Intercellular adhesion molecule 1 gene associations with immunologic subsets of inflammatory bowel disease

Functional variants in intercellular adhesion molecule-1 and toll-like receptor-4 genes are more frequent in children with febrile urinary tract infection with renal parenchymal involvement

AIM

We studied the functional polymorphisms of intercellular adhesion molecule-1 (ICAM-1) and toll-like receptor-4 (TLR-4) genes and risk of acute pyelonephritis (APN) in children attending Assiut University Children's Hospitals, Egypt, from 2011 to 2015.

METHODS

Urinary tract infections (UTIs) were diagnosed in 380 children: 98 had APN and 282 had lower UTIs. Four single-nucleotide polymorphisms in ICAM-1 and TLR-4 genes were genotyped in all subjects: ICAM-1 rs1799969 Gly241Arg, ICAM-1 rs5498 Glu469Lys, TLR-4 rs4896791 Thr399Ile and TLR-4 rs4896790 Asp299Gly.

RESULTS

Patients with APN were significantly more likely to have AA genotype of the ICAM-1 rs5498 (1462 A/G) polymorphism (p = 0.04) than children with lower UTIs and the TLR-4 Asp299Gly GG genotype (p = 0.002) and G allele (p = 0.006) than healthy controls. The association with the ICAM-1 Glu469Lys (1462A/G) was less evident. The GG genotype was associated with a modest relative risk of 1.4 (p = 0.1) of developing APN, but was not an independent odds ratio, at 1.2 (p = 0.48).

CONCLUSION

Functional variants in ICAM-1 and TLR-4 genes were increasingly common in children with febrile UTIs with renal parenchymal involvement, but the ICAM-1 Glu469Lys (1462A/G) association was less evident. TLR4 Asp299Gly might independently increase renal parenchymal infection rather than renal scarring.

Intercellular adhesion molecule-1 polymorphisms in patients with Behçet disease: a meta-analysis

OBJECTIVES

To examine the association between the Intercellular adhesion molecule-1 (ICAM1) Polymorphisms and Behçet's disease.

METHODS

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials for original studies up to July 31, 2012 were searched for relevant studies. All pooled odds ratios (ORs) were derived from either fixed or random-effects model with its 95% confidence intervals (CI).

RESULTS

Five studies met the inclusion criteria. Overall, ICAM1 E469 (OR = 1.45, 95% CI = 1.06-1.97), genotype ICAM1 469 E/E (OR = 1.45, 95% CI = 1.09-1.94), ICAM1 241 G/R (OR = 3.65, 95% CI = 1.69-7.89), had significant associations with Behçet's disease. A significant association was found between the presence of skin lesions and genotype ICAM1 469 E/E (OR = 3.52, 95% CI = 1.62-7.66).

CONCLUSIONS

Behçet's disease was associated with the ICAM1 E469, genotype ICAM1 469 E/E, ICAM1 241 G/R polymorphisms in different ethnic groups. Among patients, genotype ICAM1 469 E/E had a significant association with skin lesion.

Intercellular adhesion molecule-1 gene polymorphisms in patients with familial mediterranean fever

Familial Mediterranean fever (FMF) is a disease of unknown etiology characterized by recurrent attacks of polyserositis and fever. Intercellular adhesion molecule-1 (ICAM-1) is known to contribute inflammatory conditions by regulating leukocyte localization at inflammatory sites. The aim of this study was to evaluate the probable association of ICAM-1 G/R 241 and ICAM-1 E/K 469 polymorphisms according to susceptibility with FMF. Sixty-seven FMF patients and 83 healthy volunteers were included in the study. Genomic DNA was extracted from EDTA-preserved whole blood of whole series of patients and controls, and genotyped by polymerase chain reaction (PCR) and allele-specific oligonucleotide techniques for ICAM-1 polymorphisms G/R at codon 241 and E/K at codon 469. The ICAM-1 241 genotype and allele frequencies of FMF patients and healthy volunteers were similar. The frequency of ICAM-1 K469 homozygosity was significantly lower in FMF patients than in the controls (32.8% vs 50.7% subsequently, p=0.03). Moreover, ICAM-1 E469 allele was more frequent in FMF patients than in controls (44.8% vs 32.3%, p:0.03). Our results showed that ICAM-1 469 gene polymorphism could contribute to the pathogenesis of FMF.

Polymorphisms of the ICAM-1 exon 6 (E469K) are associated with differentiation of colorectal cancer

Background

Genetic factors are thought to play a role in development for colorectal carcinogenesis. ICAM-1 is a polymorphic gene, thus, the present study investigated the relationship between the polymorphisms of ICAM-1 and the susceptibility and phenotypical characteristics of colorectal cancer (CRC).

Methods

The polymorphisms at ICAM-1 exon 4 (G241R) and exon 6 (E469K) were detected by PCR with sequence-specific primers. The relationship between specific genotypes of ICAM-1 and differentiation of CRC was evaluated by the histological grade.

Results

We showed only GG genotype of ICAM-1 individuals in either CRC or normal controls. The KK genotype of ICAM-1 K469E was found more frequently than in the controls (P < 0.05). Patients with well-differentiated CRC displayed the KK more frequently than those of poor differentiation (P < 0.05).

Conclusion

The findings indicate that polymorphisms of G241R are rare in Chinese population and that KK genotype of ICAM-1 K469E is significantly associated with well differentiation of CRC.

Role of non-HLA genetic variants in end-stage renal disease

Cytokines and intercellular adhesion molecule (ICAM) play a crucial role in the pathogenesis of primary kidney disease and progression to end-stage renal disease (ESRD). Cytokine secretion is reported to be dependent on the single nucleotide polymorphisms located in the cytokine genes. The role of different polymorphisms in cytokines and ICAM genes as probable susceptibility factors for ESRD has been explored in the present study. The study was conducted on 258 ESRD patients and on ethnically matched 569 controls. Individuals were genotyped for interleukin (IL)-6 (G174C), IL-4 (C590T), tumor necrosis factor-alpha (TNF-alpha) (-G308A and -G238A) and ICAM-1 (A469G) gene polymorphisms using standard polymerase chain reaction-restriction fragment length polymorphism-based method. We observed significant difference in the genotype frequencies of the TNF-alpha-308AA [P = 0.001; odds ratios (OR) = 7.61, 95% confidence intervals (CI) = 2.1-27.9] and TNF-alpha-238AA (P = 0.001; OR = 5.8, 95% CI = 2.2-15.1). Furthermore, C allele of IL-6 -G174C and G allele of ICAM-1 A469G were significantly different in ESRD patients when compared with controls (P = 0.0001; OR = 5.5, 95% CI = 3.9-7.7 and P < 0.0001; OR = 3.8, 95% CI = 3.1-4.7). For the IL-4 C590T polymorphism, although the homozygous mutant genotype (TT) was not found to be significantly associated with ESRD, a statistically significant association with T allele (P = 0.008) was observed. Furthermore, combined analysis showed a higher risk in ESRD patients with high IL-4- and low IL-6-producing genotypes, low IL-4- and low IL-6-producing genotypes and high-producing genotype of TNF-alpha (308 and 238) with the increased risk of 6.47-, 3.7- and 3.3-fold, respectively. Our results suggest that IL-6, IL-4, TNF-alpha and ICAM gene polymorphisms are implicated in ESRD.

