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Benign or idiopathic intracranial hypertension, also termed 'pseudotumour cerebri', is defined by the presence of raised intracranial pressure (ICP) in the absence of a focal intracerebral space-occupying lesion. The signs and symptoms of elevated intracranial pressure are also observed such as headaches, nausea and vomiting, elevated arterial pressure and, often, bradycardia. Somnolence and palsy of the abducens nel ve are occasionally observed, while papilloedema causing reduction of visual acuity and blindness is a particularly defining feature.

Increased titres of anti-dsDNA antibodies, especially if of high avidity, are associated with renal exacerbations in patients with systemic lupus erythematosus (SLE). One of the most reliable assays to measure anti-dsDNA antibodies, the Farr assay, is believed to detect preferentially high avidity antibodies. Purified non-complexed monoclonal antibodies (mAbs) against nucleosomes, obtained from mice with SLE, are not reactive in the Farr assay, but can become so once complexed to nucleosomes, These Farr-positive, nucleosome containing, immune complexes were also able to bind in vivo to the glomerular basement membrane (GBM), predominantly via heparan sulphate (HS). To evaluate whether in SLE patients the same kind of immune complexes are responsible for Parr reactivity, IgG from serum or plasma was isolated under dissociating and physiological conditions. We observed that after purification under dissociating conditions, Farr reactivity was significantly decreased (P

Since the first detection of ANCA in IBD, numerous studies have dealt with their prevalence, antigenic specificities, clinical significance, pathophysiological role, and their induction. This review summarizes the information obtained from those studies and shows that ANCA are not directly useful as diagnostic and prognostic factors in IBD. ANCA were detected in 50-85% of patients with ulcerative colitis (UC) and 10-20% of patients with Crohn's disease (CD). Multiple target antigens are recognized by these autoantibodies, including both cytoplasmic and nuclear proteins. A pathophysiological role for ANCA in IBD is far from clear. On the one hand, it is suggested that ANCA are genetic markers of susceptibility for IBD, and on the other hand, the induction of ANCA in those diseases may just be an epiphenomenon of chronic inflammation. We discuss recent evidence that ANCA may be induced by a break-through of tolerance towards bacterial antigens.

Background: Autoimmune mechanisms are postulated to play a role in the development and progression of Wegener's granulomatosis (WG), a form of systemic, idiopathic necrotizing vasculitis,Objective: We investigated the relation between lymphocyte activation and disease activity in patients with WG, Methods: B- and T-lymphocyte activation was studied by cytometric assessment of the expression of the activation markers CD38 on B cells and CD25 and HLA-DR on CD4(+) and CD8(+) T-cell subsets, respectively. Activation at the cellular level was related to serum levels of antineutrophil cytoplasmic antibodies and soluble IL-2 receptor, which can be regarded as soluble activation markers of B and T cells.Results: Percentages of CD38(bright) activated B cells were higher in patients with active WG than in patients experiencing disease remission (P Conclusion: In WG, B-cell activation is related to active disease, whereas T-cell activation persists during remission of the disease, which points to an intrinsic disordered immune system in this disease.

Vascular injury in vasculitis may be due to activation of circulating neutrophils resulting in their increased adhesiveness to locally activated endothelium (Shwartzman phenomenon). Previously, we demonstrated up-regulation of endothelial intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in biopsies from patients with ANCA-associated vasculitis. In the present study, we investigated the expression of adhesion molecules (CD11b, ICAM-1, VLA-4, L-selectin) and activation markers (CD66b, CD64, CD63) on circulating neutrophils from patients with ANCA-associated vasculitis in comparison with their expression on cells from healthy volunteers and patients with sepsis. We related these findings to parameters of disease activity. Surface marker expression was determined by using a non-activating whole blood flow cytometric assay. The expression of activation markers: but not the expression of adhesion molecules, was increased on neutrophils from patients with active vasculitis. The expression of CD63 and CD66b on neutrophils correlated with disease activity as determined by the Birmingham Vasculitis Activity Score (BVAS). In contrast to patients with active vasculitis, patients with sepsis showed up-regulation of all markers, including adhesion molecules, suggesting that circulating neutrophils are fully activated in sepsis. We conclude that in ANCA-associated vasculitis, circulating neutrophils are not fully activated, since they do not express increased levels of adhesion molecules as sepsis or in the Shwartzman reaction. These findings are compatible with the concept that in vivo vascular damage in ANCA-associated vasculitides does not occur due to a Shwarzman-like reaction but only after ANCA-induced neutrophil activation at the endothelial cell surface.

