Anti-cyclic Citrullinated Peptide Antibodies in Patients with Juvenile Idiopathic Arthritis

We analysed the presence of anti-cyclic citrullinated peptide (anti-CCP) and anti-keratin (AKA) antibodies of the IgG class in sera of patients with defined juvenile idiopathic arthritis (JIA) of various subgroups with more than one year duration of the disease. Enzyme-linked immunosorbent assay (Immunoscan RA, Eurodiagnostica, The Netherlands) and an indirect immunofluorescence (IIF) test on rat oesophagus substrate (ImmuGloTM, Immco Diagnostics, Buffalo, USA) were used for the detection and quantification of anti-CCP and AKA antibodies in 140 patients with JIA (64 male and 76 female) aged 2-47 years (median 16.5 years). Overall, anti-CCP were found in 7/140 (5.0%) patients including 3/52 RF negative polyarthritis, 2/18 RF positive polyarthritis, 1/15 enthesitis related arthritis and 1/5 unclassifiable arthritis. AKA were detected in 40/140 patients (28.6%, p =0.04) including 2/11 systemic arthritis, 2/32 oligoarthritis, 18/52 patients with RF negative polyarthritis (34.6%, p =0.01), 14/18 RF positive polyarthritis (77.8%, p =0.000002), 2/15 enthesitis related arthritis and 2/3 psoriatic arthritis. While simultaneous negativity for AKA and anti-CCP occurred in most (97/140; 69.3%) studied cases, simultaneous antibody positivity was found only in few (4/140; 2.9%) studied samples. We conclude that while AKA measured using IIF on rat esophagus can be detected approximately in one third of patients with definite JIA with more than 1 year duration of the disease, only rare occurrence of anti-CCP was observed. We conclude that AKA seem to be partly useful to confirm JIA diagnosis, however, useless to follow-up severity or activity in JIA patients. Anti-CCP do not have any additional value in JIA cohort in comparison to RA where their diagnostic and prognostic importance was reported.     

Share Epitope,Citrullinated Cyclic Peptide Antibodies and Smoking in Brazilian Rheumatoid Arthritis Patients

The events involved in the pathogenesis of rheumatoid arthritis (RA) still remain unclear, but certainly the etiology is multifactorial. Shared epitope (SE) of HLADRβ1 is the most important genetic risk factor. Environmental risk factors are less understood. Smoking is a candidate, associated with the rising of citrullinated cyclic peptide antibodies (anti-CCP). Anti-CCP antibodies are highly specific for RA. In this study, we investigated whether the association between anti-CCP production and smoking was influenced by carriage of SE in a highly miscegenated population of patients with RA. One hundred Brazilian patients were inquired about cigarette smoking. For all of them, DNA for HLA typing and serum to anti-CCP antibodies quantification were obtained. Forty-two were smokers and 58 were nonsmokers. The SE was present in 61 patients and the anti-CCP was positive in 71 patients. We found that, among smokers, 25 were SE-positive, 22 presented with anti-CCP and 3 without anti-CCP, and 17 were SE-negative, 9 presented with anti-CCP and 8 without anti-CCP (OR 6.5, 95% CI 1.40 to 30.20). These results suggest that environmental factors contribute to the raising of anti-CCP in individuals with HLA background to RA, smoking being a strong candidate.     

Increased Prevalence of Anti-Third Generation Cyclic Citrullinated Peptide Antibodies in Patients With Rheumatoid Arthritis and CREST Syndrome

