HLA antigens in Japanese patients with psoriatic arthritis

Clinical features of psoriatic uveitis in Japanese patients

PURPOSE

To investigate the clinical features of psoriatic uveitis in Japanese patients.

METHODS

Clinical features of 13 consecutive patients with psoriatic uveitis treated at our facility were retrospectively examined using medical records. In this study, we collected data about psoriasis type, uveitis laterality, onset type, HLA types, visual acuity, ocular inflammation localization, anterior segment findings, funduscopy findings, complications, recurrence, and medical treatments for uveitis and skin diseases.

RESULTS

The cohort comprised ten males and three females (43.6 ± 7.1 years old), and types of psoriasis included psoriasis vulgaris (seven cases), psoriatic arthritis (four cases), pustular psoriasis (three cases) and psoriatic erythroderma (one case). Two cases represented complicated cases of pustular psoriasis and psoriatic arthritis. Seven cases were unilateral, and six cases were bilateral. All cases had acute non-granulomatous anterior uveitis, whereas panuveitis occurred in one case. Furthermore, macular edema and vascular leakage on fluorescein angiography occurred in four cases, and hyperemic disc occurred in two cases. Recurrence occurred in nine cases. In addition to topical corticosteroid treatment, eight cases underwent oral immunosuppressive treatment or biologics. All six cases undergoing HLA typing were HLA-A2 positive.

CONCLUSIONS

Cases of psoriatic uveitis in Japan appear to present with acute non-granulomatous uveitis; other symptoms may include macular edema, retinal vasculitis, or hyperemic disc.

Psoriasis Arthropathy and HLA-B51: Report of 5 Cases

Psoriasis arthropathy (PsA) is a chronic inflammatory arthropathy characterized by the association of arthritis with psoriasis. Although the precise mechanisms of PsA still remain obscure, several genetic and environmental factors have been suggested to play important roles. HLA-B51 has been strongly associated with Behçet's disease; however, its association with PsA has not been documented. We describe herein five Japanese patients (4 males and 1 female) with PsA and positive for HLA-B51. The clinical forms defined by Moll and Wright revealed that the polyarticular pattern was noted in two cases, and oligoarticular, distal, and spondyloarthropathy patterns were noted in one case each. Positive rheumatoid factor was detected in one patient, and antinuclear antibody in two patients. The other HLA subclasses were A2 and A31 in 3 cases, respectively. HLA-B51 was detected in 5 out of 17 patients with PsA examined in our department; in contrast, HLA-B51 was not detected in 17 patients with psoriasis vulgaris. Our observations suggest that HLA-B51 may play a role in the pathogenesis of PsA in the Japanese population.

Structural and functional distinctiveness of HLA-A2 allelic variants

Human leukocyte antigen (HLA) class I molecules are involved in the presentation of antigenic peptides to CD8(+) cytotoxic T lymphocytes (CTLs), which is important for the development of cellular immunity during viral infections and in cancers. HLA-A2 is one of the most frequent HLA class I specificities and thus is extensively studied structurally and functionally. Since its discovery, more than 300 allelic variants of this HLA specificity have been recorded. Among the HLA-A2 allelic variants, HLA-A*02:01 is the most prevalent, hence commonly used as a model to study HLA-A2-restricted CTL responses. However, HLA-A2 alleles are unevenly distributed globally such that HLA-A2 allelic variants besides A*02:01 are expressed at considerably high frequencies in Asian and African populations. Furthermore, increasing evidence of variations in the peptide-binding repertoire and CTL responses among HLA-A2 allelic variants suggests the need to understand these differences among various frequently expressed HLA-A2 molecules. In this review, the structural and functional distinctiveness of HLA-A2 allelic variants will be discussed.