Variations in host genes encoding adhesion molecules and susceptibility to falciparum malaria in India

Background

Host adhesion molecules play a significant role in the pathogenesis of Plasmodium falciparum malaria and changes in their structure or levels in individuals can influence the outcome of infection. The aim of this study was to investigate the association of SNPs of three adhesion molecule genes, ICAM1, PECAM1 and CD36, with severity of falciparum malaria in a malaria-endemic and a non-endemic region of India.

Methods

The frequency distribution of seven selected SNPs of ICAM1, PECAM1 and CD36 was determined in 552 individuals drawn from 24 populations across India. SNP-disease association was analysed in a case-control study format. Genotyping of the population panel was performed by Sequenom mass spectroscopy and patient/control samples were genotyped by SNaPshot method. Haplotypes and linkage disequilibrium (LD) plots were generated using PHASE and Haploview, respectively. Odds-ratio (OR) for risk assessment was estimated using EpiInfo™ version 3.4.

Results

Association of the ICAM1 rs5498 (exon 6) G allele and the CD36 exon 1a A allele with increased risk of severe malaria was observed (severe versus control, OR = 1.91 and 2.66, P = 0.02 and 0.0012, respectively). The CD36 rs1334512 (-53) T allele as well as the TT genotype associated with protection from severe disease (severe versus control, TT versus GG, OR = 0.37, P = 0.004). Interestingly, a SNP of the PECAM1 gene (rs668, exon 3, C/G) with low minor allele frequency in populations of the endemic region compared to the non-endemic region exhibited differential association with disease in these regions; the G allele was a risk factor for malaria in the endemic region, but exhibited significant association with protection from disease in the non-endemic region.

Conclusion

The data highlights the significance of variations in the ICAM1, PECAM1 and CD36 genes in the manifestation of falciparum malaria in India. The PECAM1 exon 3 SNP exhibits altered association with disease in the endemic and non-endemic region.

Intercellular adhesion molecule-1 K469E polymorphism in Korean patients with spontaneous preterm delivery

OBJECTIVES

To investigate the association between intercellular adhesion molecule-1 (ICAM-1) gene K469E polymorphism and spontaneous preterm delivery in a Korean population.

METHODS

Genomic DNA was extracted from whole blood from 55 women experiencing preterm labor and 153 multiparous women (control group) with a history of at least 2 term deliveries. DNA samples were analyzed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

The spontaneous preterm delivery (SPD) group carried the 469E allele significantly more frequently than those in the control group (odds ratio [OR], 1.62; 95% CI, 1.04-2.53). The EE genotype was significantly associated with increased risk of SPD (OR, 2.84; 95% CI, 1.17-6.89; P = 0.02). Allelic frequencies in women with abnormal C-reactive protein levels (K = 0.48; E = 0.52) were significantly different from frequencies in the controls (K = 0.68; E = 0.32) (P = 0.006).

CONCLUSIONS

ICAM-1 gene K469E polymorphism may be a candidate region and useful predictor of susceptibility to SPD in the Korean population.

Susceptibility to active decompensated cirrhosis is associated with polymorphisms of intercellular adhesion molecule-1 (ICAM-1) in chronic HBV carriers

Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the pathogenesis of viral hepatitis B. Several inflammatory diseases are associated with distinct polymorphisms of the ICAM-1 gene. The aims of this study were to analyse the association of ICAM-1 polymorphisms G241R and K469E with susceptibility to active decompensated cirrhosis in chronic hepatitis B virus (HBV) carriers. The polymorphisms at codons G241R and K469E of ICAM-1 were analysed by sequence-specific primer polymerase chain reaction (PCR-SSP) in 572 unrelated chronic HBV carriers and 157 unrelated healthy HBV non-infected blood donors. There were significantly increased frequencies of R at codon 241 and E at codon 469 in patients with active decompensated cirrhosis (38.3% and 58.3%), compared with patients with chronic hepatitis B (CHB; 21.9% and 46.5%) and chronic asymptomatic HBV carriers (AsC; 12.6% and 40.3%). The frequencies of R241-E469 haplotype and genotypes carrying at least one R241-E469 haplotype were significantly higher in patients with active decompensated cirrhosis than those in patients with CHB (38.3% and 63.3%vs 21.9% and 36.7%), and significantly higher in patients with CHB than those in AsC (21.9% and 36.7%vs 12.6% and 23.3%). The ICAM-1 polymorphisms at codons G241R and E469K were associated with the disease susceptibility, and susceptibility to active decompensated cirrhosis is significantly increased in chronic HBV carriers carrying at least one R241-E469 haplotype.

TNFSF15 is an ethnic-specific IBD gene

BACKGROUND

Inflammatory bowel disease (IBD) is a clinically and, likely, genetically heterogeneous group of disorders. A recent report suggests that genetic variations in the TNFSF15 gene contribute to the susceptibility of IBD in both Japanese and Caucasian populations. The aim was to confirm the association between TNFSF15 high- and low-risk haplotypes and IBD in a Caucasian population.

METHODS

Five single-nucleotide polymorphisms (SNPs) that comprise the 2 common haplotypes were genotyped in 599 Caucasian patients with Crohn's disease (CD), 382 Caucasian patients with ulcerative colitis (UC), and 230 ethnically matched healthy controls, including both Jews and non-Jews.

RESULTS

The previously reported 'risk' haplotype was not associated with CD or UC (88.2% in CD cases versus 88.3% in controls, P = 0.96; 88.1% in UC cases versus 88.3% in controls, P = 0.78). We did, however, observe an increased frequency of the "protective" haplotype in non-Jewish controls for both CD and UC (38.8% CD cases versus 50% controls, P = 0.01; 37.3% UC cases versus 50% controls, P = 0.01) with no such effect observed in the Jewish samples. There was an interactive effect between ethnicity and the protective haplotype in CD (P = 0.04).

CONCLUSIONS

We observed a protective haplotype, consisting of the minor alleles for all 5 markers, to have a higher frequency in the non-Jewish controls than in CD and UC. Of further interest, the haplotype frequency was in the opposite direction in our Jewish case-control panels (both CD and UC), leading us to conclude 1) that TNFSF15 is indeed an IBD susceptibility gene, and 2) the disease susceptibility is ethnic-specific.

Polymorphisms in NFKBIA and ICAM-1 genes in New Zealand Caucasian Crohn's disease patients

BACKGROUND AND AIM

Crohn's disease (CD) is a complex polygenetic inflammatory disease of the bowel. NFKBIA (IkappaBalpha) is a downstream regulator of NF-kappaB, which is an effector of the major Crohn's susceptibility gene CARD15/NOD2. ICAM-1 is an integrin ligand and vascular addressin, which contributes to the trafficking of pathogenic leukocytes into the inflamed bowel. Here we examined whether the NFKBIA 2758G/A and ICAM-1 K469E variants, recently shown to be CD susceptibility genes in Caucasian populations in Germany and the United Kingdom, are associated with CD in Caucasian patients in New Zealand.

METHODS

PCR-RFLP analysis was used to examine the frequency of gene polymorphisms in 182 CD patients and 188 ethnically matched controls.

RESULTS

There was no significant evidence of a difference in the allele frequency of either the 2758G/A polymorphism in NFKBIA (0.38 vs 0.35, P = 0.47) or the K469E polymorphism in ICAM-1 (0.43 vs 0.37, P = 0.10) between CD patients and controls. Nevertheless, the ICAM-1 469E allele significantly (P = 0.016, Pc = 0.047) influenced the age of diagnosis of CD. Meta-analysis with five other studies confirmed a lack of association of the K469E polymorphism with Crohn's disease (P = 0.33; OR = 0.93; 95% CI, 0.82-1.07).

