Variants of the CD40 gene but not of the CD40L gene are associated with coronary artery calcification in the Diabetes Heart Study (DHS)

Platelets in Vascular Calcification: A Comprehensive Review of Platelet-Derived Extracellular Vesicles, Protein Interactions, Platelet Function Indices, and their Impact on Cellular Crosstalk

Vascular calcification (VC) commonly accompanies the development of atherosclerosis, defined by the accumulation of calcium in the arterial wall, potentially leading to stroke and myocardial infarction. Severe and unevenly distributed calcification poses challenges for interventional procedures, elevating the risks of vascular dissection, acute vascular occlusion, restenosis, and other major adverse cardiovascular events. Platelets promote the development of atherosclerosis by secreting various inflammatory mediators, regulating cell migration, aggregation, adhesion, and initiating and expanding inflammatory responses. There is emerging evidence that platelets play a direct role in VC; however, this novel concept has not yet been critically assessed. This review describes the intricate mechanisms by which platelets promote VC, focusing on three key aspects and the potential opportunities for their therapeutic targeting: extracellular vesicles, platelet-regulatory proteins, and indices related to platelet function.

Co-stimulators CD40-CD40L, a potential immune-therapy target for atherosclerosis: A review

The interaction between CD40 and CD40 ligand (CD40L) a crucial co-stimulatory signal for activating adaptive immune cells, has a noteworthy role in atherosclerosis. It is well-known that atherosclerosis is linked to immune inflammation in blood vessels. In atherosclerotic lesions, there is a multitude of proinflammatory cytokines, adhesion molecules, and collagen, as well as smooth muscle cells, macrophages, and T lymphocytes, particularly the binding of CD40 and CD40L. Therefore, research on inhibiting the CD40-CD40L system to prevent atherosclerosis has been ongoing for more than 30 years. However, it's essential to note that long-term direct suppression of CD40 or CD40L could potentially result in immunosuppression, emphasizing the critical role of the CD40-CD40L system in atherosclerosis. Thus, specifically targeting the CD40-CD40L interaction on particular cell types or their downstream signaling pathways may be a robust strategy for mitigating atherosclerosis, reducing potential side effects. This review aims to summarize the potential utility of the CD40-CD40L system as a viable therapeutic target for atherosclerosis.

CD40 polymorphisms were associated with HCV infection susceptibility among Chinese population

Background

CD40, encoded by TNFRSF5, participates in the survival of B cells, process of antigen presentation and generation of CD8+ T cell memory. It also has an important effect on HCV antiviral immune response. This study aims to investigate whether TNFRSF5 gene polymorphisms are associated with HCV infection outcomes among Chinese population.

Methods

Three single nucleotide polymorphism (SNPs) (rs1535045, rs1883832, rs4810485) on TNFRSF5 were genotyped by TaqMan assay among Chinese population, including 1513 uninfected subjects, 496 spontaneous viral clearance subjects and 768 persistent HCV-infected subjects. Logistic analysis was used to compare these SNPs among different groups in this cross-sectional study. Functional annotations of the identified SNPs were further evaluated by bioinformatics analysis.

Results

After adjusted by age, gender and routes of infection, the results of logistic analysis indicated that individuals carrying rs1535045 T allele had a higher risk to infect HCV compared with C allele (in recessive model, adjusted OR = 1.368, 95%CI = 1.070-1.749, P = 0.012). Subjects carried rs1535045 TT genotype were more likely to infect HCV than wild CC genotype (adjusted OR = 1.397, 95%CI = 1.078-1.809, P = 0.011). For rs1883832, T allele was significantly associated with an increased risk of HCV infection (in recessive model, adjusted OR = 1.337, 95%CI = 1.069-1.673, P = 0.011). Subjects with TT genotype had more possibility to infect HCV (adjusted OR = 1.351, 95%CI = 1.060-1.702, P = 0.015). In the stratified analysis, rs1535045 and rs1883832 were remained in various subgroups and the heterogeneity test showed no pronounced heterogeneity in any pairwise comparison (all P > 0.05). In addition, the results of the cumulative effects showed a tendency of that the more risk alleles (rs1535045 T and rs1883832 T) subjects carried, the more possibility of HCV infection exhibited (P<0.001). In haplotype analyses, compared with the CC haplotype, CT, TC and TT was correlated with an increased risk to infect HCV (P = 0.029, P = 0.047 and P<0.001, respectively).

Conclusions

In conclusion, CD40 polymorphisms were significantly associated with the susceptibility to HCV among Chinese populations.

Analysis of Genetic Variation in CD40 and CD40L: Relationship with mRNA Relative Expression and Soluble Proteins in Acute Coronary Syndrome

Acute coronary syndrome (ACS) can be triggered by the presence of inflammatory factors which promote the activation of immune cells by costimulatory molecules such as CD40 and its ligand CD40L. Environmental and genetic factors are involved in the etiology of the ACS. The aim of this study was to explore the gene and protein expression associated with CD40 and CD40L genetic variants in ACS patients from the western Mexican population. A total of 620 individuals from western Mexico were recruited: 320 ACS patients and 300 individuals without a history of ischemic cardiopathy were evaluated. The genotype was determined using TaqMan SNP genotyping assays. CD40 and CD40L expressions at the mRNA level were quantified using TaqMan Gene Expression Assays. Soluble protein isoforms were measured by enzyme-linked immunosorbent assay. We did not find evidence of association between CD40 (rs1883832, rs4810485, and rs11086998) and CD40L (rs3092952 and rs3092920) genetic variants and susceptibility to ACS, although rs1883832 and rs4810485 were significantly associated with high sCD40 plasma levels. Plasma levels of sCD40L can be affected by gender and the clinical spectrum of acute coronary syndrome. Our results do not suggest a functional role of CD40 and CD40L genetic variants in ACS. However, they could reflect the inflammatory process and platelet activation in ACS patients, even when they are under pharmacological therapy. Due to the important roles of the CD40-CD40L system in the pathogenesis of ACS, longitudinal studies are required to determine if soluble levels of CD40 and CD40L could be clinically useful markers of a recurrent cardiovascular event after an ACS.

