Occurrence of two germline-related rheumatoid factor idiotypes in rheumatoid arthritis and in non-rheumatoid seropositive individuals.

Human rheumatoid factor (RF) paraproteins express two distinct light chain cross-reactive idiotypes defined by the monoclonal antibodies 17.109 and 6B6.6. These germline gene-related cross-reactive idiotypes are both carried on VK3 light chains and are each present on about one-third of IgM RF paraproteins. We assessed the degree to which these idiotypes are represented in polyclonal RFs. We used rheumatoid arthritis (RA) and non-RA RF-positive sera selected from a large cross-sectional population study (the Mini-Finland Health Survey), and sera from a community-based follow-up study of recent-onset RA patients from Heinola, Finland. In the Mini-Finland Health Survey, elevated levels of the 17.109 RF idiotype were seen in sera of 13% of the RA and 19% of the non-RA group; 6B6.6 RF was seen in 26% of the RA and 28% of the non-RA group. In sera of the Heinola follow-up study, 17.109 RF was seen in 12% initially, but in only 3% at 8 years. Similarly, 6B6.6 RF was detected in 25% initially, but in only 7% at 8 years. Ten sera positive for RF prior to the onset of clinical RA were identified from individuals of a second large population study from Finland (North Karelia project); two of these sera exhibited the 6B6.6 idiotype; none exhibited the 17.109 idiotype. The data are consistent with the concept that these germline gene-related cross-reactive RF idiotypes occur frequently in the polyclonal RF of non-RA as well as RA sera, and that in RA the idiotypes may sometimes be reduced or lost as a consequence of somatic diversification of the RF through somatic mutation, usage of new germline genes, or both.     

Complement activating properties of complexes containing rheumatoid factor in synovial fluids and sera from patients with rheumatoid arthritis.

The relationship between complexes containing rheumatoid factor and complexes activating complement was examined in synovial fluids and sera from patients with rheumatoid arthritis (RA). In each case this was performed by quantifying the amount of rheumatoid factor bound by solid phase Fab'2 anti-C3 and/or solid phase conglutinin. Both anti-C3 coated and conglutinin coated microtitre plates bound high levels of complexes containing rheumatoid factor from sera of RA patients with vasculitis. Unexpectedly, these complexes were detected in synovial fluids from only a minority of RA patients with synovitis. However, RA synovial fluids did contain other complexes as shown by the presence of complement consuming activity, C1q binding material and immunoglobulin attaching to conglutinin. It is considered that in RA synovial fluids the complexes containing RF and those activating complement are not necessarily the same whilst in vasculitic sera the complexes containing rheumatoid factor also activate complement.     

Topics on immunological tests for rheumatoid arthritis

To prevent joint destruction, it is important to diagnose RA early and to speculate the prognosis. Several new laboratory tests have been developed for this purpose. In addition to rheumatoid factor (RF), IgG-RF, anti-agalactosyl IgG antibodies (CARF), and matrix metalloproteinase 3 (MMP-3) have become available as diagnostic tests for RA. Among them, anti-cyclic citrullinated peptide antibodies (anti-CCP antibodies) have the sensitivity and specificity of 81.0% and 92.4%, respectively, which are superior to other laboratory tests by ROC analysis. Moreover, the specificity of anti-CCP antibodies to diagnose early RA was much higher than that of RF, although the sensitivity of CARF was slightly high compared with that of RF. In contrast, MMP-3 is thought to be an evaluative test for the activity of RA because a significant correlation was found between MMP-3 and CRP, but MMP-3 has a possibility as a prognostic test to know the joint damage of RA. We have shown that the progression of joint damage (Sharp score) was faster in MMP-3-positive patients than negative patients. Anti-CCP antibodies was also reported to associate with the progression of joint damage and may be used also as a prognostic test. We next examined how efficiently was the diagnosis of RA made by combining these laboratory tests. Although anti-CCP antibodies are highly specific to RA, the specificity of RF was not so high but became up to 92% when combined with MMP-3. In order to diagnose RA efficiently, we may firstly examine RF, next MMP-3 if RF is positive, and anti-CCP antibodies if RF is negative.     