To investigate the prevalence of anti-third generation cyclic citrullinated peptide antibodies (anti-CCP3) in patients with systemic connective tissue diseases, we assembled a training set consisting of 115 patients with rheumatoid arthritis (RA), 52 with Calcinosis, Raynaud’s phenomenon, oesophageal dysmotility, sclerodactyly, telangiectasia (CREST) syndrome, 21 with scleroderma, 20 with ankylosing spondylitis, 18 with reactive arthritis, 25 with juvenile rheumatoid arthritis (RA), 51 with osteoarthritis, 26 with mixed connective tissue disease, 23 with primary Sjogren’s syndrome, 74 with systemic lupus erythematosus, 49 with Polymyaglia rheumatica, and 39 with polymyositis/dermatomyositis. The commercial enzyme-linked immunosorbent assay (ELISA) was used to detect anti-CCP antibodies, including anti-CCP2 (regular, second generation of CCP antigen) and anti-CCP3 (third generation of CCP antigen) in disease-related specimens and normal controls. These serum samples were also evaluated for anti-centomere antibodies by anti-centromere ELISA kit. The higher frequencies of anti-CCP3 and anti-CCP2 were detected in 75.6 and 70.4% patients with RA, respectively. At the same time, anti-CCP3 (not anti-CCP2) was significantly increased in samples isolated from patients with CREST syndrome. The clinical sensitivity of IgG anti-CCP3 for the patients with CREST syndrome was 29% (15 of 52) and the specificity was 96% (384 of 397), with the exception of the RA group. The anti-centromere antibodies were significantly higher in patients with CREST only. The results of our study suggest that compared to anti-CCP2 assay, the new anti-CCP3 assay can enhance the clinical sensitivity for diagnosis of RA and, as an associate marker combined with anti-centromoere, can distinguish CREST syndrome from other systemic connective tissue diseases, especially RA. The clinical specificity of anti-CCP3 was lower than anti-CCP2 assay in diagnosis of RA because of the crossreaction to the patients with CREST syndrome.     

第二代抗环瓜氨酸肽抗体的检测在类风湿关节炎诊断中的意义

目的探讨抗环瓜氮酸肽（CCP）抗体的检测在类风湿关节炎（RA）诊断中的价值。方法ELISA法分别检测108例RA、89例非RA（其它风湿病患者）和78例健康体检者的抗CCP抗体；用间接免疫荧光法和速率散射比浊法检测抗角蛋白抗体（AKA）和类风湿因子（RF），分析CCP抗体的水平及与AKA、RF的相关性。结果抗CCP抗体的阳性率在RA中为87．4％（94／108），在非RA中为8．99％（8／89），正常人为0％（0／78）。3种抗体对RA诊断的敏感性和特异性分别为CCP87．4％、91．01％，AKA58．33％，82．24％，RF81．36％、75．35％。CCP抗体与AKA在RA患者血清中的阳性率之间差异非常显著，与RF差异不显著。3种方法的检测结果间存在相关性。结论用ELISA法检测血清中CCP抗体简便、结果可靠，对RA诊断具有高度的敏感性和特异性。     

抗突变型瓜氨酸波形蛋白抗体在诊断类风湿性关节炎中的意义

目的 探讨抗突变型瓜氨酸波形蛋白抗体(anti-mutated citrullinated vimentin antibody,Anti-MCV)在诊断类风湿性关节炎(rheumatoid arthritis,RA)中的价值.方法 选取确诊的RA患者51例(RA组)、非RA自身免疫性疾病患者36例(疾病对照组)和健康查体者30例(对照组)作为研究对象.根据临床资料计算DAS28评分,将RA组分为活动组和稳定组.采用酶联免疫吸附法(ELISA)检测血清中的抗MCV抗体、抗环瓜氨酸肽抗体(抗CCP抗体)及白细胞介素-6(IL-6)水平,采用免疫比浊法检测血清中C-反应蛋白(CRP)的浓度水平,并进行比较.结果 RA组抗MCV抗体的浓度水平显著高于非RA组和对照组(P均＜0.01);活动组抗MCV抗体的浓度水平显著高于稳定组和对照组(P均＜0.01);经Spearmau相关性分析,抗MCV抗体的浓度水平与CRP及IL-6呈正相关,而与DAS28无相关性;抗MCV抗体与抗CCP抗体的诊断效率无显著差异,但是灵敏度高于抗CCP抗体.结论 抗MCV抗体具有较高的灵敏度和特异性,并且能提示RA病情的活动情况,可以成为新的辅助RA诊断的血清学指标.     

抗环瓜氨酸肽抗体检测对类风湿关节炎的临床诊断价值

目的探讨抗环瓜氨酸肽抗体（抗CCP抗体）检测对类风湿关节炎（RA）诊断的意义。方法采用酶联免疫吸附试验（ELISA）检测115份人血清的抗CCP抗体,同时采用免疫透射比浊法定量检测类风湿因子（RF）,包括40例RA患者,45例其它风湿病患者,30名正常人;并分析抗CCP抗体与RF实验结果之间的相关性。结果在40例RA病人中,抗CCP抗体的阳性率为80.0%,在其它风湿病人中的阳性率为7.0%,抗CCP抗体对RA的敏感性和特异性分别为80.0%、96.0%,其敏感性高于RF,但差异无统计学意义（P〉0.05）,特异性明显高于RF（P〈0.05）。联合应用抗CCP抗体与RF进行诊断,二者均阳性时敏感性为65.0%,特异性为97.3%。抗CCP抗体与RF实验结果之间无相关性。结论抗CCP抗体对RA具有较好的敏感性和很高的特异性,可与RF相互补充,联合检测可提高对RA早期诊断的准确性。     

