Diversity of human leukocyte antigen-B27 alleles in Han population of Hunan province, southern China

This study was to investigate the frequency of HLA-B27 and its subtypes in the Han population of Hunan province, southern China. One hundred and sixty-nine healthy unrelated donors were tested for HLA-B27 by polymerase chain reaction-sequence-specific primer (PCR-SSP). One hundred and twenty-eight B27-positive spondyloarthropathy patients and 18 B27-positive healthy controls were subtyped using the high-resolution PCR-SSP. The phenotype frequency of human leukocyte antigen (HLA)-B27 was found to be 2.36% in healthy population. Five B27 alleles were identified: B*2704, B*2705, B*2706, B*2707, and B*2724. No significant difference was found in the distribution of HLA-B27 subtypes between the patients and controls studied. Notably, B*2724 was observed in a juvenile patient with ankylosing spondylitis. This subtype has not been previously reported in Chinese ankylosing spondylitis (AS) patients and other ethnic groups.     

HLA B27 polymorphism in Western India

We have characterized HLA B27 alleles in a sample population of Maharastra, Western Indians (n = 51), with the aim to investigate the different subtypes present among this population. The study was carried out using polymerase chain reaction with sequence-specific primers (PCR-SSP) and reverse line strip (RLS) techniques. Significant new findings have arisen from this study: B*2704, B*2705, B*2707, B*2708 and B*2714 alleles were found to be present, and two novel B27 alleles, B*2708 and B*2714, were found in this Indian population. In addition, B*2714 was observed in a patient with ankylosing spondylitis. This association has not been previously reported in ethnic groups from India.     

High serum vascular endothelial growth factor correlates with disease activity of spondylarthropathies

Angiogenesis is involved in chronic inflammatory joint diseases such as rheumatoid arthritis (RA). Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis. The spondylarthropathies (SpA) are characterized by enthesitis and synovitis, in which blood vessels participate. The objective of this study was to investigate serum VEGF levels and their potential associations with disease activity markers for SpA. Sera were collected from 105 patients with SpA (72 with ankylosing spondylitis (AS), four with psoriatic arthritis (PsA), six with reactive arthritis (ReA), eight with enteropathic arthropathy and 15 with undifferentiated SpA), 50 patients with rheumatoid arthritis (RA) and 64 healthy controls. Disease activity in SpA patients was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and laboratory parameters of inflammation [erythrocyte sedimentation rate (ESR) and C-reactive protein level (CRP)]. Serum VEGF levels were significantly higher in SpA patients (316.4 +/- 215.6 pg/ml) and RA patients (405.2 +/- 366.5) than in controls (217.3 +/- 145.2) (P = 0.003). In SpA patients, serum VEGF levels correlated with disease activity indices (BASDAI: r = 0.22, P = 0.04; ESR: r = 0.3, P = 0.003; and CRP: r = 0.23, P = 0.02). Serum VEGF levels were not associated with presence of extra-articular manifestations or syndesmophytes or with the grade of sacroiliitis. These results suggest that VEGF and therefore angiogenesis may play a role in SpA pathogenesis and may serve as a disease activity marker in SpAs.     

Tumor necrosis factor-alpha promoter polymorphisms in Mexican patients with spondyloarthritis

To evaluate the role of tumor necrosis factor-alpha (TNF-alpha) gene as susceptibility marker for spondyloarthritis (SpA), two polymorphisms (-238 and -308 positions) were analyzed in 229 patients with SpA (113 with ankylosing spondylitis [AS], 92 with undifferentiated SpA [U-SpA], 24 with reactive arthritis), and 169 ethnically matched healthy control subjects. The HLA-B alleles were detected by PCR-SSP technique and the TNF-alpha polymorphism by PCR-RFLP. In comparison with healthy control subjects, the frequencies of TNF-238 in SpA were similar. In contrast, the analysis of -308 polymorphism showed increased frequencies of the T2(A) allele in the whole SpA group (p < 0.05, pC = NS, OR = 1.83) as well as the T2(A) allele (pC < 0.05, OR = 2.4) and T1T2(AG) genotype (p < 0.05, pC = NS, OR = 2.25) in U-SpA patients. Comparison of B27-negative patients and healthy control subjects yielded similar results. There was no significant correlation between TNF genotypes and clinical data. The present study demonstrates that TNF-alpha -308 polymorphism appears to be associated with the genetic susceptibility U-SpA. The association seems independent of the susceptibility conferred by the HLA-B27 in this group of patients.     