Fc gamma R expression on NK cells influences disease severity in rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with autoantibodies, the best known of which is rheumatoid factor (RF). RF/IgG complexes interact with FcgammaR on the surface of neutrophils, NK cells and monocyte/macrophages. We have analyzed the expression pattern and allelic polymorphisms of three FcgammaR genes (FcgammaRIIA, FcgammaRIIC and FcgammaRIIIA) in a large sample of RA patients and normal donors. We have found that the level of FcgammaR (CD16 and CD32) expression on NK cells is lower in RA patients than in normal individuals. Genotypic analysis demonstrated that the CD32 isoform expressed by the majority of RA patients was not the activating FcgammaRIIc1 isoform, commonly seen in normal individuals, but rather the inhibitory FcgammaRIIb isoform. The combination of the FcgammaRIIIA-176F allele with a lack of CD32 expression in NK cells appeared to be characteristic of RA subjects with aggressive disease. Since FcgammaRII and FcgammaRIIIA are predominantly expressed by NK cells, these data further suggest that FcgammaR-mediated activation of NK cells could be a disease-determining factor in RA patients.     

A Morphological and Immunohistochemical Study of Lymphoid Germinal Centers in Synovial and Lymph Node Tissues from Rheumatoid Arthritis Patients with Special Reference to Complement Components and Their Receptors

Rheumatoid arthritis (RA) is one of the immune complex (IC) diseases in which lymphoid germinal centers (GCs) are found in the synovial tissue. Simultaneously, patients with RA often show swelling of lymph nodes. The morphology and function of the lymph node GCs in patients with RA is not clear. The aim of this study was to evaluate the differences in morphology and immunoreactions to complement (C) components, their receptors, and lgM-rheumatoid factor (RF) between synovial GCs and lymph-node GCs in RA. Furthermore, the relationship between these immuno-reactive substances and follicular dendritic cells (FDCs) in GCs was investigated. The tissues examined were 41 RA synovial specimens, seven RA lymph nodes with massive lymphadenopathy, and 10 non-RA lymph nodes. The number of synovial GCs was relatively decreased in comparison with lymph-node GCs in RA, and the diameter of each synovial GC was smaller than that of each lymph-node GC. The synovial GCs were edematous and less cellular, and moreover, those from RF-seronegative cases were smaller than those from RF seropositive cases. On the other hand, the lymph-node GCs in RA were larger, more cellular and hyperplastic, but contained more tingible-body macro-phages (TBMs) and neutrophils. In the GCs of both synovial tissues and lymph nodes in RA, early C components (C1q, C4, C3c, C3d), IgM RF, and C3b receptor (C3bR) and C3d receptor (C3dR) were expressed as a lacy network by light microscopy, and were demonstrated on the surfaces of FDCs and lymphocytes, and in the intercellular spaces by electron microscopy. Furthermore, immuno-staining for dendritic reticulum cells (DRC, DAKO DRC1) was observed in a lacy pattern by light microscopy and on the cell surface of FDCs by electron microscopy. In the GCs of non-RA lymph nodes, early C components, C3bR, C3dR, and DRC showed a similar reaction pattern, but IgMRF did not. Consequently, no marked difference in immunoreactions in the GCs, except for the immunoreactions of late C components, was found between synovial tissues and lymph nodes in RA. On the basis of these findings, we discuss the possibility of the presence of a RF-IC.     

A morphological and immunohistochemical study of lymphoid germinal centers in synovial and lymph node tissues from rheumatoid arthritis patients with special reference to complement components and their receptors

Rheumatoid arthritis (RA) is one of the immune complex (IC) diseases in which lymphoid germinal centers (GCs) are found in the synovial tissue. Simultaneously, patients with RA often show swelling of lymph nodes. The morphology and function of the lymph-node GCs in patients with RA is not clear. The aim of this study was to evaluate the differences in morphology and immunoreactions to complement (C) components, their receptors, and IgM-rheumatoid factor (RF) between synovial GCs and lymph-node GCs in RA. Furthermore, the relationship between these immunoreactive substances and follicular dendritic cells (FDCs) in GCs was investigated. The tissues examined were 41 RA synovial specimens, seven RA lymph nodes with massive lymphadenopathy, and 10 non-RA lymph nodes. The number of synovial GCs was relatively decreased in comparison with lymph-node GCs in RA, and the diameter of each synovial GC was smaller than that of each lymph-node GC. The synovial GCs were edematous and less cellular, and moreover, those from RF-seronegative cases were smaller than those from RF-seropositive cases. On the other hand, the lymph-node GCs in RA were larger, more cellular and hyperplastic, but contained more tingible-body macrophages (TBMs) and neutrophils. In the GCs of both synovial tissues and lymph nodes in RA, early C components (C1q, C4, C3c, C3d), IgM-RF, and C3b receptor (C3bR) and C3d receptor (C3dR) were expressed as a lacy network by light microscopy, and were demonstrated on the surfaces of FDCs and lymphocytes, and in the intercellular spaces by electron microscopy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Human monoclonal rheumatoid factors derived from the polyclonal repertoire of rheumatoid synovial tissue: incidence of cross-reactive idiotopes and expression of VH and V kappa subgroups.

