal distributions of KD with sex stratification have never been reported. Therefore, we aimed to analyze the spatiotemporal patterns of KD by sex in South Korea.

METHODS

We extracted epidemiologic week (Epiweek)-based KD cases in patients <5 years of age (ICD-10-CM code: M303) from 2008 to 2017 national health insurance service data at the 250 municipal level. To determine whether spatial autocorrelation and persistent municipal-level clusters exist, year- and sex-stratified global Moran's I statistics, Getis-Ord Gi* statistics, and emerging hotspot analysis on KD incidence were conducted.

RESULTS

A total of 72,510 KD cases were reported between 2008 and 2017 (male-to-female ratio = 1.40:1). Incidence has increased since 2008, with the highest incidence in 2016 (396.8 per 100,000 population). KD had seasonality of winter and summer but different by sex. Positive spatial autocorrelation was consistently reported in every stratum, with the 2011-2014 period having the strongest index value (total sex I = 0.286, p < 0.001; male I = 0.242, p < 0.001; female I = 0.213, p < 0.001). Hot spots were consistently detected in the northern parts, and cold spots were in the southern part for 9 years in both sexes. The emerging hot spot analysis showed new, consecutive, and sporadic hot spots on the northwestern and eastern coasts and new and sporadic cold spots in the southwestern part. However, the distribution and proportion of hot or cold spot types differed according to sex.

DISCUSSION

The spatiotemporal features of KD had limits to concluding that only infectious triggers result in KD occurrence. Therefore, our findings support the notion that KD is a syndrome with multiple factors, including infectious, genetic, and environmental factors, that are associated with sex differences.

Identification of novel locus associated with coronary artery aneurysms and validation of loci for susceptibility to Kawasaki disease

Kawasaki disease (KD) is a paediatric vasculitis associated with coronary artery aneurysms (CAA). Genetic variants influencing susceptibility to KD have been previously identified, but no risk alleles have been validated that influence CAA formation. We conducted a genome-wide association study (GWAS) for CAA in KD patients of European descent with 200 cases and 276 controls. A second GWAS for susceptibility pooled KD cases with healthy paediatric controls from vaccine trials in the UK (n = 1609). Logistic regression mixed models were used for both GWASs. The susceptibility GWAS was meta-analysed with 400 KD cases and 6101 controls from a previous European GWAS, these results were further meta-analysed with Japanese GWASs at two putative loci. The CAA GWAS identified an intergenic region of chromosome 20q13 with multiple SNVs showing genome-wide significance. The risk allele of the most associated SNV (rs6017006) was present in 13% of cases and 4% of controls; in East Asian 1000 Genomes data, the allele was absent or rare. Susceptibility GWAS with meta-analysis with previously published European data identified two previously associated loci (ITPKC and FCGR2A). Further meta-analysis with Japanese GWAS summary data from the CASP3 and FAM167A genomic regions validated these loci in Europeans showing consistent effects of the top SNVs in both populations. We identified a novel locus for CAA in KD patients of European descent. The results suggest that different genes determine susceptibility to KD and development of CAA and future work should focus on the function of the intergenic region on chromosome 20q13.

Hygiene Hypothesis as the Etiology of Kawasaki Disease: Dysregulation of Early B Cell Development

Kawasaki disease (KD) is an acute systemic vasculitis that occurs predominantly in children under 5 years of age. Despite much study, the etiology of KD remains unknown. However, epidemiological and immunological data support the hygiene hypothesis as a possible etiology. It is thought that more sterile or clean modern living environments due to increased use of sanitizing agents, antibiotics, and formula feeding result in a lack of immunological challenges, leading to defective or dysregulated B cell development, accompanied by low IgG and high IgE levels. A lack of B cell immunity may increase sensitivity to unknown environmental triggers that are nonpathogenic in healthy individuals. Genetic studies of KD show that all of the KD susceptibility genes identified by genome-wide association studies are involved in B cell development and function, particularly in early B cell development (from the pro-B to pre-B cell stage). The fact that intravenous immunoglobulin is an effective therapy for KD supports this hypothesis. In this review, I discuss clinical, epidemiological, immunological, and genetic studies showing that the etiopathogenesis of KD in infants and toddlers can be explained by the hygiene hypothesis, and particularly by defects or dysregulation during early B cell development.

