Positive association of genetic variants in the upstream region of NKX2-3 with Crohn's disease in Japanese patients.

BACKGROUND AND AIMS: A number of genome-wide association studies have been performed as a robust means of identifying susceptibility loci for Crohn's disease (CD). The loci detected after the completion of the HapMap project are quite concordant among these studies, suggesting that the results are reliable. Recently, the Wellcome Trust Case Control Consortium (WTCCC) reported the primary scanning of 17,000 individuals for seven diseases, including CD, and a subsequent study has validated these susceptible genetic variants in independent UK sample sets. The purpose of this study was to study the possible association of the variants reported by the WTCCC with CD in a Japanese population. PATIENTS AND METHODS: A total of 484 patients with CD and 470 healthy controls were examined. Seventeen genetic variants at eight newly identified loci, including IRGM, NKX2-3 and PTPN2, were genotyped using the TaqMan assay or the invader assay. RESULTS: A positive association signal presumably common to different ethnic groups for rs10883365 was detected in the upstream region of NKX2-3 (p = 0.019 under the genotypic model, p = 0.0065 under the allelic model, p = 0.019 under the recessive model, p = 0.036 under the dominant model). In addition to rs10883365, marginal associations for two single nucleotide polymorphisms (SNPs) were detected in the Japanese population; rs6887695 near IL12B and rs10761659 on 10q21. Further genotype-phenotype analysis found a significant association between rs6887695 and patients with pure ileal CD. CONCLUSIONS: The results indicate that the three loci are possible candidates for conferring susceptibility to CD in people of different ethnicities.

Genetic polymorphisms of tumour necrosis factor receptor superfamily 1A and 1B affect responses to infliximab in Japanese patients with Crohn's disease.

BACKGROUND: Tumour necrosis factor alpha is the key inflammatory cytokine involved in the pathogenesis of Crohn's disease. Infliximab, a chimaeric monoclonal antibody of tumour necrosis factor-alpha is successfully used for the treatment of Crohn's disease, although the response to infliximab therapy differs among patients. The genetic background of the individual may partially explain the differences of the responsiveness. AIM: To investigate whether the polymorphisms in these genes are associated with the response to infliximab treatment as tumour necrosis factor-alpha exerts its biological activity through TNF receptor superfamily 1A and 1B. METHODS: Eighty Crohn's disease patients were enrolled in the study and classified into responder and nonresponder according to the efficacy of infliximab treatment. Single nucleotide polymorphisms of TNF receptor superfamily 1A (rs767455 and rs4149570) and TNF receptor superfamily 1B (rs1061622, rs1061624 and rs3397) were determined. RESULTS: The minor allele carrier of rs767455 showed a significant association with a lack of efficacy compared to the major genotype (OR = 0.26; 95% CI: 0.08-0.91). A TNF receptor superfamily 1B haplotype inferred by rs1061624 and rs3397 also showed significant differences in the distribution between responder and nonresponder (P = 0.01). CONCLUSION: These results suggest that tumour necrosis factor receptor genotypes may be involved in the different responses to infliximab in Japanese patients with Crohn's disease.

A randomised dose finding study of oral tacrolimus (FK506) therapy in refractory ulcerative colitis.

BACKGROUND AND AIMS: Immunosuppressive therapy with intravenous ciclosporin is an alternative treatment option to total colectomy for patients with ulcerative colitis (UC), while the benefits of oral administration of tacrolimus are not well defined and are based on reports of several uncontrolled studies. METHODS: Patients with refractory active UC were randomly assigned to a high trough concentration (10-15 ng/ml) group (HT group) (n = 21), low trough concentration (5-10 ng/ml) group (LT group) (n = 22), or placebo group (n = 20). Patients received an initial oral dose of 0.025 [DOSAGE ERROR CORRECTED] mg/kg tacrolimus or placebo twice daily. Efficacy was evaluated in 60 patients based on a disease activity index (DAI) score. Fifty eight patients had additional treatment with tacrolimus and were evaluated for efficacy in a 10 week open label extension. RESULTS: An improvement in DAI score (>or=4 points, all categories improved) was observed for 68.4% of cases in the HT group compared with 10.0% in the placebo group (p<0.001). In the HT group, 20.0% of patients had clinical remission and 78.9% had mucosal healing. In the open label extension, 55.2% of all patients had an improved DAI score at week 10. Mean dose of prednisolone was reduced from 19.7 mg/day at study entry to 7.8 mg/day at week 10. The incidence of side effects in the HT group was significantly higher than that of the placebo group (p = 0.043). The most common event was mild finger tremor. CONCLUSIONS: Our findings demonstrate dose dependent efficacy and safety of oral tacrolimus for remission-induction therapy of refractory UC. The optimal target range appears to be 10-15 ng/ml in terms of efficacy with two week therapy.