CD40L and Its Receptors in Atherothrombosis-An Update

CD40L (CD154), a member of the tumor necrosis factor superfamily, is a co-stimulatory molecule that was first discovered on activated T cells. Beyond its fundamental role in adaptive immunity-ligation of CD40L to its receptor CD40 is a prerequisite for B cell activation and antibody production-evidence from more than two decades has expanded our understanding of CD40L as a powerful modulator of inflammatory pathways. Although inhibition of CD40L with neutralizing antibodies has induced life-threatening side effects in clinical trials, the discovery of cell-specific effects and novel receptors with distinct functional consequences has opened a new path for therapies that specifically target detrimental properties of CD40L. Here, we carefully evaluate the signaling network of CD40L by gene enrichment analysis and its cell-specific expression, and thoroughly discuss its role in cardiovascular pathologies with a specific emphasis on atherosclerotic and thrombotic disease.

A SNP in 5' untranslated region of CD40 gene is associated with an increased risk of ischemic stroke in a Chinese population: a case-control study

Cluster of differentiation 40 (CD40), the receptor for CD154, is a member of the tumor necrosis factor (TNF) receptor superfamily. Several studies have been conducted to investigate the effect of the CD40 rs1883832 polymorphism on atherosclerotic disease in different population; however, inconsistent results were obtained. In this study, we investigated the association of four polymorphisms (rs1883832, rs13040307, rs752118 and rs3765459) of CD40 gene and their effect on CD40 expression with the risk of ischemic stroke (IS) in a Chinese population. Three hundred and eighty patients with IS and 450 control subjects were included in the study. The CD40 polymorphisms were discriminated by Snapshot SNP genotyping assay. Serum soluble CD40 (sCD40) levels were detected by ELISA. We found that the rs1883832CT and rs1883832TT genotypes were associated with an increased risk of IS compared with the rs1883832CC genotype (OR = 1.42, 95% CI: 1.03–1.95, p = 0.030 and OR = 1.91, 95% CI: 1.29–2.82, P = 0.001, respectively), and the rs1883832T allele was associated with a significantly increased risk of IS compared with rs1883832C allele (OR = 1.40, 95% CI: 1.15–1.70, P = 0.001). Elevated serum sCD40 levels were observed in patients with IS compared with the control gropu (P < 0.01). Individuals carrying the rs1883832TT or rs1883832CT genotypes showed significantly higher sCD40 levels compared with the rs1883832CC genotype in the IS group [(64.8 ± 25.4 pg/mL, TT = 94); (63.9 ± 24.3 pg/mL, CT = 185) vs (53.3 ± 22.5 pg/mL, CC = 101), P < 0.01]. The TCCA haplotype was associated with an increased risk of IS compared with the control group (OR = 2.10, 95% CI: 1.23–3.58, p = 0.005). However, we did not find a significant association between the other three polymorphisms and IS risk. In conclusion, after a comprehensive comparison with other studies, we confirmed that the rs1883832T allele but not the rs1883832C allele is associated with an increased risk of IS. The rs1883832 polymorphism may exert influences on abnormal CD40 expression in IS patients among the Chinese population.

Levels of human platelet-derived soluble CD40 ligand depend on haplotypes of CD40LG-CD40-ITGA2

Increased circulating soluble CD40 ligand (sCD40L) is commonly associated with inflammatory disorders. We aimed to investigate whether gene polymorphisms in CD40LG, CD40 and ITGA2 are associated with a propensity to secrete sCD40L; thus, we examined this issue at the level of human platelets, the principal source of sCD40L. We performed single polymorphism and haplotype analyses to test for the effect of twelve polymorphisms across the CD40LG, CD40 and ITGA2 genes in blood donors. ITGA2 presented a positive association with rs1126643, with a significant modification in sCD40L secretion (carriers of C allele, P = 0.02), unlike the investigated CD40LG and CD40 polymorphisms. One CD40LG haplotype (TGGC) showing rs975379 (C/T), rs3092952 (A/G), rs3092933 (A/G) and rs3092929 (A/C) was associated with increased sCD40L levels (1.906 μg/L (95% CI: 1.060 to 2.751); P = 0.000009). The sCD40L level was associated with the inter-chromosomal CD40LG/CD40/ITGA2 haplotype (ATC), displaying rs3092952 (A/G), rs1883832 (C/T) and rs1126643 (C/T), with increased sCD40L levels (P = 0.0135). Our results help to decipher the genetic role of CD40LG, CD40 and ITGA2 with regard to sCD40L levels found in platelet components. Given the crucial role of sCD40L, this haplotype study in a transfusion model may be helpful to further determine the role of haplotypes in inflammatory clinical settings.

Development of a highly resolutive method, using a double quadruplex tetra-primer-ARMS-PCR coupled with capillary electrophoresis to study CD40LG polymorphisms

Polymorphisms in the CD40 ligand gene (CD40LG) are associated with various immunological disorders such as tumors, autoimmune and infectious diseases. The aim of this study was to develop a highly optimized double quadruplex tetra-primer amplification refractory mutation system PCR (double quadruplex T-ARMS-PCR) coupled with capillary electrophoresis to allow genotyping of eight relevant candidate CD40LG SNPs and to establish haplotypes. After conducting the double quadruplex T-ARMS-PCR, the genotypes obtained through agarose electrophoresis were compared with those obtained through capillary electrophoresis. This strategy was applied to analyze the genetic patterns of CD40LG in two distinct cohorts of blood donors (211 French and 274 Tunisian). The T-ARMS-PCR method was rapid, inexpensive, reproducible and reliable for SNP determination. Regarding the separation technique, capillary electrophoresis allows traceable and semi-automated analysis while agarose electrophoresis remains a cost-effective technique that does not require specialized or costly equipment. Using these methods, we identified significantly different genetic heterogeneity between the two investigated populations (p ≤ 0.0001) and we also extensively characterized their haplotypes. The obtained genotype distribution and the optimized quadruplex T-ARMS-PCR technique coupled with capillary electrophoresis provides valuable information for studying pathologic inflammation leading to various diseases in which CD40LG might be a candidate gene.