A panel of 14 human monoclonal and monoreactive IgM rheumatoid factors (RF) derived from the synovial tissue of rheumatoid arthritis (RA) patients was studied for the expression of cross-reactive idiotopes (CRI) and variable heavy (VH) and variable kappa (V kappa) subgroups. Four of the twelve kappa RF expressed light chains of the V kappa III subgroup. Three of these were characterized as belonging to the V kappa IIIb sub-subgroup, and expressed the V kappa IIIb associated CRI, 17.109. None of the RF expressed the V kappa IIIa-associated CRI, 6B6.6. One of the fourteen RF expressed the VH-associated CRI, G6, and five expressed either or both the VHIII-associated CRI, B6 and D12. Seven RF bound to protein A (SpA), which indicates the expression of VHIII subgroup V regions. Together the data indicated that 9/11 RF express VHIII regions and 2/11 express VHI regions. There was no obvious correlation between V region usage or CRI expression and fine specificity of the RF for human IgG subclasses. These data indicate a difference in V gene usage by RF derived from RA patients compared with RF paraproteins derived from non-RA patients. There is not a bias towards variable chains of the V kappa III subgroup, but a marked preference for variable heavy chains of the VHIII subgroup is seen. Further studies may elucidate the pathological significance of these findings in RA.     

A basic study of determination matrix metalloproteinase-3 and carbohydrate in rheumatoid factor in serum for diagnosis of rheumatoid arthritis

The examination of rheumatoid factor (RF), one of the diagnostic marker of rheumatoid arthritis (RA), showed negative about 25% of patients with RA. We analyzed a matrix metalloproteinase-3 (MMP-3) and a carbohydrate in rheumatoid factor (CA.RF) for diagnosis of RA: the former is used the kit "Panaclear MMP-3[Plate]" and the latter is used the kit "Picolumi CA.RF". The basic study of these reagents showed satisfactory results. In 73.3% of seronegative RA showed positive on both MMP-3 and CA.RF levels in serum, respectively. We found that these examinations might be useful for diagnosis of RA, especially during seronegative RA.     

New biomarkers for rheumatoid arthritis

Rheumatoid factor (RF) has been commonly used as a biomarker of rheumatoid arthritis (RA). It is important to diagnose RA early and to prevent joint destruction before irreversible damage occurs. For this purpose, several new biomarkers, such as anti-cyclic citrullinated peptide antibody (anti-CCP) and matrix metalloproteinase-3 (MMP-3), have become available for both the diagnosis and prognosis of RA. RF showed a tolerable sensitivity of 68.5% for RA, but low specificity of 77.1% for patients with other rheumatic diseases. Anti-agalactosyl IgG antibodies (CARF) showed a slightly higher sensitivity of 73.9%, but specificity as low as that for RF. In contrast, anti-CCP demonstrated high sensitivity of 76.1% and marked specificity of 92.4% for patients with other rheumatic diseases. Anti-CCP was significantly superior to other biomarkers on receiver-operating characteristic curve (ROC) analysis. Moreover, meta-analysis revealed that the pooled sensitivity and specificity were 67% and 95% for anti-CCP, and 69% and 85% for RF, respectively, and that anti-CCP was more specific than RF for diagnosing RA. On the other hand, MMP-3 has been suggested to be a prognostic biomarker as well as an evaluative biomarker for RA. We next examined if the diagnostic accuracy of early RA is improved by combining these biomarkers. The specificity of RF was not as high as anti-CCP but rose to 92% when combined with MMP-3. Thus, we concluded that anti-CCP is superior to other biomarkers in terms of diagnostic accuracy, and that these combined assays are useful in the early diagnosis of RA.     