A case of perforation and fistula formation resulting from metallic stent for sigmoid colon stricture in Crohn's disease.

A 52-year-old male was diagnosed with Crohn's disease at the age of 25 years. Thereafter, he underwent three operations for intestinal strictures or fistula. A self-expanding metallic stent was inserted into the sigmoid colon stricture endoscopically in November 1999. Thirty two months later, he presented left lower abdominal pain. Endoscopic and radiographic examinations demonstrated perforation of the stent and ileosigmoid fistula. Laparotomy revealed an inflammatory mass around the sigmoid colon, and the wire frame of the metallic stent had penetrated the colonic wall and had fistulized to the ileum. The affected sigmoid colon was resected and low anterior resection and ileostomy were performed. Metallic stent for intestinal stricture of Crohn's disease with active ulceration may postpone surgery temporarily but can be a potentially dangerous procedure.

Association between K469E allele of intercellular adhesion molecule 1 gene and inflammatory bowel disease in a Japanese population.

BACKGROUND AND AIMS: The genetic contribution to inflammatory bowel disease (IBD) is under investigation. Recent evidence indicates a significant linkage between a locus on chromosome 19p13 and IBD. We investigated the association between an intercellular adhesion molecule 1 gene (ICAM-1) polymorphism located on chromosome 19p13 and IBD in a Japanese population. METHODS: We compared 207 Japanese patients who had IBD (79 with Crohn's disease (CD); 128 with ulcerative colitis (UC)) with 103 unrelated Japanese controls. We determined R241G and K469E polymorphisms of the ICAM-1 gene using polymerase chain reaction (PCR) techniques. RESULTS: Both frequency and carriage rate of the K469 allele were significantly higher in IBD patients than in controls (allelic frequency, p(c)=0.0026; carriage rate, p(c)=0.0034; odds ratio 2.59; 95% confidence interval 1.42-4.68). Furthermore, the frequency of the K469 allele was significantly increased in both CD and UC. Subgroup analysis demonstrated that both K469 allelic frequency and K469 carriage rate were significantly higher in patients with the small bowel and colon type of CD and entire colitis compared with healthy controls. CONCLUSIONS: We identified an overall association between IBD and ICAM-1 K469 in a Japanese population. Further studies of this chromosome region are required to elucidate the gene responsible for IBD.

Polymorphisms of human CD19 gene: possible association with susceptibility to systemic lupus erythematosus in Japanese.

CD19 regulates the signaling for B lymphocyte development, activation and proliferation. In mice, CD19 deficiency and overexpression were shown to result in hypogammaglobulinemia and autoantibody production, respectively. In the present study, we screened for the polymorphisms of CD19, and examined the detected polymorphisms for the association with rheumatoid arthritis (RA), Crohn's disease and systemic lupus erythematosus (SLE). Two SNPs, c.705G>T (P235P and IVS14-30C>T, were decreased (P = 0.0096 and P = 0.028, respectively), in SLE. A GT repeat polymorphism, c.*132(GT)(12-18), was detected within the 3'-untranslated region, and individuals with > or =15 times repeat was significantly increased in the independent two groups of Japanese SLE patients (P = 0.011 and P = 0.035, respectively); the overall difference between total SLE and controls was striking (P = 0.0061). No association was observed for RA and Crohn's disease. In addition, no variations other than the common polymorphisms were detected in four patients with common variable immunodeficiency, the phenotype of which resembles CD19 deficient mice. In Caucasian SLE families, this GT repeat polymorphism was rare. CD19 mRNA level in the isolated peripheral blood B lymphocytes was lower in individuals possessing (GT)(15-18) alleles compared with those without these alleles, both in controls and in SLE patients; however, the difference did not reach statistical significance. These results suggested that either the slight reduction in the CD19 mRNA level associated with the elongation of GT repeat, or an allele of another locus in linkage disequilibrium with CD19 (GT)(15-18), may be associated with susceptibility to SLE in Japanese.

