Clinical significance of detecting HLA-DR, 14-3-3η protein and d-dimer in the diagnosis of rheumatoid arthritis.

AIM: To investigate the clinical significance of detecting several biomarkers collectively in the diagnosis of rheumatoid arthritis (RA). METHODS: 128 RA patients, 174 non-RA patients and 80 healthy controls were enrolled. HLA-DR4 and HLA-DR53 were detected by the PCR-SSP method, 14-3-3η protein, anti-CCP and anti-Sa were detected by ELISA and DD was detected by latex immunoturbidimetric assay. RESULTS: The positive rates of HLA-DR4, HLA-DR53, 14-3-3η protein, anti-CCP and anti-Sa were obviously higher in the RA group (43.8, 38.3, 51.6, 80 and 40.6%, respectively); anti-CCP was of highest sensitivity (79.68%), highest specificity (97.5%) and Youden index (0.77). The AUC of 14-3-3η protein, DD, anti-CCP, anti-Sa were 0.813, 0.859, 0.930, 0.861, respectively. CONCLUSION: All biomarkers were strongly correlated risk factors for RA; the combination of multiple biomarkers might be of help for diagnostic and therapeutic strategies in RA of recent onset.

Collateral Damage: Insulin-Dependent Diabetes Induced With Checkpoint Inhibitors.

Insulin-dependent diabetes may occur in patients with cancers who are treated with checkpoint inhibitors (CPIs). We reviewed cases occurring over a 6-year period at two academic institutions and identified 27 patients in whom this developed, or an incidence of 0.9%. The patients had a variety of solid-organ cancers, but all had received either anti-PD-1 or anti-PD-L1 antibodies. Diabetes presented with ketoacidosis in 59%, and 42% had evidence of pancreatitis in the peridiagnosis period. Forty percent had at least one positive autoantibody and 21% had two or more. There was a predominance of HLA-DR4, which was present in 76% of patients. Other immune adverse events were seen in 70%, and endocrine adverse events in 44%. We conclude that autoimmune, insulin-dependent diabetes occurs in close to 1% of patients treated with anti-PD-1 or -PD-L1 CPIs. This syndrome has similarities and differences compared with classic type 1 diabetes. The dominance of HLA-DR4 suggests an opportunity to identify those at highest risk of these complications and to discover insights into the mechanisms of this adverse event.

Genetic and Environmental Interactions Modify the Risk of Diabetes-Related Autoimmunity by 6 Years of Age: The TEDDY Study.

OBJECTIVE: We tested the associations between genetic background and selected environmental exposures with respect to islet autoantibodies and type 1 diabetes. RESEARCH DESIGN AND METHODS: Infants with HLA-DR high-risk genotypes were prospectively followed for diabetes-related autoantibodies. Single nucleotide polymorphisms (SNPs) came from the Illumina ImmunoChip and environmental exposure data were by parental report. Children were followed to age 6 years. RESULTS: Insulin autoantibodies occurred earlier than GAD antibody (GADA) and then declined, while GADA incidence rose and remained constant (significant in HLA-DR4 but not in the DR3/3 children). The presence of SNPs rs2476601 (PTPN22) and rs2292239 (ERBB3) demonstrated increased risk of both autoantibodies to insulin (IAA) only and GADA only. SNP rs689 (INS) was protective of IAA only, but not of GADA only. The rs3757247 (BACH2) SNP demonstrated increased risk of GADA only. Male sex, father or sibling as the diabetic proband, introduction of probiotics under 28 days of age, and weight at age 12 months were associated with IAA only, but only father as the diabetic proband and weight at age 12 months were associated with GADA only. Mother as the diabetic proband was not a significant risk factor. CONCLUSIONS: These results show clear differences in the initiation of autoimmunity according to genetic factors and environmental exposures that give rise to IAA or GADA as the first appearing indication of autoimmunity.

Evaluation of the role of HLA-DR antigens in Japanese type 1 autoimmune hepatitis.

