Shoji Kuwata

Close Relationship of Abnormal Glucose Tolerance With Endothelial Dysfunction in Hypertension

Hypertension is frequently accompanied by left ventricular hypertrophy, endothelial dysfunction, and abnormal glucose metabolism. However, no study has examined the relative pathological significance of left ventricular hypertrophy and abnormal glucose metabolism on endothelial dysfunction in hypertension. This study was conducted to evaluate whether abnormal glucose tolerance assessed by 75-g oral glucose tolerance test or left ventricular hypertrophy is more closely associated with endothelial dysfunction in never-treated hypertensive patients without elevated fasting blood glucose. We studied 107 unmedicated hypertensive patients (mean age, 54+/-10 years) whose fasting blood glucose was <7.0 mmol/L. Endothelial function was assessed by change in brachial artery diameter in response to reactive hyperemia, and left ventricular mass index was determined by ultrasonography. Simple linear regression analysis demonstrated that endothelial function significantly correlated with left ventricular mass index and 2-hour blood glucose in 75-g oral glucose tolerance test, but not with fasting blood glucose. Multiple linear regression analysis revealed that endothelial function significantly correlated with 2-hour blood glucose (beta=-2.68, P<0.05) after we controlled for other clinical variables. Patients were divided into 3 groups according to 2-hour blood glucose levels. Endothelial function was more impaired in patients with diabetes (n=12; 4.7+/-1.8%) and in those with impaired glucose tolerance (n=31; 6.3+/-2.9%) than in those with normal glucose tolerance (n=64; 8.4+/-4.5%) (P<0.05), but left ventricular mass index was similar in these 3 groups. Abnormal glucose tolerance assessed by 75-g oral glucose tolerance test, rather than left ventricular hypertrophy, may have direct pathophysiological relevance to endothelial dysfunction in borderline to moderate hypertensive patients.

Genetic contribution of the tumour necrosis factor (TNF) B + 252*2/2 genotype, but not the TNFa,b microsatellite alleles, to systemic lupus erythematosus in Japanese patients

The contribution of the tumour necrosis factor (TNF) B + 252 (TNFB) dimorphism and microsatellite polymorphisms of TNFa and TNFb to the pathogenesis of systemic lupus erythematosus (SLE) was studied in Japanese patients. The TNFB dimorphism was determined using the restriction fragment length polymorphism (RFLP) method with NcoI digestion followed by specific polymerase chain reaction (PCR) amplification. TNFa and TNFb microsatellite polymorphisms were determined using the DNA sequencer and GeneScan program (Applera Corporation, Foster City, CA) followed by specific PCR amplification. HLA‐DRB1*15 typing was carried out by the PCR‐sequence specific conformational polymorphism (SSCP) method. In SLE, the allele frequency of TNFB*2 significantly increased (68.9%, P < 0.05) and the genotype frequency of TNFB*2/2 also increased (52.8%, P < 0.05). TNFB*2 showed no significant linkage disequilibrium with HLA‐DRB1*1501. The prevalence of TNFa13 and TNFb4 showed very slight increases, but these increases were not significant. An association analysis indicated that TNFB*2/2 conferred greater, or at least equal, susceptibility to SLE in Japanese patients in comparison with HLA‐DRB1*1501. The TNFB*2/2 genotype may contribute additively with DRB1*1501 to SLE in Japanese patients. No association was observed between auto‐antibodies and TNF. TNFB*2 is a genetic marker for SLE in Japanese patients, while TNFa and TNFb microsatellites are not associated with SLE.

Analysis of HLA class II and TAP alleles in Japanese patients with psoriasis vulgaris

We investigated HLA class II and transporter associated with antigen processing (TAP) alleles in eighty-five unrelated Japanese patients with psoriasis vulgaris and fifty-two healthy controls using the polymerase chain reaction-restriction fragment length polymorphism method. The frequencies of DRB1*1502 and DQB1*0601 were increased in the patient group (DRB1*1502; 21% vs 12%, p < 0.05, DQB1*0601; 35% vs. 21%, p < 0.05), while the frequencies of DRB1*0406 and TAP2*E were decreased in the patients (DRB1*0406; 2% vs 9%, p < 0.05, TAP2*E; 4% vs 11%, p < 0.05). However, none of these remained significant after p values were corrected for the number of comparisons made (pc > 0.05). We also analysed specific amino acids on HLA class II molecules, but no significant difference was found between the two groups. Our previous reports clarified that aspartate at residue 9 (48% vs 20%, p < 0.002) and alanine at residue 73 (81% vs 48%, p < 0.0001) on HLA-C molecules were strongly associated with Japanese patients with PsV. These specific amino acids on HLA-C molecules are supposed to play more important roles compared with HLA class II and TAP alleles in the development of psoriasis vulgaris.