PURPOSE: The clinical significance of antineutrophil cytoplasmic autoantibodies (ANCA) in primary sclerosing cholangitis has not been established. We investigated whether analysis of the antigenic specificities of ANCA is useful for delineating clinical subsets of the disease. METHODS: Sixty-nine patients with primary sclerosing cholangitis were studied. The presence of ANCA was analyzed by indirect immunofluorescence. Antibodies directed against specific antigens-proteinase 3, myeloperoxidase, elastase, bactericidal/permeability-increasing protein, cathepsin G, and lactoferrin-were identified by enzyme-linked immunosorbent assay. RESULTS: ANCA were detected by indirect immunofluorescence in 46 (67%) patients. In antigen-specific enzyme-linked immunosorbent assays, 37 (55%) of the 69 patients had antibodies to one or more antigens: 32 (46%) had antibodies to bactericidal/permeability-increasing protein, 16 (23%) had antibodies to cathepsin G, and 15 (22%) had antibodies to lactoferrin. Only 3 patients had antibodies to proteinase 3. Antibodies to myeloperoxidase or elastase were not detected. Twenty (29%) patients had antibodies to different antigens simultaneously. ANCA as detected by indirect immunofluorescence were not significantly associated with the presence of cirrhosis nor with the coexistence of inflammatory bowel disease. However, antibodies to bactericidal/permeability-increasing protein and cathepsin G were both associated with the presence of cirrhosis, and antibodies to lactoferrin were more frequently detected in patients with primary sclerosing cholangitis in conjunction with ulcerative colitis than in those without inflammatory bowel disease. CONCLUSION: Defined specificities of ANCA in primary sclerosing cholangitis may be related to particular clinical features of the disease. (C) 1998 by Excerpta Medica, Inc.

SUMMARY In a previous study it was shown that La/SSB contains four linear epitopes, p147–154, p291–302, p301–318 and p349–364. The aim of the present study was to investigate the value of the synthetic epitope analogues of the La/SSB autoantigen for the detection of antibodies to La/SSB, in comparison with recombinant La and fragments of this protein. A total of 122 sera with anti-La/SSB activity, from patients with primary Sjögren's syndrome (pSS) or systemic lupus erythematosus (SLE), were tested in various peptide-based assays. In addition, 62 sera from pSS or SLE patients with other autoantibody specificities and 95 sera from healthy individuals were used as controls. The autoantibody specificity was identified by counter immunoelectrophoresis and immunoblot. The peptide-based ELISA assays presented sensitivities ranging from 78% to 88.8% and specificities from 69% to 94.3%. Dot blot assays exhibited sensitivities ranging from 93.6% to 97%, but remarkably lower specificities from 56% to 88%. The most sensitive and specific peptide 349GSGKGKVQFQGKKTKF364 was synthesized and attached on a tetramer sequential oligopeptide carrier SOC4 and used for immunoassay development. Assays based on the recombinant native La protein, the La-C terminal (215 aa), and the N-terminal of La with a mutation at base pair 640 (nine adenines instead of eight) were also developed and compared with the SOC4 peptide-based assay. Of anti-La-positive sera, 88.1% were reactive with both the synthetic peptide SOC4-(349–364aa) and the recombinant La protein. Eighty-three percent of sera were reactive with the La N-terminus and 67.8% of sera were reactive with the La C-terminus. Using sera that were anti-Ro-positive but anti-La-negative, 37% were reactive with the recombinant protein, 26% with the La N-terminus, 33% with the La C-terminus and only 11% with the synthetic peptide. Our results suggest that the synthetic peptide epitopes exhibit high sensitivity and specificity for the detection of anti-La/SSB antibodies in ELISA and dot blot techniques. The peptide SOC4-(349–364aa) has the same sensitivity for the detection of anti-La/SSB antibodies as the recombinant protein.