Psoriatic arthritis in Asia

Geographic or ethnic differences in the occurrence of disease often provide insights into causes of disease and possible opportunities for disease prevention. A wide variation on the incidence and prevalence of PsA was reported in different countries. The prevalence in China was similar to the rest of the world, whereas the incidence and prevalence of PsA was much lower in Japan. Among patients with psoriasis, 6-42% of the Caucasians were reported to have PsA, but figures were lower from Asian countries (1-9%). Divergent distribution of HLA in different ethnic groups and other genetic determinants may account for these differences in prevalence. PsA affects men and women almost equally in Chinese, Japanese and Iranians, which is similar to their Caucasian counterparts. Polyarthritis developing in the fourth decade was the commonest pattern of arthritis among Chinese, Indians, Iranians, Kuwaiti Arabs and Malays. Arthritis mutilans and eye lesions have rarely been reported in Asian countries. Chinese patients with nail disease and DIP joints involvement have a significantly higher risk of developing deformed joints. More data are required on the safety, efficacy and cost effectiveness of TNF blockers for the treatment of PsA in Asia. Premature atherosclerosis has been recognized as an important co-morbidity in Asian patients with PsA. Increased prevalence of traditional cardiovascular risk factors associated with PsA suggested that the two conditions may share the same inflammatory pathway. Carotid intima-media thickness can identify PsA patients with subclinical atherosclerosis who may benefit from early intervention.

[A case of pityriasis rubra pilaris associated with rapidly progressive finger joint destruction]

A 40-year-old female noticed edema of the lower limbs in March 1995. Nephrotic syndrome due to membranous nephropathy was diagnosed and administration of high-dose corticosteroids resulted in incomplete remission. Progressively enlarging, red scaling skin lesions developed concomitantly from the scalp to the extremities. Pityriasis rubra pilaris (PRP) was diagnosed in 1996 in the Department of Dermatology at Sapporo Medical University hospital. Various treatments proved ineffective. Arthritis of the finger joints developed in July 1999, and proteinuria recurred in April 2000. She was admitted to our department in August 2000. Physical examination on admission revealed marked swelling of both distal interphalangeal (DIP) joints and the right fourth proximal interphalangeal (PIP) joint. Results of testing for antinuclear antibody, rheumatoid factor, and HLA-B27 were all negative. Radiography of the hands revealed destruction of the DIP and PIP joints where MRI indicated the presence of synovitis. Bone scintigraphy demonstrated accumulation in bilateral metatarso-phalangeal joints and the left sacroiliac joint. Arthritis associated with PRP was diagnosed, as both PRP and psoriasis represent keratinizing disorders of the skin and clinical features in the present case resembled those of psoriatic arthritis. Despite administration of high-dose corticosteroids, destruction of finger joints progressed rapidly. Administration of cyclosporine in April 2002 improved arthritic symptoms. Cases of PRP accompanied by arthritis need to be accumulated to allow analysis of the pathogenesis and clinical picture of this association.

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.

Genetic aspects of susceptibility, severity, and clinical expression in ankylosing spondylitis

While twin studies have previously demonstrated high heritability of susceptibility to ankylosing spondylitis (AS), it is only recently that the involvement of genetic factors in determining the severity of the disease has been demonstrated. The genes involved in determining the rate of ankylosis in AS are likely to be different from those involved in the underlying immunologic events, and represent important potential targets for treatment of AS. This article will describe the progress that has been made in the genetic epidemiology of AS, and in identifying the genes involved.

The association of psoriasis with human leukocyte antigens in Korean population and the influence of age of onset and sex