BACKGROUND: The role of HLA-DR antigens in the clinicopathological features of autoimmune hepatitis (AIH) is not clearly understood. We examined the implications of HLA-DR antigens in Japanese AIH, including the effect of HLA-DR4 on the age and pattern of AIH onset, clinicopathological features, and treatment efficacy. METHODS: A total of 132 AIH patients consecutively diagnosed and treated in 2000-2014 at 2 major hepatology centers of eastern Tokyo district were the subjects of this study. The frequency of HLA-DR phenotypes was compared with that in the healthy Japanese population. AIH patients were divided into HLA-DR4-positive or HLA-DR4-negative groups and further sub-classified into elderly and young-to-middle-aged groups, and differences in clinical and histological features were examined. Clinical features associated with the response to immunosuppressive therapy were also determined. RESULTS: The frequency of the HLA-DR4 phenotype was significantly higher in AIH than in control subjects (59.7 % vs. 41.8 %, P < 0.001), and the relative risk was 2.14 (95 % CI; 1.51-3.04). HLA-DR4-positive AIH patients were younger than HLA-DR4-negative patients (P = 0.034). Serum IgG and IgM levels were higher (P < 0.001 and P = 0.007, respectively) in HLA-DR4-positive patients. These differences were more prominent in elderly AIH patients. However, there was no difference in IgG and IgM levels between HLA-DR4-positive and HLA-DR4-negative patients of the young-to-middle-aged group. There were no differences in the histological features. In patients with refractory to immunosuppressive therapy, higher total bilirubin, longer prothrombin time, lower serum albumin, and lower platelet count were found. Imaging revealed splenomegaly to be more frequent in refractory patients than in non-refractory patients (60.0 % vs. 30.8 %, P = 0.038). HLA-DR phenotype distribution was similar regardless of response to immunosuppressive therapy. CONCLUSIONS: HLA-DR4 was the only DR antigen significantly associated with Japanese AIH. The clinical features of HLA-DR4-positive AIH differed between elderly patients and young-to-middle-aged patients. Treatment response depended on the severity of liver dysfunction but not on HLA-DR antigens.

Autoantibody and human leukocyte antigen profiles in children with autoimmune liver disease and their first-degree relatives.

OBJECTIVE: Familial clustering of juvenile autoimmune liver disease (AILD), including autoimmune hepatitis and autoimmune sclerosing cholangitis (ASC), is rare, despite a high prevalence of autoimmune disorders in AILD families. METHODS: To investigate this discrepancy, we measured autoantibodies diagnostic for AILD, anti-nuclear, anti-smooth muscle, anti-liver kidney microsomal type 1, anti-liver cytosol type 1, and anti-soluble liver antigen antibodies, and human leukocyte antigen profiles in 31 patients and 65 of their first-degree relatives (FDR). The autoantibody profile was compared with that of 42 healthy subjects (HS). RESULTS: Autoantibodies were detected in 71% (22/31) patients. Anti-nuclear antibody or anti-smooth muscle antibody were present in 4/65 FDR (6.2%). HS were negative for all autoantibodies. The frequencies of homozygous HLA DRB1*0301 (DR3) genes and haplotype A1-B8-DR3 were higher in the patients (25% and 43%) than in FDR (9% and 27%) and HS (0% and 16%). The frequencies of disease-protective genes DR4 and/or DR15 were lower in the patients (25%) than in FDR (42%) and HS (42%). Only 1 family contained 2 patients with AILD, 1 with ASC and 1 with primary sclerosing cholangitis. Both patients possessed A1-B8-DR3 genes, the ASC being homozygous and the primary sclerosing cholangitis heterozygous. Six FDR had nonhepatic autoimmune disorders, none being autoantibody positive. CONCLUSIONS: Homozygosity for DR3 plays a major role in the predisposition to juvenile AILD. Diagnostic autoantibodies for AILD are rare among patients' FDR and not linked to clinical manifestation of AILD.

Study of association between HLA-DR4 and DR53 and autoantibody detection in rheumatoid arthritis.

