"Atypical p-ANCA" in IBD and hepatobiliary disorders react with a 50-kilodalton nuclear envelope protein of neutrophils and myeloid cell lines

BACKGROUND & AIMS: Atypical "antineutrophil cytoplasmic antibodies" (ANCA) are present in patients with ulcerative colitis (UC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH). Recently, we showed that atypical p-ANCA react with nuclear envelope proteins of neutrophils. Based on this observation, we aimed to characterize the nuclear antigen recognized by atypical p-ANCA. METHODS: We prepared cytoplasmic and nuclear extracts of human neutrophils, human HL-60, and murine 32D myeloid cells. Proteins were resolved by 1- and 2-dimensional gel electrophoresis. Reactive proteins were detected by immunoblotting with sera from 118 individuals (UC, 25; PSC, 28; AIH, 35; disease and normal controls, 30). Atypical p-ANCA (n = 64) were affinity-purified against the reactive protein and investigated for their immunofluorescence pattern using confocal microscopy. RESULTS: Immunoblotting showed reactivity to a myeloid-specific 50-kilodalton nuclear protein with an isoelectric point of pH 6.0 detected in 92% (59 of 64) of the patients with inflammatory bowel or hepatobiliary diseases and atypical p-ANCA. Affinity-purified antibodies against the 50-kilodalton protein gave a nuclear rim-like fluorescence on myeloid cells examined by immunofluorescence microscopy. Affinity-purified antibodies did not recognize antigens in nonmyeloid cells. CONCLUSIONS: Atypical p-ANCA in UC, PSC, or AIH recognize a 50-kilodalton myeloid-specific nuclear envelope protein.     

Contribution of immunofluorescence to identification and characterization of antineutrophil cytoplasmic antibodies in inflammatory bowel disease

We evaluated the combined use of different fixatives for the identification of atypical perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) in patients with inflammatory bowel diseases (IBD) by indirect immunofluorescence (IIF). Sera from 59 ulcerative colitis (UC) and 37 Crohn’s disease (CD) patients, and from 64 healthy controls were studied. The IIF on ethanol-, formalin-, and methanol-fixed neutrophils was used for the detection of ANCA. Enzyme linked immunosorbant assay (ELISA) was performed to identify the antigens recognized by ANCA. ANCAs were present in 35 of 59 (59.3%) UC patients and in 10 of 37 (27.02%) CD patients. Atypical p-ANCA positivity was strongly associated with UC disease (44.1% in UC vs. 8.1% in CD; p = 0.0002). The combined application of different fixatives contributed to make easy the differentiation between typical p-ANCA and atypical p-ANCA. Atypical p-ANCA determination appears to be a useful parameter for the distinction between UC and CD.     

Autoantibodies to neutrophil cytoplasmic (ANCA) and endothelial cell surface antigens (AECA) in chronic inflammatory bowel disease

Sera from 103 patients with chronic inflammatory bowel disease (IBD) were tested prospectively for antibodies against neutrophil cytoplasmic antigens (anti-neutrophil cytoplasm antibodies, ANCA) and endothelial cell surface antigens (anti-endothelial cell antibodies, AECA) by indirect immunofluorescence (IIF) and assays based on whole fixed neutrophils, purified neutrophil enzyme substrates and human umbilical vein endothelial cells. Using IIF, ANCA were found in 26 IBD sera (25%) and in none of 51 controls. Twenty-two positive sera (85%) were from patients with ulcerative colitis (UC). The pattern of distribution of immunofluorescence was always perinuclear (P-ANCA). A majority of UC patients positive for these autoantibodies (68%) had active colitis, but none had evidence of vasculitis. Using a whole neutrophil ELISA, binding was demonstrable in 73% of UC sera compared to 27% of Crohn's (CD) sera and only 4% of controls. Unlike vasculitis sera, UC sera with P-ANCA did not bind strongly to myeloperoxidase (MPO). Forty-five per cent of IBD sera tested positive for IgG AECA in an endothelial cell ELISA, compared to seven of 51 (14%) controls. Binding correlated with both active and extensive colitis. A type of P-ANCA, in most cases distinct from MPO-specific P-ANCA observed in vasculitis, is detected in a significant proportion of patients with UC, but rarely Crohn's colitis and therefore may be of differential diagnostic value. IgG AECA are also frequent in CIBD sera but are less disease specific than ANCA. (Aust NZ J Med 1992; 22: 652ndash;659.)     