Rapid review of multisystem inflammatory syndrome in paediatrics: What we know one year later

Background

: Multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19) is an emerging condition that was first identified in paediatrics at the onset of the COVID-19 pandemic. The condition is also known as pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 (PIMS-TS or PIMS), and multiple definitions have been established for this condition that share overlapping features with Kawasaki Disease and toxic shock syndrome.

Methods

: A review was conducted to identify literature describing the epidemiology of MIS-C, published up until March 9, 2021. A database established at the Public Health Agency of Canada with COVID-19 literature was searched for articles referencing MIS-C, PIMS or Kawasaki Disease in relation to COVID-19.

Results

: A total of 195 out of 988 articles were included in the review. The median age of MIS-C patients was between seven and 10 years of age, although children of all ages (and adults) can be affected. Multisystem inflammatory syndrome in children disproportionately affected males (58% patients), and Black and Hispanic children seem to be at an elevated risk for developing MIS-C. Roughly 62% of MIS-C patients required admission to an intensive care unit, with one in five patients requiring mechanical ventilation. Between 0% and 2% of MIS-C patients died, depending on the population and available interventions.

Conclusion

: Multisystem inflammatory syndrome in children can affect children of all ages. A significant proportion of patients required intensive care unit and mechanical ventilation and 0%-2% of cases resulted in fatalities. More evidence is needed on the role of race, ethnicity and comorbidities in the development of MIS-C.

Single-Nucleotide Polymorphism LncRNA AC008392.1/rs7248320 in CARD8 is Associated with Kawasaki Disease Susceptibility in the Han Chinese Population

Background

Kawasaki disease (KD) is a multisystem vasculitis in infants and young children and involved in the NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome activation. Genetic factors may increase the risk of KD. To assess the association between rs7248320 in long noncoding RNA (lncRNA) AC008392.1 located in the upstream region of CARD8 and the risk of KD, a case–control study was conducted in the Han Chinese population.

Methods

This study genotyped the polymorphism rs7248320 in the lncRNA AC008392.1 gene using the TaqMan real-time polymerase chain reaction assay. The genetic contribution of rs7248320 was evaluated using odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression analysis. The association between rs7248320 and KD susceptibility was analyzed by performing a hospital-based case–control study including 559 KD patients and 1055 non-KD controls.

Results

In this study, a significant relationship between rs7248320 and KD risk was observed in the genotype/allele frequency distribution. The rs7248320 polymorphism was associated with a significantly decreased risk of KD after adjustment for age and sex (AG vs AA: adjusted OR = 0.80, 95% CI: 0.64–0.99, P = 0.0421; GG vs AA: adjusted OR = 0.71, 95% CI: 0.51–1.00, P = 0.0492; AG/GG vs AA: adjusted OR = 0.78, 95% CI: 0.63–0.96, P = 0.0186). Moreover, the rs7248320 G allele also exhibited a decreased risk for KD (adjusted OR = 0.83, 95% CI: 0.72–0.97, P = 0.0193) compared with the A allele. In the stratification analysis, compared to the rs7248320 AA genotype, AG/GG genotypes were more protective for males (OR = 0.71, 95% CI: 0.55–0.93, P = 0.0122).

Conclusion

This study suggests for the first time that the lncRNA AC008392.1 rs7248320 polymorphism may be involved in KD susceptibility in the Han Chinese population.

Epidemiology, clinical characteristics, and immediate outcome of Kawasaki disease: a population-based study from a tropical country

