A novel method for isolation of endothelial cells and macrophages from murine tumors based on Ac-LDL uptake and CD16 expression

Analysis of specific properties of tumor endothelium should be useful for development of novel antiangiogenic strategies. However, the isolation of pure endothelial cells from tumor tissues is still a fundamental problem. In this study, we have attempted to develop a reliable method for the isolation of endothelial cells from murine tumors. We found that the labeling with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-acetylated-low density lipoprotein (Dil-Ac-LDL), commonly used for this purpose, can result in the contamination of isolated endothelium by macrophages due to the overlapping staining patterns of these two distinct cell types. Therefore, we chose the CD16, which is expressed on macrophages but not endothelial cells, to better distinguish them when labeled with Dil-Ac-LDL. By using this method, we obtained pure populations of endothelial cells and macrophages from murine colorectal cancer tissues, showing characteristic morphological and functional properties of the either cell type. The endothelial cells were long spindle-shaped, spread on gelatin, formed tube-like structures on Matrigel and expressed MECA-32 but not CD68. In contrast, the macrophages were round-shaped, partially spread on gelatin, formed unorganized aggregates on Matrigel and expressed CD68 but not MECA-32. The additional analysis of normal and tumor tissues revealed a positive correlation between the relative numbers of tumor endothelial cells and macrophages, calculated as % total cells, as well as the respective relative number and tumor weight. The present method is hoped to be useful for the evaluation of tumor angiogenesis and antitumor immunity.

Crucial role of inhibitor of DNA binding/differentiation in the vascular endothelial growth factor-induced activation and angiogenic processes of human endothelial cells

Angiogenesis plays a pivotal role in the aggressive proliferation of synovial cells in rheumatoid arthritis. We have previously reported the overexpression of inhibitor of DNA binding/differentiation (Id) in the endothelial cells within the synovial tissues of rheumatoid arthritis. In this study, we investigated the role of Id in inflammation and angiogenesis in an in vitro model using HUVECs. Vascular endothelial growth factor (VEGF) and TGFbeta induced the expression of Id1 and Id3 in HUVECs. Forced expression of Id induced proliferative activity in HUVECs accompanied by down-regulation of p16INK4a. Overexpression of Id enhanced expression of ICAM-1 and E-selectin, and induced angiogenic processes such as transmigration, matrix metalloproteinase-2 and -9 expression, and tube formation. In contrast, knockdown of Id1 and Id3 with RNA interference abolished proliferation, activation, and angiogenic processes of HUVECs induced by VEGF. These results indicated that Id plays a crucial role in VEGF-induced signals of endothelial cells by causing activation and potentiation of angiogenic processes. Based on these findings, it was proposed that inhibition of expression and/or function of Id1 and Id3 may potentially be of therapeutic value for conditions associated with pathological angiogenesis.

Follistatin-related protein gene (FRP) is expressed in the synovial tissues of rheumatoid arthritis, but its polymorphisms are not associated with genetic susceptibility

OBJECTIVE

To examine the expression level and function of follistatin-related protein gene (FRP, also referred to as FSTL1) in rheumatoid arthritis (RA), and possible association of its polymorphisms with genetic susceptibility to RA.

METHODS

FRP mRNA expression levels in the synovial tissues from 10 patients with RA and 5 patients with OA were measured using real-time RT-PCR. Effects on the growth of synovial cells were evaluated by stably introducing FRP cDNA into a rheumatoid synovial cell line, E11. Screening of genomic DNA variations was done using DNA from 12 patients with RA and 12 healthy individuals by direct sequencing. Genotypes at the detected polymorphic sites were determined in 224 patients with RA and 220 healthy individuals using PCR-single strand conformation polymorphism.

RESULTS

FRP mRNA was overexpressed in synovial tissues from RA patients by 2.3-fold as compared with those from OA. A rheumatoid synovial cell line (E11) transfected with FRP exhibited reduced proliferation, probably mediated by secreted FRP molecule. 16 genomic variations were identified, among which 4 were polymorphisms within the promoter region and exons, and the remainder were either rare variations or intronic polymorphisms. Genotyping of 4 polymorphic sites did not reveal statistically significant association with the susceptibility to RA.