Contribution of immunofluorescence to the identification and characterization of anti-neutrophil cytoplasmic autoantibodies. The role of different fixatives

OBJECTIVE: To study the sera from selected groups of antineutrophil cytoplasmic antibody (ANCA) positive patients by means of the indirect immunofluorescence test (ANCA-IIF) with different fixatives, in order to better discriminate among the various ANCAs (Ag-specificity and disease associations), especially those for which the antigen targets have not yet been identified. METHODS: Eighty pathological serum samples and 15 normal sera were evaluated. Pathological samples included sera from 30 ulcerative colitis (UC) ANCA positive patients, 30 P-ANCA/myeloperoxidase (MPO-ANCA) positive microscopic polyangiitis (MPA) patients, 10 C-ANCA/proteinase 3 (PR3-ANCA) positive Wegener's granulomatosis (WG) patients, and 10 antinuclear antibody (ANA) positive (ANCA negative) systemic lupus erythematosus (SLE) patients. ANCA were detected by IIF on ethanol, methanol and formalin-fixed granulocytes and by ELISAs specific for MPO, PR3, lactoferrin (LF) and bactericidal/permeability-increasing protein (BPI). Additionally, sera were tested for the presence of antinuclear antibodies on IIF. RESULTS: 96% of serum samples from UC patients, positive by IIF on ethanol-fixed granulocytes, became negative when tested on formalin-fixed neutrophil slides. On the contrary, 95% of sera from vasculitic patients showed a clear diffuse granular cytoplasmic pattern on the same substrate; sera from all 10 SLE patients did not show any reactivity when formalin was used as fixative. On methanol-fixed neutrophils, 100% of UC P-ANCA positive sera were positive with the same pattern versus only 20% of vasculitic P-ANCA positive (MPO positive). Methanol fixation had no effect on PR3-ANCA and ANA positive sera. CONCLUSION: The comparison of IIF patterns of sera tested on different fixed cells may be useful to distinguish vasculitis-related P-ANCA versus ANA and vasculitis-related P-ANCA versus UC-related P-ANCA.     

Atypical, cytoplasmic and perinuclear anti-neutrophil cytoplasmic antibodies in patients with inflammatory bowel disease

Atypical, cytoplasmic and perinuclear anti-neutrophil cytoplasmic antibodies (x-, c- and pANCA, respectively) are associated with a variety of inflammatory diseases, including inflammatory bowel disease (IBD). Anti-neutrophil cytoplasmic antibodies are more common in patients with ulcerative colitis (UC) than in patients with Crohn's disease (CD). Most publications only refer to p- and cANCA in relation to IBD. We have prospectively evaluated the reactivity of sera from 58 patients with IBD and 10 healthy controls against human neutrophils with emphasis on the distinction of the ANCA types. The sera were incubated with ethanol- and formaldehyde-fixed granulocytes to differentiate between c-, p- and xANCA. The results showed that 10 of 24 patients with UC were positive for ANCA, whereas only one of 34 patients with CD was ANCA positive. These results correspond to a sensitivity of 42%, a specificity of 97%, a negative predictive value of 91% and a positive predictive value of 75% in UC. Of the 11 ANCA-positive sera, two showed a cytoplasmic staining pattern, three showed a perinuclear and six an atypical staining pattern. The disease activity was not correlated to either the ANCA titre or to the presence of ANCA in the serum. In conclusion, ANCA are of limited value in differentiating between UC and CD. Because the majority of ANCA in patients with IBD are xANCA, these ANCA should be explored by not only incubating on ethanol-fixed granulocytes, but also on formaldehyde-fixed granulocytes.     

Antineutrophil cytoplasmic antibodies (ANCA) and small vessel vasculitis

We report on one patient with Wegener's granulomatosis (WG) and two patients with microscopic polyangiitis (MPA). The patient with WG had signs of a respiratory infection and showed a c-ANCA pattern with proteinase 3 (PR3) specificity. The patients with MPA presented with pulmonary haemorrhage and signs of renal damage and showed a p-ANCA pattern with myeloperoxidase (MPO) specificity. In the three patients histopathological findings confirmed the diagnosis. We discuss the clinical indications of ANCA testing and the current terminology for reporting ANCA results (c-ANCA, p-ANCA, c-ANCA (atypical) and atypical ANCA). The target antigens and diseases associated with these different patterns are considered. Finally we focus on the value of ANCA and more specific PR3-ANCA and MPO-ANCA in the diagnosis of WG and MPA. The new application domain of ANCA in Crohn's disease and ulcerative colitis is also discussed.     