Lack of CTGF*-945C/G Dimorphism in Thai Patients with Systemic Sclerosis.

An association between connective tissue growth factor (CTGF) gene dimorphism at –945 (CTGF*-945C/G) and systemic sclerosis (SSc) has been reported with inconclusive results. We performed this study to determine whether such an association exists among Thai patients with SSc. DNA samples were taken from 50 Thai SSc patients (diffuse SSc in 39 and limited SSc in 11) and 99 healthy controls for determination of CTGF*-945C/G dimorphism by polymerase chain reaction (PCR) using specific oligonucleotide primers. The associations between the genotype frequencies, clinical manifestations and auto-antibodies were determined as well. When compared with the controls, SSc patients had no significantly higher frequencies of the GG genotype (44.0% vs 39.4%, p = 0.60), G allele (63.0% vs 65.2%, p = 0.80) or G phenotype (82.0% vs 90.9%, p = 1.0). There was no association between the presence of the GG genotype and clinical manifestations (pulmonary fibrosis, sclerodactyly, digital pitting scars, telangiectasia and pulmonary arterial hypertension), or the presence of auto-antibodies (anti-Scl-70, anti-SSA/Ro, and anti-RNP). In conclusion, we found no association between CTGF*-945C/G dimorphism and Thai SSc patients.

The CTLA-4 −1661A/G and −1772T/C dimorphisms in Japanese patients with systemic sclerosis

Dear Sir, Systemic sclerosis (SSc) is a well known autoimmune disease characterized by various clinical features such as proximal scleroderma, bilateral pulmonary Wbrosis, and auto-antibodies. The possible contribution of genetic factors to SSc has been presented in several studies, though the etiology of SSc is still unclear. In Japanese, the HLA DRB1*1502-DRB5*0102 haplotype and DRB1*0802 were found to be associated with diVuse scleroderma and a-Scl-70-positive SSc [1]. For the pathogenesis of SSc, the contribution of immunological abnormalities was assumed. In the salivary glands of very early stage SSc, the expression of TNF has been observed prior to the onset of skin changes [2], and Koch et al. [3] reported an increased expression of cytokines and cellular adhesion molecules in the skin of patients with SSc. Cytotoxic T Lymphocyte associated-4 (CTLA-4) and CD28 on T cells, on the other hand, bind to CD80 and CD86 and the ligation of CTLA-4 blocks CD-28-dependent T cell activation and IL-2 accumulation [4]. The CTLA-4 molecule is thought to terminate the immune response by CD28 and to keep the homeostatic balance of the immune system, so CTLA-4 would therefore be an important negative regulator of autoimmune diseases [5]. Considering the immune regulatory function of CTLA-4, the CTLA-4 gene is an interesting candidate as a disease-susceptible gene or genetic marker. The CTLA-4 gene is located on chromosome 2q33, and dimorphisms are reported to be at positions ¡1661 and ¡1772 in the promoter region [6]. The former is a substitution of adenine to guanine (¡1661A/G), and the latter is a substitution of thymine to cytosine (¡1772T/C). Recently, we had reported an increase of the +49A allele of CTLA-4 in SSc with the anti-RNP antibody (a-RNP), though there was no association with the disease types of SSc, the anti-Scl-70 antibody (a-Scl-70), or the anti-centromere antibody (ACA) [7]. The associations of the CTLA-4 ¡1661 and ¡1772 dimorphisms with SSc have not been reported as of yet. On the other hand, associations of the CTLA-4 ¡1772 dimorphism with SLE were reported in Korean [6] and Spanish [8]. Here, we studied 61 unrelated Japanese SSc patients aged 52.7 § 11.3 years old (mean § SD) (59 women and 2 men) to clarify the contribution of the CTLA-4 ¡1661 and ¡1772 dimorphisms to Japanese SSc. Almost all patients with SSc had been reported in our previous report [7]. All patients fulWlled the criteria outlined by the American Rheumatism Association (ARA) in 1980. As controls, 104 randomly selected, unrelated, healthy subjects were compared. F. Takeuchi (&) 504 Laboratory, Department of Internal Medicine (Allergy and Rheumatology), Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan e-mail: fujio-tky@umin.ac.jp

The genetic contribution of CTLA‐4 dimorphisms in promoter and exon 1 regions in Japanese patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a well‐known autoimmune disease, but its aetiology remains obscure. Cytotoxic T lymphocyte associated‐4 (CTLA‐4) on T cells is thought to terminate the immune response ...