Pharmacogenomics of estrogens on changes in carotid artery intima-medial thickness and coronary arterial calcification: Kronos Early Estrogen Prevention Study

Prior to the initiation of menopausal hormone treatment (MHT), genetic variations in the innate immunity pathway were found to be associated with carotid artery intima-medial thickness (CIMT) and coronary arterial calcification (CAC) in women (n = 606) enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). Whether MHT might affect these associations is unknown. The association of treatment outcomes with variation in the same 764 candidate genes was evaluated in the same KEEPS participants 4 yr after randomization to either oral conjugated equine estrogens (0.45 mg/day), transdermal 17β-estradiol (50 μg/day), each with progesterone (200 mg/day) for 12 days each month, or placebo pills and patch. Twenty SNPs within the innate immunity pathway most related with CIMT after 4 yr were not among those associated with CIMT prior to MHT. In 403 women who completed the study in their assigned treatment group, single nucleotide polymorphisms (SNPs) within the innate immunity pathway were found to alter the treatment effect on 4 yr change in CIMT (i.e., significant interaction between treatment and genetic variation in the innate immunity pathway; P < 0.001). No SNPs by treatment effects were observed with changes of CAC >5 Agatston units after 4 yr. Results of this study suggest that hormonal status may interact with genetic variants to influence cardiovascular phenotypes, specifically, the pharmacogenomic effects within the innate immunity pathway for CIMT.

Association of CD40 polymorphisms and haplotype with risk of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease that is caused by genetic and environmental factors. Current evidence shows that the CD40-CD40L system plays a crucial role in the development, progression and outcome of SLE. CD40, which stimulates lymphocyte proliferation and differentiation, is an important immunomodulator and is expressed in the thyroid follicular cells as well as antigen-presenting cells. The aim of the present study was to investigate whether CD40 gene polymorphism confers susceptibility to SLE and its impact on CD40 expression in Chinese. We analyzed four single nucleotide polymorphisms of CD40 gene rs1883832C/T, rs13040307C/T, rs752118C/T, and rs3765459G/A in 205 patients with SLE and 220 age- and sex-matched controls, using Snapshot SNP genotyping assays and DNA sequencing method. Soluble CD40 (sCD40) levels were measured by ELISA. There were significant differences in the genotype and allele frequencies of CD40 gene rs1883832 C/T polymorphism between the group of patients with SLE and the control group (P < 0.05). sCD40 levels were increased in patients with SLE compared with controls (P < 0.01). Moreover, genotypes carrying the CD40 rs1883832 T variant allele were associated with increased CD40 levels compared with the homozygous wild-type genotype in patients with SLE. The rs1883832 C/T polymorphism of CD40 and its sCD40 levels were associated with SLE in the Chinese population. These data suggest that CD40 gene may play an essential role in the development of SLE.

Genetics of cardiovascular disease: Importance of sex and ethnicity

Sex differences in incidence and prevalence of and morbidity and mortality from cardiovascular disease are well documented. However, many studies examining the genetic basis for cardiovascular disease fail to consider sex as a variable in the study design, in part, because there is an inherent difficulty in studying the contribution of the sex chromosomes in women due to X chromosome inactivation. This paper will provide general background on the X and Y chromosomes (including gene content, the pseudoautosomal regions, and X chromosome inactivation), discuss how sex chromosomes have been ignored in Genome-wide Association Studies (GWAS) of cardiovascular diseases, and discuss genetics influencing development of cardiovascular risk factors and atherosclerosis with particular attention to carotid intima-medial thickness, and coronary arterial calcification based on sex-specific studies. In addition, a brief discussion of how ethnicity and hormonal status act as confounding variables in sex-based analysis will be considered along with methods for statistical analysis to account for sex in cardiovascular disease.

Association of systemic inflammation with epicardial fat and coronary artery calcification

BACKGROUND

Increased epicardial fat volume (EFV) has been shown to be associated with coronary atherosclerosis. While it is postulated to be an independent risk factor, a possible mechanism is local or systemic inflammation. We analyzed the relationship between coronary atherosclerosis, quantified by coronary calcium in CT, epicardial fat volume and systemic inflammation.

METHODS

Using non-enhanced dual-source CT, we quantified epicardial fat volume (EFV) and coronary artery calcium (CAC) in 391 patients who underwent coronary computed tomography for suspected coronary artery disease. In addition to traditional risk factors, serum markers of systemic inflammation were measured (IL-1α, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10,IL-12, IL-13, IL-15, IL-17, IFN-γ, TNF-α, hs-CRP, GM-CS, G-CSF, MCP-1, MIP-1, Eotaxin and IP-10). In 94 patients follow-up data were obtained after 1.9 ± 0.5 years.

RESULTS

The 391 patients had a mean age of 60 ± 10 years, and 69 % were males. Mean EFV was 116 ± 50 mL. Median CAC was 12 (IQR 0; 152). CAC and EFV showed a significant correlation (ρ = 0.37; P < 0.001). EFV and CAC were significantly correlated with the traditional risk factors like age, male gender, diabetes, smoking and hypertension. With regard to biomarkers, CAC was significantly associated (negatively) to G-CSF and IL-13. EFV (median binned) was significantly associated (positively) with IP-10 (P = 0.002) and MCP-1 (ρ = 0.037). In follow-up, EFV showed a mean annualized progression of 6 mL (IQR 3; 9) (P < 0.001); CAC progressed by a mean of six Agatston Units (IQR 0; 30). The progression of CAC was significantly correlated with the extent of EFV (P < 0.001) while there was no significant correlation between progression of EFV or CAC with systemic inflammation markers.