CONCLUSION

FRP mRNA is overexpressed in RA synovium, the product of which exerts inhibitory activity on synovial cell growth. Although new polymorphic sites were identified, they were not associated with susceptibility to RA, suggesting that overexpression of FRP is secondarily caused by synovial environment of RA.

Serum sex steroid hormone levels and polymorphisms of CYP17 and SRD5A2: implication for prostate cancer risk

Polymorphism of the steroid hormone-related genes might affect life-long androgen exposure, thus altering a risk of prostate cancer incidence. To evaluate the effect of the polymorphisms of CYP17 and SRD5A2 on serum steroid hormone levels, the 164 male Japanese cohort were tested for serum hormone levels and the genotype of the polymorphisms of CYP17 (T-C base substitution in the promoter region) and SRD5A2 (V89L). The linear trends across the CYP17 genotypes in serum-free testosterone and androstenedione levels were found, suggesting the importance of the polymorphism of CYP17 in determining the circulating androgen levels.

Comparative study of the haplotype structure and linkage disequilibrium of chromosome 1p36.2 region in the Korean and Japanese populations

The patterns of linkage disequilibrium (LD) in the human genome provide important information for disease gene mapping. LDs may vary depending on chromosomal regions and populations. We have compared LD and haplotypes defined by SNPs in the chromosome 1p36.2 region of the Korean and Japanese populations. Fifty-eight SNPs in about 418 kb ranging from tumor necrosis factor receptor 2 (TNFR2:TNFRSF1B) to procollagen-lysine, 2-oxoglutarate 5-dioxygenase (PLOD) gene were examined in 96 healthy Koreans and Japanese each by direct sequencing and fluorescence correlation spectroscopy combined with the PCR-sequence specific primer method (PCR-SSP-FCS), respectively. Upon pair-wise LD analysis, a total of 25 and 16 out of 58 SNPs greater than MAF 10% were included in LD blocks, encompassing almost 81 kb and 55 kb in total, in Koreans and Japanese, respectively. Both similarities and differences were observed in LD strength and haplotype frequencies between the populations. Considerable similarities were observed in the telomeric region where a long-range block of approximately 80 kb including three genes was found to have strong LDs in both Koreans and Japanese. Significant difference in LD strength was present near the TNFR2 region between the Japanese and Korean populations.

Association of CYP17 with HLA-B27-negative seronegative spondyloarthropathy in Japanese males

Susceptibility genes for seronegative spondyloarthropathy (SNSA) other than HLA-B27 remain unclarified. Sex hormones are implicated in the pathogenesis of SNSA. Cytochrome P450c17a (CYP17) is a key regulator of androgen biosynthesis, and a single nucleotide polymorphism (SNP) in the 5'-untranslated region of the CYP17 gene (CYP17), -34C > T, is associated with variety of diseases. We have investigated the association between the CYP17 SNP and SNSA in Japanese males. Genomic DNA was extracted from 149 Japanese male SNSA patients and 380 controls. The CYP17 SNP was genotyped using polymerase chain reaction-restriction fragment length polymorphism analysis. Allelic and genotypic frequencies of the SNP were compared between SNSA patients and controls, and within SNSA patients. We also computed haplotype frequencies using an expectation-maximization algorithm, analyzed the difference between SNSA and control groups, and examined the potential association of other known SNPs in the CYP17 gene. The frequency of the -34T allele was significantly increased in HLA-B27-negative SNSA, but not in total or HLA-B27-positive SNSA when compared to controls. The T allele was more prevalent in HLA-B27-negative SNSA than in HLA-B27-positive SNSA, and the T/T genotype was over-represented in HLA-B27-negative SNSA. Haplotype analysis did not demonstrate more significant association. The CYP17 SNP is associated with SNSA in HLA-B27-negative Japanese males.

