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We compared the immunogenetic data from 2666 patients affected by HLA-related autoimmune diseases with those from 4389 ethnically matched controls (3157 cord blood donors CBD, 1232 adult bone marrow donors BMD), to verify the appropriateness of HLA typing requests received in the past decade. The frequency of HLA-B*27 phenotype was 10.50% in 724 ankylosing spondylitis, 16.80% in 125 uveitis (3.41% BMD, 4.24% CBD,P<0.0001); HLA-B*51 allele was 15.57% in 212 Behçet’s disease (12.91% BMD, 9.88% CBD,P<0.0001); the HLA-DRB1-rheumatoid arthritis (RA) shared epitope was 13.72% in 554 RA (10.85% BMD, 13.48% CBD,P=0.016); the carriers of almost one of HLA-DQB1 susceptibility alleles were 84.91% in 795 celiac disease (CD) and 59.37% in 256 insulin-dependent diabetes mellitus (IDDM) (46.06% in 875 CBD, 42.75% in 662 BMDP<0.0001). Overall, our results show that the HLA marker frequencies were higher in patients than controls, but lower than expected from the literature data (excluding CD and IDDM) and demonstrate that, in complex immunogenetic conditions, a substantial number of genetic analyses are redundant and inappropriate, burdening to the public health costs. For this reason, we suggest the Italian Scientific Society of Immunogenetics to establish guidelines to improve the appropriateness of typing requests.

The HLA genomic structure underlines the permanence of fixed haplotypes transmitted in blocks as allelic combinations. One of the most discussed concerns is how and why such a strong linkage between HLA alleles has been maintained for so long. We hypothesized a possible KIR-driven pressure in the genesis of specific HLA-A,B haplotypes. Certain HLA-A and -B molecules are ligands for the same KIR receptors through the Bw4 binding motif spanning residues 77-83 in the α1 domain. We analyzed the HLA-A and -B genomic types of 9897 Caucasian people (3533 newborns and 6364 adults) subdividing them according to the presence/absence of the HLA-B Bw4 serological epitope. For each HLA-B Bw4- and Bw6-cross-reactive group, we evaluated the presence/absence of HLA-A ligands for KIR3DL1 (HLA-A*23, HLA-A*24, HLA-A*32) and KIR3DL2 (HLA-A*03, HLA-A*11). The frequency of HLA-A KIR ligands significantly increased moving from the HLA-B Bw4/Bw4 to the HLA-B Bw4/Bw6 and the HLA-B Bw6/Bw6 groups among both newborns and adults (P

Inflammation plays a pivotal role in the pathogenesis of atherosclerosis and coronary syndromes. Atherosclerosis is a complex multifactorial disorder. Data indicate that the complement proteins play a crucial role in the link between inflammation and atherogenesis. Thus, there is evidence supporting the role of complement activation in atherogenesis. Complement receptor 1 (CR1) is a membrane protein found on different cells involved in various activities of the complement system. We demonstrated the possible involvement of CR1 in atherosclerosis studying the allele and genotype frequencies of the CR1 Pro1827Arg, CR1 His1208Arg exon 22 and int27 HindIII polymorphisms in a sample of patients with angiographically documented coronary artery disease (CAD) (n=550) and in healthy controls (n=380) matched for age, gender and ethnicity. Our data showed no significant deviations between the two groups with regard to either allele or genotype frequencies. After stratification according to risk factors, our analysis revealed a reduced frequency of the GG genotype of the Pro1827Arg polymorphism in patients with CAD and dyslipidemia vs the controls (p=0.031) and of the GG and LL genotypes in CAD patients with dyslipidemia vs CAD patients without dyslipidemia regarding the Pro1827Arg and CR1 HindIII intron 27 polymorphisms (GG, p=0.019; LL, p=0.184). We analyzed the haplotype frequencies of CR1. A decrease in CAD patients carrying the CAC haplotype compared to controls (p=0.043) and a decrease in the CAC haplotype in CAD patients with hypertension vs healthy controls (p=0.029) were demonstrated. Our data showed a possible involvement of CR1 gene polymorphisms in the predisposition to the development of this disease.

Upregulation of the receptor for advanced glycation end products (RAGE) may play a crucial role in neointimal formation upon vessel injury. The −374T/A variant of the RAGE gene promoter, which has been associated with an altered expression of the cell-surface receptor, could exert a protective effect toward the development of vascular disease. The aim of this study is to determine the impact of this common genetic variant in the occurrence of clinical in-stent restenosis after coronary stent implantation. The −374T/A polymorphism of the RAGE gene promoter was evaluated by PCR-RFLPs in 267 patients with coronary artery disease who underwent coronary stent implantation and a subsequent coronary angiography 6–9 months later for suspected restenosis. In-stent restenosis was assessed by means of quantitative angiography. Carriers of the-374AA genotype showed a significantly reduced risk of developing restenosis after percutaneous transluminal intervention than non-carriers. To determine whether the protective effect of the homozygous AA genotype toward clinical restenosis was independent of potential confounders, we performed multivariable logistic regression analysis. After allowance for clinical and biochemical risk factors and stent length, the AA genotype remained significantly associated with a reduced prevalence of in-stent restenosis. No relation was evident between the RAGE genotype and established cardiovascular risk factors. In conclusion, the −374AA genotype of the RAGE gene promoter could be associated with a reduced risk of in-stent restenosis after coronary stent implantation.