The Role of Anti-Cyclic Cytrullinate Antibodies Testing in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, progressive inflammatory disease, which leads to joint destruction and deformity and is often accompanied by systemic complications. It is generally considered an autoimmune disease characterized by several autoantibodies. The impressive advances made in understanding the biological mechanisms of RA have led to more focused, directed therapies that have joined, and in many cases overcome, more traditional treatments. Along the last decade, the so-called biological anti-TNF-alpha agents have been shown to reduce disease activity, to slow disease progression and to improve patients’ quality of life. The clear evidence that an early therapeutic intervention improves the overall outcome of the disease supports the importance of an early diagnosis. In the last years, several studies showed that anti-cyclic citrullinated peptide antibodies (anti-CCP) represent a sensitive and specific serologic marker for RA. Moreover, a large body of evidence has shown that anti-CCP may also serve as an early diagnostic and prognostic marker in RA. The aim of this article is to provide an overview of the current state of knowledge regarding anti-CCP focusing in particular on their clinical specificity and prognostic value in RA.     

Anti-cyclic Citrullinated Peptide Antibodies are Highly Associated with Severe Bone Lesions in Rheumatoid Arthritis Anti-CCP and Bone Damage in RA

In the present study we investigated the predictive value of anti-cyclic citrullinated peptide antibodies (anti-CCP) in early rheumatoid arthritis (RA) with respect to the bone damage.

Fifty-four patients with early RA (onset <12 months), 35 classified as established RA (onset >12 months), 33 healthy donors and 76 non-RA autoimmune diseases, were enrolled. Anti-CCP and IgG, IgA, IgM rheumatoid factors (RFs) were determined at baseline. Disease activity score (DAS 28) was calculated at the entry. Bone involvement was evaluated by X-rays and sonography.

The specificity of anti-CCP was 98.4%; significantly (?p<0.01) higher than those of the IgM- (86.0%), IgA- (86.0%) and IgG-RFs (66.2%), respectively. Anti-CCP were detected in 23/54 (42.6%) early RA patients and in 16/35 (45.7%) established RA patients. In the early RA group, 6/33 (18.2%) of the patients without bone lesions, 12/16 (75%) with juxta-articular osteoporosis (JO) and 5/5 with joint erosions (JE) resulted positive showing a significant (?p<0.001) difference between the groups without and with radiological damage.

In the established RA group a significant (?p<0.01) difference being between the group without radiological damage and that with JE was found. Finally, in patients without radiological lesions, examined by ultrasound, anti-CCP antibodies were detected only in subjects with pathologic findings (31.25%).

Data here reported confirm that the presence of anti-CCP are specific for diagnosis of RA, of recent onset also and they are potentially useful as prognostic index of bone involvement.     

IgE Anti-IgG Antibodies in Patients with Juvenile and Adult Rheumatoid Arthritis Including Felty's Syndrome

Anti-IgG; antihodies (anti-IgG) of the IgE class were studied in sera from patients with juvenile rheumatoid arthritis (JRA). rheumatoid arthritis (RA) and patients with Felty's syndrome (FS) by use of an indirect immunofluorescence technique. Forty-two percent of 26 patients with JRA had IgE anti-IgG in serum all in low titers. Positive reactions prevailed in patients with multiple joint involvement. Sixty-three percent of 30 patients with RA and 80% of 20 patients with FS had IgE anti-IgG, the titers found in FS patients being significantly higher. In JRA and FS patients the IgE anti-IgG titers were correlated to the titers of anti-IgG of the IgG class, and for FS patients also with the IgM and IgA classes of anti-IgG. In six of 10 patients with RA the synovial fluid samples from both knees contained IgE anti-IgG. In four of these patients the titers of IgE anti-IgG were higher than in the corresponding serum sample, pointing to a local production. After G-200 Sephadex chromatography IgE anti-IgG were demonstrated in the void volume indicating the presence of these autoantibodies in immune complexes. IgE anti-IgG may be involved in the pathogenesis of JRA and RA by eliciting Type I and III reactions.     