New insights regarding HLA-B27 diversity in the Asian population

A polymerase chain reaction-sequence-specific primer (PCR-SSP) method which distinguishes all B27 alleles described at present (B*2701-23) has been developed. The distribution of B27 alleles was characterised in six different Asian populations. HLA-B*2705, 02, 04, 07, 22 (formerly B*2706) subtypes found in Asian populations differ in their ethnic distribution, which may be the result of different genetic and geographic origins. Furthermore, two novel B27 alleles were found in this study. B*2714 was identified in two Siberians, one of whom was a patient with ankylosing spondylitis. B*2715 was found in two patients with ankylosing spondylitis in Thais. These associations have not previously been reported in either ethnic group.     

Deoxyribonuclease activity of polyclonal IgGs: a putative serological marker in patients with spondyloarthritides

Antibodies executing catalytic activity are referred to as antibody enzymes or short “abzymes” and may have diagnostic relevance. Abzymes with deoxyribonuclease (DNase) activity have been demonstrated in patients with autoimmune and infectious diseases. Despite several reports on the occurrence of DNase abzymes in systemic autoimmune rheumatic diseases, conclusive data about DNase activity of antibodies in patients with spondyloarthritides (SpAs) are lacking. In recent cross-sectional studies evaluating levels of IgG DNase activity in patients with psoriatic arthritis (PsA), reactive arthritis (ReA), and ankylosing spondylitis (AS), DNase activity of IgG has been assessed by the rivanol clot method and confirmed by agarose gel electrophoresis. Remarkably, levels of IgG DNase activity were significantly higher in sera of SpA patients than those in control subjects. In patients with PsA, ReA, and AS, a positive correlation of DNase IgG activity with synovitis, disease activity, and stage of spondylitis was observed, respectively. Given the involvement of autoimmune reactions in cytolysis and connective tissue degradation in PsA, ReA, and to a lesser extent in AS, abzymes might have an impact on the pathophysiology of SpAs. Detection of IgG DNase activity in patients suffering from SpA represents an exciting new research field and may assist in the differential diagnosis of SpA.     

HLA and Juvenile Chronic Polyarthritis

HLA antigen have been identified in patients with juvenile chronic polyarthritis (J.C.P.) (n = 35). In J.C.P. the incidence of antigen B27 (57%) was found to be higher than in a normal population (n = 1,000). On recent evaluation of the clinical status, serology and x-rays, the patients with juvenile chronic polyarthritis who has been followed up many years, could be subdivided into four groups: Group 1: J.C.P. evolving to ankylosing spondylitis (n = 3); Group 2: J.C.P. with sacroiliitis (n = 17); Group 3: J.C.P. without sacroiliitis (n = 9); Group 4: juvenile rheumatoid arthritis characterised by a positive serology (n = 6). Groups 1 and 2 were characterized by a high incidence of antigen B27 (19/20). Only one subject of groups 3 and 4 had antigen B27. Sex distribution in groups 1 and 2 was found to be similar to that found in ankylosing spondylitis in adults and sex distribution in groups 3 and 4 was found to be similar to that found in rheumatoid arthritis in adults. It is concluded that if B27 positive develop juvenile chronic polyarthritis they have a high risk of developing sacroiliitis and acute uveitis. The authors propose to give the name Still's disease to the total group of children presenting initial symptoms corresponding to the criteria of Ansell & Bywaters (1959). Follow-up of the cases permitted their further classification as juvenile ankylosing spondylitis, as juvenile chronic polyarthritis with or without sacroiliitis or as juvenile rheumatoid arthritis.     

The MICA-A4 triplet repeats polymorphism in the transmembrane region confers additional risk for development of psoriatic arthritis in the Croatian population.