The receptor for advanced glycation end products (RAGE) is thought to play a critical role in diabetic atherosclerosis. Accordingly, a functional -374T/A polymorphism in RAGE gene promoter has been associated with macrovascular complications in type 1 diabetic patients. However, the extent to which this common variant influences the risk of coronary artery disease (CAD) in the general population remains to be determined. We genotyped the -374T/A RAGE polymorphism in 259 non-diabetic individuals, of whom 175 had angiographically documented coronary artery disease (CAD patients) and 84 had normal coronary angiography (CAD-free control subjects). Homozygosity for the -374A allele was found in 9.7% of the CAD patients versus 22.6% of the CAD-free subjects (p=0.005). By means of a multiple logistic regression analysis, the AA genotype of the -374T/A polymorphism was shown to be independently associated with a reduced risk of CAD (adjusted odds ratio 0.33, 95% CI 0.15 to 0.73; p=0.006). Our observations suggest that the -374T/A polymorphism of the RAGE gene may reduce susceptibility to CAD, thus exerting a protective effect on coronary risk. Future pathophysiological studies may be worthwhile to clarify the mechanisms behind this association.

The receptor for advanced glycation end product (RAGE) is thought to play an important role in inflammation. Chronic Fatigue Syndrome (CFS) is a long-lasting fatigue that compromises at least 50% of a subject's daily activities without other known cause. Immune dysfunction has been implicated and an association with a peculiar genetic cytokine profile, predisposing to an immunomodulatory response of inflammatory nature, was found. The aim of this study is to analyse RAGE polymorphisms and HLA-DRB1 alleles in seventy-five Italian CFS patients and 141 controls matched for age, sex and ethnicity. These two groups underwent genomic study for RAGE –374T/A and –429C/T promoter polymorphisms; moreover, 46 patients and 186 controls were typed for HLA-DRB1 at low resolution molecular level. Of these, 31 patients and 99 controls also underwent “high resolution analysis” to define the HLA-DRB1*11 and DRB1*13 alleles. The haplotypes RAGE-374T, DRB1*04; RAGE-374T, DRB1*09; RAGE-374T, DRB1*11; RAGE-374A, DRB1*13; RAGE-429T, DRB1*04 and RAGE-429C, DRB1*11 were significantly more frequent in CFS patients, whereas RAGE-429C, DRB1*07 would seem protective. A significantly lower frequency of DRB1*1104 (5.4% vs 12.9% p=0.04, OR=0.39) and a significantly higher frequency of HLA-DRB1*1301 (13.0% vs 5.1% p=0.006, OR= 2.79) were found in CFS patients. A synergic effect was observed with RAGE polymorphism. The OR values strengthened in the following cis combinations: RAGE-374A, HLA-DRB1*1104 (OR=0.27) and RAGE-374A, HLA-DRB1*1301 (OR=6.23). HLA haplotypes rather than single alleles of RAGE or of DRB1 genes seem to be involved in CFS, probably including a subregion of major interest.

Inflammation plays an important role in the pathogenesis of atherosclerosis and coronary syndromes; moreover, various lines of evidence suggest that genetic factors contribute significantly to the risk of coronary artery disease (CAD). Through its effects on endothelial function, coagulation, insulin resistance and lipid metabolism, the proinflammatory cytokine TNF could be involved in cardiovascular pathophysiology. The aim of our study is to analyze whether TNF gene promoter (-308 G/A; −857 G/A) and TNF receptor polymorphisms (TNFR1 MspA1 I exon 1 and TNFR2 Nla III exon 6) show involvement in CAD predisposition in a group of Italian patients compared with healthy controls. Genotyping was performed by PCR-RFLP. Consecutive Italian patients with angiographically proven CAD (n= 248) were compared with controls (n=241), matched for age, sex and geographical origins. CAD patients showed a higher frequency of the TNF −308 A allele than healthy controls (p=0.046). After stratification according to risk factors for CAD, our analysis revealed that CAD patients with diabetes (p=0.042) and CAD patients without hypertension (p=0.0495) displayed a higher frequency of the TNF −308 AA genotype compared with healthy controls. Our data stress the inflammatory nature of CAD and show a possible involvement of TNF −308G/A promoter polymorphisms in the predisposition to the development of this disease. The less frequent A allele seems to be a predisposing factor for development of CAD in particular pathological settings associated with the disease itself, such as diabetes.