CD72 polymorphisms associated with alternative splicing modify susceptibility to human systemic lupus erythematosus through epistatic interaction with FCGR2B

We previously reported association of FCGR2B-Ile232Thr with systemic lupus erythematosus (SLE) in three Asian populations. Because polymorphism of CD72, another inhibitory receptor of B cells, was associated with murine SLE, we identified human CD72 polymorphisms, tested their association with SLE and examined genetic interaction with FCGR2B in the Japanese (160 SLE, 277 controls), Thais (87 SLE, 187 controls) and Caucasians (94 families containing SLE members). Four polymorphisms and six rare variations were detected. The former constituted two major haplotypes that contained one or two repeats of 13 nucleotides in intron 8 (designated as *1 and *2, respectively). Although association with susceptibility to SLE was not detected, the *1 allele was significantly associated with nephritis among the Japanese patients (P=0.024). RT-PCR identified a novel alternatively spliced (AS) transcript that was expressed at the protein level in COS-7 transfectants. The ratio of AS/common isoforms was strikingly increased in individuals with *2/*2 genotype when compared with *1/*1 (P=0.000038) or *1/*2 (P=0.0085) genotypes. Using the two Asian cohorts, significant association of FCGR2B-232Thr/Thr with SLE was observed only in the presence of CD72-*1/*1 genotype (OR 4.63, 95% CI 1.47-14.6, P=0.009 versus FCGR2B-232Ile/Ile plus CD72-*2/*2). Minigene assays demonstrated that the 13-nucleotide repeat and 4 bp deletion within the same haplotype of intron 8 could regulate alternative splicing. The AS isoform lacks exon 8, and is deduced to contain 49 amino acid changes in the membrane-distal portion of the extracellular domain, where considerable amino acid changes are known in CD72(c) allele associated with murine SLE. These results indicated that the presence of CD72-*2 allele decreases risk for human SLE conferred by FCGR2B-232Thr, possibly by increasing the AS isoform of CD72.

Immunogenetic features in 120 Japanese patients with idiopathic inflammatory myopathy

OBJECTIVE

To examine the role of HLA-DRB1 and tumor necrosis factor (TNF) promoter genotypes in the development and the autoantibody profiles of idiopathic inflammatory myopathy (IIM) in Japanese patients.

METHODS

HLA-DRB1 and TNF promoter genotypes were determined, and serum antinuclear autoantibodies were identified in 120 adult Japanese patients with IIM [72 with dermatomyositis (DM), 30 with polymyositis (PM), 18 with myositis overlapping with other collagen vascular diseases], as well as in 265 controls.

RESULTS

Forty-two patients (35%) were positive for myositis-specific autoantibodies (MSA), including 37 (31%) for anti-aminoacyl-tRNA synthetase (ARS) autoantibodies. Allele carrier frequency of HLA-DRB1*0803 was increased in the patients with IIM [p = 0.02, corrected p (pc) NS, 23% vs 14%, odds ratio (OR) = 1.9 (95% confidence interval, CI = 1.1-3.2)], with PM [p = 0.006, pc NS, 33%, OR 3.1 (95% CI 1.3-7.1)], and with anti-ARS autoantibodies [27%, p = 0.04, OR 2.3 (95% CI 1.0-5.1)] compared with controls. DRB1*0405 was increased in patients with anti-ARS autoantibodies compared with controls [41% vs 25%, p = 0.04, pc NS, OR 2.1 (95% CI 1.0-4.3)]. TNF promoter genotype was associated with the presence of interstitial lung disease (ILD). The carriage of a TNF-a haplotype formed by -1031C, -863A, and -857C was increased in the patients with ILD versus those without ILD [33% vs 18%, p = 0.05, pc NS, OR 2.3 (95% CI 0.94-5.5)].

CONCLUSION

HLA-DRB1 alleles were associated with development of IIM and MSA in a Japanese population.

Molecular genetic analyses of human NKG2C (KLRC2) gene deletion

Human NKG2A, NKG2C and NKG2E genes are located on 12p13 in the NK gene complex. We recently identified deletion of NKG2C in a Japanese population. This study was performed to identify the breakpoint, and to examine the association of NKG2C deletion with susceptibility to rheumatoid arthritis and systemic lupus erythematosus. The location of the breakpoint was determined to be 1.5-1.8 kb telomeric from the 3' end of NKG2A by comparing sequences of the intergenic segments upstream and downstream of the NKG2C gene in the common haplotype with the intergenic sequence between NKG2A and NKG2E in the deletion haplotype. Based on this information, a genotyping system was developed. The frequency of NKG2C deletion haplotype was 20.2% in Japanese and 20.0% in Dutch populations. The frequency of homozygous deletion was 4.1% in Japanese and 3.8% in Dutch. Evidence for an association with rheumatic diseases was not detected. These results indicated that NKG2C deletion is commonly present in Japanese and Dutch, suggesting that NKG2C is not essential for survival and reproduction, and is not associated with rheumatic diseases.