Efficacy of treatment with chimeric monoclonal antibody (Infliximab) to tumor necrosis factor-alpha for Crohn's disease in Japan: evaluation by rapid turnover proteins, and radiologic and endoscopic findings.

BACKGROUND: Several studies have reported that the chimeric monoclonal antibody to tumor necrosis factor (TNF)-alpha (Infliximab) is extremely valuable in the treatment of Crohn's disease. The aim of this study was to clarify the efficacy of this treatment in Japanese patients with Crohn's disease. METHODS: A 12-week multicenter, open trial of Infliximab was carried out and involved 25 patients with moderate to severe Crohn's disease who were resistant to conventional treatment. Patients received a single 2-h intravenous infusion of Infliximab at a dose of 1, 3, 5 or 10 mg/kg bodyweight. Clinical evaluation of this treatment response was defined as a reduction in the index of the inflammatory bowel disease (IOIBD) and of the Crohn's disease activity index scores (CDAI), and in serum levels of C-reactive protein (CRP) at 2, 4, 8 and 12 weeks, and as an increase in serum levels of rapid turnover proteins as well as improvement of radiologic and endoscopic findings at 4 weeks. RESULTS: The IOIBD score was reduced after 4 weeks in 66.7% of the group receiving 1 mg/kg Infliximab, 71.4% in the group receiving 3 mg/kg, 80.0% in the group receiving 5 mg/kg, and 85.7% in the group receiving 10 mg/kg. Improvement was better maintained over 12 weeks in the 5 and 10 mg/kg groups compared with the 1 and 3 mg/kg groups. Similar results were obtained for the CDAI scores. Serum levels of rapid turnover proteins significantly increased to within the normal ranges after infusion in all groups. Seven of the 11 (63.6%) patients evaluated showed improvement of radiologic and endoscopic findings. CONCLUSIONS: A single infusion of Infliximab was effective for the treatment of Japanese patients with Crohn's disease. Serum rapid turnover proteins reflected the clinical response to antibody for TNF-alpha well.

Effective maintenance leukocytapheresis for patients with steroid dependent or resistant ulcerative colitis.

We prospectively examined the effect of leukocytapheresis (LA) on the maintenance of remission in 7 patients with ulcerative colitis (UC) who were initially refractory to corticosteroid therapy (steroid resistant or steroid dependent). The patients with refractory UC had been in remission due to LA (induction LA) in combination with the steroid therapy. They were then treated with LA once or twice a month for the purpose of maintaining remission (maintenance LA). The maintenance LA was performed by either a centrifuge method in 5 patients or a polyester adsorbent column method in 2 patients. Steroid dosage was gradually tapered as little as possible without recurrence based on clinical and/or colonoscopical judgments. Four patients were maintained in remission without steroids over 12 months. Recurrence was observed in 3 patients at 3, 3, and 6 months after the beginning of the maintenance LA, respectively. Two of the 3 patients were again conducted to remission by the second induction LA and maintained in remission by the second maintenance LA. Two patients finally underwent total colectomy because of recurrence of UC in a severe form. It is concluded that the maintenance LA therapy might be effective in some patients with steroid dependent or resistant UC for the maintenance of remission without steroids.

Independent contribution of HLA-DRB1 and TNF alpha promoter polymorphisms to the susceptibility to Crohn's disease.