Association of the HLA-DRB1＊0701 allele with perinuclear anti-neutrophil cytoplasmatic antibodies in Mexican patients with severe ulcerative colitis

AIM: To determine the association between the HLADRB1 alleles and perinuclear anti-neutrophil cytoplasmatic antibodies (p-ANCA) positive in Mexican patients with ulcerative colitis (DC). METHODS: Ninety Mexican mestizo patients (45 females) with DC, confirmed by biopsy, were studied. High resolution HLA typing was performed by PCR-SSO reverse dot blot and PCR-SSP. Molecular typing techniques were applied to define HLA-DRB1 alleles. Enzyme-linked immunosorbent assay and immunofluorescence techniques were used to detect p-ANCA. RESULTS: Forty-eight (53%) UC patients were positive for p-ANCA by ELISA and IF. We found that p-ANCA-positive UC patients had a significantly increased frequency of HLA-DR7 compared with p-ANCA-negative controls (22% vs 5.1%; pC = 0.02, OR = 5.2, CI 95%: 1.06-37.82). Disease activity was scored as severe in 20 patients, moderate in 8, mild in 14 and no activity in the remaining 38 patients according to the Truelove and Witts criteria. Subgroup analysis showed a significantly increased frequency of the HLA-DRB1*07 allele in 15 of 20 UC patients with severe activity of UC and p-ANCA positivity [100% vs 0%; pC = 0.0000001; OR = 35]. No significant differences were found between p-ANCA positive patients, HLA-DR alleles and other clinical features such as extraintestinal manifestations, proctocolectomy and extension. CONCLUSION: The HLA-DRB1*07 is associated with p-ANCA positive UC Mexican patients.     

Alpha1-antitrypsin phenotypes and anti-neutrophil cytoplasmic auto-antibodies in inflammatory bowel disease

OBJECTIVES: Alpha1-antitrypsin (alpha1-AT) is encoded by a highly polymorphic gene with over 75 codominantly expressed alleles at the protease inhibitor (Pi) locus classified as normal, deficient, dysfunctional or null. The aim of this study was to determine in patients with inflammatory bowel disease: (i) the prevalence of anti-neutrophil cytoplasmic auto-antibodies (ANCA) and their antigen specificities; (ii) alpha1-AT Pi phenotypes; and (iii) possible associations between ANCA, disease activity and deficient alpha1-AT alleles. DESIGN: Study of 95 consecutive patients with ulcerative colitis (UC) and 63 patients with Crohn's disease (CD). METHODS: Diagnosis and disease activity were determined by clinical, endoscopic and histological criteria. ANCA by indirect immunofluorescence (IIF) and Pi phenotyping by isoelectric focusing were performed for all patients. Positive IIF sera were tested in antigen-specific enzyme-linked immunosorbent assay: proteinase 3 (PR3), myeloperoxidase (MPO), lactoferrin (LF), lysozyme, human leucocyte elastase (HLE), cathepsin G and bactericidal/permeability increasing protein (BPI). RESULTS: Sixty-one patients with UC (64.2%) and only 11 with CD (17.5%) had ANCA (P < 0.001). Antigen specificities were PR3 (7/61), MPO (3/61), LF (6/61), HLE (1/63) and BPI (10/61) in UC, and PR3 (2/11) and BPI (2/11) in CD. Three PiZ alleles were found, matching the prevalence in the normal French control population. No relationship was found between the presence of ANCA, antibody specificity, disease activity and deficient alpha1-AT alleles. CONCLUSION: ANCA are more frequent in UC than CD and do not correlate with disease activity. ANCA and protease/antiprotease imbalance do not appear to modulate the clinical course of inflammatory bowel disease.     