The human histocompatibility leukocyte antigen (HLA) haplotype is associated with the onset of postherpetic neuralgia after herpes zoster

In some herpes zoster patients, pain persists for more than 3 months or more after healing of vesicular eruptions; this condition is termed postherpetic neuralgia (PHN). We have recently reported the association of the human histocompatibility leukocyte antigens (HLA) haplotype, HLA-A*3303-B*4403-DRB1*1302 with PHN patients; however, it has not been determined whether the haplotype is also associated with herpes zoster that did not develop subsequent PHN. To distinguish whether the haplotype is associated with herpes zoster or the development of PHN, we examined if herpes zoster patients without subsequently PHN are also associated with the HLA haplotype or not. Herpes zoster patients were followed up for more than 6 months, and HLA alleles and haplotypes were compared among the PHN patients (n = 52) the herpes zoster patients who did not develop PHN (n = 42) and healthy controls (n = 125). The frequencies of the risk haplotype in the PHN patients, in the healthy controls and in the herpes zoster patients without subsequent PHN were 16.3, 5.2 and 4.8%, respectively. While the frequency of the risk haplotype was significantly higher in the PHN patients than in the healthy controls (P = 0.0006) no difference was observed between the herpes zoster patients without subsequent PHN and the healthy controls. No significant association was found between the duration of symptoms or the site of herpes zoster and the HLA alleles and the haplotype. These results suggest that the HLA-A*3303-B*4403-DRB1*1302 haplotype plays an important role in the development of PHN after herpes zoster, but not in the onset of herpes zoster.

Changes in plasma ghrelin and growth hormone concentrations in mature Holstein cows and three-month-old calves1

We measured changes in plasma ghrelin and GH concentrations in mature Holstein cows and 3-mo-old female Holstein calves fed at scheduled times. Our objective was to determine the characteristics of ghrelin secretion in dairy cattle and its influence on GH. Animals were fed at 0800 and 1600 for 2 wk before and during experiments. Plasma was sampled for 24 h at 2-h intervals in Exp. 1. In mature cows, plasma ghrelin concentrations decreased (P < 0.01) just after 0800 but not at the 1600 feeding. Ghrelin concentrations were lower (P < 0.01) in calves than in mature cows and they did not decrease after feeding in calves. The temporal relationship between ghrelin and GH remained unclear. In Exp. 2, plasma was sampled 2 h before and after both morning and evening feedings at 20-min intervals. Plasma ghrelin concentrations decreased (P < 0.05) 40 min after 0800 feeding and 60 min after 1600 feeding in mature cows. These results indicate that in mature cows, plasma ghrelin concentration decreased after feeding, but this decrease was not evident in 3-mo-old calves. Further studies are required to define the relationship between plasma ghrelin and GH concentrations.

BAFF/BLyS can potentiate B-cell selection with the B-cell coreceptor complex

The tumor necrosis factor (TNF)–like ligand BAFF/BLyS (B-cell activating factor of the TNF family/B-lymphocyte stimulator) is a potent B-cell survival factor, yet its functional relationship with other B-cell surface molecules such as CD19 and CD40 is poorly understood. We found that follicular dendritic cells (FDCs) in human lymph nodes expressed BAFF abundantly. BAFF up-regulated a B cell–specific transcription factor Pax5/BSAP (Pax5/B cell–specific activator protein) activity and its target CD19, a major component of the B-cell coreceptor complex, and synergistically enhanced CD19 phosphorylation by B-cell antigen receptor (BCR). BAFF further enhanced B-cell proliferation, immunoglobulin G (IgG) production, and reactivity to CD154 by BCR/CD19 coligation and interleukin-15 (IL-15). Our results suggest that BAFF may play an important role in FDC–B-cell interactions through the B-cell coreceptor complex and a possibly sequential link between the T cell–independent and –dependent B-cell responses in the germinal centers.