Data on Kawasaki disease from tropical countries are scarce. Hence, this population-based study aims to determine the epidemiology, clinical characteristics, and outcome of Kawasaki disease in children enrolled in the Kawasaki disease registry between 2006 and 2019 in Southern Malaysia. Diagnosis of Kawasaki disease was made using standard criteria. Primary outcome measure was a coronary artery aneurysm. Multivariable logistic regression was used to analyze the associated risk factors for coronary artery aneurysm. There were 661 Kawasaki disease, with 27% incomplete and 11% atypical presentations. Male-to-female ratio was 2:1, and median age of diagnosis was 1.4 years (interquartile range 9 to 32 months). Incidence in children of less than 5 years was 14.8 (95% confidence interval [CI]: 13.6 to 16.0) per 100,000 population, higher in males (19/100,000) and Chinese (22/100,000), with a gradual increase from 5.7/100,000 in 2006 to 19.6/100,000 in 2019, p < 0.001. Incidence in children between 5 and 9 years old was 1.3 (95% CI: 0.9 to 1.6) per 100,000 population and remained stable over time. There was a seasonal pattern with peak incidence during the rainy season. Out of 625 intravenous immunoglobulins (IVIG)-treated Kawasaki disease, 7.4% were resistant, and 9% had coronary artery aneurysms. Atypical presentation, male sex, late diagnosis, and IVIG resistance were independent risk factors for coronary artery aneurysms.Conclusions: Despite the tropical climate, Kawasaki disease epidemiology is similar to non-tropic regions with seasonal patterns and a rising incidence. Atypical presentation, male sex, late diagnosis, and IVIG resistance were significantly associated with coronary artery aneurysms. What is Known: • Kawasaki disease predominantly occurs in males, children less than 5 years old, and the Asian population. • Male sex, late diagnosis, incomplete Kawasaki disease, and IVIG resistance were associated with coronary artery aneurysms. What is New: • In multi-ethnic Asian countries such as Malaysia, ethnic Chinese have a higher prevalence of Kawasaki disease compared to other ethnicities. • Kawasaki disease with atypical presentation can occur in both complete and incomplete Kawasaki disease and is significantly associated with a coronary artery aneurysm.

Cumulative Evidence for Association between IL-10 Polymorphisms and Kawasaki Disease Susceptibility: A Systematic Review and Meta-Analysis

BACKGROUND

This meta-analysis was carried out to evaluate the associations between IL-10 polymorphisms and Kawasaki disease (KD) risk.

METHODS

A comprehensive literature search was performed using PubMed, EMBASE, China National Knowledge Infrastructure and SciELO for all relevant studies evaluating IL-10 polymorphism and susceptibility to KD. The associations were measured by odds ratios (ORs) and its corresponding 95% confidence intervals (CIs).

RESULTS

A total of 13 studies including four studies on -1082 A > G, four studies on -819 T > C and five studies on -592 A > C polymorphism were selected. Pooled data revealed that IL-10 -592 A > C polymorphism was significantly associated with an increased risk of KD (C vs. A: OR = 0.402, 95% CI 0.194-0.832, p = 0.014). However, IL-10 -1082 A > G and -819 T > C polymorphisms were not significantly associated with risk of KD under all five genetic models.

CONCLUSIONS

Our results revealed that IL-10 -592 A > C polymorphism was associated with risk of KD, while IL-10 -1082 A > G and -819 T > C polymorphisms were not involved in the development of KD.

Identification of increased expression of activating Fc receptors and novel findings regarding distinct IgE and IgM receptors in Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is associated with expression and methylation of Fc gamma receptor genes. We characterized immunoglobulin A (IgA), IgE, IgG, and IgM receptor expression levels in KD.

METHODS

Fc receptor expression levels were characterized using GeneChip Human Transcriptome Array 2.0 (HTA 2.0) with 18 KD patients, 18 non-febrile controls, and 18 febrile controls. Another 48 control individuals and 46 patients with KD were measured using pyrosequencing for the methylation levels.

RESULTS

The mRNA expression levels of FCER1A and FCER2 were significantly lower in KD patients than in non-febrile controls and then rose following treatments with intravenous immunoglobulin (IVIG). Expression levels of FCER1G increased compared to the non-febrile subjects and then subsided after IVIG. FCER1A methylation was significantly lower among KD patients and even lower in KD patients with IVIG resistance. HTA analysis revealed higher mRNA levels of FCAR, FCGR1C, and FCGR2A in KD patients. FCMR mRNA expression levels were significantly lower in KD patients. FCMR expression levels rose after IVIG treatment. After IVIG, FCGR1A, B, and C decreased even lower than the febrile controls.

CONCLUSION

This is the first study indicating that IgA, IgE, IgG, and IgM receptors are associated with KD. We highlighted potential biomarkers related to Fc receptors and their regulation.

