Lack of association between the TNFalpha G -308 A promoter polymorphism and periodontal disease

BACKGROUND

Immunorelevant gene polymorphisms might influence the susceptibility for periodontal disease. The present study assessed the frequency of a promoter polymorphism (-308G-to-A) of the tumour necrosis factor (TNF)alpha gene in patients with periodontitis and controls.

METHODS

Eighty-one patients with generalized chronic periodontitis and 80 healthy controls were genotyped for the -308 polymorphism of the TNF alpha gene by PCR amplification and subsequent restriction fragment length polymorphism analysis. The diagnosis of chronic periodontitis was made for each subject on basis of standardized clinical and radiographic criteria.

RESULTS

In patients with peridontitis and controls, the frequency of the TNF alpha-308 A allele was comparable (19.1% [31/162] versus 13.8% [22/160]; p=0.193).

CONCLUSION

The present study revealed no association between the -308 TNF alpha gene polymorphism and periodontal disease.

No significant association between mutations in exons 6 and 8 of the autoimmune regulator (AIRE) gene and inflammatory bowel disease

Various autoantibodies have been described in patients with inflammatory bowel disease. The autoimmune regulator (AIRE) functions as a transcription factor in cells responsible for the induction and maintenance of immunological tolerance. In contrast to classic autoimmune disorders, polymorphisms of the AIRE gene are not associated with inflammatory bowel disease, despite the presence of disease-specific autoantibodies.

Toll-like receptor (TLR) 2 and 4 mutations in periodontal disease

Toll-like receptors (TLR) are signal molecules essential for the cellular response to bacterial cell wall components. Different functional effective polymorphisms for the TLR 4 gene (Asp299Gly; Thr399Ile) and for the TLR 2 gene (Arg677Trp, Arg753Gln) have recently been described that are associated with impaired lipopolysaccharide signal transduction. A total of 122 patients with chronic periodontal disease and 122 healthy unrelated controls were genotyped for the Asp299Gly and Thr399Ile polymorphism of the TLR 4 gene and the Arg677Trp and Arg753Gln mutation of the TLR 2 gene. The mutations were identified with polymerase chain reaction followed by restriction fragment length polymorphism (RFLP) analysis. The prevalence of the Asp299Gly and the Thr399Ile mutant allele was 4.1% (10/244) and 4.5% (11/244) among periodontitis patients. For the healthy controls the prevalence was 3.3% (8/244) for the Asp299Gly (P = 0.810) and 3.7% (9/244) for the Thr399Ile mutant allele (P = 0.819). The Arg753Gln mutant allele was found in 2.9% (7/244) of the periodontitis subjects as compared to 4.1% (10/244) in the control group (P = 0.622). The Arg677Trp mutant allele was not found in any of the study subjects. Unlike in ulcerative colitis there was not observed an association between chronic periodontitis and the various mutations of the TLR 2 and 4 gene.

A polymorphism of the NFKBIA gene is associated with Crohn's disease patients lacking a predisposing allele of the CARD15 gene

BACKGROUND AND AIMS

Nuclear factor kappa-B (NFkappaB) plays a crucial role in diseases associated with dysregulated immune response. NFkappaB inhibitor alpha downregulates the activity of NFkappaB.

PATIENTS AND METHODS

To evaluate the contribution of the NFkappaB inhibitor alpha gene in Crohn's disease single nucleotide polymorphisms in the 3'-UTR and at position -420 in the promoter were studied in 259 patients with Crohn's disease genotyped for the variations of the CARD15 gene in comparison to 441 healthy controls. Additionally we screened the coding region of the NFkappaB inhibitor alpha gene for polymorphisms by SSCP analysis.

RESULTS

In comparison to controls the A allele and the AA genotype frequencies of the single nucleotide polymorphisms in the 3'-UTR were significantly increased only in Crohn's disease patients without a variation in the CARD15 gene. Similarly, the difference between patients harboring no predisposing CARD15 alleles and patients harboring such a variation was significant.

CONCLUSION

The findings indicate that the phenotype Crohn's disease is to be substructured with respect to genetic susceptibility.