Association of Fcgamma receptor IIb polymorphism with susceptibility to systemic lupus erythematosus in Chinese: a common susceptibility gene in the Asian populations

The association of Fcgamma receptor (FcgammaR) polymorphisms with systemic lupus erythematosus (SLE) has been demonstrated in various populations; however, the results have been inconsistent. We recently identified a single-nucleotide polymorphism encoding a non-synonymous substitution, Ile232Thr (I232T), of FCGR2B and its association with SLE in Japanese and in Thais. Multiple functional FcgammaR genes with polymorphisms (FCGR2A, FCGR2B, FCGR3A, and FCGR3B) cluster in 1q23, and some of them are in linkage disequilibrium (LD). To differentiate contributions from multiple-linked loci, comparison of different populations may provide useful information. In this study, we analyzed the above four FCGR polymorphisms of the Chinese patients and controls for the association with SLE. FCGR2A-H131R, FCGR2B-I232T, FCGR3A-F176V, and FCGR3B genotypes were determined in 167 Chinese patients with SLE and 129 healthy controls. Association was examined using case-control analysis. Allele frequencies of FCGR2B-232T and FCGR3A-176F were significantly increased in SLE [odds ratio (OR) = 1.67 and OR = 1.41, respectively]. Interestingly, while these alleles had a tendency of positive LD in the controls, FCGR2B-232T was in positive association with FCGR3A-176V in SLE, suggesting that these two alleles were associated with SLE in an independent manner. Comparison between SLE with and without nephritis indicated significant association of FCGR2B-232T with nephritis (OR = 2.65). When the present results were combined with our previous data on the Japanese and the Thais using meta-analytic methods, highly significant and independent association was observed for FCGR2B and FCGR3A genotypes. These results strongly suggested that FCGR2B is a common susceptibility factor to SLE in the Asians.

Vaccination of recurrent glioma patients with tumour lysate-pulsed dendritic cells elicits immune responses: results of a clinical phase I/II trial

In this Phase I/II trial, the patient's peripheral blood dendritic cells were pulsed with an autologous tumour lysate of the glioma. Seven patients with glioblastoma and three patients with anaplastic glioma, ranging in age from 20 to 69 years, participated in this study. The mean numbers of vaccinations of tumour lysate-pulsed dendritic cells were 3.7 times intradermally close to a cervical lymph node, and 3.2 times intratumorally via an Ommaya reservoir. The percentage of CD56-positive cells in the peripheral blood lymphocytes increased after immunisation. There were two minor responses and four no-change cases evaluated by radiological findings. Dendritic cell vaccination elicited T-cell-mediated antitumour activity, as evaluated by the ELISPOT assay after vaccination in two of five tested patients. Three patients showed delayed-type hypersensitivity reactivity to the autologous tumour lysate, two of these had a minor clinical response, and two had an increased ELISPOT result. Intratumoral CD4+ and CD8+ T-cell infiltration was detected in two patients who underwent reoperation after vaccination. This study demonstrated the safety and antitumour effects of autologous tumour lysate-pulsed dendritic cell therapy for patients with malignant glioma.

Rectosigmoidal bladder utilizing an intussuscepted ileal segment: a surgical technique for urinary diversion

A novel technique of urinary diversion was designed by interposition of an intussuscepted ileal segment between the ureters and the rectosigmoidal pouch, thus preventing ureteral reflux as well as stenosis at the uretero-enteric anastomosis, possible occurrence of urocolonic carcinoma, and frequent evacuation or incontinence. Since all the procedures were limited to the lower abdominal cavity, the surgical invasiveness was compatible with that of an ileal conduit. Our early experience in 15 patients showed that this technique can be considered for those in whom the urethra is not available.

Total cystoprostatectomy in the treatment of locally advanced prostate carcinoma

OBJECTIVE

Locally advanced prostate carcinoma frequently causes lower urinary tract symptoms and is a clinical challenge when radiation and/or hormone therapy fail. We investigated whether cystoprostatectomy with urinary diversion benefits patients with locally advanced prostate carcinoma in terms of quality of life and prognostic outcome.

PATIENTS AND METHODS

Between 1989 and 2001, we performed 15 cystoprostatectomies for stage C-D1 prostate carcinoma with bladder neck involvement. Of these patients, 5 underwent ileal conduit, 8 rectal bladder, 1 Koch pouch, and 1 ureterocutaneostomy. All the patients received neoadjuvant and/or adjuvant hormonal therapy. In the same period, 28 patients underwent retropubic prostatectomies and 15 patients received hormone therapy alone for stage C-Dl disease. These patients were included as references.