Association Between rs12037447, rs146732504, rs151078858, rs55723436, and rs6094136 Polymorphisms and Kawasaki Disease in the Population of Polish Children

Background: Kawasaki disease (KD) is an acute self-limited febrile vasculitis that mainly affects young children. Coronary artery involvement is the most serious complication in children with KD. It is currently the leading cause of acquired cardiac disease in children from developed countries. Literature data indicate a significant role of genetic susceptibility to KD. Objective: The aim of this study was to perform the first Genome-Wide Association Study (GWAS) in a population of Polish children with KD and identify susceptible genes involved in the pathogenesis of KD. Materials and Methods: The blood samples of Kawasaki disease patients (n = 119) were collected between 2016 and 2020, isolated and stored at the Department of Pediatrics, Nutrition and Metabolic Diseases, Children's Memorial Health Institute in Warsaw. The control group was based on Polish donors (n = 6,071) registered as the POPULOUS collection at the Biobank Lab of The Department of Molecular Biophysics in University of Lodz. DNA samples were genotyped for 558,231 Single Nucleotide Polymorphisms (SNPs) using the 24 × 1 Infinium HTS Human Core Exome microarrays according to the protocol provided by the manufacturer. In order to discover and verify genetic risk-factors for KD, association analysis was carried out using PLINK 1.9. Results: Of all 164,395 variants, 5 were shown to occur statistically (p_adjusted < 0.05) more frequent in Kawasaki disease patients than in controls. Those are: rs12037447 in non-coding sequence (p_adjusted = 8.329 × 10^-4, OR = 8.697, 95% CI; 3.629-20.84) and rs146732504 in KIF25 (p_adjusted = 0.007354, OR = 11.42, 95% CI; 3.79-34.43), rs151078858 in PTPRJ (p_adjusted = 0.04513, OR = 8.116, 95% CI; 3.134-21.01), rs55723436 in SPECC1L (p_adjusted = 0.04596, OR = 5.596, 95% CI; 2.669-11.74), rs6094136 in RPN2 (p_adjusted = 0.04755, OR = 10.08, 95% CI; 3.385-30.01) genes. Conclusion: Polymorphisms of genes KIF25, PTRPJ, SPECC1L, RNP2 may be linked with the incidence of Kawasaki disease in Polish children.

Low FCMR mRNA expression in leukocytes of patients with Kawasaki disease six months after disease onset

BACKGROUND

Immunoglobulin (Ig) M plays an important role in immune regulation. FCMR-encoded FcμR is a receptor of IgM. Previous research has suggested that IgM levels may be involved in the coronary artery lesions of Kawasaki syndrome or Kawasaki disease (KD). In this study, we aimed to explore the roles of mRNA expressions of IgM receptors, particularly FCMR, in KD patients. FCMR encodes the Fc fragment of immunoglobulin M receptor.

METHODS

We enrolled 60 KD patients and 55 non-KD controls. Whole-blood leukocytes were isolated, and the mRNA expression for FCMR was determined. Each mRNA consisted of a sample taken before intravenous immunoglobulin (IVIG) was administered (acute, KD1) and those taken at three weeks, six months, and one year later (KD3, KD4, KD5). Paired KD subjects were analyzed from both the acute and convalescent phases (n = 28).

RESULTS

After six months and one year of treatment, KD patients still apparently have lower FCMR compared with controls (P = .004). FCMR expressions were downregulated in male patients with KD prior to IVIG administration (P = .044). The FCMR of paired KD patients who received IVIG treatments after six months was significantly lower than before undergoing IVIG treatment (P = .044). Expressions in the polymorphonuclear leukocytes were similar to those in the peripheral blood mononuclear cells.

CONCLUSION

The unique data supported that FCMR is expressed by granulocytes at RNA levels in humans and demonstrated lower FCMR six months after the onset of KD. The findings remind us of the need to track the health of children with KD over the long term, even if we think patients have fully recovered.

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.

Adjuvant herbal therapy for targeting susceptibility genes to Kawasaki disease: An overview of epidemiology, pathogenesis, diagnosis and pharmacological treatment of Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is a self-limiting acute systemic vasculitis occur mainly in infants and young children under 5 years old. Although the use of acetylsalicylic acid (AAS) in combination with intravenous immunoglobulin (IVIG) remains the standard therapy to KD, the etiology, genetic susceptibility genes and pathogenic factors of KD are still un-elucidated.

PURPOSE

Current obstacles in the treatment of KD include the lack of standard clinical and genetic markers for early diagnosis, possible severe side effect of AAS (Reye's syndrome), and the refractory KD cases with resistance to IVIG therapy, therefore, this review has focused on introducing the current advances in the identification of genetic susceptibility genes, environmental factors, diagnostic markers and adjuvant pharmacological intervention for KD.