The PPGMRPP sequence, found in several copies in the Sm and U1RNP autoantigens, is the main target of anti-Sm and anti-U1RNP antibodies in systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD) patient's sera. It is also recognized, to a lower extent, by anti Ro/SSA and anti-La/SSB specificities. The PPGMRPP-NH2 peptide amide and the PPGMRPP peptide, which is bound to a pentameric sequential oligopeptide carrier (SOC5), were examined by H-1-NMR spectroscopy and ELISA assays, using sera from patients with autoimmune rheumatic diseases. Among the three main conformers found for the free PPGMRPP, the extended one was also identified for PPGMRPP-NH2 and (PPGMRPP)(5)-SOC5. This can be attributed to the absence of ionic interactions between the Arg-guanidinium and the carboxylate group in the amide and SOC5-bound forms of the peptide. Immunoassays using sera from various specificities showed an enhanced anti-Sm and anti-U1RNP recognition of PPGMRPP-NH2 and (PPGMRPP)(5)-SOC5, and lowering of the anti-Ro/SSA and anti-La/SSB reactivity. The presence of multiple conformers of free PPGMRPP may explain the unexpected cross-reactivity to the anti-Ro/La positive sera, while the prevalence of the extended conformation in PPGMRPP-NH2 and (PPGMRPP)(5)-SOC5 is mainly responsible for the enhanced recognition from the anti-Sm and anti-U1RNP autoantibodies. It is concluded that the antigenic specificity of PPGMRPP-NH2 and (PPGMRPP)(5)-SOC5 is mainly induced by conformational changes resulting from the conversion of the C-terminal carboxylate group to the amide form. Letters in Peptide Science

Objective: To characterize the putative target antigens for antiendothelial cell antibodies (AECA), the possible pathophysiological role of AECA, and the clinical value of these antibodies as markers of disease activity, Methods: A structured literature search was done using Medline in combination with a manual search. Two physicians reviewed all articles of special interest. Results: AECA are a heterogenous group of antibodies directed against a variety of antigen determinants on endothelial cells (EC). The EC antigens can be constitutively expressed, constitutively expressed and modulated by cytokines, or cryptic. In addition, antigen determinants for AECA may also be molecules that adhere to EC (''planted'' antigens). However, many AECA antigens are currently not well characterized, AECA are detected in a wide variety of inflammatory disorders. Although probably of limited value in disease diagnosis, the detection of these antibodies may be valuable in following disease activity. In several diseases such as systemic lupus erythematosus and systemic vasculitis, high AECA titers are found during active disease whereas lower titers or disappearence of AECA have beers reported during remission. The correlation between changes in AECA titers and disease activity suggests an important role for AECA in processes in which vessel wall damage occurs, although it does not exclude the possibility that AECA are an epiphenomenon of vascular injury Several recent in vitro studies support a role of AECA in the pathophysiology of these inflammatory disorders. AECA may play a role in the pathophysiology by inducing activation af: EC resulting in upregulation in the expression of endothelial adhesion molecules and/or secretion of chemoat-tractants and cytokines, An alternative mechanism by which AECA could be a trigger in the pathogenesis of some diseases is complement dependent cytotoxicity (CDC) and/or antibody dependent cellular cytotoxicity (ADCC). In experimental animal models, antibodies to antigenic determinants expressed on EC were capable of inducing vascular injury. Conclusion: AECA represent a heterogenous group of antibodies directed against a variety of antigenic determinants on EC. They are present in a variety of inflammatory disorders, The detection of these antibodies may be valuable in following disease activity further characterization of putative antigens is needed to better understand their pathophysiological role.

The primary vasculitides are diseases of unknown aetiology. They are characterized by inflammation of blood vessel walls, Measuring non-specific laboratory markers of inflammation is useful in the monitoring of patients with vasculitis. The diagnostic specificity of these markers is, however, restricted. In the last decade, autoantibodies reacting with myeloid granule proteins have been detected in the sera from patients with Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome, and the renal limited form of these vasculitides (i.e. idiopathic rapidly progressive glomerulonephritis). Anti-neutrophil cytoplasmic antibodies (ANCA) in the aforementioned disorders react with proteinase 3 (Pr3) or myeloperoxidase (MPO), and only incidentally to other antigens such as elastase and bactericidal-permeability increasing protein, The presence of ANCA alone, in particular perinuclear ANCA, as detected by indirect immunofluorescence, has a low specificity for those vasculitides, However, in combination with the presence of anti-Pr3 or anti-MPO antibodies as detected by enzyme-linked immunosorbent assay, sensitivity and specificity for the vasculitides is high. Several in vitro and in vivo data have suggested a pathophysiological role for anti-Pr3 and anti-MPO in the associated disorders. Measuring levels of the autoantibodies seems useful for the follow-up of patients with these vasculitides. The sensitivity and specificity of rises in ANCA levels for ensuing relapses appears somewhat lower than previously suggested. Refinement of the assays, for example, by measuring subclasses and functional characteristics of the autoantibodies, may improve their value in monitoring patients with vasculitides.

