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

Immunoglobulin G glycosylation and its alterations in aging-related diseases

Immunoglobulin G (IgG) is an important serum glycoprotein and a major component of antibodies. Glycans on IgG affect the binding of IgG to the Fc receptor or complement C1q, which in turn affects the biological activity and biological function of IgG. Altered glycosylation patterns on IgG emerge as important biomarkers in the aging process and age-related diseases. Key aging-related alterations observed in IgG glycosylation include reductions in galactosylation and sialylation, alongside increases in agalactosylation, and bisecting GlcNAc. Understanding the role of IgG glycosylation in aging-related diseases offers insights into disease mechanisms and provides opportunities for the development of diagnostic and therapeutic strategies. This review summarizes five aspects of IgG: an overview of IgG, IgG glycosylation, IgG glycosylation with inflammation mediation, IgG glycan changes with normal aging, as well as the relevance of IgG glycan changes to aging-related diseases. This review provides a reference for further investigation of the regulatory mechanisms of IgG glycosylation in aging-related diseases, as well as for evaluating the potential of IgG glycosylation changes as markers of aging and aging-related diseases.

Association of Genetic Polymorphisms in Kawasaki Disease with the Response to Intravenous Immunoglobulin Therapy

Kawasaki disease (KD) is an acute febrile and systemic vasculitis disease mainly affecting children < 5 years old. Although the first case of KD was reported in 1967 and despite extensive research on KD since then, the cause of the disease remains largely unknown. The most common complications of KD are coronary artery lesions (CAL), which significantly increase the risk of coronary heart disease. The standard treatment for KD is high-dose intravenous immunoglobulin (IVIG) plus aspirin within 10 days from symptoms' appearance, which has been shown to decrease the incidence of CAL to 5-7%. Despite the benefits of IVIG, about 25% of the patients treated with IVIG develop resistance or are unresponsive to the therapy, which represents an important risk factor for CAL development. The cause of IVIG unresponsiveness has not been fully elucidated. However, the role of gene polymorphisms in IVIG response has been suggested. Herein, we comprehensively review genetic polymorphisms in KD that have been associated with IVIG resistance/unresponsiveness and further discuss available models to predict IVIG unresponsiveness.Kindly check and confirm inserted city in affiliation [1] is correctly identified.confirm.

Systems biology and artificial intelligence analysis highlights the pleiotropic effect of IVIg therapy in autoimmune diseases with a predominant role on B cells and complement system

Intravenous immunoglobulin (IVIg) is used as treatment for several autoimmune and inflammatory conditions, but its specific mechanisms are not fully understood. Herein, we aimed to evaluate, using systems biology and artificial intelligence techniques, the differences in the pathophysiological pathways of autoimmune and inflammatory conditions that show diverse responses to IVIg treatment. We also intended to determine the targets of IVIg involved in the best treatment response of the evaluated diseases. Our selection and classification of diseases was based on a previously published systematic review, and we performed the disease characterization through manual curation of the literature. Furthermore, we undertook the mechanistic evaluation with artificial neural networks and pathway enrichment analyses. A set of 26 diseases was selected, classified, and compared. Our results indicated that diseases clearly benefiting from IVIg treatment were mainly characterized by deregulated processes in B cells and the complement system. Indeed, our results show that proteins related to B-cell and complement system pathways, which are targeted by IVIg, are involved in the clinical response. In addition, targets related to other immune processes may also play an important role in the IVIg response, supporting its wide range of actions through several mechanisms. Although B-cell responses and complement system have a key role in diseases benefiting from IVIg, protein targets involved in such processes are not necessarily the same in those diseases. Therefore, IVIg appeared to have a pleiotropic effect that may involve the collaborative participation of several proteins. This broad spectrum of targets and 'non-specificity' of IVIg could be key to its efficacy in very different diseases.