抗GPI抗体和抗CCP抗体对RA诊断价值的比较分析

目的:评价抗环瓜氨酸肽(CCP)抗体和抗葡萄糖-6-磷酸异构酶(GPI)抗体对类风湿关节炎(RA)的诊断价值.方法:用酶联免疫吸附试验(ELISA)分别测定RA患者42例、其他风湿病患者32例以及健康对照者30例血清中的抗CCP抗体和抗GPI抗体,并应用R0C曲线比较两者对RA的诊断价值.结果:RA组血清抗CCP抗体水...     

微粒子酶免疫化学发光法和ELISA定量检测CCP抗体的临床应用评价

目的:应用化学发光法、酶联免疫吸附试验(ELISA)定量检测类风湿性关节炎(RA)患者抗环瓜氨酸多肽(CCP)抗体的含量,探讨CCP抗体在RA早期诊断和治疗中的作用.方法:选取69例RA、30例强直性脊柱炎(AS)、33例干燥综合征(SS)患者、61例健康体检人群,分别用化学发光、ELISA检测其血清CCP抗体的含量....     

Plasma TNF-Binding Capacity and Soluble TNF Receptors in Patients with Juvenile Idiopathic Arthritis

Background:  Unbalanced production of proinflammatory cytokines may be related to disease progression in rheumatoid arthritis and juvenile idiopathic arthritis (JIA). Within the TNF system, the two agonists, TNF-α and TNF-β, also called lymphotoxin-α (LT), are bound by soluble TNF receptors (sTNFR-I and -II) that act as natural inhibitors of TNF-induced inflammation. We investigated the plasma levels of sTNFR-I in parallel with LT-binding capacity (LTBC) in patients with JIA.
Methods:  The levels of sTNFR-I were measured by ELISA (R&D). LTBC was determined by spiking diluted plasma samples with recombinant LT. Detectable LT was measured by an in-house ELISA measuring unbound LT only. LTBC was expressed in arbitrary units (AUs) as the percentage value of bound LT to added LT.
Result:  In contrast to previous findings of elevated sTNFR levels in patients with various chronic inflammatory diseases, we found slightly reduced sTNFR-I levels in JIA patients ( n  = 123) compared with age-matched healthy controls ( n  = 37): 1077 pg/ml (819–2280) versus 1185 pg/ml (625–2303) [median (range)], P  = 0015. However, the sTNFR-I levels correlated positively with the number of active joints, physicians' global assessment and CRP. In contrast, patient LTBC values were elevated compared to healthy controls: 44 AU (36–52) versus 31 AU (13–41), P  < 0.0001.
Conclusion:  Despite overall slightly reduced plasma levels of sTNFR-I, the capacity to bind TNF was increased in plasma samples from JIA patients. Studies to identify the TNF-binding substances in plasma are in progress.     

Anti‐Citrullinated Peptide Antibodies in Sudanese Patients with Leishmania donovani Infection Exhibit Reactivity not Dependent on Citrullination

African patients with Leishmania donovani infections have signs of strong systemic inflammation and high levels of circulating immune complexes (IC) and rheumatoid factor (RF), all serologic markers of rheumatic disease. As inflammation in general is associated with citrullination, we sought to investigate ACPA responses in Sudanese Leishmania patients. Serum samples were collected from Sudanese patients with visceral leishmaniasis (VL) and post‐kala‐azar dermal leishmaniasis (PKDL) as well as from ACPA‐positive Sudanese rheumatoid arthritis patients and compared to healthy Sudanese controls. Levels of circulating C1q‐binding IC and anticyclic citrullinated peptide 2(CCP2) were investigated using ELISA, and RF was measured with nephelometry. C1q adsorption was carried out to investigate anti‐CCP2 content in IC. Citrulline specificity was evaluated with control plates with cyclic arginine‐containing control peptides. Leishmania‐infected patients had elevated levels of RF and circulating IC but also a significant increase in anti‐CCP2 (12%) as compared to healthy controls. Anti‐CCP2‐positive Leishmania patients displayed lower anti‐CCP2 levels than Sudanese patients with rheumatoid arthritis (RA), and anti‐CCP2 levels in Leishmania patients showed a continuum not resembling the dichotomous pattern seen in patients with RA. Whereas the anti‐CCP reactivity of Sudanese RA sera was strictly citrulline dependent, anti‐CCP2‐positive Leishmania sera reacted equally well with ELISA plates containing arginine control peptides. There was a strong correlation between anti‐CCP2 and circulating IC among the Leishmania patients, but IC depletion only marginally diminished anti‐CCP2 levels. Our findings stress the importance to interpret a positive CCP test carefully when evaluated in non‐rheumatic conditions associated with macrophage activation.     