RESULTS

Lower urinary tract symptoms caused by bladder involvement were controlled well until the end of follow-up for all the patients in the cystoprostatectomy group. There was no statistically significant difference in QOL score assessed with the EORTC QLQ-C30 questionnaire between the prostatectomy group and the cystoprostatectomy group, while that in the hormone therapy group was lower than those in the surgery groups. There was no statistically significant difference in 5-year PSA-relapse-free survival among cystoprostatectomy, prostatectomy, and hormone therapy groups. Patients in the hormone therapy group died earlier than those in the prostatectomy group (p = 0.02), while those in the cystoprostatectomy group did not.

CONCLUSION

These results suggest that total cystoprostatectomy with urinary diversion is a valid option, in terms of disease control and QOL, for prostate cancer patients whose tumor is infiltrating into the bladder.

Role of the Fcgamma receptor IIA polymorphism in the antiphospholipid syndrome: an international meta-analysis

OBJECTIVE

To assess the impact of the FcgammaRIIA-R/H131 polymorphism on the risk for antiphospholipid syndrome (APS), both primary and secondary to systemic lupus erythematosus (SLE).

METHODS

This international meta-analysis combined data from 9 research teams. FcgammaRIIA-R/H131 genotypes were determined in 481 APS cases (206 with primary APS), 1,420 SLE controls, and 1,655 disease-free controls. Data were combined using fixed-effects and random-effects models.

RESULTS

Compared with disease-free controls, the RR genotype was enriched in the entire group of APS cases (odds ratio [OR] 1.65, 95% confidence interval [95% CI] 1.28-2.14); this was driven mostly by patients with secondary APS (OR 1.95, 95% CI 1.45-2.63). The excess of RR homozygotes but not heterozygotes among APS patients suggested a recessive mode of inheritance, rather than the additive model seen for SLE susceptibility, where RR conferred greatest risk, and RH intermediate risk, for SLE. This probably reflected the additional influence of another opposing genetic effect of HH homozygosity on APS predisposition (OR 0.72 for RH versus HH, 95% CI 0.55-0.96). Among SLE patients, those with APS were more frequently HH homozygotes than heterozygotes (OR 0.56 for RH versus HH, 95% CI 0.39-0.81). HH homozygosity also tended to predominate in primary APS compared with secondary APS (OR 0.50 for RR versus HH, 95% CI 0.25-0.99 by fixed-effects model). There was no significant between-study heterogeneity for any of these effects.

CONCLUSION

The FcgammaRIIA-R/H131 polymorphism is an important determinant of predisposition to APS, with different influences on SLE and APS susceptibility per se.

Genetic background of Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis: association of HLA-DRB1*0901 with microscopic polyangiitis

OBJECTIVE

To examine association of 8 candidate genes with susceptibility to antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in Japanese patients. Little is known on the genetic background of AAV in Japanese patients mainly because of the difficulty in collecting a sufficient number of samples for the genetics study.

METHODS

Sixty-nine patients, including 50 with microscopic polyangiitis (MPA), were recruited in a multicenter study. Among them, 64 patients were positive for myeloperoxidase (MPO)-ANCA. Associations of HLA-DRB1, tumor necrosis factor-alpha promoter (TNF), TNF receptor 2 (TNFR2), Fcgamma receptor IIa (FCGR2A), IIb (FCGR2B), IIIa (FCGR3A), IIIb (FCGR3B), and CTLA-4 (CTLA4) polymorphisms were examined in a case-control analysis.

RESULTS

A significant association of HLA-DRB1*0901 with MPA (p = 0.0037, OR 2.44, 95% CI 1.33-4.46), as well as with MPO-ANCA positivity (p = 0.0014, OR 2.44, 95% CI 1.41-4.22), was detected. There was no difference in the TNF promoter haplotype frequencies between patients with MPA and controls, excluding the possibility that the association of DRB1*0901 was secondarily caused by linkage disequilibrium with TNF. No association was observed for TNFR2, FCGR, or CTLA4 with MPA, nor with the presence of MPO-ANCA, although the combined genotype FCGR2A-131H/H and 3A-176F/F was increased in patients with MPA (p = 0.025).