RESULTS

With an overall update in the development of KD from different aspects, our current bioinformatics data has suggested CASP3, CD40 and TLR4 as the possible pathogenic factors or diagnostic markers of KD. Besides, a list of herbal medicines which may work as the adjunct therapy for KD via targeting different proposed molecular targets of KD have also been summarized.

CONCLUSION

With the aid of modern pharmacological research and technology, it is anticipated that novel therapeutic remedies, especially active herbal chemicals targeting precise clinical markers of KD could be developed for accurate diagnosis and treatment of the disease.

Interleukin-1 Beta-Mediated Sex Differences in Kawasaki Disease Vasculitis Development and Response to Treatment

OBJECTIVE

Kawasaki disease (KD) is the leading cause of acute vasculitis and acquired heart disease in children in developed countries. Notably, KD is more prevalent in males than females. We previously established a key role for IL (interleukin)-1 signaling in KD pathogenesis, but whether this pathway underlies the sex-based difference in susceptibility is unknown. Approach and Results: The role of IL-1 signaling was investigated in the Lactobacillus casei cell wall extract-induced experimental mouse model of KD vasculitis. Five-week-old male and female mice were injected intraperitoneally with PBS, Lactobacillus caseicell wall extract, or a combination of Lactobacillus caseicell wall extract and the IL-1 receptor antagonist Anakinra. Aortitis, coronary arteritis inflammation score and abdominal aorta dilatation, and aneurysm development were assessed. mRNA-seq (messenger RNA sequencing) analysis was performed on abdominal aorta tissue. Publicly available human transcriptomics data from patients with KD was analyzed to identify sex differences and disease-associated genes. Male mice displayed enhanced aortitis and coronary arteritis as well as increased incidence and severity of abdominal aorta dilatation and aneurysm, recapitulating the increased incidence in males that is observed in human KD. Gene expression data from patients with KD and abdominal aorta tissue of Lactobacillus caseicell wall extract-injected mice showed enhanced Il1b expression and IL-1 signaling genes in males. Although the more severe IL-1β-mediated disease phenotype observed in male mice was ameliorated by Anakinra treatment, the milder disease phenotype in female mice failed to respond.

CONCLUSIONS

IL-1β may play a central role in mediating sex-based differences in KD, with important implications for the use of anti-IL-1β therapies to treat male and female patients with KD.

Seasonal Variation in Epidemiology of Kawasaki Disease-Related Coronary Artery Abnormalities in Japan, 1999-2017

BACKGROUND

Epidemiological studies show a U-shaped tendency in Kawasaki disease (KD)-related coronary artery abnormalities (CAAs) across age categories. Since studies suggest seasonal variations in KD onset, this study aimed to clarify the epidemiologic features of CAAs, considering the seasons of KD-occurrence.

METHODS

We analyzed 2,106 (males = 1,215, females = 891) consecutive KD cases from October 1999 through September 2017 using our electronic database of annual surveys, targeting all hospitals with pediatric departments across Wakayama, Japan. The primary outcome was the presence/absence of CAAs measured by echocardiography 1 month after KD onset. Odds ratios (ORs) and 95% confidence intervals (CIs) of combined patient age and sex for CAAs were calculated using logistic regression models adjusted for four seasons.

RESULTS

The median age was 25 (range, 1-212) months. The proportion of males decreased with increasing age. The youngest age group (<6 months) showed an inverse summer/autumn to winter/spring ratio (>1.0) in KD-occurrence. CAAs were observed in 2.8% of cases (males = 3.4%, females = 2.1%), which significantly lessened in summer than in other seasons. Moreover, 50% (n = 4/8) of cases with giant aneurysms experienced KD in autumn. Adjusted ORs for CAAs among males aged ≥60 months (3.0; 95%, CI 1.2-7.5) and females aged <6 months (3.6; 95%, CI 1.1-11.8) were significantly higher than those among males aged 12-35 months.

CONCLUSIONS

Cumulative 18-year data of consecutive KD cases from one area suggest the influence of interactions between patient age and sex on the development of KD-related CAAs. The season of KD-occurrence may reflect the diversity of agents.