The present study explored the association between human leukocyte antigen (HLA)-DR4, DR53, and auto antibodies in rheumatoid arthritis (RA) and its clinical significance. A total of 305 patients with RA and 50 healthy subjects who underwent medical examination were evaluated. HLA-DR4 and HLA-DR53 and auto antibodies were detected. The results showed that frequencies of HLA-DR4 and HLA-DR53 alleles in RA patients were 42.95% and 54.75%, respectively, which were significantly different from those in control group (p < 0.01). Frequencies of anti-cyclic citrullinated peptide antibody (CCP), anti-RA33, anti-keratin antibody (AKA), and anti-nuclear antibody (ANA) in RA patients (n = 305) were 72.13%, 36.39%, 44.92%, and 60.98%, respectively. Results of rheumatoid factor (RF) and C-reactive protein (CRP) were 148.29 ± 391.01 IU/mL and 18.14 ± 26.87 mg/L, respectively, which were significantly different from those in control group (p < 0.01, t-test). The results indicated that the HLA- DR4 gene was clearly associated with susceptibility of RA. Combined detection of related auto antibodies might improve diagnosis rate of RA significantly, and the positive rate was higher than that for a single antibody.

Clinical features of elderly Chinese patients with autoimmune hepatitis.

BACKGROUND/AIMS: To study the clinical features of elderly Chinese patients with autoimmune hepatitis. MATERIALS AND METHODS: The clinical features of 36 patients diagnosed at age >60 years were compared with those of 39 patients aged <50 years. RESULTS: The M:F ratio was 1:35 (>60 years) vs. 3:36 (<50 years). The patients >60 years had a higher frequency of cirrhosis at presentation than the patients <50 years (52.8% vs. 15.4%, p=0.001). The patients >60 years also had a significantly increased incidence of ascites at presentation (41.7% vs. 10.3%, p=0.001) and lower serum albumin levels (p=0.037). There were significant differences between older and younger patients with respect to the frequencies or titers of anti-nuclear antibody (46.2% vs. 83.3%, p=0.011). HLA DR3 positivity occurred more frequently in the patients <50 years than in those >60 years (59.0% vs. 19.4%, p<0.001), whereas HLA DR4 occurred more often in the patients >60 years (63.9% vs. 25.6%, p=0.001). Treatment failure occurred more frequently in the patients <50 years (28.2% vs. 9.1%, p=0.041). However, there were no significant differences between the groups with respect tomode of onset, other clinical signs at presentation biochemical parameters, and smooth muscle antibody positivity. CONCLUSION: Elderly patients have a greater frequency of cirrhosis at presentation, anti-nuclear antibody, HLA DR4 positivity than patients <50 years, and they have a lower occurrence of treatment failure. Conventional corticosteroid regimens may be an effective management for older patients with autoimmune hepatitis.

[Association of HLA-DR4, PAD4, and STAT4 expression in the peripheral blood with disease activity in patients with rheumatoid arthritis].

OBJECTIVE: To explore the association of the expressions of human leukocyte antigen (HLA)-DR4, peptidyl arginine deiminase type4(PAD4), and signal transducer and activator of transcription 4 (STAT4) in the peripheral blood with the disease activity in patients with rheumatoid arthritis (RA). METHODS: Twenty-four RA patients in active stage (DAS28 score>or=2.6) and 14 RA patients in remission stage (DAS28 score<2.6) were enrolled in this study, with 12 healthy volunteers as the control. The QuantiGene Plex method was used to measure the expression level of HLA-DR4, PAD4, and STAT4 mRNA, and the relationship between the expressions of these genes and the DAS28 score, levels of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) and rheumatoid factor (RF) was analyzed. RESULTS: The expressions of HLA-DR4, PAD4, and STAT4 were significantly higher in RA patients than in the healthy controls (P<0.05). The level of HLA-DR4 mRNA in the two RA groups showed no significant difference, but was significantly higher than that in the healthy controls. HLA-DR4 expression was not found to correlated to DAS28 score, anti-CCP antibody level or RF in the RA patients. The expressions of PAD4 and STAT4 were significantly different between the two RA groups (P<0.05). In the RA patients, PAD4 mRNA expression was positively correlated to DAS28 and anti-CCP antibody level (P<0.05), and STAT4 expression showed positive correlations to DAS28 and RF levels (P<0.05). CONCLUSION: HLA-DR4, PAD4 and STAT4 are overexpressed in RA patients and may be involved in the pathogenesis of RA. The expressions of PAD4 and STAT4, but not HLA-DR4, are closely related to the disease activity of RA. Detection of peripheral blood PAD4 and STAT4 expressions can be helpful for evaluating the disease activity of RA.