Response to combination therapy with interferon alfa-2a and ribavirin in chronic hepatitis C according to a TNF-alpha promoter polymorphism

BACKGROUND

Tumor necrosis factor-alpha (TNF-alpha) is involved in the pathogenesis of chronic active hepatitis C. Polymorphisms in the promoter region of the TNF-alpha gene can alter the TNF-alpha expression and modify the host immune response. The present study aimed at the correlation of the G308A TNF-alpha polymorphism with the response to antiviral combination therapy in chronic hepatitis C.

PATIENTS AND METHODS

62 patients with HCV and 119 healthy unrelated controls were genotyped for the G308A TNF-alpha promoter polymorphism. The patients received 3 x 3 million units of interferon alfa-2a and 1,000-1,200 mg ribavirin daily according to their body weight. A response was defined as absence of HCV-RNA and normalization of S-ALT after 6 months of combination therapy.

RESULTS

With respect to the allele and genotype frequency, a significant difference was not observed between controls and patients with chronic hepatitis C. Furthermore, such a difference was also not observed if responders and non-responders to antiviral therapy were compared.

CONCLUSIONS

The promoter polymorphism of the TNF-alpha gene investigated herein is equally distributed in healthy individuals and patients with hepatitis C and does not seem to predict the response to therapy with interferon alfa-2a and ribavirin.

Prevalence of the chemokine receptor CCR5-Δ32 gene mutation in periodontal disease

A 32-base-pair deletion in the CCR5 gene was previously shown to influence the susceptibility for several infectious diseases. The present study compared the frequency of the CCR5-Delta32 mutation among subjects with periodontal disease and healthy control individuals. The prevalence of the CCR5-Delta32 mutation was determined in 81 patients with generalized periodontitis and 121 healthy controls. Standardized clinical and radiographic criteria were used for the diagnosis of periodontitis for each subject. The CCR5-Delta32 mutation was identified by PCR amplification and subsequent agarose gel electrophoresis. Genotype and allele frequencies among both study groups were compared using Fisher's exact test at a level of significance of 5% (P<0.05). The frequency of the CCR5-Delta32 allele was 9.9% (16/162) for periodontitis patients and 10.7% (26/216) for the healthy controls. The allele frequencies between periodontitis patients and the control group for the CCR5-Delta32 mutation were not significantly different (P=0.801). The present study revealed no association between the CCR5-Delta32 mutation and susceptibility to periodontal disease.

Interaction of polymorphisms in the CARD15 and CD14 genes in patients with Crohn disease

BACKGROUND

Associations of variations in the CARD15 gene (Arg702Trp, Gly908Arg and Leu1007fsinsC) and Crohn disease (CD) have been shown recently. These variations are neither necessary nor sufficient for the genetic predisposition of CD. Further genetic and environmental factors play a crucial role in the pathogenesis of CD.

METHODS

To evaluate putative interactions between the CARD15 and CD14 genes in CD, a functionally relevant polymorphism in the promoter region (T/C at position -159) has been genotyped for 650 healthy controls and 253 patients with CD by RFLP analyses. CD patients were genotyped for the variations of the CARD15 gene.

RESULTS

T allele and TT genotype frequencies of the CD14 promoter were significantly increased only in CD patients with at least one variation in the CARD15 gene compared to controls (P = 0.02 and 0.0002, respectively). No significant association was found in CD patients without any of the variations.

CONCLUSION

Interactions of the CARD15 and CD14 genes, both of which are involved in the recognition of lipopolysaccharides, increase the risk for developing CD.