IgG N-glycans

Glycosylation, one of the most common post-translational modifications in mammalian cells, impacts many biological processes such as cell adhesion, proliferation and differentiation. As the most abundant glycoprotein in human serum, immunoglobulin G (IgG) plays a vital role in immune response and protection. There is a growing body of evidence suggests that IgG structure and function are modulated by attached glycans, especially N-glycans, and aberrant glycosylation is associated with disease states. In this chapter, we review IgG glycan repertoire and function, strategies for profiling IgG N-glycome and recent studies. Mass spectrometry (MS) based techniques are the most powerful tools for profiling IgG glycome. IgG glycans can be divided into high-mannose, biantennary complex and hybrid types, modified with mannosylation, core-fucosylation, galactosylation, bisecting GlcNAcylation, or sialylation. Glycosylation of IgG affects antibody half-life and their affinity and avidity for antigens, regulates crystallizable fragment (Fc) structure and Fcγ receptor signaling, as well as antibody effector function. Because of their critical roles, IgG N-glycans appear to be promising biomarkers for various disease states. Specific IgG glycosylation can convert a pro-inflammatory response to an anti-inflammatory activity. Accordingly, IgG glycoengineering provides a powerful approach to potentially develop effective drugs and treat disease. Based on the understanding of the functional role of IgG glycans, the development of vaccines with enhanced capacity and long-term protection are possible in the near future.

In silico screening and identification of deleterious missense SNPs along with their effects on CD-209 gene: An insight to CD-209 related-diseases

DC-SIGN receptor articulated by macrophages and dendritic cells is encoded by CD209 gene and plays a role to activate and proliferate the T-lymphocytes in response of virus attack. The dysfunctional activity of DC-SIGN receptor because of missense SNPs can lead to cause dengue haemorrhage fever, HIV-1 infection etc. Out of 11 transcripts of CD209, all missense SNPs of canonical transcript were retrieved from Ensembl database and evaluated by their deleteriousness by using Polyphen-2, PMut, SIFT, MutPred, PROVEAN and PhD-SNP together with stimulation of its complete 3D structure. 10 nsSNPs were chosen depending on both the significance value of nsSNP and their prediction among SNPs evaluating servers which are based on different algorithms. Moreover, the position and native role of 10 nsSNPs in wild 3D model has been described which assist to acknowledge their importance. This study urges the researcher’s community to experimentally validate these SNPs and their association in causing the diseases like dengue fever, Tuberculosis etc.

CD209 and Not CD28 or STAT6 Polymorphism Mediates Clinical Malaria and Parasitemia among Children from Nigeria

Malaria remains a significant disease, causing epic health problems and challenges all over the world, especially in sub-Saharan Africa. CD209 and CD28 genes act as co-stimulators and regulators of the immune system, while the STAT6 gene has been reported to mediate cytokine-induced responses. Single nucleotide polymorphisms of these genes might lead to differential disease susceptibility among populations at risk for malaria, due to alterations in the immune response. We aim to identify key drivers of the immune response to malaria infection among the three SNPs: CD209 (rs4804803), CD28 (rs35593994) and STAT6 (rs3024974). After approval and informed consent, we genotyped blood samples from a total of 531 children recruited from Nigeria using the Taqman SNP genotyping assay and performed comparative analysis of clinical covariates among malaria-infected children. Our results reveal the CD209 (rs4804803) polymorphism as a susceptibility factor for malaria infection, significantly increasing the risk of disease among children, but not CD28 (rs35593994) or STAT6 (rs3024974) polymorphisms. Specifically, individuals with the homozygous mutant allele (rs4804803G/G) for the CD209 gene have a significantly greater susceptibility to malaria, and presented with higher mean parasitemia. This observation may be due to a defective antigen presentation and priming, leading to an ineffective downstream adaptive immune response needed to combat infection, as well as the resultant higher parasitemia and disease manifestation. We conclude that the CD209 gene is a critical driver of the immune response during malaria infection, and can serve as a predictor of disease susceptibility or a biomarker for disease diagnosis.

CD209-336A/G promotor polymorphism and its clinical associations in sickle cell disease Egyptian Pediatric patients

OBJECTIVES

To detect the frequency of CD209 A>G polymorphism in sickle cell disease (SCD) Egyptian patients and to evaluate the use of CD209 A>G polymorphism as a genetic predictor of SCD clinical heterogeneity.