The genetic contribution of HLA‐DRB5*01:01 to systemic lupus erythematosus in Thailand

Human leucocyte antigen (HLA) study in patients with systemic lupus erythematosus (SLE) has been investigated in various countries, but the results are still inconclusive. This study was performed to investigate the association between HLA‐DR and SLE in patients in northern Thailand. HLA‐DR subtyping was performed in 70 patients with SLE and 99 normal healthy controls living in northern Thailand using the INNO‐LiPA HLA‐DR Decoder kit (Innogenetics) and MICRO SSP HLA DNA Typing kit (One Lambda) for reconfirmation. The allele frequency (AF) of DRB5*01:01 in SLE was significantly higher than in the controls [25.7% vs. 14.6%, P = 0.012, Pc = 0.048, OR = 2.02 (95%CI = 1.17–3.48)]. The AF of DRB1*15:01 and DRB1*16:02 showed a nonsignificant tendency to be higher in SLE (10.7% vs. 8.1%, and 17.9% vs. 11.1%). Interestingly, the DRB5*01:01 allele linked to DRB1*16:02 in 47.2% of SLE and 37.9% of controls, and the prevalence of the DRB1*16:02‐DRB5*01:01 haplotype was higher in the patients with SLE [12.1% vs. 5.6%, P = 0.044, OR = 2.35 (95%CI = 1.06–5.19)]. The DRB1*16:02 linked to DRB5*02:02 and *02:03 in 18.2% and 31.8% of controls, respectively, and linked to DRB5*02:03 in 32.0% of SLE patients. The frequency of DRB1*03:01 and *15:02 alleles was not increased in Thai SLE. There was no significant association between DRB5*01:01 and any auto‐antibodies or clinical manifestations of SLE. DRB5*01:01 is associated with Thai SLE, and the association is stronger than that of DRB1*15:01. The genetic contribution of DRB5*01:01 is due partially to the linkage disequilibrium between DRB1*16:02 and DRB5*01:01 in the northern Thai population.

Distribution of HLA-DR alleles among Thai patients with rheumatoid arthritis

OBJECTIVE This study was performed to investigate the association between the HLA-DR series and rheumatoid arthritis (RA) in a Thai population. METHODS HLA-DR subtypes were determined in 100 Thai RA patients and 99 healthy controls (HC). HLA-DR typing was performed using INNO-LiPA HLA-DRB Decoder kits (Innogenetics) and reconfirmed using MICRO SSP HLA DNA Typing kits (One Lambda) for DRB1(∗)02 and (∗)04. RESULTS When compared with the HC, the RA patients had higher allele frequency (AF) of DRB1(∗)04:05 (15.00% vs 7.07%, p=0.016, pc=NS, OR=2.319, 95%CI=1.189-4.522) and DRB1(∗)10:01 (3.00% vs 0%, p=0.030, pc=NS), respectively. The DRB1(∗)09:01 was slightly higher in the RA patients, without statistical significance. The AF of the shared epitope (SE) alleles (HLA-DRB1(∗)01:01, (∗)04:01, (∗)04:05 and (∗)10:01) was significantly higher in the RA patients (18.50% vs 7.58%, p=0.002, pc=0.046, OR=2.769, 95%CI=1.466-5.231, 99%CI=1.201-6.388). The AF of HLA-DRB4(∗)01 also increased significantly more in the RA patients (40.50% vs 25.76%, p=0.002, pc=0.002, OR=1.962, 95%CI=1.282-3.003, 99%CI=1.121-3.433). The HLA-DRB3(∗)03:01 was significantly lower in the RA patients (6.00% vs 14.14%, p=0.008, pc=0.023, OR=0.388, 95%CI=0.191-0.786, 99%CI=0.153-0.982). CONCLUSION In the presence of SE, the DRB1(∗)04:05 and HLA-DRB4(∗)01 were associated with RA, and the DRB3(∗)03:01 would be a protective allele against RA in a Thai population.