CONCLUSION

The NFKBIA 2758G/A and ICAM-1 K469E polymorphisms are not significant risk factors for CD in New Zealand; however, there is evidence that the latter polymorphism influences the age of diagnosis.

The association of ICAM-1 Exon 6 (E469K) but not of ICAM-1 Exon 4 (G241R) and PECAM-1 Exon 3 (L125V) polymorphisms with the development of differentiation syndrome in acute promyelocytic leukemia

The use of all trans-retinoic acid (ATRA) is the basis of treatment of acute promyelocytic leukemia (APL) and represents the paradigm of differentiation therapy. In general, ATRA is well-tolerated but may be associated with a potentially lethal side-effect, referred to as retinoic acid or differentiation syndrome (DS). The cellular and molecular mechanisms of DS are poorly understood and involve changes in the adhesive qualities and cytokine secretion of leukemic cells during ATRA-induced differentiation. As leukocyte extravasation is a key event in DS pathogenesis, we analyzed the association between the polymorphisms at Exon 4 (G241R) and Exon 6 (E469K) of ICAM-1 and Exon 3 (L125V) of PECAM-1 genes with DS development in APL patients treated with ATRA and anthracyclines. DS was diagnosed in 23/127 (18.1%) APL patients at an average of 11.5 days after the start of ATRA. All patients presented respiratory distress associated with increased ground-glass opacity in chest radiographies. Other accompanying symptoms were: fever not attributable to infection (65.2%), generalized edema (37.5%), weight gain (37.5%), and impairment of renal function (8.6%). We detected an association between development of DS and the AA genotype at Codon 469 of ICAM-1 (odds ratio of 3.5; 95% confidence interval: 1.2-10.2). Conversely, no significant association was detected between G241R or L125V polymorphisms at Exon 4 of ICAM-1 and Exon 3 of PECAM-1, respectively. Our results suggest that susceptibility to DS in APL patients may be influenced by genetic variation in adhesion molecule loci.

Rapid detection of intercellular adhesion molecule 1 (G241R and K469E) polymorphisms by a novel PCR-SSP assay

Intercellular adhesion molecule 1 (ICAM-1) is a cell surface glycoprotein member of the immunoglobulin superfamily and is actively involved in immune and inflammatory responses. We introduce a novel polymerase chain reaction-sequence-specific primers (PCR-SSP) method for rapid and simultaneous genotyping of ICAM-1 G241R and K469E polymorphisms. In a total of 184 DNA samples that have been previously analyzed for these polymorphisms using polymerase chain reaction-restriction fragment length polymorphism technique, re-genotyping of all samples with this new assay showed accurate and reproducible results. As PCR-SSP-based genotyping protocols are more convenient and cost-effective to do, it could therefore offer a valuable tool for assessment of ICAM-1 polymorphisms to which more confirmatory studies are needed.

Intercellular adhesion molecule 1 gene polymorphisms do not contribute to Graves' disease in Chinese patients

OBJECTIVE

In order to study the association of G241R polymorphism of ICAM-1 gene with an earlier onset of Graves' disease (GD) and the susceptibility of K469E polymorphism to Graves' ophthalmopathy (GO) in Chinese population.

STUDY DESIGN

A case-control and replication study was performed in 212 GD patients and 204 healthy subjects to analyze the genotypes. Furthermore the distribution of ICAM-1 genotypes was investigated in subgroups of patients with GD according to the onset age and the ophthalmopathy.

RESULTS

No G241R polymorphism of ICAM-1 gene was detected in Chinese. No significant differences of allele and genotype frequencies regarding K469E polymorphism were found between GD patients and healthy controls (chi2 = 0.092, P = 0.762; chi2 = 1.089, P = 0.580). In addition, the genotype-phenotype correlation was not identified either.

CONCLUSIONS

We found no association of G241R and K469E polymorphisms of the ICAM-1gene with the development of GD in a Chinese population. However, we could not rule out possible contributions of other polymorphisms of the ICAM-1gene to the pathogenesis of GD. Therefore, further studies are needed to elucidate the role of ICAM-1gene in Graves' disease in different population.

Analysis of MAdCAM-1 and ICAM-1 polymorphisms in 365 Scandinavian patients with primary sclerosing cholangitis

BACKGROUND/AIMS

Mucosal addressin cellular adhesion molecule-1 (MAdCAM-1) has been implicated in the aberrant homing of intestinal lymphocytes to the liver in primary sclerosing cholangitis (PSC). Intercellular adhesion molecule-1 (ICAM-1) has also been implicated in the pathogenesis of PSC and the E/E genotype of the K469E polymorphism has been reported to be associated with PSC susceptibility. The aims of this study were to determine if MAdCAM-1 polymorphisms or the K469E polymorphism of ICAM-1 are associated with PSC in Scandinavia.

METHODS

Seven single nucleotide polymorphisms (SNPs) in MAdCAM-1 and the G421R and K469E ICAM-1 SNPs were genotyped in 365 PSC patients from Norway and Sweden. 327 Norwegian ulcerative colitis (UC) patients and 368 Norwegian bone marrow donors served as controls.

RESULTS

No significant association with PSC was found for any of the MAdCAM-1 or ICAM-1 SNPs. Allele frequencies for these polymorphisms were not significantly different between PSC patients with UC, UC patients and healthy controls.

CONCLUSIONS

Polymorphisms in MAdCAM-1 are not likely to significantly affect PSC susceptibility. In addition, the E/E genotype of the K469E in ICAM-1 does not influence PSC susceptibility in Scandinavia.

Relation between common polymorphisms in genes related to inflammatory response and colorectal cancer

AIM: To investigate the association between common single nucleotide polymorphisms (SNPs) in inflammatory response-related genes such as interleukin (IL)-6, IL-8, tumor necrosis factor α (TNFα), peroxisome proliferators-activated receptor γ (PPARγ), intercellular adhesion molecule-1 (ICAM-1) and the risk of colorectal cancer (CRC) in a group of Greek patients.

METHODS: The study group consisted of 222 CRC patients and 200 healthy controls. Genotyping was performed using allele-specific PCR of PRC-RFLP and the results were confirmed by sequencing. We studied the association of SNPs in the IL-6 (-174G > C), IL-8 (-251T > A), TNFα (-308G > A), ICAM-1 (R241G and K469E), and PPARγ (Pro12Ala) genes and the risk of CRC.

RESULTS: The IL-6 -174G, R241 and K469 alleles of ICAM-1 were associated with increased risk of CRC (OR = 1.77, 95% CI: 1.34-2.34; OR = 1.83, 95% CI: 1.23-2.72; and OR = 1.35, 95% CI: 1.03-1.77 respectively). The IL-8 and TNFα polymorphisms had no effect. Whereas the PPARγ Pro12 genotype was associated with increased risk of disease (OR = 1.78, 95% CI: 1.25-2.49).

CONCLUSION: The association between common SNPs in immunologic response-related genes and CRC is reported in the present study. Apart from shedding light on the mechanisms of malignancy initiation and progression, SNPs may improve appropriate screening for sub-populations at risk.

Genetic variants and the risk of Crohn's disease: what does it mean for future disease management?