CONCLUSION

Epicardial fat volume and the baseline extent as well as progression of coronary atherosclerosis-measured by the calcium score-are significantly correlated. While both baseline EFV and CAC displayed significant correlations with systemic inflammation markers, biomarkers were not predictive of the progression of CAC or EFV.

The SNP rs1883832 in CD40 gene and risk of atherosclerosis in Chinese population: a meta-analysis

Background

The complications of atherosclerosis such as coronary and cerebrovascular disease, are the most prevalent causes of mortality and morbidity worldwide. A single nucleotide polymorphism (SNP) rs1883832 (-1C/T) in CD40 gene has been recently suggested to contribute to the susceptibility to atherosclerosis in Chinese population; however, previous genetic association studies yielded inconsistent results.

Methods

A meta-analysis of eligible studies reporting the association between rs1883832 and atherosclerosis in Chinese population was carried out.

Results

Pooling 7 eligible case-control studies involving 2129 patients and 1895 controls demonstrated a significant association between rs1883832 and atherosclerosis under dominant model [odds ratio (OR) = 1.631, 95% confidence interval [CI] [1.176, 2.260] in Chinese population with evident heterogeneity. Meta-regression analysis indicated that the heterogeneity could be completely explained by disease category. In subgroup analysis, rs1883832 conferred ORs of 2.866 (C/C versus T/T, 95%CI [2.203, 3.729]) and 1.680 (C/T versus T/T, 95%CI [1.352, 2.086]) for coronary artery disease (CAD) under co-dominant model without heterogeneity. Similar results were obtained for acute coronary syndrome (ACS) (C/C versus T/T, 3.674, 95%CI [2.638, 5.116]; C/T versus T/T, 1.981, 95%CI [1.483, 2.646]). The other genetic models including dominant, recessive and additive models, yielded consistent results without heterogeneity for CAD and ACS, respectively. However, a protective role was found for C allele in ischemic stroke (IS) under recessive model (0.582, 95%CI [0.393, 0.864]) and additive model (0.785, 95%CI [0.679, 0.909]) with reduced heterogeneity.

Conclusions

This meta-analysis provided evidence of association of rs1883832 C allele with an overall increased risk of atherosclerosis but distinct effect of C allele on CAD (including ACS) and IS in Chinese population, respectively.

Single nucleotide polymorphism of CD40 in the 5'-untranslated region is associated with ischemic stroke

OBJECTIVES

Ischemic stroke is influenced by both environmental and genetic factors. The CD40/CD40L system is related to proinflammatory and prothrombogenic responses, which are involved in the pathophysiology of ischemic stroke. The aim of this study was to evaluate association between the CD40 -1C/T single nucleotide polymorphism (SNP) and ischemic stroke in a Chinese population.

METHODS

We conducted a case-control study including 286 ischemic stroke patients and 336 controls. CD40 -1C/T SNP was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing methods, and evaluated its relevance to ischemic stroke susceptibility.

RESULTS

Significantly increased ischemic stroke risk was found to be associated with the T allele of CD40 -1C/T (OR=1.273, 95% CI=1.016-1.594). The frequencies of CT and TT/CT genotypes of CD40 -1C/T in ischemic stroke patients were significantly higher than those of controls, respectively (for CT: OR=2.350, 95% CI=1.601-3.449; for TT/CT: OR=2.148, 95% CI=1.479-3.119). And, similar results were obtained after adjusting non-matched variables. We found that the frequency of carried T genotypes (TT and TT/CT) was significantly increased in patients with history of stroke compared with patients without (for TT: OR=6.538, 95%CI=1.655-25.833; for TT/CT: OR=3.469, 95%CI=1.031-11.670), respectively.

CONCLUSIONS

The findings suggested that the CD40 -1C/T polymorphism might contribute to the susceptibility to ischemic stroke in the Chinese population, and might be associated with history of previous stroke.

Single nucleotide polymorphism of CD40 region and the risk of systemic lupus erythematosus

There is one study on the association of the CD40 G > T (rs4810485) single nucleotide polymorphism (SNP) as a risk factor of systemic lupus erythematosus (SLE). Therefore, we studied the prevalence of the CD40 G > T SNP in patients with SLE ( n = 261) and controls ( n = 545) in a Polish population. We did not find significant differences between the CD40 G > T genotype and allele frequency in patients with SLE and healthy individuals. However, the frequency of the CD40 TT and GT genotypes was statistically different between patients with arthritis and neurologic manifestations and patients without these symptoms (OR = 0.2009 (95% CI = 0.07547–0.5348, p = 0.0004, pcorr = 0.0068) and OR = 0.2876 (95% CI = 0.1371–0.6031, p = 0.0005, pcorr = 0.0085) respectively). Our observations indicate that the CD40 T variant might be negatively associated with some clinical disease manifestations in patients with SLE.

Study of association of CD40-CD154 gene polymorphisms with disease susceptibility and cardiovascular risk in Spanish rheumatoid arthritis patients

Objective

Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with increased cardiovascular (CV) mortality. Since CD40-CD154 binding has direct consequences on inflammation process initiation, we aimed to replicate previous findings related to disease susceptibility in Spanish RA population. Furthermore, as the major complication in RA disease patients is the development of CV events due to accelerated atherosclerosis, and elevated levels of CD40L/CD154 are present in patients with acute myocardial infarction, we assessed the potential association of CD40 and CD154/CD40L gene variants with CV risk in Spanish RA patients.

Methods

One thousand five hundred and seventy-five patients fulfilling the 1987 ACR classification criteria for RA and 1600 matched controls were genotyped for the CD40 rs1883832, rs4810485 and rs1535045 and CD154 rs3092952 and rs3092920 gene polymorphisms, using predesigned TaqMan single nucleotide polymorphism genotyping assays. Afterwards, we investigated the influence of CD40-CD154 gene variants in the development of CV events. Also, in a subgroup of 273 patients without history of CV events, we assessed the influence of these polymorphisms in the risk of subclinical atherosclerosis determined by carotid ultrasonography.