METHODS

A total of 100 Egyptian children with SCD and 100 Egyptian controls were tested for CD209 A>G polymorphism and were followed up prospectively between June 2012 and December 2014.

RESULTS

Comparison of CD209 A>G polymorphism among cases and controls did not show statistically significant difference (p = .742). In addition, comparison of the allelic frequency did not show statistically significant difference (p = .738). Infections occurred more frequently among the heterozygous genotype (AG; 60.5%) and homozygous genotype (GG; 75%) patients than among the wild (AA) genotype (24.1%; p < .001). The use of hydroxyurea treatment was significantly higher among the wild (AA) genotype (47%) than the heterozygous (AG; 21%) and homozygous (GG; 5%) genotypes (p = .003).

CONCLUSION

We found no significant difference between our population of Egyptian SCD cases and controls regarding CD209 A>G polymorphism. Infections occurred more frequently among the heterozygous genotype (AG) and homozygous genotype (GG) patients.

Association of Dectin-1 and DC-SIGN gene single nucleotide polymorphisms with fungal keratitis in the northern Han Chinese population

PURPOSE

Dendritic cell-associated C-type lectin-1 (Dectin-1) and dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) play a crucial role in the early procedure of fungal pathogen defenses. The present study evaluated the associations between Dectin-1 and DC-SIGN gene single nucleotide polymorphisms (SNPs) and susceptibility to fungal keratitis (FK) in the northern Han Chinese population.

METHODS

The polymorphisms of Dectin-1 (rs17206002, rs3901533, rs11053613, and rs3901532) and DC-SIGN (rs4804803, rs2287886, rs735239, and rs735240) for 109 FK patients and 220 matched healthy controls were determined by PCR and DNA direct sequencing assay.

RESULTS

Each SNP was consistent with Hardy-Weinberg equilibrium (p>0.05). The frequencies of genotypes and alleles for rs735239 and rs735240 (DC-SIGN) showed statistical differences between patients and control groups (p<0.05). The wild G allele of rs735239 and the wild A allele of rs735240 were significantly higher in patients (p=0.003, OR=1.766, 95% confidence interval [CI] 1.207-2.585; p=0.014, OR=1.609, 95% CI 1.100-2.355, respectively). No association with a risk of FK was found for the remaining SNPs (p>0.05) even after ruling out clinical characteristics, such as severity degree and case history. Carriers of the haplotype TC (rs4804803 and rs2287886) had a higher risk of developing fungal keratitis (p=0.007, OR=1.710, 95% CI 1.154-2.534). The distribution of haplotypes AG and GA (rs735239 and rs735240) between the two groups also showed significant differences (p=0.014, p=0.003, respectively).

CONCLUSIONS

Two SNPs of DC-SIGN (rs735239 and rs735240) are associated with susceptibility to FK in the northern Han Chinese population. The haplotypes of DC-SIGN may be susceptible to the risk of FK, whereas the analysis of Dectin-1 gene polymorphisms showed no significant association with FK risk. Further research with a larger sample is recommended.

Adult Kawasaki disease in a European patient: a case report and review of the literature

Introduction

Kawasaki disease is an acute necrotising vasculitis of the medium- and small-sized vessels, occurring mainly in Japanese and Korean babies and children, aged 6 months to 5 years. Its main complication is damage of coronary arteries, which has the potential to be fatal. Here we report a rare case of Kawasaki disease that occurred in a 20-year-old Greek adult.

Case presentation

A 20-year-old Greek man presented with high fever, appetite loss, nausea and vomiting, headache and significant malaise. He had an erythema of the palms and strikingly red lips and conjunctiva. As he did not respond to broad-spectrum antibiotics and after having excluded other possible diagnoses, the diagnosis of Kawasaki disease was set. He was treated with intravenous immunoglobulin and oral aspirin on the 10th day since the onset of the illness. His clinico-laboratory response was excellent and no coronary artery aneurysms were detected in coronary artery computed tomography performed 1 month later.