CD32a polymorphism rs1801274 affects the risk of Kawasaki disease

Aim: To analyze the impact of CD32a polymorphism rs1801274 on the occurrence of Kawasaki disease (KD) through the meta-analysis.Methods: The correlation between CD32a polymorphism rs1801274 and the susceptibility to KD was appraised using summarized odds ratios (ORs) with their 95% confidence intervals (95% CIs). Besides, stratification analyses were further implemented on the basis of ethnicity and control source, respectively. Between-study heterogeneity was checked adopting chi-square-based Q test, with p < .05 as significant level. And results from Q test determined which model would be employed for OR calculation, fixed- or random-effects. Sensitivity analysis was accomplished to test the stability of final results. Potential publication bias among included studies was investigated using Begg's funnel plot and Egger's test. If publication bias was significant, its influence on overall estimates would be measured adopting the trim-and-fill method.Results: CD32a polymorphism rs1801274 significantly increased KD risk in total analysis under the comparisons of AA vs. GG, AA + AG vs. GG, AA vs. GG + AG, A vs. G and AG vs. GG (OR = 2.69, 95% CI = 1.39-5.20; OR = 2.00, 95% CI = 1.23-3.26; OR = 1.90, 95% CI = 1.23-2.94; OR = 1.77, 95% CI = 1.34-2.34; OR = 1.53, 95% CI = 1.07-2.19). After stratification analysis by ethnicity, similar tendency was also observed in Caucasian and Asian subgroups under corresponding genetic models. And parallel results were replicated in population-based and other-source subgroups after stratified analysis by control source, under some contrasts.Conclusion: CD32a polymorphism rs1801274 has strong relation to KD onset, and the presence of its A allele could elevate the disease incidence.

Current State of Precision Medicine in Primary Systemic Vasculitides

Precision medicine (PM) is an emerging data-driven health care approach that integrates phenotypic, genomic, epigenetic, and environmental factors unique to an individual. The goal of PM is to facilitate diagnosis, predict effective therapy, and avoid adverse reactions specific for each patient. The forefront of PM is in oncology; nonetheless, it is developing in other fields of medicine, including rheumatology. Recent studies on elucidating the genetic architecture of polygenic and monogenic rheumatological diseases have made PM possible by enabling physicians to customize medical treatment through the incorporation of clinical features and genetic data. For complex inflammatory disorders, the prevailing paradigm is that disease susceptibility is due to additive effects of common reduced-penetrance gene variants and environmental factors. Efforts have been made to calculate cumulative genetic risk score (GRS) and to relate specific susceptibility alleles for use of target therapies. The discovery of rare patients with single-gene high-penetrance mutations informed our understanding of pathways driving systemic inflammation. Here, we review the advances in practicing PM in patients with primary systemic vasculitides (PSVs). We summarize recent genetic studies and discuss current knowledge on the contribution of epigenetic factors and extracellular vesicles (EVs) in disease progression and treatment response. Implementation of PM in PSVs is a developing field that will require analysis of a large cohort of patients to validate data from genomics, transcriptomics, metabolomics, proteomics, and epigenomics studies for accurate disease profiling. This multi-omics approach to study disease pathogeneses should ultimately provide a powerful tool for stratification of patients to receive tailored optimal therapies and for monitoring their disease activity.

Potential regulatory SNPs in the ATXN7L3B and KRT15 genes are associated with gender-specific colorectal cancer risk

Aim: According to the current data, a major factor for phenotypic variation of complex traits and disease susceptibility is the cis-acting effects of noncoding variants on gene expression. Our purpose was to evaluate the association between colorectal cancer (CRC) and six single nucleotide polymorphisms identified using our original bioinformatics approach as regulatory and putatively related to CRC. Materials: One hundred and sixty CRC patients and 185 healthy controls have been genotyped for rs590352, rs2072580, rs78317230, rs3829202, rs11542583 and rs4796672. Results: Genotypes and alleles distributions of rs590352 of ATXN7L3B gene were significantly different between the male CRC subjects and controls. Significant correlation of genotype with CRC is observable for women only for the rs4796672 of KRT15 gene. Analysis of haplotypes reveals that rs2072580 of the ISCU and SART3 genes can be also associated with CRC. Conclusion: We have identified three SNPs associated with CRC risk and demonstrated a gender specificity of rs590352 and rs4796672.