Genetic research in inflammatory bowel disease, especially in Crohn's disease, has made significant progress during recent years. There have been > 10 total genome scans that have been performed, and susceptibility loci on several chromosomes have been identified. Together with candidate gene studies, these scans have led to the identification of several susceptibility genes, with CARD15 being the most important. These genetic data have already provided important insights into the pathophysiology of inflammatory bowel disease and are stimulating future research. On the other hand, genotype-phenotype associations have illustrated the heterogenic nature of the disease. Although the clinical application of this knowledge is so far limited, there is significant optimism that an individual management of patients based on genetic data will be possible in the near future.

Haplotype-based association analysis of 56 functional candidate genes in the IBD6 locus on chromosome 19

Evidence from four independent linkage studies and two meta-analyses of genome-wide data support the existence of a locus conferring susceptibility to inflammatory bowel diseases (IBD) in chromosomal region 19p. Identification of a susceptibility allele in this approximately 28.5 Mb region with over 600 genes is a formidable task. To tackle this problem, we undertook two approaches: (1) haplotype-based candidate-gene screen, and (2) evaluation of previously reported associations. For the former, we selected genes with potential implication in IBD pathogenesis based on published functional and expression data, typed SNPs, constructed haplotypes, screened for association in 180 IBD trios, and followed up preliminary associations in 343 IBD patients and 207 control individuals. Overall, we analyzed 465 SNPs, and 260 haplotypes distributed across 56 candidate genes. We found suggestive evidence of association (nominal P<0.01) with four genes (C3, FCER2, IL12RB1, and CRLF1) in a screening stage, but were unable to confirm these preliminary observations at follow-up. In the second approach, we typed four nonsynonymous polymorphisms in genes C3 (R102G and L314P) and ICAM1 (G241R and K469E) in four independent cohorts totaling 2178 IBD cases. We evaluated these data together with previously published reports for three of these variants (C3-Gly102, ICAM1-Arg241, and ICAM1-Glu469), in a meta-analysis. Our pooled meta-analysis provides compelling evidence against association of these variants with disease. Overall, we performed the most comprehensive candidate-gene association study for IBD to date. The information hereby generated constitutes a valuable resource to investigate other common genetic immune diseases, such as celiac disease.

Immunopathogenesis of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown etiology;however, lymphocytic portal tract infiltration is suggestive of an immune-mediated basis for PSC. Associations with inflammatory bowel disease--especially ulcerative colitis--and with other auto-immune diseases, together with genetic associations, further suggest that PSC may be an immune-mediated disease. The immunogenetics of PSC have been the subject of active research, and several human leukocyte antigen (HLA)- and non-HLA-associated genes have been implicated in the development of the disease. Lymphocytes derived from the inflamed gut may enter the liver via the enterohepatic circulation to cause hepatic disease.PSC may be triggered in genetically susceptible individuals by infections or toxins entering the portal circulation through a permeable colon and, therefore, evoking an abnormal immune response.

NOD2/CARD15, NOD1/CARD4, and ICAM-1 gene polymorphisms in Turkish patients with inflammatory bowel disease

PURPOSE

The genetic susceptibility of people with certain NOD2/CARD15, NOD1/CARD4, and ICAM-1 gene variants to inflammatory bowel disease is still under investigation. The aim of this study was to investigate polymorphisms in the NOD2/CARD15 (R702W, G908R, and 3020insC), NOD1/CARD4 (E266K, D372N), and ICAM-1 (G241R, K469E) genes, which are known to be associated with inflammation, in Turkish patients with inflammatory bowel disease and healthy control groups.

METHODS

The genotypes of 70 patients with endoscopically and histopathologically diagnosed Crohn's disease (38 men, 32 women; mean age, 38.8 +/- 1.3), 120 patients with ulcerative colitis (67 men, 53 women; mean age, 41.7 +/- 1.3) and 106 healthy control subjects (37 men, 69 women; mean age, 35.7 +/- 1.4), who stated that they had never had any prior bowel disease history, were compared. A polymerase chain reaction-restriction fragment length polymorphism analysis was performed for two variants of the ICAM-1 gene, the three main variants of the NOD2/CARD15 gene, and the E266K variant of the NOD1/CARD4 gene, and DNA sequencing was used for the D372N polymorphism of the NOD1/CARD4 gene.

RESULTS

In this study, the three previously described Crohn's disease-predisposing variants of the NOD2/CARD15 gene and the polymorphisms examined in the NOD1/CARD4 and ICAM-1 genes were not found to be associated with ulcerative colitis or Crohn's disease.

CONCLUSIONS

These findings suggest that the polymorphisms observed in the NOD2/CARD15, NOD1/CARD4, and ICAM-1 genes are not genetic susceptibility factors for Crohn's disease or ulcerative colitis in Turkey.

Association between ICAM-1 Gly-Arg polymorphism and renal parenchymal scarring following childhood urinary tract infection

Renal parenchymal scarring (RPS) following urinary tract infection (UTI) is an important cause of renal morbidity in children. Studies have shown that the intensity of the inflammatory response following infection is related to the risk of RPS. However, genetic variability in this response has not been studied. Adhesion molecules play a crucial role in leucocyte recruitment following infection, and polymorphisms have been reported in the genes for key cell adhesion molecules. We have investigated the possibility that children who develop RPS following UTI may exhibit altered genotype or allele frequencies for polymorphisms of the intercellular adhesion molecule-1 (ICAM-1) (exons 4 and 6), E-selectin (exons 2 and 4), platelet endothelial cell adhesion molecule-1 (PECAM-1) (exon 3) and CD11b (3'UTR) genes, which may predict outcome of UTI. DNA was isolated from 99 children shown to have developed RPS, 43 children with no evidence of scarring (NS) following UTI and 170 healthy controls. Genotyping was performed by restriction fragment length polymorphism (RFLP) analysis. When the RPS group was compared with the NS group, there was a significant reduction in the frequency of the ICAM-1 exon 4 A allele (10.6 vs. 21.3%, respectively, chi2 = 6.01, P = 0.014). There was no significant difference in either allele or genotype frequency for any of the other polymorphisms studied. These data suggest that the A allele of the ICAM-1 exon 4 polymorphism may protect against the risk of RPS following UTI and may participate in the regulation of the inflammatory response following UTI.

Association study of endometriosis and intercellular adhesion molecule-1 (ICAM-1) gene polymorphisms in a Japanese population

OBJECTIVE

Endometriosis is an immune-related, chronic inflammatory disease with polygenic predisposition. Cell adhesion molecules are expressed in endometriotic lesions, and in cells and tissues that are involved in the development and progression of the disease. In this study, we investigated the possible association between endometriosis and the G241R and K469E polymorphisms in the intercellular adhesion molecule-1 (ICAM-1) gene in a Japanese population.

METHODS

We compared the distribution of the G241R and K469E polymorphisms in the ICAM-1 gene in 126 endometriosis patients and 172 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in a Japanese population.

RESULTS

There were no significant differences between the cases and controls in the allele frequencies or genotype distributions of either the G241R or K469E polymorphisms in the ICAM-1 gene. The endometriosis patients were divided into a subgroup of women with severe disease only. However, no significant differences were observed in the allele frequencies and genotype distributions of the ICAM-1 K469E polymorphisms between this subgroup and the controls. In contrast, only one in 169 controls was heterozygous (G/A genotype), and the A allele in the G241R polymorphism was not found in any of the 126 endometriosis patients.