Interferon-gamma is increased in patients with primary Sjogren's syndrome and Raynaud's phenomenon.

OBJECTIVES: To determine the prevalence of Raynaud's phenomenon (RP) in patients with primary Sjogren's syndrome (pSS) and to identify clinical and immunological characteristics associated with this manifestation. Since increased interferon-gamma (INF-gamma) has been associated with RP, we also compared the INF-gamma production in pSS patients with or without RP. METHODS: RP was diagnosed if pSS patients presented with characteristic sequence of skin color changes of the digits. In uncertain cases noninvasive vascular tests were performed by ultrasound examination. The secretion of INF-gamma by peripheral blood mononuclear cells was assessed by enzyme-linked immunospot analysis. Further, we examined the expression of different lymphocyte activation markers (CD25, CD45RO, CD69) on CD4+ T-cells by flow cytometric analysis. RESULTS: Thirty-six of 108 patients with pSS had RP. In these patients we found a significantly increased number of INF-gamma-secreting peripheral blood mononuclear cells compared with patients without RP or to healthy controls. Further, in patients with RP a significantly increased percentage of CD25-positive T-helper cells was detectable. In addition we found an association of leukopenia, thyroiditis, and lower C3 levels with RP in pSS patients. CONCLUSIONS: These results suggest a pathogenic role of INF-gamma in pSS patients with RP. Whether the RP is immune-mediated or whether INF-gamma directly causes vasospasm still remains to be elucidated.

Clinical features of Japanese elderly patients with type 1 autoimmune hepatitis.

OBJECTIVE: In Caucasian type 1 autoimmune hepatitis patients with a main susceptibility of human leukocyte antigen DR3 and DR4, elderly patients have a higher frequency of concurrent autoimmune disease and cirrhosis at presentation. However, in Japanese patients, the disease is dominantly associated with DR4, and their clinical features may be different from those of previous reports. In this study, we assessed the clinical features of Japanese elderly patients with type 1 autoimmune hepatitis. METHODS: We investigated 160 consecutive patients with type 1 autoimmune hepatitis, consisting of 34 elderly patients (> or = 65 years) and 126 younger patients (< 65 years). RESULTS: There were no differences in form of clinical onset, frequencies of concurrent autoimmune disease, positive proportions of anti-nuclear antibody and/or anti-smooth muscle antibody, and human leukocyte antigen DR status between the two groups. However, the elderly patients had lower serum levels of albumin (p=0.0049), and higher frequencies of cirrhosis (F4) and pre-cirrhosis (F3) (p=0.014) compared with the younger patients. In contrast, in elderly patients, the cumulative incidental rate of the normalization of serum alanine aminotransferase levels within 6 months after the introduction of initial treatment was higher in those treated with prednisolone > or = 20 mg/day than those treated only with ursodeoxycholic acid (p=0.001). CONCLUSION: We speculate that more years may pass between the occurrence of the disease and the presentation in Japanese elderly patients than in younger patients, and we considered that, even in elderly patients, those with advanced fibrosis should be treated with prednisolone in order to prevent progress of the disease into liver failure.

Incidence of juvenile idiopathic arthritis in children in Estonia: a prospective population-based study.

OBJECTIVE: To study the incidence rate of juvenile idiopathic arthritis (JIA) and its clinical subtypes in Estonia, to follow the course of the disease in newly diagnosed patients for 2 years, and to find the frequency of human leucocyte antigens (HLA) B27, DR1 and DR4 in JIA patients. METHOD: A population-based study involving prospective registration of new cases of JIA in 1998-2000 and their clinical follow-up for 2 years. RESULTS: In 1998-2000, 162 new cases of JIA were diagnosed. The mean annual incidence rate of JIA was 21.7 per 100 000 children aged 0-15 years (22.9 in girls and 19.3 in boys). During the investigation period, the incidence rate rose 3.5-fold. Oligoarthritis was the most frequent subtype (mean annual incidence rate of 11.7 per 100 000), followed by seronegative polyarthritis (4.4 per 100 000). HLA-DR1, B27 and DR4 were found respectively in 44.4, 28.6 and 11.1% of cases in which the analysis was performed. In HLA-B27-positive patients, inflammation markers of blood remained at a high level for a longer period compared with HLA-B27-negative patients. CONCLUSIONS: This is the first population-based study on the epidemiology of juvenile arthritis in Estonia in which the new classification criteria defined by the International League of Associations for Rheumatology (ILAR) have been used. In addition to environmental factors, an increase in awareness among family doctors is a probable reason for the rise in incidence during the study period. HLA-B27 might have predictive value as a marker of chronicity of inflammation.