抗CCP抗体和RF联检在RA诊疗中的临床价值

目的：研究抗环瓜氨酸肽（anti-cyclic citrullinated peptide,Anti-CCP）（抗CCP抗体）和RF的检测在类风湿关节炎（RA）诊疗中的临床价值。方法：分别用酶联免疫吸附试验（ELISA）、BeckMan全自动蛋白分析仪同时检测早期RA组（病程〈1年）42例,RA组（病程〉1年）40例,非RA对照组40例患者血清抗CCP抗体和RF。结果：早期RA组、RA组的抗CCP抗体、RF阳性率显著高于非RA对照组（P〈0.05）RA组抗CCP水平显著高于早期RA组（P〈0.01）,两者RF无显著差别（P〉0.05）。RA组与早期RA组CCP抗体与RF二者无相关性。结论：联检抗CCP抗体、RF有助于类风湿的早期诊断和预测病情的进展。     

Anti-IgG Antibodies and Antinuclear Antibodies in Allergic Patients

With an indirect immunofluorescencc technique 77 % of 96 patients with type I allergy and 40% of 20 patients with intrinsic bronchial asthma showed positive reactions for IgG ami-IgG antibodies in serum. They were present partly in an aggregated state not directly detectable before treatment with dithiothreitol. The aggregates could be removed by precipitation with polyethylene glycol. The IgG ami-IgG in hyposensitized patients were directed against both F(ab')² and Fe fragments of rabbit IgG. Thirty of the type I allergic patients were examined once during hyposensitization as well. Before treatment 87% and IgG anti-IgG (titres 9–72). After ≥ 13 months of treatment 100% were positive (titres 35–288), Fight patterns were also examined after hyposensitzation had been discontinued for at least 12 months. The titres of IgG ami-IgG had then reverted lo the levels obtained before hyposensitization. Of 116 controls matched for sex and age, 79r had IgG ami-IgG anybodies, is suggested that the production of IgG anti-IgG may be stimulated by the presence of immune complexes and that purity, amount and/or combination of allergens administered during hyposensitization may influence the production of anti-JgG antibodies. Neither IgK anti-IgG nor antinuclear antibodies seem to be of particular significance in allergic patients.     

Antiphospholipid Antibodies in Patients With Preeclampsia

PROBLEM: To determine the incidence of anticardiolipin and antiphosphatidylserine antibodies in women with preeclampsia. METHODS: Sera from 100 women with preeclampsia and 100 normotensive pregnant women in the third trimester were assayed for anticardiolipin and antiphosphatidylserine antibodies. RESULTS: Antiphosphatidylserine antibodies were positive for IgM in 1 patient (1%) and for IgG in 4 patients (4%). IgM antibodies to cardiolipin were positive in two patients (2%) while IgG antibodies to cardiolipin were positive in nine patients (9%). Only 3% of the control women were positive for antiphospholipid antibodies. None of the patients or controls had positive levels of IgA anticardiolipin or antiphosphatidylserine antibodies. CONCLUSIONS: Elevated levels of IgG or IgM antibodies to cardiolipin and phosphatidylserine were detected in 11/100 (11%) of women diagnosed with preeclampsia in the third trimester compared to only 3/100 (3%) positive in controls (P < 0.05). These findings suggest that antiphospholipid antibodies may play a pathogenic role in some women with preeclampsia.     

血清抗环瓜氨酸肽抗体与类风湿关节炎合并肺间质纤维化的相关性分析

分析类风湿关节炎(rheumatoid arthritis,RA)患者血清中抗环瓜氨酸肽(CCP)抗体水平与类风湿关节炎患者合并肺间质纤维化的关系.选取RA患者87例,其中合并肺间质纤维化(IPF)22例,单纯RA45例,采用酶联免疫吸附实验(ELISA)检测血清抗CCP抗体滴度,免疫比浊法检测类风湿因子(RF)滴度,...