The aim of this study was to investigate possible differences in the frequencies of alleles at the HLA loci and at microsatellite loci within the HLA region among patients suffering from psoriatic arthritis (PsA) and healthy controls. Fifty-eight Croatian PsA patients (28 male and 30 female) and 157 healthy unrelated controls were typed for HLA alleles (A, B, Cw and DRB1) by the polymerase chain reaction-sequence-specific primers (PCR-SSP) method, while microsatellite alleles (D6S265, D6S273, MHC class I chain-related gene (MICA) and MIB) were analysed by electrophoresis in an ALFexpress sequencer (Pharmacia Biotech, Uppsala, Sweden). The findings from this study were: (1) the frequencies of B*39 and B*57 were significantly increased in PsA patients; (2) differences in the frequencies of B*13 and B*27 were not statistically significant after correction; (3) the B*0702, B*18, and B*38 alleles were decreased in patients only before correction; (4) none of the alleles at other HLA loci tested were associated with PsA in Croatia; (5) polymorphism at D6S265, D6S273, and MIB microsatellites in patients did not show any statistically significant differences when compared to controls; (6) the increase in the MICA-A4 allele frequency in PsA patients was independent of the B*39 and B*57 alleles.     

HLA-B27 in the Greek Cypriot population: distribution of subtypes in patients with ankylosing spondylitis and other HLA-B27-related diseases. The possible protective role of B*2707

The major purpose of the present study was to investigate the frequency of human leukocyte antigen (HLA)-B27 alleles in healthy controls and in patients with ankylosing spondylitis (AS) and other HLA-B27–related diseases in the Greek Cypriot population. We selected 102 HLA-B27–positive individuals (60 controls and 42 patients). Typing of the HLA-B27 alleles was performed by polymerase chain reaction amplification with sequence-specific primers. Only two alleles were detected in the patient group: B*2702 (n = 31, 73.8%) and B*2705 (n = 11, 26.2%). The HLA-B*2707 allele was detected (n = 10, 16.7%) only in the healthy controls in addition to the B*2702 (n = 31, 51.7%) and B*2705 (n = 19, 31.7%) alleles. Our results show a restricted number of HLA-B27 subtypes associated with AS and other B27-related diseases and an elevated frequency of the B*2702 allele in the AS patients. The allele B*2707 seems to have a protective role in the population studied because it was found only in the healthy controls.     

The MICA‐A4 triplet repeats polymorphism in the transmembrane region confers additional risk for development of psoriatic arthritis in the Croatian population

The aim of this study was to investigate possible differences in the frequencies of alleles at the HLA loci and at microsatellite loci within the HLA region among patients suffering from psoriatic arthritis (PsA) and healthy controls. Fifty‐eight Croatian PsA patients (28 male and 30 female) and 157 healthy unrelated controls were typed for HLA alleles (A, B, Cw and DRB1) by the polymerase chain reaction–sequence‐specific primers (PCR‐SSP) method, while microsatellite alleles (D6S265, D6S273, MHC class I chain‐related gene (MICA) and MIB) were analysed by electrophoresis in an ALFexpress sequencer (Pharmacia Biotech, Uppsala, Sweden). The findings from this study were: (1) the frequencies of B*39 and B*57 were significantly increased in PsA patients; (2) differences in the frequencies of B*13 and B*27 were not statistically significant after correction; (3) the B*0702, B*18, and B*38 alleles were decreased in patients only before correction; (4) none of the alleles at other HLA loci tested were associated with PsA in Croatia; (5) polymorphism at D6S265, D6S273, and MIB microsatellites in patients did not show any statistically significant differences when compared to controls; (6) the increase in the MICA‐A4 allele frequency in PsA patients was independent of the B*39 and B*57 alleles.     