CONCLUSION

There was an association of HLA-DRB1*0901 with MPA and MPO-ANCA positive vasculitis in Japanese patients.

Association of Fcgamma receptor IIb and IIIb polymorphisms with susceptibility to systemic lupus erythematosus in Thais

We recently reported association of a newly identified polymorphism of Fcgamma receptor (FcgammaR) IIb, I232T, with systemic lupus erythematosus (SLE) in Japanese. To date, information on FcgammaR genotypes and their association with SLE is limited in South-east Asian populations. To gain further insight into the role of FcgammaR polymorphisms in the genetic predisposition of SLE, association of FcgammaRIIa-H131R, IIb-I232T, IIIa-F176V and IIIb-NA1/NA2 (HNA-1a/1b) polymorphisms with SLE was analyzed in the Thai population, using case-control association analysis. FcgammaRIIb-232T/T and IIIb-NA2/NA2 genotypes were associated with SLE with the odds ratio of 2.55. Genotype relative risk analysis revealed significant association of IIb-232T/T and IIIb-NA2/NA2, and a tendency of association of the IIIa-176F/F genotype. Moreover, carriers of FcgammaRIIa-131R were significantly increased in patients with lupus nephritis. Significant linkage disequilibrium was present among FcgammaRIIb, IIIa and IIIb, and two-locus analyses suggested that the tendency of association of FcgammaRIIIa could derive from linkage disequilibrium with IIb and IIIb. These results provided evidence that FcgammaR polymorphisms may be an important predisposing factor also in Thais in a complex manner.

Variations of human killer cell lectin-like receptors: common occurrence of NKG2-C deletion in the general population

CD94 and NKG2 are members of the NK cell receptor families, and are encoded in the natural killer gene complex (NKC) on human chromosome 12p12-13, one of the candidate chromosomal regions for rheumatic diseases. To examine a possible association between variations in CD94 and NKG2 genes and genetic susceptibility to rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), we carried out a systematic polymorphism screening of NKG2-A (KLRC1), NKG2-C (KLRC2) and CD94 (KLRD1) genes on a population basis. In NKG2-A, previously considered to be highly conserved, 10 polymorphisms in the noncoding region and introns, as well as one rare variation leading to an amino acid substitution within the transmembrane region, c.238T>A (Cys80Ser), were detected. In NKG2-C, in addition to the previously described two nonsynonymous substitutions, c.5G>A (Ser2Asn) and c.305C>T (Ser102Phe), two polymorphisms were newly detected in the noncoding region. In CD94, only one single nucleotide substitution was identified in the 5' untranslated region. When the patients and healthy individuals were genotyped for these variations, no significant association was observed. However, although statistically not significant, NKG2-A c.238T>A (Cys80Ser) was observed in three patients with RA, but in none of the healthy individuals and the patients with SLE. Unexpectedly, in the process of polymorphism screening, we identified homozygous deletion of NKG2-C in approximately 4.3% of healthy donors; under the assumption of Hardy-Weinberg equilibrium, the allele frequency of NKG2-C deletion was estimated to be 20.7%. These results demonstrated that, although human NKG2-A, -C and CD94 are generally conserved with respect to amino acid sequences, NKG2-A is polymorphic in the noncoding region, and that the number of genes encoded in the human NKC is variable among individuals, as previously shown for the leukocyte receptor complex (LRC), HLA and Fcgamma receptor (FCGR) regions.

Variations in the human Th2-specific chemokine TARC gene

Th2-specific chemokine thymus and activation-regulated chemokine (TARC)/CC chemokine ligand (CCL)17 is highly implicated in the pathogenesis of Th-2-dominated allergic diseases such as bronchial asthma (BA) and atopic dermatitis (AD). We performed polymorphism screening of the coding and promoter regions of the TARC gene. We found two rare variations in the coding region of exon 3 (2134C>T and 2037G>A) and a single nucleotide polymorphism (SNP) in the 5'-flanking region (-431C>T). Individuals carrying the 431T allele showed significantly increased serum levels of TARC compared with those not carrying the 431T allele, suggesting that this SNP has functional significance. However, when the genotypes at the SNP site were determined for 158 healthy individuals, 105 patients with BA and 148 patients with AD, we observed no significant association of the SNP with susceptibility to BA or AD.