Although a number of studies reported the association of HLA-DRB1 and Crohn's disease (CD), the actual alleles associated with CD are considerably variable among populations. On the other hand, the relevance of tumor necrosis factor alpha (TNF alpha) in the pathogenesis of CD is established through experimental as well as clinical studies, raising the possibility that TNFA polymorphism is primarily or independently contribute to the association of HLA region genes with CD. New polymorphisms which may affect the transcriptional activity were recently reported within the upstream promoter region of TNFA gene. In the present study, we compared HLA-DRB1, TNFA promoter and TNF receptor 2 (TNFR2) genotypes in 154 Japanese patients with CD and 265 unrelated healthy controls to evaluate the individual contribution of these genes to the genetic predisposition to CD. Significant positive association was observed in HLA-DRB1*0405 (P = 0.001, odds ratio (OR) = 2.02) and 0410 (P = 0.002, OR = 4.79). Among the TNFA promoter haplotypes, TNFA-U03 (-1031C, -863A, -857C) was significantly increased (P = 0.008, OR = 1.64), while TNFA-U04 (-1031C, -863C, -857C) was significantly decreased (P = 0.014, OR = 0.12), in CD. The association with TNFA-U03 was independent of that with DRB1*0405 and 0410, and apparent additive or multiplicative effect was not observed between these susceptibility alleles. No association was observed between TNFR2-196M/R polymorphism and CD. These results indicated that both of HLA-DRB1 and TNFA promoter polymorphisms contribute to the susceptibility to CD in an independent manner.

[Team approach of Crohn's disease therapy].

Under the current conditions that etiologies of Crohn's Disease (CD) are not detected and then no radical therapy existed, it is necessary that the CD patients can be medically managed by not only medical doctors but also other co-medical staffs such as nurses, dietitians, social workers and ET (Enterostomal Therapist) nurses for their cure & care therapy. There are some different therapeutic steps; 1) Nutritional Therapy, 2) Drug Therapy, 3) Surgical Therapy and 4) Psychological (Mental) Support. In Japan, Nutritional Therapy headed by Elemental Enteral Nutrition is recommended as for 1st choice standard therapy for CD patients, who are mainly very young and are required to have themselves acceptable for long-term therapeutic controls. Thus, the medical support team shall be considerable enough to each patient's life back ground in order to give them the whole-mentally therapeutic approach.

Specific clonal T cell accumulation in intestinal lesions of Crohn's disease.

The initial cellular events that take place at the outset of autoimmune diseases and that may be the most important in terms of understanding their pathogenesis are poorly understood, especially in humans. This is mainly due to the difficulties in the identification of primary lesions and the accessibility to such material. In this respect, it is noteworthy that the appearance of small reddish erosions, known as aphthoid lesions, is known to be an early event in Crohn's disease. In the present study, accumulation of lesion-specific clonal TCR bands in the intestinal lesions of Crohn's disease patients was demonstrated by means of a highly sensitive method based on single strand conformational polymorphism. Such clonal accumulation was demonstrated in both aphthoid and discrete ulcer lesions. There were several TCR BV bands that were present in both aphthoid lesions and discrete ulcer lesions, but some were specific to the aphthoid lesions. In addition, the same aphthoid lesion-specific/dominant T cell clones were found to be expanded in separate aphthoid lesions of a single patient, and were absent from intervening, non-inflamed mucosa. Some of these bands may represent T cell clones activated primarily at the onset of disease.

HLA-linked susceptibility and resistance genes in Crohn's disease.

BACKGROUND & AIMS: Previous studies have shown a positive association of HLA-DR4-DQ4 with Crohn's disease in the Japanese population, but the association between Crohn's disease and HLA genes has yet to be fully elucidated. The aim of this study was to determine the Crohn's disease/HLA association using a DNA typing method. METHODS: A total of 90 unrelated patients with Crohn's disease and 336 healthy controls were typed for HLA class II genes including DP using DNA typing with the polymerase chain reaction-sequence-specific oligonucleotide probes method. RESULTS: Allelic analysis showed that DRB1*0405, DRB1*0410, DQA1*03, DQB1*0401, and DQB1*0402 are positively associated and DRB1*1501, DRB1*1302, and DQB1*0602 negatively associated with Crohn's disease. DP genes showed no significant association with Crohn's disease. Haplotype analysis showed positive associations with DRB1*0405-DQA1*03-DQB1*0401, DRB1*0410-DQA1*03-DQB1* 0402, and DRB1*0802-DQA1*03-BQB1-0402 haplotypes and negative associations with DRB1*1501-DQA1*0102-DQB1*0602 and DRB1*1302-DQA1*0102-DQB1*0604 haplotypes. CONCLUSIONS: In Crohn's disease in the Japanese population, the HLA-linked disease susceptibility gene is primarily associated with DQB1*04, in which leucine at the 56th position is a unique amino acid, and the disease resistance allele is suggested to be DQA1*0102.