Rheumatic manifestations in inflammatory bowel disease

Musculoskeletal symptoms (articular, periarticular and muscular involvement, osteoporosis and related fractures, and fibromyalgia) are the most common frequent extra-intestinal manifestations of inflammatory bowel disease (IBD) and affect 6–46% of patients. IBD-related arthropathy is one of a group of inflammatory arthritides known as seronegative spondyloarthropathies (SpA), which also includes idiopathic ankylosing spondylitis (AS), reactive arthritis, psoriatic arthritis, and undifferentiated SpA.The articular involvement in IBD significantly affects the patients’ quality of the life. Although magnetic resonance imaging (MRI) is still the gold standard for assessing entheseal involvement, ultrasonography (US) is a non-invasive and easily reproducible means of detecting early pathological changes in SpA patients. It can identify characteristic features of SpA such as enthesitis, bone erosions, synovitis, bursitis, and tenosynovitis and is therefore helpful for diagnostic purposes.Anti-TNF drugs should be used to treat AS patients with axial and peripheral symptoms (arthritis and enthesitis) who have persistently high levels of disease activity despite conventional treatment, and adalimumab and infliximab can also be beneficially used in patients with IBD.     

Polymorphism in MICA rather than HLA-B/C genes is associated with psoriatic arthritis in the Jewish population

The aim of this study was to examine whether the association of psoriatic arthritis (PsA) with human leukocyte antigen (HLA) class I genes is secondary to linkage disequilibrium with a nearby gene. We examined a sample of the Jewish population to investigate whether HLA-B/C and DR polymorphism is associated with susceptibility, or whether other closely related class I loci, such as the major histocompatibility complex class I chain-related gene A (MICA) and tumor necrosis factor (TNF), might play a role in disease development. Comparisons of different populations with different HLA profiles would be of value in identifying the candidate genes involved in PSA. Fifty-two patients with PsA and 73 random matched controls from a Jewish population were selected and DNA typed by polymerase chain reaction-single-strand oligonucleotide probe (PCR-SSOP) (HLA-C), PCR sequence-specific primers (PCR-SSP) (HLA-B, -DR), radioactive PCR (MICA-TM polymorphism in the transmembrane region), and PCR-RFLP (TNF). Some findings can be concluded from the study: (1) the frequency of HLA-B*5701, B*3801, B*39, B*27, Cw*0602, Cw*07, DRB1*0402, and DRB1*0701 were not found to be significantly increased in PsA; (2) no significant differences of TNFalpha promoter alleles at positions -308 and -238 were found between PsA and healthy controls; (3) the trinucleotide repeat polymorphism MICA-A9 was present at a higher frequency in PsA patients, (p(c) < 0.009, RR = 3.34, EF = 0.39); and (4) MICA-A9 polymorphism was found in linkage disequilibrium with HLA-B alleles (B*5701, B*3801) described to be associated with PsA in Caucasians. These results suggest that the MICA gene or other nearby gene(s) may be involved in the development of PsA, and it would thus appear that psoriasis vulgaris (PsV) and PsA are associated with different MHC susceptibility genes.     

Can we reduce the dosage of biologics in spondyloarthritis?

TNF blockers have revolutionized the management of spondyloarthritis (SpA). To date, four anti-TNFα agents (etanercept, infliximab, adalimumab, golimumab) have been approved for the management of ankylosing spondylitis (AS) and psoriatic arthritis (PsA). The first objective in the management of AS and PsA with TNF inhibitors is to reduce disease activity to clinical remission or low disease activity. After remission has been achieved, this state should be maintained as long as possible. However, the financial burden associated with the cost of anti-TNF agents as well as concerns about their long-term safety suggest reducing the dosage of the drug or discontinuing the therapy in the hopes of drug-free remission. The aim of this review is to examine what has, till now, been published on this topic in axial SpA, which includes AS and non-radiographic axial SpA (nr-axSpA), peripheral SpA and PsA. Discontinuation of therapy in axial SpA is not possible in the majority of patients, while on the contrary, reducing the dosage often is. In some patients with peripheral SpA and PsA it is also possible to discontinue therapy and to achieve drug-free remission.     