CONCLUSION

Our findings suggest that the G241R and K469E polymorphisms in the ICAM-1 gene are unlikely to be associated with an increased risk of endometriosis in the Japanese population.

Plasmodium falciparum malaria in south-west Nigerian children: is the polymorphism of ICAM-1 and E-selectin genes contributing to the clinical severity of malaria?

Plasmodium falciparum malaria remains a major public health hazard in sub-Saharan African children. While the factors that determine the variations in clinical outcome of a malaria have not been completely defined, both host and parasite factors, as well as the complex molecular interactions between them have been implicated. The cyto-adherent properties of the P. falciparum-infected red blood cells are considered as key properties in the pathogenesis of malaria and the polymorphisms of the host adhesion molecules could contribute to the severity of malaria. Clinical information and blood samples were collected from 223 children from Ibadan (south-west Nigeria), median age of 34.5 months, presenting with different clinical manifestations of malaria--clinically asymptomatic parasitism (ACP), acute uncomplicated malaria (UM) and severe malaria (SM)--as defined by WHO criteria. The polymorphisms of genes coding for four human adhesion molecules at six different loci (ICAM-1 exons 2, 4 and 6, E-selectin exon 2, CD36 exon 10, and PECAM exon 3) were studied. DNA samples were prepared for further genotyping of the six exons mentioned above by PCR-RFLPs using the appropriate restriction digests for each loci. The ICAM-1 exon 4 locus was monomorphic. All the other loci were at Hardy-Weinberg equilibrium (HWE). The E-selectin locus had very low heterozygosity (approximately 0.06) in contrast to the other loci under study (0.23-0.44). Once the data was further processed for covariates (age and parasite density) and taking as the reference category the ACP group, results show that in the presence of the G allele at the ICAM-1 exon 6 there is an increased risk (3.6 times) of severe malaria. As far as the T allele in the E-selectin exon is concerned, the number of sampled DNAs with the T allele within both the UM and SM categories is too low for drawing any relevant conclusion at this stage. In conclusion, these results suggest that genetic polymorphisms at host adhesion molecules loci are an important variable in the susceptibility to severe malaria. Further studies of host loci are needed to further delineate which polymorphisms are associated with severe malaria and increase our knowledge of the biology of host-parasite interactions.

Gene polymorphisms and serological markers of patients with active Crohn's disease in a clinical trial of antisense to ICAM-1

Serological profiles for anti-Saccharomyces cerevisiae antibodies (ASCA)/ perinuclear antineutrophil cytoplasmic antibodies (pANCA) and gene polymorphisms in tumour necrosis factor (TNF)-alpha and intercellular adhesion molecule-1 (ICAM-1) are associated with occurrence and/or outcome in Crohn's disease. The aim of the study was to characterize the ASCA/pANCA profile, soluble ICAM-1 expression and single nucleotide gene polymorphisms (SNPs) in TNF-alpha and ICAM-1 genes. Crohn's patients with moderate disease activity were enrolled in a clinical trial of Alicaforsen (ISIS 2302). Peripheral blood samples were collected prospectively for serum studies and for potential analysis of gene polymorphisms. A multivariate analysis was performed to compare treatment effect with the biomarkers studied. Serological testing for ASCA/pANCA was obtained for 257 patients at baseline: 37% were ASCA(+)/pANCA(-) (Crohn's pattern), 9% had both markers, 15% were ASCA(-)/pANCA(+) and 39% had neither marker. When the data were analysed by multiple regression analysis, a trend was found within the Alicaforsen-treated groups for greater rates of remission in the ASCA(+)/pANCA(-) subgroup versus all other serological profiles (25 versus 14%, P = 0.068), but not versus the placebo remission rate (18.8%). Gene polymorphisms were assessed in 64 patients, 21 from the placebo group. ICAM-1 assessment revealed no over-representation. However, three unique TNF-alpha SNPs were identified that correlated significantly with remission; sites 290 (P = 0.0253), -2735 (P = 0.0317) and -3090 (P = 0.0067). Although the overall clinical trial was negative, we have identified a trend towards clinical remission with Alicaforsen therapy in a subgroup of patients with Crohn's disease expressing ASCA(+)/pANCA(-). Furthermore, we have identified three TNF-alpha SNPs that may also predict a positive therapeutic outcome.

Intercellular adhesion molecule-1 and childhood asthma

We investigated the role of intercellular adhesion molecule-1 in childhood asthma by examining associations of functional variants at codons 29 (A --> T), 241 (G --> A), and 469 (A --> G) in Children's Health Study participants. Among African-Americans, 469G carriers had lower risk for asthma (ever asthma OR = 0.4, 95% CI 0.2-0.9) but increased risk among 29T carriers (early onset active asthma OR = 2.2, 95% CI 1.0-4.9). Protective associations with the 241A allele were observed among non-Hispanic and Hispanic whites (ever asthma OR = 0.7, 95% CI 0.6-0.9; early onset active asthma OR = 0.5, 95% CI 0.4-0.8), and these associations were not confounded by population stratification. To gauge the potential impact of confounding by population stratification, we performed analyses by ethnic group and in an independent family-based sample. Regional associations were stable across analyses. Haplotype associations of the four common haplotypes (29A/241G/469A, AGG, TGA, and AAG) with asthma showed that Hispanics with the AAG haplotype had lower asthma risk compared to carriers of two copies of AGA haplotype (OR = 0.6, 95% CI 0.4-0.9). Among non-Hispanic whites, the AAG haplotype was associated with reduced risk for active asthma. For African-Americans, who had a low frequency of the AAG haplotype, carrying one copy of the AGG haplotype was associated with a lower risk of asthma (OR = 0.3, 95% CI 0.1-0.8), as compared with two copies of the AGA haplotype. Consistent with information on variant function, the 241A and 469G variants may indicate haplotypes that are associated with reduced risk for asthma.

Pancreatic autoantibodies in Crohn's disease: a feasible diagnostic tool?

Potential implications of antibody markers in Crohn's disease: Diagnostic markers, alone or in conjunction with other antibodies? Delineation of clinical phenotypes? Markers of disease behaviour? Markers of (genetic) susceptibility? Identification of genetically homogenous subgroups? Bridge between basic science and clinic? The exact role of serum antibodies in inflammatory bowel disease remains a matter of ongoing debate. Although a direct implication in the disease pathogenesis is unlikely, their diagnostic potential in cases of an undetermined colitis or in defining clinical phenotypes in Crohn's disease has been shown in several studies. Serum antibodies might also be helpful in predicting the disease behaviour and are thus valuable tools in the choice of medical or surgical therapy.

ICAM G241A polymorphism and soluble ICAM-1 serum levels: evidence for an active immune process in schizophrenia

OBJECTIVES

We have previously reported reduced serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in schizophrenic patients. A single-nucleotide polymorphism (SNP) of the ICAM-1 gene was described at position 241. The G-->A SNP results in a nonsynonymous amino acid exchange of the ICAM-1 protein, and the A allele was shown to be also associated with several immunological disorders like rheumatoid arthritis.

METHODS

We investigated 70 schizophrenic patients and 128 unrelated healthy control persons regarding the relationship between the serum levels of sICAM-1 and the ICAM-1 G214A polymorphism.