The Delta 32 mutation of the chemokine-receptor 5 gene neither is correlated with chronic hepatitis C nor does it predict response to therapy with interferon-alpha and ribavirin

Unlike in HIV, homozygosity for a 32-bp deletion (Delta 32) of the chemokine receptor 5 (CCR5) gene was recently described in increased frequency in patients with chronic hepatitis C (HCV). Thus, it was speculated that this mutation might be relevant for disease susceptibility and influence the response to antiviral therapy. The present study sought to confirm the association between HCV and the Delta 32 mutation of the CCR5 gene and to correlate it with the response to therapy with interferon-alpha-2a and ribavirin. Sixty-two patients with HCV and 119 healthy unrelated controls were genotyped for the Delta 32 mutation. For the correlation between the Delta 32 mutation and response to therapy, only patients (n = 59) who completed 6 months of combination therapy as part of a prospective study were evaluated. The Delta 32 mutation was not observed in increased frequency in HCV. Furthermore, a significant difference of the HCV load or aminotransferase concentrations was not observed in carriers versus noncarriers of the Delta 32 mutation. After stratification for potentially confounding factors such as gender or HCV genotype, a significant difference was also not detected with respect to treatment outcome. These observations argue strongly against a role of CCR5 for susceptibility to HCV infection or response to combination therapy.

Crohn's disease: an immunodeficiency?

Autoimmunity appears to be a key factor in Crohn's disease as it develops in a genetically susceptible host if the immunological tolerance towards bacterial antigens within the gastrointestinal tract is abrogated. The resulting excessive immunological activity leads to a chronic sometimes transmural inflammatory process within the bowel wall. However, several lines of evidence are compatible with an immunodeficiency preceding these processes: humoral or cellular immune defects can predispose to inflammatory bowel disease. An increased bacterial adherence at the intestinal mucosa, which is possibly attributable to impaired expression of defensins was observed in Crohn's disease. Furthermore, the 3020insC mutation of the NOD2/CARD15 gene which is associated with Crohn's disease results in impaired cytokine transcription. Lastly, therapeutic approaches such as the use of antibiotic therapy or granulocyte macrophage colony stimulating factor are in line with the concept of an immunodeficiency being a crucial element in Crohn's disease.

Gastric emptying of solid and liquid meals in healthy controls compared with long-term type-1 diabetes mellitus under optimal glucose control

BACKGROUND

Neuropathy of the enteric nervous system and hyperglycaemia are regarded as the main causes of diabetic gastroparesis.

PATIENTS AND METHODS

In ten patients with Type-1 diabetes mellitus and sensomotoric neuropathy gastric emptying half times were compared with ten healthy controls by employing the 13C-octanoic acid and the 13C-sodiumacetate breath test, resp., following the intake of equally composed and isocaloric liquid and solid meals. Plasma glucose concentrations were controlled by permanent intravenous administration of insulin.

RESULTS

In diabetes mellitus gastric emptying half times after the intake of the liquid meal (p < 0.05) but not after ingestion of the solid meal were slightly prolonged. Gastric emptying half times in patients and controls were not different when liquid and solid meals were compared.

CONCLUSIONS

Acute hyperglycaemia appears to be more important than the neuropathy of the enteric nervous system in the pathophysiology of diabetic gastroparesis. The rate of gastric emptying is obviously not dependent on the phase of a meal, but rather on the composition and the caloric content.

Candidate genes colocalized to linkage regions in inflammatory bowel disease

BACKGROUND/AIMS

The genes encoding for tumor necrosis factor-alpha (TNF-alpha), epidermal growth factor receptor (EGFR) and the vitamin D receptor (VDR) are colocalized to inflammatory bowel disease-associated linkage regions on chromosomes 6, 7 and 12. An association study of these gene polymorphisms with ulcerative colitis or Crohn's disease and a stratification according to disease phenotypes was performed in order to identify genetically homogenous subgroups.

PATIENTS AND METHODS

119 healthy, unrelated controls, 95 patients with Crohn's disease and 93 patients with ulcerative colitis were genotyped for the (G to A) -308 TNF-alpha promoter polymorphism on chromosome 6, the codon 497 EGFR polymorphism on chromosome 7 and the TaqI polymorphism of the VDR gene on chromosome 12. After genotyping, patients were stratified according to the respective disease phenotype.

RESULTS

A disequilibrium in the distribution of the VDR genotypes was found in patients with ulcerative colitis compared to controls (p = 0.024). In fistulizing and fibrostenotic Crohn's disease the 'TT' genotype was significantly reduced compared with other phenotypes (p = 0.006), whereas the 'tt' genotype was found more frequently (p = 0.04). The frequency of the WT allele of the EGFR gene was significantly higher in ulcerative colitis (p = 0.04) than in controls. Further significant differences, concerning the associations of the different polymorphisms and disease susceptibility or clinical phenotypes, were not observed.