HLA-B27 polymorphism and worldwide susceptibility to ankylosing spondylitis

HLA-B27 is strongly associated to ankylosing spondylitis (AS) and represents a family of eleven B27 alleles (B*2701–11). Our aim was to analyze the distribution of B27 subtypes by PCR/SSOP and genomic sequencing in a large group of populations ( n =17). 711 B27-positive samples from Caucasoid, Asian, African, Amerindian and Polynesian populations were selected to ascertain transracial gene mapping of the B27 subtypes. 476 of these were AS patients, chosen to investigate the contribution of B27 alleles to AS susceptibility. Some significant new findings have arisen from this study: 1) B*2705 was the predominant subtype in circumpolar and subarctic areas. B*2702 was found to be practically restricted to Caucasian populations, showing a higher frequency in Middle-East (Jews) and North Africa (Arabs/Berbers) groups. 2) B*2703 appears associated with AS in Western Africans. This is of remarkable interest since it was suggested that B*2703 would be negatively disease-associated. 3) Although B*2706 appears negatively associated with AS in Thais, we identified two patients from northern China carrying it. This may be a reflection of a disease heterogeneity and could indicate that more than one pathogenic agent can be involved in AS. B*2709 has been recently described as negatively associated with AS in Sardinians. The molecular changes His 114Asp (B*2706) and Asp 116His (B*2709) could modify the genetic susceptibility to AS.     

Rapid detection of all HLA-B*27 alleles (B*2701-B*2725) by group-specific polymerase chain reaction

Human leucocyte antigen-B*27 is strongly associated with a number of rheumatic diseases, including ankylosing spondylitis and reactive arthritis. Targeted detection of the B*27 group by molecular methods is hampered by the extreme heterogeneity of the serological B*27 group. Here, we describe a simple, rapid sequence-specific primer-based method for detection of all 28 B*27 alleles defined to date. The method involves an initial screening with two sequence-specific polymerase chain reactions (PCRs), which has to be followed by two additional PCR amplifications in samples carrying a few rare subtypes of B*27, B*4202 or B*7301. The described protocol should be useful for laboratories involved in diagnostics and research of rheumatoid diseases.     

Differential major histocompatibility complex class I chain-related A allele associations with skin and joint manifestations of psoriatic disease

About 30% of patients with psoriasis have psoriatic arthritis (PsA), an inflammatory arthritis that can affect both axial and peripheral joints. Major histocompatibility complex class I chain-related A (MICA) alleles have previously been shown to be associated with PsA; however it is unclear whether there is a differential association of MICA alleles with skin and joint manifestations of PsA. Here, we describe a case-control study that aims to validate previously reported MICA allele associations with PsA and determine whether MICA alleles differentiate patients with PsA from those with psoriasis without PsA. Two hundred forty-nine unrelated Caucasian PsA patients, 243 psoriasis patients without arthritis, and 248 healthy controls were genotyped for 55 MICA alleles using PCR-SSP, and for human leucocyte antigen (HLA)-B and HLA-C alleles by PCR-SSO reverse line blot. Allele frequencies were calculated and logistic regressions were performed, adjusting for HLA-B and HLA-C alleles previously shown to be associated with psoriasis and/or PsA. Several MICA alleles were associated with psoriatic disease, PsA, and psoriasis compared with controls, and PsA compared with psoriasis in univariate analyses. Haplotype analysis showed evidence of strong linkage disequilibrium (LD) between PsA and psoriasis risk alleles of HLA-C, HLA-B, and MICA. After adjusting for significant HLA-B and HLA-C alleles in multivariate analyses, MICA*016 remained significantly associated with psoriasis [odds ratio (OR) = 5.5, P = 0.008]. MICA*00801 homozygosity was associated with susceptibility to PsA when compared with patients with psoriasis alone (OR = 2.26, P = 0.009). We conclude that most MICA allele associations with psoriasis and PsA are dependent on LD with HLA-B and HLA-C risk alleles. Independent of HLA, only MICA*016 influences the risk of developing psoriasis without arthritis, and homozygosity for MICA*00801 increases the risk of developing PsA in patients with psoriasis.     