RESULTS

We were able to replicate our previous finding of reduced sICAM-1 levels in schizophrenia. Healthy control persons carrying the polymorphic A allele showed markedly lower sICAM-1 serum levels than carriers of the homozygous GG wild type (p < 0.004). In contrast, no significant difference in the sICAM-1 serum levels were seen regarding the G241A genotype distribution in schizophrenic patients.

CONCLUSION

We hypothesize that the biochemical effect of the G241A SNP is masked in schizophrenic patients, indicating a disease-related mechanism leading to reduced levels of sICAM-1 in schizophrenia.

Intercellular adhesion molecule-1 polymorphisms in Korean patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is characterized by synovial proliferation and the accumulation of inflammatory cells in the affected joints. Intercellular adhesion molecule-1 (ICAM-1) is readily detected in RA synovial tissues and helps recruit inflammatory cells to the joint. ICAM-1 shows genetic polymorphisms at codons 241 (R241G) and 469 (K469E). In order to investigate the association between ICAM-1 gene polymorphisms and RA, we genotyped ICAM-1 R241G and ICAM-1 K469E polymorphisms in 143 Korean patients with RA, and in 138 healthy controls, by using the polymerase chain reaction-restriction fragment length polymorphism method. No polymorphism of R241G was found in Korean subjects. However, the frequency of the K469 allele was found to be significantly lower in RA patients than in healthy controls. Allele frequency of K469 was lower in RA patient group, compared to that in healthy controls, regardless of the shared epitope status. Distribution of K469E allele frequencies was not different whether the patient had rheumatoid factor, radiographic erosion or extra-articular complications. In conclusion, this study shows lower frequency of the ICAM-1 K469E allele in Korean patients with RA than that in healthy controls.

Prevalence of the K469E polymorphism of intercellular adhesion molecule 1 gene in Italian patients with inflammatory bowel disease

BACKGROUND

Intercellular adhesion molecule 1 plays an important role in the recruitment of leucocytes at sites of inflammation and is up-regulated in intestinal mucosa of inflammatory bowel disease. Intercellular adhesion molecule 1 gene lies on chromosome 19p13, implicated in determining susceptibility to inflammatory bowel disease. Recently, the polymorphism K469E of intercellular adhesion molecule 1 gene has been identified.

AIM

To assess the potential association of this polymorphism with inflammatory bowel disease.

PATIENTS

A total of 165 inflammatory bowel disease patients, 75 with Crohn's disease and 90 with ulcerative colitis, and 187 controls were studied.

METHODS

The K469E polymorphism was detected by polymerase chain reaction and restriction enzyme analysis. Statistical analysis was performed by chi2-test.

RESULTS

In inflammatory bowel disease, the distribution of intercellular adhesion molecule 1 genotypes was 24.9% E/E, 44.2% E/K and 30.9% K/K. In controls, 11.8% showed E/E genotype, 55.6% E/K and 32.6% K/K. The frequency of the E/E genotype was significantly higher in inflammatory bowel disease (Crohn's disease and ulcerative colitis) patients than in controls. Subgroup analysis showed that the frequency of the E469 allele was significantly increased only in Crohn's disease patients with ileocolonic location of disease and penetrating behaviour compared with controls.

CONCLUSIONS

We found an association of inflammatory bowel disease with the E/E genotype of intercellular adhesion molecule 1 gene, while allele E469 was associated with a subgroup of Crohn's disease patients with more extensive location of disease and penetrating behaviour. However, further studies are needed to confirm our findings.

Single-nucleotide polymorphism g.1548G > A (E469K) in human ICAM-1 gene affects mRNA splicing pattern and TPA-induced apoptosis

The single-nucleotide polymorphism (SNP) g.1548G > A (E469K) in the human intercellular adhesion molecule-1 (ICAM-1) gene has been suggested to have an association with several types of inflammatory diseases. The polymorphism is located at the three-base position upstream of the splice donor site that produces an alternatively spliced short isoform (ICAM-1-S). To clarify its functional relevance, we studied RNA splicing patterns by comparing cells with different genotype (G/G cells and A/A cells). G/G cells expressed a lower amount of ICAM-1-S mRNA than A/A cells. Since ICAM-1-S has no transmembrane or intracellular domain, ICAM-1 signal transduction and cell-cell contact including Fas-FasL interaction may be influenced. In addition, we studied the effect of this change on FLIP-L mRNA and apoptosis. FLIP-L mRNA tended to decrease, while cell death induced by phorbol 12-myristate 13-acetate was increased. These results suggest that the g.1548 polymorphism modifies inflammatory immune responses by changing cell-cell interaction and then regulating apoptosis.

Inflammatory bowel disease is linked to 19p13 and associated with ICAM-1

Genome-wide scans have implicated several susceptibility loci, but linkage of 19p13 (IBD6) to Crohn's disease (CD) has not been fully replicated. We report a replication study of IBD6 in a UK Caucasian population. Two hundred eighty-four affected sibling pairs from 234 families were used for the linkage study. Linkage between IBD6 linkage and CD was replicated (LOD score = 1.59). Two candidate genes (DDXL and ICAM-1) within the IBD6 locus were examined in a case/control study with a total of 228 CD and 243 ulcerative colitis (UC) patients and 407 healthy controls. No association to either UC or CD was found in three novel intronic single nucleotide polymorphisms (SNPs) in DDXL. For ICAM-1, a significant association was found between K469 homozygosity and CD overall (39.9% vs 29.4%; Pc = 0.0096) and between E469 and fistulating disease (21.8% vs 10.0%, Pc = 0.030). In the UC group, limited disease extent was associated with homozygosity of the G241 allele (82.7% vs 64.7%, Pc = 0.0040). These data support linkage for CD at 19p13 and suggest that the amino acid polymorphisms in ICAM-1 may be associated with IBD.

Susceptibility to primary sclerosing cholangitis is associated with polymorphisms of intercellular adhesion molecule-1

BACKGROUND/AIMS

Intercellular adhesion molecule-1 (ICAM-1, CD54) gene polymorphisms have been implicated in the susceptibility to a range of inflammatory diseases, including inflammatory bowel disease (IBD). Primary sclerosing cholangitis (PSC) is an immune-mediated chronic cholestatic liver disease associated with IBD. ICAM-1 is expressed on proliferating bile ducts and interlobular bile ducts in late stage PSC and serum levels of soluble intercellular adhesion molecules are increased in PSC. The aim of this study was to analyse ICAM-1 gene polymorphisms in PSC patients.

METHODS

In this study, 104 patients with PSC and 213 healthy controls were recruited from Oxfordshire Caucasians. PCR with sequence-specific primers (PCR-SSP) was used to detect both ICAM-1 biallelic polymorphisms G241R and K469E. The results were controlled for the HLA haplotypes associated with PSC.

RESULTS

The E/E frequency of K469E in PSC was 12% (12/104), significantly lower than that in controls (24%, 51/213;P = 0.009; Pc = 0.02; OR, 0.41). The occurrence of the haplotype G241-E469/G241-E469 in PSC was 4% (4/104), significantly lower than the control group (13%, 28/213; P = 0.01; Pc = 0.04; OR, 0.26). There was no difference between PSC and control groups in the frequencies of the genotype R241G or in allele frequencies of K469E.

CONCLUSIONS

The E469E homozygote status for ICAM-1 is associated with protection against PSC.