Insecure Attachment in a Subgroup with Ulcerative Colitis Defined by ANCA Status

This study is the first test of the novel hypothesis that perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) marks an etiological division between stress-susceptible and stress-neutral ulcerative colitis. Subjects were 47 UC patients with known p-ANCA status (19 p-ANCA-positive, 28 p-ANCA-absent). Controls were 77 university students. Subjects and controls completed the Reciprocal Attachment Questionnaire. Subjects were categorized as avoidant/nonavoidant and anxious/nonanxious based on scores for compulsive self-reliance and compulsive care seeking, respectively. A higher prevalence of avoidant attachment was present in p-ANCA-absent (58.6%) than p-ANCA-positive subjects (22.2%, chi-square = 5.95, P < 0.02). There was no difference in the prevalence of anxious attachment between p-ANCA-absent and p-ANCA-positive subjects. There was no difference in clinical and psychiatric variables between groups. This finding provides support for a psychobiological contribution to UC in a subgroup identified by the absence of p-ANCA.     

Bactericidal/permeability-increasing protein and cathepsin G are the major antigenic targets of antineutrophil cytoplasmic autoantibodies in systemic sclerosis

OBJECTIVE: To study the prevalence and antigenic specificity of antineutrophil cytoplasmic autoantibodies (ANCA) in patients with systemic sclerosis (SSc). METHODS: Sera from 68 patients with SSc were screened for ANCA by indirect immunofluorescence (IIF) assay and for antibodies to myeloperoxidase (MPO) by ELISA. All sera positive for ANCA on IIF were analyzed for reactivity against antigenic targets other than MPO [bactericidal/permeability-increasing protein (BPI), cathepsin G, lysozyme, elastase, PR3, and lactoferrin]. Twenty-three sera negative for ANCA were also tested for antibodies to BPI and cathepsin G using ELISA. RESULTS: The study included 33 patients with diffuse and 35 with limited SSc. ANCA was detected in 24 of the 68 sera (35.3%). In these 24 sera the antigenic targets were BPI in 14, cathepsin G in 13, and MPO in 8. Sera of 11 patients had reactivity against both BPI and cathepsin G. In sera, that were negative for ANCA, antibodies to BPI (4/23), cathepsin G (3/23), and MPO (1/44) were found in a small proportion of patients. Patients with antibodies to BPI had lower skin score, whereas no patient with antibodies to MPO had renal disease. CONCLUSION: BPI and cathepsin G are the major antigenic targets of ANCA seen in patients with SSc. Patients with antibodies to BPI had lower skin scores.     

The prevalence and target antigens of antithyroid drugs induced antineutrophil cytoplasmic antibodies (ANCA) in Chinese patients with hyperthyroidism

OBJECTIVE: Antithyroid drugs such as propylthiouracil (PTU) and methimazole (MMI) are common medications in Chinese patients with hyperthyroidism and PTU-induced antineutrophil cytoplasmic antibody (ANCA) positive vasculitis has been reported. The current cross-sectional study aimed to investigate the prevalence and the target antigens of ANCA in Chinese patients with hyperthyroidism pre- and post-antithyroid medication therapy. METHODS: Sera from 216 patients with hyperthyroidism in our hospital were collected from January to July in 2002. Patients were divided into four groups: untreated (n = 34); treated with PTU (n = 62); treated with MMI (n = 77); and treated with both PTU and MMI (n = 43). Indirect immunofluorescence (IIF) assay was used to detect ANCA and ANA. Antigen-specific ELISAs were used to detect antigen specificities. The known antigens included myeloperoxidase (MPO), proteinase 3 (PR3), human leukocyte elastase (HLE), lactoferrin, bactericidal/permeability-increasing protein (BPI), cathepsin G and azurocidin. RESULTS: 33/216 sera were IIF positive, 20 of the 33 samples were ANCA positive, 11 samples were ANA positive, and two samples were both P-ANCA and ANA positive. The prevalence of positive ANCA in patients receiving PTU (14/62, 22.6%) was significantly higher than that of untreated patients (1/34, 2.9%) and patients treated with MMI (0/77, 0), P < 0.017. Of the 22 IIF-ANCA positive samples, 12 (54.5%) sera recognized lactoferrin, seven (31.8%) sera recognized HLE, four sera recognized MPO and azurocidin respectively, three sera recognized PR3 and cathepsin G respectively, and one serum recognized BPI. Six of the 22 (27.3%) patients with ANCA positive had clinical evidence of vasculitis. All patients with MPO-ANCA and two of the three patients with PR3-ANCA had clinical vasculitis. CONCLUSION: PTU is associated with the production of ANCA in patients with hyperthyroidism. PTU-induced ANCA are due to polyclonal activation of B cells. Anti-MPO and anti-PR3 antibodies may associate the occurrence of clinical vasculitis.     