Results

Nominally significant differences in the allele frequencies for the rs1883832 CD40 gene polymorphism between RA patients and controls were found (p = 0.038). Although we did not observe a significant association of CD40-CD154 gene variants with the development of CV events, an ANCOVA model adjusted for sex, age at the time of the ultrasonography assessment, follow-up time, traditional CV risk factors and anti-cyclic citrullinated peptide antibodies disclosed a significant association (p = 0.0047) between CD40 rs1535045 polymorphism and carotid intima media thickness, a surrogate marker of atherosclerosis.

Conclusion

Data from our pilot study indicate a potential association of rs1883832 CD40 gene polymorphism with susceptibility to RA. Also, the CD40 rs1535045 gene variant may influence development of subclinical atherosclerosis in RA patients.

Analysis of the association between CD40 and CD40 ligand polymorphisms and systemic sclerosis

Introduction

The aim of the present study was to investigate the possible role of CD40 and CD40 ligand (CD40LG) genes in the susceptibility and phenotype expression of systemic sclerosis (SSc).

Methods

In total, 2,670 SSc patients and 3,245 healthy individuals from four European populations (Spain, Germany, The Netherlands, and Italy) were included in the study. Five single-nucleotide polymorphisms (SNPs) of CD40 (rs1883832, rs4810485, rs1535045) and CD40LG (rs3092952, rs3092920) were genotyped by using a predesigned TaqMan allele-discrimination assay technology. Meta-analysis was assessed to determine whether an association exists between the genetic variants and SSc or its main clinical subtypes.

Results

No evidence of association between CD40 and CD40LG genes variants and susceptibility to SSc was observed. Similarly, no significant statistical differences were observed when SSc patients were stratified by the clinical subtypes, the serologic features, and pulmonary fibrosis.

Conclusions

Our results do not suggest an important role of CD40 and CD40LG gene polymorphisms in the susceptibility to or clinical expression of SSc.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Polymorphisms of the Genes EncodingCD40and Growth Differentiation Factor 15 and in the 9p21.3 Region in Patients with Rheumatoid Arthritis and Cardiovascular Disease

Objective.

Genes or gene products associated with coronary artery disease in the general population were analyzed in rheumatoid arthritis (RA) patients with atherothrombotic manifestations (ATM).

Methods.

A cross-sectional study of 681 individuals (498 women; 183 men) with RA (American College of Rheumatology criteria), a mean age of 60.6 ± 13.2 years, and mean disease duration of 15.5 ± 12.6 years who were consecutively recruited and followed for 6 years. The prevalence of ATM [i.e., myocardial infarction, angina pectoris with intervention, deep vein thrombosis/pulmonary embolism (DVT/PE), and/or stroke/transient ischemic attack (TIA)] was recorded. Polymorphisms were analyzed in the genes coding for growth differentiation factor 15 (GDF15)/monocyte inhibitory cytokine-1 (MIC-1; rs1058587),CD40(rs1535045 and rs3765459), and the 9p21.3 locus (rs1333049). Controls were randomly selected (n = 687; matched for age and sex).

Results.

The distribution of genotypes ofGDF15/MIC-1differed significantly between patients with RA and controls (chi-squared = 6.40, 2 df, p = 0.041). ATM were associated with polymorphism of theGDF15/MIC-1G allele (OR 2.21, 95% CI 1.17–4.18), and with CC genotype of the 9p21.3 locus (rs1333049; OR 1.92, 95% CI 1.15–3.19). Stroke/TIA in women was associated withGDF15/MIC-1GG genotype (OR 3.75, 95% CI 1.06–13.33), while stroke/TIA in men was associated withCD40homozygous major alleles (OR 6.48, 95% CI 1.31–32.0 and OR 2.78, 95% CI 0.78–9.91, respectively). DVT/PE was associated with polymorphism in theGDF15/MIC-1gene (rs1058587) minor allele (OR 3.53, 95% CI 1.30–9.58).

Conclusion.

The gene polymorphisms analyzed were associated with different ATM in RA. TheGDF15/MIC-1gene polymorphism was also associated with RAper se, suggesting a common etiology for RA and ATM.

Association of systemic inflammation markers with the presence and extent of coronary artery calcification

BACKGROUND

Coronary artery calcification (CAC) is a marker for the presence and extent of coronary atherosclerotic plaques and can be detected non-invasively by multi-detector row CT (MDCT). Well known predictors of CAC are age, gender, and the classical atherogenic risk factors. CAC is associated with atherosclerotic plaque burden, but it is still elusive if atherosclerosis-relevant cytokines and chemokines are also associated with CAC.

METHODS

We conducted a clinical study among 455 consecutive individuals who underwent coronary calcium assessment performed by MDCT. Before MDCT, blood was drawn and subsequently analyzed for 20 different atherosclerosis-relevant cytokines and chemokines using a Luminex-laser-based fluorescence analysis.

RESULTS

Using univariate analyses, CAC patients revealed significantly higher levels of the chemokines IP-10 (P=0.047) and eotaxin (P=0.031) as compared to non-CAC patients. In multivariate analyses using common thresholds for calcium burden, the three cytokines interleukin-6 (P=0.028), interleukin-8 (P=0.009), and interleukin-13 (P=0.024) were associated with high coronary calcium levels after adjustment for classical variables and risk factors.

CONCLUSIONS

In a large group of individuals with atypical chest pain and a low to intermediate likelihood for coronary artery disease elevated plasma levels of IL-6 and reduced levels of IL-8 and IL-13 were predictive for distinct coronary artery calcification. These findings support a specific role of these cytokines in coronary calcification.

Association of VKORC1 -1639 G>A polymorphism with carotid intima-media thickness in type 2 diabetes mellitus

AIMS

Media calcification is a predictor of cardiovascular mortality in type 2 diabetes mellitus (T2DM). Undercarboxylation of some vitamin K-dependent proteins, due to genetic polymorphisms of VKORC1, can lead to calcification. We examined a potential association between VKORC1 -1639 G>A polymorphism and T2DM and, also, the association of this polymorphism with carotid intima-media thickness (cIMT).