Diagnostic value and clinical significance of anti-CCP in patients with advanced rheumatoid arthritis

OBJECTIVES: To investigate the prevalence of anticyclic citrullinated peptide (anti-CCP) in patients with advanced rheumatoid arthritis (RA) and to compare it with those in control subjects. Further, to study the relation between the anti-CCP and the disease activity parameters in these patients. PATIENTS AND METHODS: Seventy-six RA patients who had a mean disease duration of 9.8 years were included. Eighty-three age-matched non-RA volunteers were enrolled as the control group. Disease duration, duration of morning stiffness, swollen and tender joint counts, hand deformity, patient's assessment of pain, anti-CCP, rheumatoid factor (RF) and acute phase proteins were evaluated. The functional disability was also assessed with the Modified Health Assessment Questionnaire (HAQ). RESULTS: Thirty-seven sera (48.7%) in the patient group and one serum (1.2%) in the control group were positive for anti-CCP. RF was positive in 45% of the RA cases and in 5% of controls. Sensitivity and specificity of anti-CCP reactivity for RA were 49.0% and 99.0%, respectively. HAQ score and duration of morning stiffness were found to be significantly associated with anti-CCP positivity. Disease duration, swollen joint count and anti-CCP positivity were the most important variables predicting hand deformity. CONCLUSION: The prevalence, sensitivity and specificity of anti-CCP in patients with advanced RA were found to be similar to those reported in patients with early disease. Anti-CCP was significantly associated with some parameters of both disease activity and severity. Anti-CCP might be a useful parameter in clinical evaluation of patients with advanced RA.     

The distinct subgroup of patients with rheumatoid arthritis shown by Ig G3-reactive rheumatoid factor

The reactivity of rheumatoid factor (RF) with immunoglobulins of the IgG3 subclass was examined in 49 patients with rheumatoid arthritis (RA) using two types of IgG3 myeloma (routine and IgG3m-15 allotype). Among 49 patients, serum from eight cases showed positive reactivity with both types of IgG3 myeloma by radio-immunoassay (RIA). The isotype of IgG3-reactive RF was not specific; it belonged to the IgM class as well as the IgG subclasses IgG1, IgG2 and IgG4. The patients with IgG3-reactive RF belonged to the clinically-severe classification of RA, having a high erythrocyte sedimentation rate (ESR), high titre in the RA hemagglutination (RAHA) test, and above all they had low levels of complement. Generally, it is concluded that patients with IgG3-reactive RF have serious arthritis and that IgG3-reactive RF might play an important role in the inflammatory process. Furthermore, it was also shown that the RF-reactive site was not associated with the protein-A binding site of IgG3, since RF reacting with IgG3m-15 reacted similarly with routine IgG3, regardless of the difference of the protein-A binding activity. This was confirmed by adding protein-A to the reaction of RF and IgG3m-15 which binds with protein-A. This suggests that the actual reactive site of RF is different to the site that binds protein-A.     

Association of rheumatoid factor production with FcgammaRIIIa polymorphism in Taiwanese rheumatoid arthritis

Fcgamma receptors (FcgammaR) impact upon the development of inflammatory arthritis through immune complex stimulation and proinflammatory cytokine production. FcgammaRIIa, FcgammaRIotaIotaIotaa and FcRgammaIIIb polymorphisms were genotyped in 212 rheumatoid arthritis (RA) patients and 371 healthy control subjects using an allelic-specific polymerase chain reaction (PCR). No significant skewing in the distribution of FcgammaRIIa H/R131, FcgammaRIIIa F/V158 and FcgammaRIIIb NA1/NA2 was found between RA patients and healthy control subjects. However, a significant skewing distribution of the FcgammaRIIIa F/V158 polymorphism was observed between rheumatoid factor (RF)-positive versus RF-negative RA patients (P = 0.01). The low-affinity FcgammaRIIIa F158 allele seems to have a protective role in RF production, in comparison with the FcgammaRIIIa V158 allele (P = 0.004; OR = 0.485; 95% CI: 0.293-0.803). A high frequency of FcgammaRIIIa F/F158 was identified in RA patients with negative RF compared with RF-positive patients (for FF158 versus FV158 + VV158; P = 0.002; OR = 0.372; 95% CI: 0.194-0.713). In addition, no association was found between FcgammaRIIa H/R131, FcgammaRhoIIIa F/V158 and FcgammaRIIIb NA1/NA2 polymorphisms and other clinical parameters. The results of this study suggest that three activating FcgammaRs polymorphisms lack association with RA but FcgammaIIIa F/V158 polymorphism may influence RF production and IgG RF immune complex handling in Taiwanese RA patients.     