Behçet's disease: from Hippocrates to the third millennium

Behçet's disease (BD) is characterised by recurrent episodes of orogenital aphthae, systemic vasculitis, and systemic and retinal venous thrombosis. An association between HLA-B51 and BD was first identified over 20 years ago, but recently identified gene associations implicate regions both within and without the MHC in the immunological events underlying the lesions in BD. These include allelic variants within the tumour necrosis factor gene region and within the MHC class I chain related gene region, the factor V Leiden mutation, which is associated with retinal vascular occlusion, and alleles of the intercellular adhesion molecule gene. No single causative gene for BD has emerged; the evidence indicates that the underlying immune events in BD are triggered by a microbial antigen and subsequently driven by genetic influences which control leucocyte behaviour and the coagulation pathways. Knowledge of these risk factors may permit a more accurate prognosis for a given patient, and identify new pathways for more targeted intervention than is currently available.

Association between Gly241Arg ICAM-1 gene polymorphism and serum sICAM-1 concentration in the Stanislas cohort

Intracellular adhesion molecule-1 (ICAM-1), a cellular adhesion molecule that mediates the interaction of activated endothelial cells with leukocytes, is involved in various inflammatory and cardiovascular disorders. The relation between these markers and genetic polymorphism, however, remains to be elucidated. The aim of this study is to estimate the effect of a single-base polymorphism at codon 241 in exon 4 of ICAM-1 gene on serum sICAM-1 concentration in a healthy population, taking into account other biological determinants of sICAM-1 level. Serum sICAM-1 levels and the G/R241 polymorphism of the ICAM-1 gene were measured in a large healthy population consisting of 413 children aged 6-21 years and 363 adults aged 38-55 years extracted from the Stanislas cohort. The R241 allele was significantly associated with lower sICAM-1 levels and explained 3.4 and 1.9% of the sICAM-1 variability in children and adults, respectively. A codominant pattern contributed better to the model after adjustment for covariates as the RR homozygote effect was higher than that of the GR heterozygote. Moreover, significant independent associations were found between sICAM-1 and smoking, insulin resistance index (HOMA IR), interleukin-6 level, and alkaline phosphatase and aspartate aminotransferase activities. In conclusion, this study revealed a significant association between the G/R241 ICAM-1 polymorphism and serum sICAM-1 levels, probably due to the impairment in binding of ICAM-1 to leukocyte integrin Mac-1 protein.

Progress in searching for susceptibility gene for inflammatory bowel disease by positional cloning

Inflammatory bowel disease (IBD) includes two clinical subtypes: Crohn disease (CD) and ulcerative colitis (UC). The general prevalence is about 1.0%-2.0% in Western countries. It is predominantly regarded as a multifactorial disorder involving environmental factors and polygenic defects. The view was confirmed by a lot of evidences from clinical attributions and animal models, especially from epidemiological investigations. So the etiological study of IBD has been focused on searching for susceptibility genes by positional cloning, which consists of two steps: linkage analysis and association analysis. Linkage analysis has been an important method of searching for susceptibility genes to polygenic diseases as well as single-gene disorders. IBD, as a polygenic disease, has been widely investigated by linkage analysis for susceptibility gene since 1996. The paper reviewed 38 articles, which covered almost all original researches in relation to IBD and linkage analysis. So far, several loci, such as 16q, 12q, 6p and 3p, have been identified by the studies. The most striking is 16q12 (IBD1), which linked only with CD not UC in the majority of studies. Association analysis, as one essential step for positional cloning, is usually carried out by genotyping candidate genes selected by means of linkage analysis or other methods, for figuring out the frequencies of alleles and comparing the frequencies between IBD group and healthy control group to identify the specific allele. It has been established that IBD is implicated in immune disorder. So the studies were centered on the genes of NOD2/CARD15, HLA-II, cytokine, cytokine receptor and adhesion molecule. This paper reviewed 14 original articles on association between NOD2 and IBD that have been published since 2001. All results, with the exception of one report from a Japanese group, provide evidences that the three kinds of variants of NOD2 are susceptibility factors for IBD. This article also comprehensively analyzed 18 original researches of HLA gene polymorphism in IBD. We found extensive discrepancy among the conclusions and a novel hypothesis was put forward to explain the discordance. Most studies published recently on association between IBD and cytokine gene polymorphism were reviewed.

Review article: the expanding role of biological agents in the treatment of inflammatory bowel disease - focus on selective adhesion molecule inhibition

Inflammatory bowel disease presents in various forms. Its increasing incidence indicates that modern lifestyle triggers disease in genetically susceptible individuals. We present a model for inflammatory bowel disease pathophysiology and review the new biological therapies available. These biological agents have been developed to antagonise the processes of pathogenic inflammation, such as the reduction in T-lymphocyte apoptosis, increase in T-lymphocyte proliferation and increase in T-lymphocyte trafficking into the intestinal mucosa. Inhibitors of various inflammatory cytokines, including some antagonists to tumour necrosis factor, are effective therapies for inflammatory bowel disease. However, this class is associated with the risk of rare, but serious, side-effects, such as opportunistic infections and demyelinating diseases. The administration of anti-inflammatory cytokines, including interleukin-10 and interleukin-11, may theoretically be effective in reducing inflammation, although the clinical development of some of these therapies has been terminated. The selective inhibition of the adhesion molecules involved in T-lymphocyte trafficking can be effective in reducing gut inflammation. Of the selective adhesion molecule inhibitors under investigation, natalizumab has demonstrated efficacy in inflammatory bowel disease. The future of biological therapy for inflammatory bowel disease shows promise.

C/T polymorphism of the intercellular adhesion molecule-1 gene (exon 6, codon 469). A risk factor for coronary heart disease and myocardial infarction

BACKGROUND

The intercellular adhesion molecule-1 (ICAM-1) mediates the interaction of activated endothelial cells with leukocytes and plays a fundamental role in the pathogenesis of coronary atherosclerosis. ICAM-1 single-base C/T polymorphism, which determines an amino acid substitution in the ICAM-1 protein in exon 6 codon 469, has been described. Our purpose was to determine whether this C/T polymorphism influences the risk of coronary heart disease (CHD) and myocardial infarction (MI) in humans.

METHODS AND RESULTS

We enrolled 349 patients with angiographically documented CHD, including a sub-group of 179 patients with acute or chronic MI. The control group consisted of 213 patients with normal left ventricular function and no documented evidence of CHD. All patients and controls were Germans genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for the ICAM-1 polymorphism. In the patients with CHD and MI the frequencies of the T genotype (TT+TC) were significantly higher than the CC genotype compared to the control subjects (P<0.001). With the additional use of multivariable logistic regression analysis for CHD (TT+TC versus CC; P=0.011, odds ratio 2.21, 95% CI 1.20-4.07), we found a significant association between CHD and MI and the TT and TC genotype of the ICAM-1 gene polymorphism.

CONCLUSIONS

These results suggest that the TT and TC genotype of the ICAM-1 gene polymorphism in codon 469 is a genetic factor that may determine an individual's susceptibility for CHD and MI.

Etiopathogenesis of inflammatory bowel disease: the importance of the pediatric perspective

Inflammatory bowel disease (IBD) is now recognized as a common chronic disease affecting children and adolescents. This article will review recent advances made in the fields of genetics, epidemiology, gut ecology, and immunology regarding the etiopathogenesis of IBD, with particular emphasis on the contributions made by pediatric studies. Areas where further study of the pediatric age group would be beneficial will be highlighted.