METHODS

VKORC1 -1639 G>A polymorphism was determined in 299 T2DM patients and 328 controls of Caucasian origin using PCR-RFLP. cIMT was measured in a subgroup of 118 T2DM patients.

RESULTS

The frequency of VKORC1 genotypes between diabetic and nondiabetic subjects differed significantly (p=0.01). VKORC1 genotype was associated with T2DM in an adjusted model (OR 1.36, p=0.009). A statistically significant difference was observed in the maximum value of cIMT among different genotypes. VKORC1 -1639 G>A polymorphism was an independent predictor of cIMT (p=0.029) after adjusting for established risk factors.

CONCLUSIONS

The association between VKORC1 -1639 G>A polymorphism and risk of T2DM could be due to the higher prevalence of calcification in T2DM patients. This is supported by the independent association between VKORC1 -1639 G>A polymorphism and maximum cIMT in T2DM patients which is likely due to atherosclerosis characterized by increased calcification.

Platelet activation in patients with atherosclerotic renal artery stenosis undergoing stent revascularization

BACKGROUND AND OBJECTIVES

Soluble CD40 ligand (sCD40L) is a marker of platelet activation; whether platelet activation occurs in the setting of renal artery stenosis and stenting is unknown. Additionally, the effect of embolic protection devices and glycoprotein IIb/IIIa inhibitors on platelet activation during renal artery intervention is unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Plasma levels of sCD40L were measured in healthy controls, patients with atherosclerosis without renal stenosis, and patients with renal artery stenosis before, immediately after, and 24 hours after renal artery stenting.

RESULTS

Soluble CD40L levels were higher in renal artery stenosis patients than normal controls (347.5 ± 27.0 versus 65.2 ± 1.4 pg/ml, P < 0.001), but were similar to patients with atherosclerosis without renal artery stenosis. Platelet-rich emboli were captured in 26% (9 of 35) of embolic protection device patients, and in these patients sCD40L was elevated before the procedure. Embolic protection device use was associated with a nonsignificant increase in sCD40L, whereas sCD40L declined with abciximab after the procedure (324.9 ± 42.5 versus 188.7 ± 31.0 pg/ml, P = 0.003) and at 24 hours.

CONCLUSIONS

Atherosclerotic renal artery stenosis is associated with platelet activation, but this appears to be related to atherosclerosis, not renal artery stenosis specifically. Embolization of platelet-rich thrombi is common in renal artery stenting and is inhibited with abciximab.

Soluble CD40 ligand is elevated in type 1 diabetic nephropathy but not predictive of mortality, cardiovascular events or kidney function

Soluble CD40 ligand (sCD40L) derived from platelets mediates atherothrombosis, leading to proinflammatory and proatherosclerotic responses. We investigated the predictive value of plasma sCD40L for all-cause mortality, cardiovascular mortality and morbidity, progression towards end-stage renal disease (ESRD) and rate of decline in glomerular filtration rate (GFR) in patients with type 1 diabetes (T1DM) and nephropathy. The study was a prospective, observational follow-up study of 443 T1DM patients with diabetic nephropathy (274 men; age 42.1 ± 10.5 years [mean ± SD], duration of diabetes 28.3 ± 8.9 years, GFR 76 ± 33 ml/min/1.73 m2) and a control group of 421 patients with longstanding type 1 diabetes and persistent normoalbuminuria (232 men; age 45.4 ± 11.5 years, duration of diabetes 27.7 ± 10.1 years) at baseline. sCD40L was measured by ELISA. Plasma sCD40L levels were higher in patients with diabetic nephropathy compared to normoalbuminuric patients (median (range) 1.54 (0.02-13.38) vs. 1.30 (0.04-20.65) µg/L, respectively p = 0.004). The patients were followed for 8.1 (0.0-12.9) years (median (range)). Among normoalbuminuric patients, sCD40L levels did not predict all-cause mortality (p = 0.33) or combined fatal and non-fatal cardiovascular disease (CVD) (p = 0.27). Similarly, among patients with diabetic nephropathy, the covariate adjusted sCD40L levels did not predict all-cause mortality (p = 0.86) or risk of fatal and non-fatal CVD (p = 0.08). Furthermore, high levels of sCD40L did not predict development of ESRD (p = 0.85) nor rate of decline in GFR (p = 0.69). Plasma sCD40L is elevated in T1DM nephropathy but is not a predictor of all-cause mortality, cardiovascular mortality and morbidity or deterioration of kidney function

The genetics of vascular complications in diabetes mellitus

Prospective identification of which individuals with diabetes mellitus (DM) are at greatest risk for developing cardiovascular disease (CVD) complications would have considerable public health importance by allowing the allocation of limited resources to be focused on those individuals who would most benefit from aggressive intervention. Over the past 20 years genetic disease association studies have demonstrated that polymorphisms at specific genetic loci may identify those individuals at greatest risk for developing CVD in the setting of DM. This article reviews the evidence accumulated to date on four polymorphic loci with the aim of explaining how these polymorphisms modify the risk for CVD in DM by modifying the functional activity of a specific gene. Use of the knowledge of these genetic differences among individuals in targeting drug therapy (pharmacogenomics) is also discussed.

CD40-1C>T polymorphism (rs1883832) is associated with brain vessel reocclusion after fibrinolysis in ischemic stroke

AIMS

To find genetic predictors of reocclusion after successful fibrinolytic therapy during the acute phase of ischemic stroke.

PATIENTS & METHODS

This was a case-case prospective study analyzing 236 polymorphisms in a cohort of 222 patients treated with tissue plasminogen activator, from which 16 patients suffered a reocclusion event (7.2%). A predictive scale was generated using independent polymorphisms with a dominant/recessive model and tandem occlusion, weighted by their beta-coefficients in logistic regression.