New diagnostic and evaluative tests for rheumatoid arthritis

To prevent joint destruction, it is important to diagnose RA early and to consider the prognosis. For this purpose, several new laboratory tests, such as IgG-RF, anti-agalactosyl IgG antibodies (CARF), and matrix metalloproteinase-3 (MMP-3), have become available for diagnosing RA. RF has a tolerable sensitivity of 68.5% for RA, but low specificity of 77.1%, and also 76.0% for patients with other rheumatic diseases and chronic inflammatory disease, respectively. CARF showed slightly higher sensitivity but low specificity for other rheumatic diseases and chronic inflammatory patients. In contrast, anti-cyclic citrullinated peptide antibody (anti-CCP), a new diagnostic test for RA, demonstrated significantly high specificity for other rheumatic diseases, and also for chronic inflammatory disease patients. Anti-CCP was superior to other laboratory tests by ROC analysis. Moreover, both CARF and anti-CCP had higher sensitivity of 66.7%, 61.5%, respectively, for the diagnosis of early RA than RF. On the other hand, MMP-3 is thought to be not only an evaluative test for the activity of RA because of its significant correlation with CRP, but also has potential as a prognostic test to identify joint damage from RA. Anti-CCP was also reported to associate with the progression of joint damage and may be also used as a prognostic test. We next examined the efficiency of RA diagnosis made by combining these laboratory tests. The specificity of RF was not as high as anti-CCP but reached 92% when combined with MMP-3. Thus, it is concluded that anti-CCP is superior to other laboratory tests in sensitivity and specificity, and that these combination assays are useful in the early diagnosis of RA.     

A study of rubella haemagglutination inhibition antibodies in rheumatoid arthritis

In the literature there are speculations concerning a possible role of Rubella virus in the etiopathogenesis of rheumatoid arthritis (RA). Rubella haemagglutination inhibition (RHI) antibody titres were determined in sera from thirty-six pairs of patients with RA and diseases unrelated to RA, matched for age and sex. Latex flocculation tests (LFT) were performed in both groups, as well. Mean ranks (log₂) of RHI test for the RA and non-RA groups were almost identical (5·75 and 5·94, respectively). Titre of RHI was unrelated to the presence or absence, or titre, of LFT. Thus, no evidence of continuing Rubella virus infection can be found in patients with RA by this antibody test. The possibility that the aetiology of RA may be related to some viral infection is nevertheless of continuing interest.     

Correlative studies of rheumatoid factors and anti-viral antibodies in patients with rheumatoid arthritis.

An analysis of the relationship between the immune response to ubiquitous herpes family viruses, namely Epstein-Barr virus (EBV), cytomegalovirus (CMV), and varicella-zoster virus (VZV) and the presence of rheumatoid factors (RF), which are autoantibodies characteristic of patients with rheumatoid arthritis (RA), was conducted. Antibody profiles (RF, anti-viral antibodies) were monitored in the serum of the RA patients, and in normal individuals. No patient was found to have circulating RF in the absence of anti-viral antibodies. When the patients and normal controls were subdivided according to the presence of serum RF, it was found that when RF were present, the frequency of anti-CMV antibodies, but not anti-EBV or anti-VZV antibodies, was significantly higher (P = 0.02) when compared with RF-negative individuals. The titres of anti-CMV but not anti-VZV antibodies were found to increase in the RA patients with disease duration. To see if these viruses could stimulate RF production in vitro, peripheral blood mononuclear cells (PBMC) isolated from the patients and normal controls were stimulated with viral antigens. PBMC from normal controls, but not from RA patients, appeared to be responsive to viral antigen stimulation and produced RF. These data suggest that the immune response to CMV, to a greater extent than to EBV or VZV, correlates with the presence of RF.     

Abnormalities in the glycosylation of IgG in spouses of patients with rheumatoid arthritis. A family study.

Forty-seven members of eight families with a rheumatoid proband were analysed for abnormal glycosylation of IgG. The results (%G(o) which is the percentage of oligosaccharide chains lacking galactose) were corrected for age and expressed as SD units about the mean for the normal population. Seven of 8 probands, 3/8 spouses, 3/5 RA relatives and 4/26 non-RA relatives had %G(o) values greater than 1SD above the age corrected mean for the normal control population (P less than 0.001, less than 0.01, less than 0.005 and greater than 0.5 respectively). A further 13 spouse pairs were studied. Ten of 13 probands and 8/13 spouses had %G(o) values greater than 1SD above the mean (P less than 0.001 and less than 0.001 respectively). Thus in total, a strikingly high number of unaffected spouses had high %G(o) values (11/21). IgM, IgA and IgG rheumatoid factors were studied. While RA patients' sera showed a correlation between IgM and IgA rheumatoid factors and %G(o), (IgM, r = 0.41 0.05 greater than P greater than 0.02, IgA, r = 0.36, P = 0.05), no correlation between IgG RF and %G(o) was noted in the RA patients. No correlation was found between any of the RF classes and %G(o) in spouses and non-RA relatives.     