Higher prevalence of peripheral arthritis among ankylosing spondylitis patients

This study was performed to define the clinical spectrum and disease manifestations of ankylosing spondylitis (AS) in a referral hospital setting. We identified the differences in clinical manifestations according to the sex, the age at onset, the presence of peripheral arthritis and the presence of HLA B27. A total 412 patients (357 males, 55 females) were recruited. Eighty-seven percent were men and 155 out of 412 patients (35%) were juvenile-onset. HLA B27 was detected in 385 patients (93%). Peripheral joint involvement was noted in 287 of total AS cases (juvenile- onset ankylosing spondylitis (JOAS), 82%; adult-onset ankylosing spondylitis (AOAS), 61%), and was more common than those reported in other studies. A greater portion of patients with JOAS had peripheral arthritis and peripheral enthesitis than the patients with AOAS. The patients with peripheral arthritis showed a younger age at onset and an increased tendency of having enthesitis and trauma history. The natural history of Korean AS appears largely similar to those seen in Europe and North America, except a few differences. JOAS was quite common and AS was about nine times more common in men than in women. In addition, the HLA B27 antigen frequency was 93%, which is higher than those reported in other studies.     

HLA-B27 PCR辅助诊断幼年强直性脊椎炎

目的：辅助诊断幼年强直性脊椎炎。方法：用ＰＣＲ技术对２４例临床表现为类风湿关节炎少关节型患儿的ＤＮＡ进行ＨＬＡ－Ｂ２７基因分析。结果：２４份标本中７例ＰＣＲ检测Ｂ２７基因阳性,占分析的２９．２％（７／２４）。７例Ｂ２７基因阳性病例中男５例,女２例,平均年龄１０．４岁。结论：Ｂ２７检测可作为诊断或鉴别诊断幼年强直性脊椎炎的重要指标,利于疾病病鉴别和预后估计。     

少儿强直性脊柱炎与幼儿类风湿性关节炎HLA-B27亚型的鉴别诊断

目的：探讨HLA－B27等位基因亚型与少年强直性脊柱炎和幼年类风湿性关节炎的关联。方法：用PCR－SSP方法对74人HLA－B27等位基因亚型进行研究，其中少年强直性脊柱炎32例，幼年类风湿性关节炎28例，5个家系中患者的父亲或母亲5例，正常对照组9例，并进行关联分析。结果：本组人群的HLA－B27等位基因由HLA－B*2704、*2705、*2702、*2707 4种亚型组成，其中少年强直性脊柱炎患者HLA－B27等位基因亚型频率为B*2704 56.25%、B*2705 40.63%、B*2702 3.13%；幼年类风湿性关节炎HLA－B27等位基因亚型频率为B*2705 60．7％、B*2704 28．57％、B*2702 3．57％及B*2707为7．14％；少年强直性脊柱炎与幼年类风湿性关节炎结果比较，HLA－B*2704基因频率在少年强直性脊柱炎组高于幼年类风湿性关节炎组（RR＝3．21，P＜0．05）。结论：少年强直性脊柱炎与HLA－B*2704等位基因亚型关联。对HLA－B27等位基因亚型的检测可成为少年强直性脊柱炎和幼年类风湿性关节炎鉴别诊断中一个有价值的实验指标。     

Detection of IL-2 at mRNA and protein levels in synovial infiltrates from inflammatory arthropathies using biotinylated oligonucleotide probes in situ.

A non-radioactive in situ hybridization method for IL-2 mRNA detection based on the use of four biotinylated oligonucleotide probes, plus appropriate positive and negative control probes was developed and applied to synovial surgical and needle biopsies from rheumatoid arthritis (RA), spondyloarthropathy (SpA), psoriatic arthritis (PsA) and juvenile chronic arthritis (JCA) patients. In eight surgical biopsies (six RA, one SpA, one PsA) this non-radioactive system showed similar sensitivity to that of a previously described 32P-labelled probe system, and in addition detected IL-2 mRNA in five out of seven biopsies from SpA and PsA patients and in two out of two JCA needle biopsies. IL-2 mRNA was found in the absence of IL-2 protein in RA biopsies (six surgical, 12 needle), but variable amounts of IL-2 protein were detected in six out of seven needle biopsies from SpA, PsA and JCA patients, where CD3+ lymphoid infiltrates were present. These data suggest differences in IL-2 regulation and expression in RA and non-RA inflammatory arthropathies.