RESULTS

Using a dominant/recessive model, the rs1800801 SNP from the MGP gene (odds ratio [OR]: 15.25; 95% CI: 2.23-104.46; adjusted p = 0.006) and the rs1883832 SNP from CD40 gene (OR: 0.077; 95% CI: 0.009-0.66; adjusted p = 0.019) were independently associated with reocclusion after logistic regression adjustment by clinical predictors. In an additive model, only the rs1883832 SNP (OR: 4.43; 95% CI: 1.62-12.15; adjusted p = 0.004) was related to reocclusion occurrence. The predictive model that was generated stratified the reocclusion risk from less than 1% to more than 70%. Reocclusions were associated with neurological worsening at 24 h (patients with reocclusion: 26.7%, versus patients without reocclusion: 4.9%; p = 0.002), as it was seen for MGP -7A>G (AA: 17.2% vs AG+GG: 4.5%; p = 0.027), but not for CD40 1C>T (CC: 4.5% vs CT+TT: 7.7%; p = 0.565). There was an association between CD40 -1C>T genotype and CD40 transcriptional activity in peripheral blood mononuclear cells (median expression values TT: 65.75%, CT: 70.80%, CC: 96.00%; p = 0.023). However, CD40 soluble fraction was not a useful biomarker of reocclusion status.

CONCLUSION

An association was found between MGP -7A>G and CD40 -1C>T polymorphisms, and reocclusion risk. The predictive scale that was generated permits the stratification of patients by their reocclusion risk with higher accuracy than clinical parameters alone.

Pathogen-mediated inflammatory atherosclerosis is mediated in part via Toll-like receptor 2-induced inflammatory responses

Studies in humans have established that polymorphisms in genes encoding the innate immune Toll-like receptors (TLRs) are associated with inflammatory atherosclerosis. In hyperlipidemic mice, TLR2 and TLR4 have been reported to contribute to atherosclerosis progression. Human and mouse studies support a role for the oral pathogen Porphyromonas gingivalis in atherosclerosis, although the mechanisms by which this pathogen stimulates inflammatory atherosclerosis via innate immune system activation is not known. Using a genetically defined apolipoprotein E-deficient (ApoE(-/-)) mouse model we demonstrate that pathogen-mediated inflammatory atherosclerosis occurs via both TLR2-dependent and TLR2-independent mechanisms. P. gingivalis infection in mice possessing functional TLR2 induced the accumulation of macrophages as well as inflammatory mediators including CD40, IFN-gamma and the pro-inflammatory cytokines IL-1 beta, IL-6 and tumor necrosis factor-alpha in atherosclerotic lesions. The expression of these inflammatory mediators was reduced in atherosclerotic lesions from P. gingivalis-infected TLR2-deficient (TLR2(-/-)) mice. These studies provide a mechanistic link between an innate immune receptor and pathogen-accelerated atherosclerosis by a clinically and biologically relevant bacterial pathogen.

Proinflammatory and atherogenic activity of monocytes in type 2 diabetes

Cytokines secreted by the monocyte-macrophage system play a key role in the progression of atherosclerotic lesions in Type 2 diabetes. The objectives of this study were to assess the influence of cytokine gene expression in monocytes from patients with Type 2 diabetes on direct markers of endothelial injury with regard to clinically manifest atherosclerosis.

METHODS

Monocytes from 58 patients with Type 2 diabetes and from 22 age-matched healthy volunteers of a control group were isolated in order to assess expression of tumor necrosis factor alpha (TNFalpha), interleukin (IL)-6, IL-8 and IL-10 cytokines (RTPCR, Applied Biosystems). Thrombomodulin concentration was determined using a Diagnostica Stago Immunoenzymatic assay, and circulating endothelial cell numbers were assayed using immunofluorescence studies with CLB-HEC19 antibodies.

RESULTS

In 28 patients, TNFalpha expression in monocytes was observed. In these patients, as compared to those with undetectable levels of this cytokine's expression, higher hemoglobin A(1c) (P=.012) and thrombomodulin (P=.005) concentrations were found. IL-8 expression was determined in 36 patients. Higher expression of TNFalpha (P=.048) and IL-8 (P=.049) was detected in patients with peripheral arterial disease in contrast to those free from this complication.

CONCLUSION

TNFalpha and IL-8 play a significant role in the proatherogenic activity of monocytes in Type 2 diabetes. The TNFalpha-connected activity of monocytes may directly determine endothelial dysfunction and injury. The location of atherosclerosis should be taken into account in the assessment of the proinflammatory activity of peripheral blood monocytes.

STAT2*C related genotypes and allele but not TLR4 and CD40 gene polymorphisms are associated with higher susceptibility for asthma

Objective: Asthma is caused by a complex interaction between multiple genes and environmental factors. Herein we aimed to investigate whether signal transducer and activator of transcription (STAT2), toll-like receptors 4 (TLRs4) and CD40-related polymorphisms are associated with asthma susceptibility.

Design: Children were divided: (1) asthma (n=117); (2) normal controls (n=60). The polymorphisms of STAT2, TLR4 and CD40 polymorphism were analyzed by PCR-RFLP genotyping. Genotypes, allelic frequencies and association of haplotypes in both groups were compared.

Results: STAT2*C related genotypes, but not TLR4 and CD40 polymorphism, are associated with higher susceptibility for asthma. Distributions of STAT2*CC/CG/GG and C/G allele in both groups are: (1) 0/11.1/88.9 % and 5.6/94.4%; (2) 0/1.7/98.3% and 0.8/99.2% (p<0.05). Proportions of TLR4*rs10983755 AA/AG/GG and rs1927914 CC/CT/TT homozygote are: (1) 35.1/8.5/56.4% and 9.4/56.4/34.2%; (2) 35/8.3/56.7% and 16.7/48.3/35% (non-difference). Proportions of CD40*rs1883832 CC/CT/TT, rs3765459 AA/AG/GG, and rs4810485 TT/GT/GG are: (1) 29.9/53/17.1%, 6.8/47.9/45.3 and 18.8/62.4/18.8%; (2) 36.7/41.7/21.6%, 1.6/46.7/ 51.7 and 15/51.7/33.3% (non-difference). Haplotype analyses for TLR4 and CD40 genes revealed their non-association and non-additional effect upon asthma susceptibilities.