Perinatal and early childhood risk factors associated with rheumatoid factor positivity in a healthy paediatric population.

OBJECTIVE: To examine perinatal and childhood risk factors for the presence of rheumatoid factor in healthy children. METHODS: The Diabetes Autoimmunity Study in the Young (DAISY) is a longitudinal study of children at increased risk of type 1 diabetes, based on possession of human leucocyte antigen (HLA)-DR4 and DR3 alleles or a family history of diabetes. 651 children who participated in DAISY, with an average age of 6.4 (range 1-15) years, were tested for the presence of rheumatoid factor in their most recent serum sample. 23 children were positive for rheumatoid factor. Exposure data were collected prospectively by interview. HLA-DR4 alleles were identified using polymerase chain reaction-based Class II genotyping. RESULTS: While exploring risk factors for rheumatoid factor positivity in a multivariate model, several important interaction terms involving HLA-DR4 status suggested the need to evaluate risk factors in HLA-DR4-positive and HLA-DR4-negative children separately. In HLA-DR4-negative children, rheumatoid factor-positive infants were less likely to have been breast fed for >3 months (odds ratio (OR) 0.18; 95% confidence interval (CI) 0.04 to 0.99), more likely to have been exposed to non-parental tobacco smoke (OR 5.38; 95% CI 0.93 to 31.27) and more likely to be a race/ethnicity other than non-Hispanic white (OR 6.94; 95% CI 1.10 to 43.88) compared with rheumatoid factor-negative children, after adjusting for age, sex and maternal education. In HLA-DR4-positive children, there were no significantly associated risk factors for rheumatoid factor positivity. CONCLUSIONS: Risk factors for rheumatoid factor positivity in children vary by HLA-DR4 genotype. In HLA-DR4-negative children, breast feeding may decrease the risk, and environmental tobacco smoke may increase the risk, of autoimmunity.

Don't do anything rash!

BACKGROUND: Peripartum and postpartum dermatologic lesions may or may not be an indicator of morbidity or mortality for either the fetus or mother. CASE: Postpartum dermatologic lesions occurred in a 41-year-old multipara, 1 week after a repeat cesarean delivery for severe intrauterine growth restriction and nonreassuring fetal testing. The diagnosis, using histopathologic techniques, and the pharmacologic management are discussed. CONCLUSION: This case raises intriguing questions regarding prompt diagnosis, treatment, and the counseling of patients with dermatologic lesions with respect to current and future pregnancy outcomes.

Frequency and significance of antibodies to cyclic citrullinated peptide in type 1 autoimmune hepatitis.

OBJECTIVES: Determine the frequency, clinical phenotype, and prognostic implications of antibodies against cyclic citrullinated peptides in patients with type 1 autoimmune hepatitis. METHODS: Three hundred and ninety-five serum samples from 179 patients were tested by enzyme-linked immunosorbent assay, and findings correlated with clinical and histological features, frequency of HLA DR3 and DR4, and treatment outcome. RESULTS: Twenty patients (11%) had antibodies against cyclic citrullinated peptides. Seropositivity was associated with a higher frequency of rheumatoid arthritis (RA) (25 vs. 0%, P < 0.001). Patients with antibodies against cyclic citrullinated peptides also had a significantly greater occurrence of histological cirrhosis at presentation (47 vs. 20%, P = 0.01) and death from hepatic failure than seronegative patients (25 vs. 9%, P = 0.04). Cirrhosis at presentation occurred more commonly in the patients with antibodies against cyclic citrullinated peptides and RA than in the other patients (100 vs. 21%, P = 0.005). CONCLUSIONS: Antibodies against cyclic citrullinated peptides occur in a subgroup of patients with type 1 autoimmune hepatitis who have a greater occurrence of cirrhosis at presentation and death from hepatic failure. Their presence with RA at accession characterizes a subgroup with cirrhosis.