Prevalence and specificity of antineutrophil cytoplasmic antibodies (ANCA) in connective tissue diseases

Antineutrophil cytoplasmic antibodies (ANCA) have specificity for constituents of neutrophil granules. There are two different types of ANCA identifiable by indirect immunofluorescence method. One type produces the cytoplasmic staining pattern (C-ANCA) and the second-perinuclear (P-ANCA). The aim of the study was to evaluate the frequency of ANCA in patients with connective tissue diseases (CTD). Serum samples were obtained from 394 patients suffering from CTD. The patients group consisted of 86 patients with lupus erythematosus systemic (LES) (including 30 with LES accompanied with glomerulonephritis), 136 cases with rheumatoid arthritis (RA) (including 18 patients with RA and vasculitis), 42 patients with systemic sclerosis (SSc), 76 cases of Sj?gren's syndrome (SS), 30 with Wegener's granulomatosis (WG), and 24 patients with polyarteritis nodosa (PAN). All patients fulfilled ARA criteria for the classification of CTD. The control group consisted of 42 healthy individuals. ANCA were detected by immunofluorescence method according to Wiik, and by an antigen-specific--enzyme-linked immunosorbent assay (ELISA). Proteinase 3 (PR-3), myeloperoxidase (MPO), elastase (ELA), lactoferrin (LC) and lysozyme (LZ), as well as cathepsin G were used as antigens in ELISA method. ANCA were detected in sera of 86 (21.8%) patients with CTD. C-ANCA pattern was observed in 28 (7.1%) cases, and p-ANCA in 58 (14.7%). C-ANCA were detected in sera of 28 (93%) patients with WG. P-ANCA were showed in 12 (13.9%) patients with LES, in 12 (50%) cases with PAN, in 20 (14.7%) with RA, in sera of 4 (9.5%) patients with SSc and in 10 (13.1%) with SS. No ANCAs were detected in healthy individuals. Ani-PR-3 antibodies were showed in sera of 26 patients, anti MPO in 30 cases, anti-ELA in sera of 12 patients, and anti-LC in 14 cases, but anti-LZ in 4 patients with CTD. The presence of ANCA in CTD patients may indicate the vascular inflammatory process during the course of the disease. It is a very important factor for the clinical course, and prognosis in the CTD patients.     

Antineutrophil cytoplasm antibodies (ANCA): description and immunopathological role

These antibodies are specific for antigens in the cytoplasm of neutrophils. The main antigenic targets are proteinase 3(PR3) and myeloperoxydase (MPO) but other targets have been described without determinant conclusions for clinical practice. Staining patterns can be distinguished by an indirect immunofluorescence test (IFI), in which ethanol fixed neutrophils from healthy donors are incubated with patient's sera. Two patterns are distinguished: cytoplasmic pattern (c-ANCA) and perinuclear pattern (p-ANCA). When ANCA are detected by IFI, from a practical point of view, anti -MPO and anti-PR3 antibodies are tested. ANCA have been strongly associated with a spectrum of necrotizing small vessel vasculitides that includes Wegener's granulomatosis, microscopic polyangiitis, Churg and Strauss syndrome, pauci-immune focal necrotizing and crescentic glomerulonephritis. ANCA are a diagnosic marker and useful for the follow-up of the patients. ANCA can be observed in other pathologies: rhumatismal autoimmune diseases, inflammatory gut diseases, after drugs (hydralazine, minocycline, propylthiouracil), after silical exposition, infections (cystic fibrosis, endocarditis, HIV infection). The specificity is different and rarely anti-MPO. The ANCA role for the development of vasculitis is not completely elucidated. Some arguments are against a primary role of ANCA in the development of vasculitis. Certainly, amplification role for neutrophil activation is demonstrated but the primary event responsible of neutrophil activation is not yet defined.     