Conclusion: STAT2*C related genotypes and alleles are associated with asthma susceptibilities and pathogenesis. There were non-association and non-additional effects of TLR4/CD40 gene polymorphisms and haplotypes upon asthma risk.

Increased concentrations of soluble CD40 ligand may help to identify type 1 diabetic adolescents and young adults at risk for developing persistent microalbuminuria

BACKGROUND

Recent studies on the pathogenesis of diabetic complications have demonstrated the important role of a number of aberrantly expressed molecules acting together in the development of early diabetic microvascular complications. Soluble CD40 ligand (sCD40L) is supposed to be one of the most likely candidates for both retinopathy and nephropathy.

METHODS

In January 1989, sCD40L was measured in 340 normoalbuminuric diabetic adolescents and young adults. Participants were examined at baseline and biannually thereafter. sCD40L was measured every 2 years during a 16-year follow-up period. sCD40L was also measured in parents.

RESULTS

Over 16 years, 32 out of 340 patients developed persistent microalbuminuria; no patient developed overt diabetic nephropathy. The risk of developing microalbuminuria was higher in children with increased sCD40L at the beginning of the study (using 6 ng/mL as the arbitrary cut-off value) (group A) compared with those with normal sCD40L (group B). Sex did not influence predictive value, sensitivity, or specificity. sCD40L was not significantly correlated with duration of diabetes. The percentage of offspring with both parents having sCD40L above the mean values was significantly higher in group A than in group B. The odds ratio (OR) for the occurrence of microalbuminuria after adjustment for confounding variables in patients with elevated baseline sCD40L was 4.2 (95% CI, 2.1-10.7).

CONCLUSIONS

Persistently increased sCD40L levels from the onset of diabetes might help to identify those normotensive and normoalbuminuric young patients at increased risk of developing incipient nephropathy later in life.

Molecular and functional analysis of a novel recombinant clone of rat (Rattus norvegicus) CD40 ligand (CD40L) gene

Genetic material obtained from various individuals may contain certain polymorphisms which may conflict with the predetermined DNA sequence and consequently, may modulate the function of gene products. In this study, coding sequence of rat CD40 ligand (CD40L, CD154) was obtained from activated splenocytes, amplified, and cloned into a eukaryotic expression vector by using directional cloning method. Sequence of the recombinant rat CD40L DNA, pCD40L-IRES2-EGFP (pCD40L), was compared with the previously reported rat CD40L cDNA sequences and a 99% identity was found. Differing nucleotides were on the positions; 122-T/C, 341-G/A, 476-G/A, 762-T/A. Further alignment analysis showed that pCD40L was collectively carrying the nucleotides each previously reported by different groups. The sequence was submitted to NCBI GenBank and nucleotide database accession number EF066490 was obtained. Following transfection of the construct into NIH/3T3 cell line, novel CD40L clone was functionally expressed de novo, increasing the expression of CD80 and CD86 costimulatory molecules and augmenting the proliferation rate of effector splenocytes in immune reactions ex vivo. Based on these data, here we report a novel recombinant clone of the rat CD40L gene which may represent a potential polymorphic variant.

Noninvasive measures of cardiovascular changes in diabetes mellitus

PURPOSE OF REVIEW

Advances in noninvasive medical technology have led to more aggressive pursuit of cardiovascular disease detection in patients with diabetes mellitus. Studies measuring carotid intima-media thickness, arterial stiffness and coronary artery calcification have documented early markers of cardiovascular disease. Such markers have gained popularity for research and clinical use. This paper reviews recent studies using noninvasive technology for detection and monitoring of cardiovascular disease as it pertains to diabetes patients.

RECENT FINDINGS

Studies published in the review period have utilized noninvasive techniques to monitor subclinical cardiovascular disease in diabetes patients, including carotid intima-media thickness to evaluate carotid atherosclerosis, pulse wave velocity and pulse wave analysis to measure arterial stiffness, electron beam computed tomography to evaluate coronary artery calcification, and magnetic resonance imaging to study cardiovascular plaque. These techniques have shown promising results and will have useful application for diabetes patients in the future.

SUMMARY

Noninvasive testing is being redefined to include new techniques for detection and monitoring of cardiovascular changes. In the appropriate clinical setting, these tests offer novel approaches to monitoring - each with its own benefits and caveats. Further refinement of techniques will lead to increased applicability and improved ability for early detection of subclinical cardiovascular disease.

Thematic review series: Patient-Oriented Research. Imaging atherosclerosis: state of the art

The ability to image obstructive arterial disease brought about a revolution in clinical cardiovascular care; the development of newer technologies that image arterial wall thicknesses, areas, volumes, and composition allows valid imaging of atherosclerosis for the first time. Development of noninvasive imaging of atherosclerosis has further led to a quantum shift in research in the field by enabling the study of asymptomatic populations and thus allowing investigators to focus on preclinical disease without the many biases associated with the study of symptomatic patients. These noninvasive investigations have broad implications for clinical care as well. Coronary angiography, computed tomographic (CT) imaging of coronary calcium, intravascular ultrasound, multidetector CT angiography, B mode ultrasound of the carotid arteries, and MRI of the carotid arteries all have unique strengths and weaknesses for imaging atherosclerosis. Certain of these techniques are extremely useful as outcome variables for clinical trials, and others are uniquely useful as predictors of the risk of cardiovascular disease. All are informative in one way or another with regard to the role of plaque remodeling and composition in disease causation. CT and MRI technology are advancing very rapidly, and research and clinical uses of these imaging modalities promise to further advance our understanding of atherosclerosis and its prevention.