Polymorphisms of the ICAM-1 gene are associated with inflammatory bowel disease, regardless of the p-ANCA status

The intercellular adhesion molecule-1 (ICAM-1) is of paramount importance for the initiation and propagation of various inflammatory conditions. An increased frequency of allele R241 of the ICAM-1 gene was previously described in p-ANCA-negative as compared to p-ANCA-positive ulcerative colitis and vice versa in Crohn's disease. One hundred sixteen healthy unrelated controls, 121 patients with ulcerative colitis, and 96 patients with Crohn's disease were genotyped for two polymorphisms of the ICAM-1 gene (R/G241, exon 4; and K/E469, exon 6), employing dot-blot hybridization and stratified according to their p-ANCA status. When compared with the control group the frequency of the allele R241 (P = 0.024) and the heterozygous genotype R/G241, P = 0.032) were significantly increased in ulcerative colitis, whereas the homozygous genotype G/G241 was found less frequently (P = 0.022). The heterozygous genotype K/E469 was observed less frequently (P = 0.001 and 0.037, resp.) than the homozygous genotype E/E469, which was more frequent in Crohn's disease and ulcerative colitis (P = 0.002 and 0.012, respectively). Further significant differences concerning the allele or genotype distribution were not observed. After stratification for the p-ANCA status significant differences concerning the frequencies of both the R241 and the E469 alleles were not detected when p-ANCA-positive inflammatory bowel disease and p-ANCA-negative inflammatory bowel disease were compared. Ulcerative colitis and Crohn's disease are associated with polymorphisms of the ICAM-1 gene, which might therefore represent a functional candidate gene. However, the observed associations are independent of the p-ANCA status.

Novel SNPs in the CD18 gene validate the association with MPO-ANCA+ vasculitis

Wegener granulomatosis (WG), microscopic polyangiitis (MP), and Churg-Strauss syndrome (CSS) are characterized by the presence of anti-neutrophil cytoplasmic antibodies (ANCA). Anti-myeloperoxidase (MPO)-ANCA are a typical feature of MP and CSS, while anti-proteinase 3 (PRTN3)-ANCA are highly specific for WG. Several reports indicate that ANCA may directly contribute to pathological processes, ie, through an increase of adhesivity between polymorphonuclear (PMN) and endothelial cells (EC). PMN interact and endothelium interact via the adhesion cascade (AC). CD18 is a key molecule of the AC, as CD18 defects abrogate the adhesion of PMN and cause leukocyte adhesion deficiency, an immunodeficient trait. We have screened the entire coding and regulatory regions of the CD18 gene. Ten single nucleotide polymorphisms (SNP) were identified, four of them showing significant associations with MPO-ANCA(+) vasculitis. One of these SNP's was localized in an alternate transcription initiation site. This polymorphism may influence CD18 gene expression, resulting in dose-dependent increase in adhesion and consecutively facilitated degranulation and respiratory burst. In this manner the pro-adherent genotype may predispose to MPO-ANCA(+) vasculitis.

Crohn disease: susceptibility and disease heterogeneity revealed by HLA genotyping

Predisposition to Crohn disease (CD) seems to be genetically determined but, though several reports on the matter, the association between HLA antigens and the disease is still controversial. PCR-SSP high resolution typing in 107 CD patients, and in subgroups selected according to clinical features, showed a positive association with the rare haplotype DRB1*07, DQB1*0303 both in the overall patients (p = 0.002; pc = ns) and in the subgroup of nonfistulized patients (p = 0.0008; pc = 0.032). Moreover, the protective role of the haplotype DRB1*03, DQB1*0201 (p = 0.029) was confirmed also in Italian patients, whereas no strong association with HLA class I alleles has been found. In addition, variability of the HLA alleles frequency in CD subgroups was observed, supporting the hypothesis of a genetic heterogeneity of the disease and suggesting that HLA alleles distribution in selected groups may allow to identify patients with probably different prognosis or associated complications.

Identification of ICAM-1 polymorphism that is associated with protection from transplant associated vasculopathy after cardiac transplantation

Transplant associated coronary disease (TxCAD) is the main cause of late graft loss following cardiac transplantation. It is a multifactorial disease with immunologic and nonimmunologic components involved. This study was undertaken to analyze the gene polymorphism in adhesion molecules in donors and recipients and to investigate its potential association with the development of TxCAD. A total of 82 cardiac transplant patients, 96 donors and 101 UK controls, were genotyped retrospectively. Nine nucleotide polymorphisms in L-selectin, E-selectin, ICAM-1, and PECAM were analyzed using allele-specific PCR-SSP assay. Recipients were selected on the basis of the development of TxCAD: patients who had developed TxCAD within 2 years after transplantation, and patients who did not have TxCAD within 4.5-5 years after transplantation. All recipients received CyA and azathioprine as a primary immunosuppression. Associations were assessed by using Fisher's exact test. No association was found between E-selectin, L-selectin, and PECAM allele or genotype frequencies and TxCAD. However, the donors whose recipients did not develop TxCAD at first 2 years had a significant increase of ICAM-1 E-469 allele compared with donors, whose recipients developed TxCAD (63.8% vs 46.4%, p = 0.042) and to UK controls (63.8% vs 47%, p = 0.04). Moreover, we found that the decreased frequency of ICAM E469 allele was associated with the increased number of rejection episodes. The 469 E/K polymorphism is in exon 6 and results in a change from glutamic acid to lysine in Ig-like domain 5 of ICAM-1, which is thought to affect interactions with LFA-1 and adhesion of B-cells. Our data suggest the presence of allele E469 ICAM-1 in either donor or recipient is protective against allograft rejection in a transplant setting.

Recent advances in inflammatory bowel disease

The last decade has seen tremendous advances in our knowledge, which has led to genuine improvements in our understanding of the pathogenesis and management of inflammatory bowel disease (IBD). The combined power of cellular and molecular biology has begun to unveil the enigmas of IBD, and, consequently, substantial gains have been made in the treatment of IBD. Refinements in drug formulation have provided the ability to target distinct sites of delivery, while enhancing the safety and efficacy of older agents. Simultaneous progress in biotechnology has fostered the development of new agents that strategically target pivotal processes in disease pathogenesis. This article addresses our current understanding of the pathogenesis of IBD, including the latest developments in animal models and covers agents currently used in the treatment of IBD as well as emerging therapies.

Delta 32 mutation of the chemokine-receptor 5 gene in inflammatory bowel disease

The gene encoding chemokine receptor 5 (CCR5) is colocalized to the microsatellite marker D3S1573, which was linked with inflammatory bowel disease. Genetic heterogeneity in inflammatory bowel disease might be defined by a combination of the p-ANCA status and immunoregulatory genes. One hundred and twenty healthy unrelated controls, 101 patients with Crohn's disease, and 99 patients with ulcerative colitis were genotyped for the Delta 32 mutation of the CCR5 gene. The presence of p-ANCA was determined by the use of indirect immunofluorescence. After genotyping, patients were stratified according to p-ANCA status. The frequency of the Delta 32 mutation was not significantly different in controls and patients with Crohn's disease or ulcerative colitis (P 0.207 or more). Moreover, the frequency of the mutation was not significantly different in patients with inflammatory bowel disease after stratification for the p-ANCA status (P 0.482). Regardless of the p-ANCA status, Crohn's disease and ulcerative colitis are not associated with the Delta 32 mutation of the CCR5 gene.