抗中笥粒细胞胞浆抗体对溃疡性结肠炎的诊断价值

目的 探讨抗中性粒细胞胞浆抗体（ＡＮＣＡ）对溃疡性结肠炎（ＵＣ）的诊断价值。方法 应用间接免疫荧光法（ＩＩＦ）、酶联免疫吸附法（ＥＬＩＳＡ）和免疫印法（Ｗｅｓｔｅｍ ｂｌｏｔ）分别对ＵＣ患者（５８例）、非ＵＣ患者患者（４３例）及健康献血员（５８例）进行血清ＡＮＣＡ检测。结果 ＡＮＣＡ对ＵＣ诊断的敏感性为３７．９３％,特异性为１００％。ＵＣ患者中依据病情分为轻、中、重度组,ＡＮＣＡ的阳性率分别为１７     

Does analysis of the antigenic specificities of anti-neutrophil cytoplasmic antibodies contribute to their clinical significance in the inflammatory bowel diseases?

BACKGROUND: The clinical relevance of anti-neutrophil cytoplasmic antibodies (ANCA) in inflammatory bowel diseases is unclear. Definition of their antigenic specificities may improve their diagnostic significance. METHODS: We studied the target antigens of ANCA in 96 patients with ulcerative colitis (UC) and 112 patients with Crohn disease (CD) by indirect immunofluorescence, antigen-specific enzyme-linked immunosorbent assays, and immunodetection on Western blot. We related the presence of antibodies of defined specificity to clinical symptoms. RESULTS: By indirect immunofluorescence, ANCA were present in 58% of UC patients and in 21% of CD patients. Major antigens were catalase, alpha-enolase, and lactoferrin. In UC, ANCA titers correlated with disease activity. In CD, both ANCA, by indirect immunofluorescence, and antibodies to lactoferrin were associated with colonic localization of the disease. Neither ANCA, by indirect immunofluorescence, nor antibodies of defined specificity were associated with duration of disease, use of medication, or a history of bowel resection. CONCLUSIONS: ANCA are useful as markers for UC and colonic localization in CD. Definition of the antigenic specificities of ANCA in inflammatory bowel disease does not significantly contribute to their clinical significance.     

Hypercalcemia in a patient with B-cell acute lymphoblastic leukemia: a role of proinflammatory cytokine

BACKGROUND: Thyroperoxidase is the major antigen of the thyroid microsomal antibodies (TMA) detected in autoimmune thyroid diseases. Its amino acid sequence has 44% homology with myeloperoxidase (MPO), an enzyme present in the primary granules of neutrophils and one of the major antineutrophil cytoplasmic antibodies (ANCA) antigens. The objective of the present study was to investigate the presence of cross-reactivity to MPO of TMA. METHODS: We studied sera from 51 patients with autoimmune thyroid diseases, all of them TMA-positive. The presence of ANCA was investigated by indirect immunofluorescence and by capture enzyme-linked immunosorbent assay. RESULTS: ANCA were positive in 3.9% of the TMA-positive sera and none of them reacted with MPO. In contrast, the ANCA-positive sera revealed antielastase activity. None of the ANCA-positive cases presented clinical signs of vasculitis. However, these 2 patients had been on prolonged treatment with propylthiouracil. CONCLUSIONS: We conclude that there is no cross-reactivity to MPO of TMA in patients with autoimmune thyroid diseases, possibly because of difference in the spatial configuration of the immunodominant region. The presence of ANCA in patients with autoimmune thyroid diseases without evidence of vasculitis might result from propyIthiouracil-induced polyclonal activation.     

抗中性粒细胞胞浆抗体对溃疡性结肠炎的诊断价值

目的　探讨抗中性粒细胞胞浆抗体 (ANCA)对溃疡性结肠炎 (UC)的诊断价值。方法　应用间接免疫荧光法 (IIF)、酶联免疫吸附法 (ELISA)和免疫印迹法 (Westernblot)分别对UC患者 ( 5 8例 )、非UC患者 ( 4 3例 )及健康献血员 ( 5 8例 )进行血清ANCA检测。结果　ANCA对UC诊断的敏感性为 3 7.93 % ,特异性为 10 0 %。UC患者中依据病情分为轻、中、重度组 ,ANCA的阳性率分别为17 65 %、4 1.67%和 5 2 .94 %。ANCA阳性肠黏膜炎症III～V级者占 78 95 % ,黏膜血管炎发生率为78 95 % ,而ANCA阴性者分别为 3 7.0 4 %和 4 4.4 4%。髓过氧化物酶 (MPO)、杀菌 /通透性增强蛋白(BPI)、乳铁蛋白 (LF)、组织蛋白酶G(CG)、蛋白酶 3 (PR 3 ) 5种ANCA抗原与UC患者血清的结合率分别为 13 .79%、13 .79%、10 .3 4%、10 .3 4%和 8.62 %。采用Westernblot法对UC患者血清进行检测 ,发现显示特异蛋白条带者占 4 8.2 8% ,其中显示分子量为 4 70 0 0条带者最多 ,占 2 2 .4 1%。结论　ANCA检测可作为UC的辅助诊断手段。目前 ,UC相关ANCA的靶抗原仍未明确 ,研究发现 4 70 0 0蛋白可能是UC相关ANCA的靶抗原之一。ANCA可能参与UC的致病机制。     