[Relationship between HLA-DR4/1 subtypes and T cell responses to type II collagen or anti-C II 263-272 antibodies].

OBJECTIVE: To investigate the relationship between HLA-DR4/1 subtypes and T cell responses to type II collagen or anti-CII 263-272 antibodies. METHODS: Peripheral blood mononuclear cells and sera were obtained from 70 rheumatoid arthritis (RA) patients. T cell proliferative responses to CII 263-272 were evaluated by [(3)H] thymidine incorporation assay. Antibodies specific to CII 263-272 were determined by ELISA. HLA-DR4/1 subtypes were analyzed by PCR-SSP. RESULTS: In HLA-DR4/1 positive group, T cell proliferative responses to CII 263-272 were observed in 55.6% RA patients and anti-CII 263-272 antibodies were present in 66.7% RA patients. In HLA-DR4/1 negative group, T cell proliferative responses to CII 263-272 were observed in 30.3% RA patients and anti-C II 263-272 antibodies were present in 34.8% RA patients. The number of positive antibodies to CII 263-272 or T cell proliferative responses to CII 263-272 in HLA-DR4/1 positive group were higher than in negative group. CONCLUSION: There is a relationship between HLA-DR4/1 subtypes and T cell responses to CII 263-272 or anti-CII 263-272 antibodies.

Clinical features of type 1 autoimmune hepatitis in elderly Italian patients.

BACKGROUND: The usual onset of type 1 autoimmune hepatitis occurs at puberty or around menopause, whereas disease presentation in the advanced age is less often reported. AIM: To assess the clinical, immunological and histological features of Type 1 autoimmune hepatitis in elderly Italian patients. METHODS: We assessed, at diagnosis, the clinical and immunological features of 76 consecutive Italian patients with type 1 autoimmune hepatitis, focusing particularly on a subgroup of 20 patients presenting at > or = 65 years (females 95%, median age 72 years, range 65-82). RESULTS: In comparison with the younger group, at the time of autoimmune hepatitis diagnosis, elderly Italian patients are more often asymptomatic (25% vs. 7%; P = 0.04), are more frequently positive for antinuclear autoantibodies (95% vs. 52%; P = 0.0004) and HLA-DR4 (45% vs. 18%; P = 0.03); among the extra-hepatic manifestations, autoimmune thyroid disorders are prevalent in the elderly group (25% vs. 5%; P = 0.02). However, no difference was observed in the histological/biochemical expression of the liver disease and response to immunosuppression. CONCLUSIONS: In elderly Italian patients, autoimmune hepatitis has typical serological and genetic characteristics, is more frequently asymptomatic, although prognosis and response to therapy is similar to that of younger patients. As a concomitant autoimmune thyroid disorder is common, autoimmune hepatitis should be suspected and investigated in elderly patients with autoimmune thyroid disorder and abnormal liver function tests.

Different contribution of class II HLA in fulminant and typical autoimmune type 1 diabetes mellitus.

AIMS/HYPOTHESIS: Fulminant type 1 diabetes, which is characterised by a markedly acute onset of diabetes and an absence of islet-related autoantibodies, accounts for 20% of type 1 diabetes in Japan. We aimed to clarify the contribution of the HLA subtype to fulminant type 1 diabetes in Japanese. METHODS: We determined the serological subtypes of HLA-A, -DR and -DQ in 115 patients with fulminant type 1 diabetes, 98 patients with typical type 1A diabetes and 190 normal control subjects. RESULTS: The frequency of HLA-DR4, but not DR9, was significantly higher in fulminant type 1 diabetes, while those of HLA-DR1, DR2, DR5 and DR8 were significantly lower than those in controls. In contrast, DR9 but not DR4 was more frequent and DR2 was extremely rare in typical type 1A diabetes. Haplotype analysis revealed that DR4-DQ4 was significantly more frequent, and both DR2-DQ1 and DR8-DQ1 were less frequent in fulminant diabetes. In type 1A diabetes, DR2-DQ1 was extremely rare while DR9-DQ3 was significantly more frequent. In the combination analysis, the homozygotes of DR4-DQ4 in fulminant type 1 diabetes and DR9-DQ3 in typical type 1A diabetes indicated high odds ratios (13.3 and 13.3, respectively). CONCLUSIONS/INTERPRETATION: Our results suggest that class II HLA contributes to the development of fulminant type 1 diabetes. Susceptibility and resistance of the HLA subtype to type 1 diabetes are distinct between fulminant and typical autoimmune type 1 diabetes.