To identify HLA markers that may contribute to the genetic susceptibility of Koreans to psoriasis, we studied 84 psoriasis patients, with serologic HLA types of A, B, and genotypes of HLA-Cw, DRB1, DQA1, DQB1, DPB1 alleles. The distribution of HLA markers and the associated haplotypes were analyzed according to age and sex. HLA-Cw*0602 showed the strongest association with psoriasis (relative risk = 36.0, p < 10-8, Pc < 8 x 10-7). The frequencies of A1 (relative risk = 17.0, p < 9 x 10-7, Pc < 7 x 10-5), A30 (relative risk = 5.5, p < 2 x 10-5, Pc < 0.001), B13 (relative risk = 5.6, p < 4 x 10-6, Pc < 3 x 10-4), B37 (relative risk = 30.3, p < 7 x 10-7, Pc < 6 x 10-5), DRB1*07 (relative risk = 5.9, p < 2 x 10-6, Pc < 8 x 10-5), DRB1*10 (relative risk = 26.4, p < 4 x 10-6, Pc < 3 x 10-4), DQA1*02 (relative risk = 6.2, p < 5 x 10-7, Pc < 4 x 10-4), DQB1*02 (relative risk = 2.5, p < 0.005, Pc = ns) and DPB1*1701 (relative risk = 24.6, p < 9 x 10-6, Pc < 7 x 10-4) were also significantly increased in Korean psoriasis patients. Type I and type II psoriasis were subdivided into groups of below and above 30 y of age, because of the significant difference found in HLA-Cw*0602 phenotype frequency between the two groups (83.9% vs. 54.5%, p < 0. 009). In addition to HLA-Cw*0602, the frequencies of B37 and DPB1*1701 were significantly higher in type I as opposed to type II psoriasis. HLA-A30-B13-Cw*0602-DRB1*07-DQA1* 02-DQB1*02 was identified as a high risk haplotype. This was particularly true at an early age in the female. HLA-A33-B44-Cw*1401-DRB1*13-DQA1* 01-DQB1*06-DPB1*0401 was defined as a protective haplotype for psoriasis. The extended haplotype HLA-A1-B37-Cw*0602-DRB1*10-DQA1*01-DQB1*05 was discovered to be a high-risk factor in Koreans. To summarize, this study demonstrates the differential association of HLA according to sex, and identifies a newly found high-risk haplotype and a protective haplotype in Korean psoriasis patients.

The immunogenetics of the seronegative spondyloarthropathies

In none of the rheumatic diseases has the genetic contribution to pathogenesis been so well characterized as in the seronegative spondyloarthropathies. Most important has been the elucidation of the structure and effect on disease expression of HLA-B27, where 11 subtypes have been distinguished to date. These vary in frequency in different ethnic groups and seem to show differential disease associations. The high frequency of this gene in patients with the seronegative spondyloarthropathies, especially ankylosing spondylitis (AS) and Reiter's syndrome (RS)/reactive arthritis (ReA), has emerged as probably the best example of a disease association with a hereditary marker. Other HLA genes, in addition to HLA-B27, have been implicated in psoriasis and psoriatic arthritis. These include those from the HLA-C locus and from HLA-DR. In addition, recent family studies have implicated other genes outside the MHC that further enhance the susceptibility to AS.

Linkage analysis of human leukocyte antigen (HLA) markers in familial psoriasis: strong disequilibrium effects provide evidence for a major determinant in the HLA-B/-C region

Although psoriasis is strongly associated with certain human leukocyte antigens (HLAs), evidence for linkage to HLA markers has been limited. The objectives of this study were (1) to provide more definitive evidence for linkage of psoriasis to HLA markers in multiplex families; (2) to compare the major HLA risk alleles in these families with those determined by previous case-control studies; and (3) to localize the gene more precisely. By applying the transmission/disequilibrium test (TDT) and parametric linkage analysis, we found evidence for linkage of psoriasis to HLA-C, -B, -DR, and -DQ, with HLA-B and -C yielding the most-significant results. Linkage was detectable by parametric methods only when marker-trait disequilibrium was considered. Case-control association tests and the TDT identified alleles belonging to the EH57.1 ancestral haplotype as the major risk alleles in our sample. Among individuals carrying recombinant ancestral haplotypes involving EH57. 1, the class I markers were retained selectively among affecteds four times more often than among unaffecteds; among the few affected individuals carrying only the class II alleles from the ancestral haplotype, all but one also carried Cw6. These data show that familial and "sporadic" psoriasis share the same risk alleles. They also illustrate that substantial parametric linkage information can be extracted by accounting for linkage disequilibrium. Finally, they strongly suggest that a major susceptibility gene resides near HLA-C.

The effect of HLA-DR genes on susceptibility to and severity of ankylosing spondylitis

OBJECTIVE

To analyze the effect of HLA-DR genes on susceptibility to and severity of ankylosing spondylitis (AS).

METHODS

Three hundred sixty-three white British AS patients were studied; 149 were carefully assessed for a range of clinical manifestations, and disease severity was assessed using a structured questionnaire. Limited HLA class I typing and complete HLA-DR typing were performed using DNA-based methods. HLA data from 13,634 healthy white British bone marrow donors were used for comparison.