CONCLUSIONS

Regardless of the disease phenotype, the associations between the polymorphisms and inflammatory bowel disease investigated herein are modest, even after stratification for the disease phenotypes. Hence, these polymorphisms are unlikely to confer the reported linkage between inflammatory bowel disease and chromosomes 6, 7 and 12.

[Impact of 24-hour intraesophageal pH monitoring with 2 channels in the diagnosis of reflux-induced otolaryngologic disorders]

BACKGROUND

Patients with gastroesophageal reflux disease (GERD) may suffer from a large variety of symptoms in the upper aerodigestive tract such as globus sensation, chronic cough, hoarseness and many others. Diagnosis and causal therapy may sometimes be difficult with gastroenterologic evaluation sometimes revealing no pathologic result. The objective of this study was to determine the impact of 24-hour intraesophageal pH monitoring with 2 channels (gastric and laryngeal) in the diagnosis of reflux-induced otolaryngologic disorders.

METHODS

This study included 22 patients presenting to the Department of Otolaryngology with symptoms like chronic cough (n = 3), globus sensation and dysphagia (n = 11), heartburn (n = 2), hoarseness and dysphonia (n = 2) or burning sensation of the tongue (n = 1). Three patients had a pathologic formation in the glottic area (leukoplakia, granuloma, polyp). All patients underwent a otolaryngological examination, a gastroenterological investigation and a 24-hour intraesophageal pH monitoring with 2 channels.

RESULTS

All 22 patients showed laryngeal mucosal lesions (posterior laryngitis). The gastroenterological evaluation with esophagogastroduodenoscopy was normal in 4 cases. 13 patients showed a hiatal hernia, 4 patients were suffering from a reflux-esophagitis grade I and 2 patients from grade II. One patient had an erythema and 5 patients showed erosions of the gastric mucosa. Seven patients had more than one of the above mentioned diagnoses. Intraesophageal pH-monitoring with 2 channels over 24 hours revealed a gastroesophageal reflux of all 22 patients and a high reflux to the laryngeal level of 21 patients, probably causing laryngopharyngeal symptoms. Therapy of the patients consisted of medical antireflux treatment with proton pump inhibitor esomeprazol (Nexium, 40 mg, 1-0-0). Within 4 weeks 15 of 22 patients had no more laryngopharyngeal symptoms or at least a significant reduction.

CONCLUSION

Patients with laryngopharyngeal symptoms such as hoarseness, globus sensation or dysphagia can suffer from GERD, even if typical symptoms such as heartburn or retrosternal pain do not exist and gastroesophageal intervention reveals a normal result. The best diagnostic instrument for the diagnosis of reflux-induced otolaryngologic disorders is a 24-hour intraesophageal pH-monitoring with 2 channels (measure-points at the distal esophagus and laryngeal level). Medical antireflux treatment should consist of proton pump inhibitors (e. g. Nexium) in a dose of 40 mg per day over at least 4 weeks.

Anti-saccharomyces cerevisiae antibodies in patients with inflammatory bowel disease and their first-degree relatives: potential clinical value

Anti-Saccharomyces cerevisiae antibodies (ASCA) have been described as specific markers in Crohn's disease and their healthy first-degree relatives. 171 patients with Crohn's disease, their 105 first-degree relatives, 145 patients with ulcerative colitis and 101 first-degree relatives of patients with ulcerative colitis, 50 patients with infectious enterocolitis and 100 healthy controls were tested for ASCA employing the ELISA technique. When compared with the healthy controls (p < 0.0001) and patients with infectious enterocolitis (p < 0.0001) the prevalence of ASCA was significantly increased in patients with Crohn's disease and their first-degree relatives (p < 0.01). Further significant differences concerning the frequency of ASCA within the different groups of our study population were not observed. In particular, ASCA were not found in increased prevalence in infectious enterocolitis. These observations are compatible with a role of ASCA as a marker of genetic predisposition to Crohn's disease.