Association between the miRNA-149 rs2292832 T>C polymorphism and Kawasaki disease susceptibility in a southern Chinese population

Background

Kawasaki disease (KD), which is characterized by vasculitis, is prone to occur in patients under 5 years of age, has an ambiguous etiology, and displays coronary artery lesions as the chief complication. Previous studies have linked miRNA‐149 to cancers, and rs2292832 T>C is related to allergic diseases and inflammatory bowel disease, which both show immune system disorders and coronary artery disease. Therefore, we performed a study concentrating on the association between the miRNA‐149 rs2292832 T>C polymorphism and KD susceptibility.

Methods

The subjects enrolled were 532 children with KD and 623 controls. We used TaqMan real‐time PCR to obtain the genotypes of the rs2292832 T>C polymorphism.

Results

Ultimately, no significant association was found between the miRNA‐149 rs2292832 T>C polymorphism and KD susceptibility, even in stratification analysis.

Conclusion

Our results indicated that in southern Chinese patients, the miRNA‐149 rs2292832 T>C polymorphism did not affect KD susceptibility, which needs to be further confirmed.

Lymphatic Function and Dysfunction in the Context of Sex Differences

Endothelial cells are the building blocks of the blood vascular system and exhibit well-characterized sexually dimorphic phenotypes with regard to chromosomal and hormonal sex, imparting innate genetic and physiological differences between male and female vascular systems and cardiovascular disease. However, even though females are predominantly affected by disorders of lymphatic vascular function, we lack a comprehensive understanding of the effects of sex and sex hormones on lymphatic growth, function, and dysfunction. Here, we attempt to comprehensively evaluate the current understanding of sex as a biological variable influencing lymphatic biology. We first focus on elucidating innate and fundamental differences between the sexes in lymphatic function and development. Next, we delve into lymphatic disease and explore the potential underpinnings toward bias prevalence in the female population. Lastly, we incorporate more broadly the role of the lymphatic system in sex-biased diseases such as cancer, cardiovascular disease, reproductive disorders, and autoimmune diseases to explore whether and how sex differences may influence lymphatic function in the context of these pathologies.

Gene-by-Sex Interactions in Mitochondrial Functions and Cardio-Metabolic Traits

We studied sex differences in over 50 cardio-metabolic traits in a panel of 100 diverse inbred strains of mice. The results clearly showed that the effects of sex on both clinical phenotypes and gene expression depend on the genetic background. In support of this, genetic loci associated with the traits frequently showed sex specificity. For example, Lyplal1, a gene implicated in human obesity, was shown to underlie a sex-specific locus for diet-induced obesity. Global gene expression analyses of tissues across the panel implicated adipose tissue "beiging" and mitochondrial functions in the sex differences. Isolated mitochondria showed gene-by-sex interactions in oxidative functions, such that some strains (C57BL/6J) showed similar function between sexes, whereas others (DBA/2J and A/J) showed increased function in females. Reduced adipose mitochondrial function in males as compared to females was associated with increased susceptibility to obesity and insulin resistance. Gonadectomy studies indicated that gonadal hormones acting in a tissue-specific manner were responsible in part for the sex differences.

Vasculitis Pathogenesis: Can We Talk About Precision Medicine?

Precision medicine is designing the medical care by taking into account the individual variability for each person. We have tried to address whether the existing data may guide precision medicine in primary systemic vasculitides (PSV). We have reviewed genome-wide association studies (GWAS) data, lessons from monogenic mimics of these diseases, and biomarker studies in immunoglobulin A vasculitis/Henoch–Schönlein purpura, Kawasaki disease, anti-neutrophil cytoplasmic antibody-associated vasculitis, polyarteritis nodosa (PAN), Takayasu arteritis, and Behçet’s disease (BD). GWAS provide insights about the pathogenesis of PSV while whole exome sequencing studies lead to discovery of monogenic vasculitides, phenotype of which could mimic other types of vasculitis such as PAN and BD. Monogenic vasculitides form a subgroup of vasculitis which are caused by single gene alterations and discovery of these diseases has enabled more specific therapies in these patients. With increasing number of studies on biomarkers, new targets for treatment appear and better and structured follow-up of PSV patients will become possible. Proteomics and metabolomics studies are required to better categorize our patients with PSV so that we can manage them appropriately and offer more targeted therapy.