Conclusions

This report of an adult case of European Kawasaki disease may be of benefit to physicians of various specialties, including primary care doctors, hospital internists, intensivists and cardiologists. It demonstrates that a case of prolonged fever, unresponsive to antibiotics, in the absence of other diagnoses may be an incident of Kawasaki disease. It is worth stressing that such a diagnosis should be considered, even if the patient is adult and not of Asian lineage.

Genetic variants of CD209 associated with Kawasaki disease susceptibility

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Intravenous immunoglobulin-induced IL-33 is insufficient to mediate basophil expansion in autoimmune patients

Intravenous immunoglobulin (IVIg) is used in the therapy of various autoimmune and inflammatory diseases. Recent studies in experimental models propose that anti-inflammatory effects of IVIg are mainly mediated by α2,6-sialylated Fc fragments. These reports further suggest that α2,6-sialylated Fc fragments interact with DC-SIGN⁺ cells to release IL-33 that subsequently expands IL-4-producing basophils. However, translational insights on these observations are lacking. Here we show that IVIg therapy in rheumatic patients leads to significant raise in plasma IL-33. However, IL-33 was not contributed by human DC-SIGN⁺ dendritic cells and splenocytes. As IL-33 has been shown to expand basophils, we analyzed the proportion of circulating basophils in these patients following IVIg therapy. In contrast to mice data, IVIg therapy led to basophil expansion only in two patients who also showed increased plasma levels of IL-33. Importantly, the fold-changes in IL-33 and basophils were not correlated and we could hardly detect IL-4 in the plasma following IVIg therapy. Thus, our results indicate that IVIg-induced IL-33 is insufficient to mediate basophil expansion in autoimmune patients. Hence, IL-33 and basophil-mediated anti-inflammatory mechanism proposed for IVIg might not be pertinent in humans.

DC-SIGN gene promoter variants and IVIG treatment response in Kawasaki disease

BACKGROUND

Genetic variants in the inhibiting FcγRIIB mediate anti-inflammatory responses and influence IVIG refractoriness (IVIG-R). However, these variants are rare in Asian and Hispanic populations so other genes in the pathway could be potentially involved. IVIG is ineffective in mice lacking SIGN-R1, a related molecule to human DC-SIGN. Further, DC-SIGN is a known receptor for sialylated Fc, the component responsible for the anti-inflammatory action of IVIG. Thus, we hypothesized that DC-SIGN would also be involved in the pathway of IVIG response in Kawasaki Disease (KD) patients.

FINDINGS

A case-control approach was performed to examine the differential distribution of five single nucleotide polymorphisms (SNPs) in DC-SIGN promoter with IVIG-R among White (158 vs. 62), Asian (64 vs. 12) and Hispanic (55 vs. 20) KD patients. Distinct differences in allele frequency distributions of several variants in the DC-SIGN promoter were observed in the three ethnic groups. Further, Asians with the major allele "A" in rs2287886 were more likely (OR = 1.76, p = 0.04) to be IVIG non-responder, but this allele is a minor allele in other two ethnic groups, where the association was not apparent.

CONCLUSIONS

DC-SIGN can potentially complement the role of FcγRIIB in the anti-inflammatory cascade involved in the IVIG response mechanism.

Understanding the pathogenesis of Kawasaki disease by network and pathway analysis

Kawasaki disease (KD) is a complex disease, leading to the damage of multisystems. The pathogen that triggers this sophisticated disease is still unknown since it was first reported in 1967. To increase our knowledge on the effects of genes in KD, we extracted statistically significant genes so far associated with this mysterious illness from candidate gene studies and genome-wide association studies. These genes contributed to susceptibility to KD, coronary artery lesions, resistance to initial IVIG treatment, incomplete KD, and so on. Gene ontology category and pathways were analyzed for relationships among these statistically significant genes. These genes were represented in a variety of functional categories, including immune response, inflammatory response, and cellular calcium ion homeostasis. They were mainly enriched in the pathway of immune response. We further highlighted the compelling immune pathway of NF-AT signal and leukocyte interactions combined with another transcription factor NF- κ B in the pathogenesis of KD. STRING analysis, a network analysis focusing on protein interactions, validated close contact between these genes and implied the importance of this pathway. This data will contribute to understanding pathogenesis of KD.