Differences in mutational patterns between rheumatoid factors in health and disease are related to variable heavy chain family and germ-line gene usage

The sequences of the heavy chain variable (V_H) segment and dissociation constants (K_d) of 14 IgM rheumatoid factors (RF) derived from 11 different germ-line gene segments from five healthy immunized donors (HID) are described. We extend a previous analysis of two clones from one donor using only the germ-line segment DP-10. In the present study, the mutation patterns of these new RF and the two earlier reported HID RF clones are analyzed in relation to V_H family, germ-line origin, and K_d. The panel of HID RF is further compared with 33 previously described IgM RF from patients with rheumatoid arthritis (RA). There is a high rate of mutation in the panel of HID RF (mean of ten mutations/V_H). RF originating in RA patients have a comparable mutation rate (mean of 11 mutations/V_H), suggesting that hypermutation of IgM RF is not disease related. The HID RF have, however, a significantly lower affinity for IgG than the RA RF. We found that the structural basis of the differences between HID and RA RF is related to V_H family usage. RF of the V_H1 family use very similar germ-line genes in HID and RA patients. HID RF of the V_H1 family have, however, a low ratio of replacement-to-silent (R : S) mutations of only 0.41 in the heavy chain complementarity region (CDR_H) 1 and 2. This is statistically significantly lower than the corresponding ratio of 3.14 in the V_H1 RA RF. In contrast, RF of the V_H3 family from HID and RA patients have very similar R : S ratios of 1.75 and 1.71 in CDR_H1 and 2, respectively. The V_H3 RA RF are, however, predominantly encoded by genes not encoding any HID RF. Thus, both repertoire differences and hypermutation resulting in significantly lower R : S ratios can be observed in RF from HID compared with RA RF.     

抗突变型瓜氨酸波形蛋白检测在类风湿关节炎中的意义

目的：评价抗突变型瓜氨酸波形蛋白（抗MCV）在类风湿关节炎（RA）诊断中的价值。方法：检测225例RA患者、77例其他关节炎患者以及80例正常对照血清中抗MCV、抗CCP和RF-IgM的水平,比较抗MCV、RF-IgM、抗CCP及抗MCV和抗CCP联合检测在类风湿关节炎的诊断中的意义。结果：①抗MCV、RF-IgM、抗CCP敏感性和特异性分别为74.67%、91.71%；77.78%、91.71%；65.33%、94.27%,抗MCV与抗CCP联合检测可明显提高诊断特异性,对RA诊断的敏感性和特异性分别为60.89%、99.36%；②抗MCV与抗CCP检测对RF阴性RA病例的诊断有一定价值（30%,26%）；③抗MCV、抗CCP与RF-IgM之间均显著相关（P〈0.01）；④抗MCV与年龄、病程、功能分级、压痛关节数、ESR、CRP、X线分期及晨僵持续时间存在相关（P〈0.01或P〈0.05）,而与性别、双手平均握力和肿胀关节数无关（P〉0.05）。结论：抗MCV对RA有较高的诊断价值,抗CCP和抗MCV联合检测对RA有高度特异性,抗MCV能一定程度反映RA的临床病情,可作为RA的血清学指标。     

IgG rheumatoid factors and anti-nuclear antibodies in rheumatoid vasculitis.

We studied the distribution and characteristics of circulating rheumatoid factors (RF) and anti-nuclear antibodies (ANA) in 30 rheumatoid arthritis (RA) patients who had polyarthritis alone (group I), 28 RA patients with polyarthritis and extra-articular disease (group II), 28 RA patients with systemic vasculitis (group III) and 60 healthy matched controls. IgG RF occurred more frequently and in higher serum titres in group III (100%) than RA patients in group I (40%), or in group II (18%) or in normal controls (5.8%). The serum titre of IgM RF was higher in vasculitis patients than in other RA patients. ANA were found in 74% of all RA patients and although the frequency did not differ in the three patient groups, the serum titre was significantly higher in the vasculitis group. Antibodies to extractable nuclear antigen were found only in group III (18.7%). Antibodies to histones were also more prevalent in group III than in the other RA groups. The serological abnormalities in rheumatoid vasculitis differed quantitatively as well as qualitatively from other RA patients.     

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。