Anti-neutrophil cytoplasmic antibodies (ANCA) in sera from patients with inflammatory bowel disease (IBD)

Anti-neutrophil cytoplasmic antibodies producing a perinuclear fluorescence pattern on ethanol-fixed granulocytes (p-ANCA) were found in 33 of 67 patients (49%) with ulcerative colitis (UC) but also in 14 of 35 patients (40%) with Crohn's disease (CD). In the latter condition p-ANCA were equally present in subgroups with colonic, ileocolonic, or ileal involvement only. Titers of p-ANCA were higher in patients with UC compared to CD patients, in particular when comparing patients with active disease. In contrast to findings in CD, patients with active UC had higher titers of p-ANCA than patients with inactive UC. Although p-ANCA were incidentally directed to lactoferrin, both in UC and CD, and to proteinase-3 and myeloperoxidase in UC only, the antigenic nature of p-ANCA could not be identified in most of the cases. We conclude that, within the spectrum of inflammatory bowel disease, the presence of p-ANCA is not specific for UC. When titers of p-ANCA are taken into account, the presence of high-titered p-ANCA, however, suggests active UC.     

Lack of association between HLA-DRB1 alleles of the major histocompatibility complex and p-ANCA status or clinical characteristics in patients with ulcerative colitis

INTRODUCTION: An association between different HLA-subtypes and ulcerative colitis has been described in various study populations of different ethnic and geographic background. Moreover, a correlation between HLA-DR2 and ulcerative colitis, in particular p-ANCA-positive ulcerative colitis, was reported. Thus, the present study aimed on the correlation of HLA-DRB1* alleles with the presence of p-ANCA and clinical characteristics in individuals of southern german descent. PATIENTS AND METHODS: The study population comprised 56 patients with ulcerative colitis and 177 healthy controls. HLA-DRB1* alleles were assessed by use of the dot blot method. Autoanti-bodies were visualized by indirect immunofluorescence on ethanol-fixed neutrophils. RESULTS: The allele HLA-DRB1*12 was more frequent in patients with ulcerative colitis (p = 0.01). After correction for the number of alleles tested (n = 16) statistical significance was no longer preserved. A weak association between the presence of HLA-DR5 and the detection of p-ANCA in ulcerative colitis was found (p = 0.0375). After correction for the number of comparisons (n = 10) no associations between HLA-DR antigens and the presence of p-ANCA remained. Furthermore, no significant correlations between clinical characteristics of ulcerative colitis and HLA-DR antigens were detected. DISCUSSION: Genes encoding for HLA-DR antigens are unlikely to have an impact on the heredity and the presence of disease phenotypes of ulcerative colitis in a study population of southern german descent.     

Antineutrophil Cytoplasmic Antibody in Patients with Primary Sjo¨gren’s Syndrome

The incidence, specificity and clinical significance of positivity for serum antineutrophil cytoplasmic antibody (ANCA) was investigated in 60 patients with primary Sj?gren's syndrome (SjS). The indirect immunofluorescence (IIF) technique and an enzyme-linked immunosorbent assay (ELISA) were used to measure ANCA. Purified myeloperoxidase (MPO), lactoferrin (LF), cathepsin-G (CTG) and elastase (HLE) served as ANCA antigens for the ELISA. Ten (16.7%) of the 60 SjS patients showed positivity by IIF for perinuclear, but not cytoplasmic, ANCA. Four of the 60 sera were shown to be positive for LF, four for MPO, 0 for CTG and 0 for HLE by ELISA. There was no correlation between ANCA positivity and clinical features. ANCA in patients with SjS might be an epiphenomenon of polyclonal B-cell activation.