RESULTS

A significant association between DR1 and AS was found, independent of HLA-B27 (overall odds ratio [OR] 1.4, 95% confidence interval [95% CI] 1.1-1.8, P = 0.02; relative risk [RR] 2.7, 95% CI 1.5-4.8, P = 6 x 10(-4) among homozygotes; RR 2.1, 95% CI 1.5-2.8, P = 5 x 10(-6) among heterozygotes). A large but weakly significant association between DR8 and AS was noted, particularly among DR8 homozygotes (RR 6.8, 95% CI 1.6-29.2, P = 0.01 among homozygotes; RR 1.6, 95% CI 1.0-2.7, P = 0.07 among heterozygotes). A negative association with DR12 (OR 0.22, 95% CI 0.09-0.5, P = 0.001) was noted. HLA-DR7 was associated with younger age at onset of disease (mean age at onset 18 years for DR7-positive patients and 23 years for DR7-negative patients; Z score 3.21, P = 0.001). No other HLA class I or class II associations with disease severity or with different clinical manifestations of AS were found.

CONCLUSION

The results of this study suggest that HLA-DR genes may have a weak effect on susceptibility to AS independent of HLA-B27, but do not support suggestions that they affect disease severity or different clinical manifestations.

Psoriatic arthritis associated with dilated cardiomyopathy and Takayasu's arteritis

A 40-year-old Japanese man with psoriatic arthritis (PA) involving the spine, sacroiliac and peripheral joints presented with dyspnoea and ankle oedema. Blood pressure was 180/110 and 114/80 mmHg in the right and left upper arms, respectively. Examinations showed left ventricular dilatation and diffuse hypokinesis of the left ventricle, with no involvement of the coronary arteries. Aortography detected total occlusion of the left subclavian artery and stenosis of the origin at the right renal artery. Dilated cardiomyopathy and Takayasu's arteritis associated with PA was diagnosed. A few cases of PA have been reported in association with cardiovascular diseases, but the association of these three diseases has not been documented in the literature to date. Dermatologists need to be aware of cardiovascular manifestations in patients with PA, because cardiovascular diseases are not rare in other seronegative spondyloarthropathies.

Significance of antibodies to streptococcal M protein in psoriatic arthritis and their association with HLA-A*0207

Psoriatic arthritis (PA) is an immune disease associated with HLA-A2 in the Japanese population. To investigate mechanisms the association between HLA-A2 and PA, we examined in vivo immune responsiveness to Streptococcus pyogenes. Recombinant M proteins for the subtype specific N-terminal half (AB region) and conserved C-terminal half (C region) were produced separately. IgG antibody level against each region was measured by ELISA in 31 PA patients, 88 patients with psoriasis vulgaris, 6 patients with rheumatoid arthritis and 77 healthy controls. We found that IgG antibody levels against the C region were markedly higher in the PA patient group than in the other disease groups or controls. Further, IgG antibody levels were higher in PA patients with spondylitis and polyarticular arthritis than in PA patients with rheumatoid-like arthritis and arthritis mutilans. In contrast, no significant difference in the IgG antibody levels against the AB region was observed among the tested groups. HLA-A2 DNA typing showed that HLA-A*0207 was associated with PA (RR = 17.6; pcorr < 0.01) and the IgG antibody responses to the C region correlated well with the presence of HLA-A*0207. These results suggest that streptococcal infection may be involved in the pathogenesis of PA by participating in the HLA-linked immune responsiveness.

Immune response to Streptococcus pyogenes and the susceptibility to psoriasis

Monoclonal antibodies directed against type 12 Group A streptococcal cell wall antigens cross-react with nuclei and cytoplasm of cells from skin and synovium from controls, uninvolved skin of psoriatics and psoriatic plaques. Patients with psoriasis had high serum titres of antibody against the M12 (C-region) streptococcal antigen compared to controls. An abnormal immune response directed against a "self' antigen after initiation by Group A streptococcal infection may play an important role in the exacerbation or development of psoriasis.