Antibodies against cyclic citrullinated peptide are associated with HLA-DR4 in simplex and multiplex polyarticular-onset juvenile rheumatoid arthritis.

OBJECTIVE: Anti-cyclic citrullinated peptide (anti-CCP) antibodies have been detected in patients with juvenile rheumatoid arthritis (JRA), particularly in those with polyarticular, rheumatoid factor (RF)-positive JRA. Our objectives were to determine whether anti-CCP antibodies are associated with HLA-DR4 in children with polyarticular JRA, whether anti-CCP antibodies are associated with clinical features of disease, and whether affected sibling pairs (ASPs) with JRA are concordant for this antibody. METHODS: Stored serum samples obtained from 230 HLA-typed patients with JRA (77 with polyarticular-onset disease and 153 with pauciarticular- or systemic-onset disease), 100 JRA ASPs, and 688 healthy children were tested for anti-CCP antibodies and RF. RESULTS: Thirteen percent of the patients with polyarticular-onset JRA and 2% of the other JRA patients exhibited anti-CCP antibodies, compared with only 0.6% of the controls. Fifty-seven percent of RF-positive patients with polyarticular-onset JRA had anti-CCP antibodies. HLA-DR4-positive patients with polyarticular-onset JRA were more likely to have anti-CCP antibodies than were those without HLA-DR4 alleles (odds ratio [OR] 5.20, 95% confidence interval [95% CI] 1.30-20.9). Anti-CCP antibodies were associated with polyarticular onset (OR 7.46, 95% CI 1.99-28.0), a polyarticular disease course (OR 9.78, 95% CI 1.25-76.7), and erosive disease (OR 14.3, 95% CI 3.01-67.9). Concordance rates for anti-CCP antibodies among ASPs were statistically significant. CONCLUSION: These data demonstrate increased anti-CCP antibody formation in HLA-DR4-positive patients with polyarticular-onset JRA. The overall prevalence of anti-CCP antibodies in JRA is low, but a substantial proportion of RF-positive patients with polyarticular-onset JRA have these antibodies. Anti-CCP antibodies in JRA are associated with polyarticular onset, a polyarticular course, and erosive disease.

Mature high-affinity immune responses to (pro)insulin anticipate the autoimmune cascade that leads to type 1 diabetes.

Children at risk for type 1 diabetes can develop early insulin autoantibodies (IAAs). Many, but not all, of these children subsequently develop multiple islet autoantibodies and diabetes. To determine whether disease progression is reflected by autoantibody maturity, IAA affinity was measured by competitive radiobinding assay in first and subsequent IAA-positive samples from children followed from birth in the BABYDIAB cohort. IAA affinity in first positive samples ranged from less than 10(6) l/mol to more than 10(11) l/mol. High affinity was associated with HLA DRB1*04, young age of IAA appearance, and subsequent progression to multiple islet autoantibodies or type 1 diabetes. IAA affinity in multiple antibody-positive children was on average 100-fold higher than in children who remained single IAA positive or became autoantibody negative. All high-affinity IAAs required conservation of human insulin A chain residues 8-13 and were reactive with proinsulin. In contrast, most lower-affinity IAAs were dependent on COOH-terminal B chain residues and did not bind proinsulin. These data are consistent with the concept that type 1 diabetes is associated with sustained early exposure to (pro)insulin in the context of HLA DR4 and show that high-affinity proinsulin-reactive IAAs identify children with the highest diabetes risk.