It has been suggested that binding of anti-double-stranded DNA antibodies to cell surfaces, followed by internalization and nuclear binding (so called in vivo ANA) is of pathophysiological significance for tissue damage in systemic lupus erythematosus. We have shown before that pathogenic antinuclear antibodies complexed to nucleosomal antigens can bind to heparan sulfate in the glomerular basement membrane in vivo. Because nucleosomes are also reported to bind to the cell surface, we hypothesized that in vivo ANA is a property of antinuclear antibodies bound to nucleosomal antigens. Therefore, we studied three antinucleosome monoclonal antibodies (mAb) that exhibit in vivo ANA as seen by immunofluorescence in mice inoculated intraperitoneally with the hybridoma producing the mAb. The same mAb complexed to nucleosomal antigens after intravenous injection into mice induced in vivo ANA, in contrast to purified noncomplexed mAb. To study this In more detail, we incubated complexed mAb with various cell lines and found binding to the cell surface and subsequent internalization into cytoplasmic vesicles. However, no binding to the nucleus was observed by immunoelectron microscopy (IEM) and confocal laser microscopy. Noncomplexed mAb did not bind to the cell surface, Next, from mice bearing the hybridomas producing the mAb intraperitoneally, a small part of the kidney was snap frozen in liquid N-2, fixed with acetone, and studied In immunofluorescence, whereas the remaining part of the kidney was fixed In vivo by renal perfusion with a mixture of 0.01 M sodium periodate, 0.075 M lysine HCI, 0.0375 M Na2HPO4, and 2% paraformaldehyde (PLP) and studied in both immunofluorescence and IEM. In the acetone-fixed kidney sections obtained without in vivo fixation we again observed in vivo ANA. However, after in vivo PLP perfusion fixation, no nuclear binding was found. in IEM, localization in cytoplasmic vesicles was seen. in conclusion, antinucleosome antibodies complexed to nucleosomal antigens can bind to the cell surface and are transported into the cytoplasm, but do not bind to the nucleus. The reported nuclear localization of antinuclear antibodies is caused by a fixation artifact.

A 59-year-old man was diagnosed as having constrictive pericarditis 17 months after a typical hydralazine-induced autoimmune syndrome, This late complication of hydralazine has been reported only once. Ten years later the patient was found to have anti-neutrophil cytoplasmic antibodies directed against myeloperoxidase.

Reactivity of serum antibodies with heparan sulfate (HS) has been associated with human and murine lupus nephritis, although the aetiological significance of this association is not clear. Recent work from our laboratories showed that binding of these antibodies to HS could be mediated by histone containing immune complexes. In human lupus nephritis we found a strong decrease in HS staining in the glomerular basement membrane (GBM). The aim of this study was to elucidate the correlation in experimental systemic lupus erythematosus (SLE) between albuminuria, staining of HS in the GEM and anti-DNA and anti-HS reactivity in plasma. We therefore studied NZB/W F1 mice during different stages of glomerular disease and compared them with age matched control NZB/W F1 mice without albuminuria. Anti-DNA and anti-HS reactivity were measured in longitudinally collected plasma samples and correlated with the onset of albuminuria, staining of HS in the glomerular basement HS staining was of mice with prolonged proteinuria in comparison with age matched control mice (P=0.0013). This decreased HS staining was correlated with increased Ig deposition in the capillary loops (tau=-0.42, P

The records of 46 patients with anti-(U1)snRNP antibodies and a minimal period of follow-up after first clinical presentation of at least 5 yr were examined with emphasis on symptoms contributing to established criteria of SLE, systemic sclerosis (SSc), RA or dermato- or polymyositis (DM/PM). At first clinical presentation 13 (28%) of the 46 patients studied fulfilled ARA-criteria for SLE (n = 10), RA (n = 2) and SSc (n = 1), and 33 (72%) were classified as mixed connective tissue disease (MCTD). During follow-up 18 patients initially classified as MCTD were now classified as SLE (n = 5), SSc (n = 7), RA (n = 3), or a combination of these disorders (n = 3). A transformation of MCTD towards these connective tissue diseases occurred 2.6 +/- 3 yr (mean +/- S.D.) after first clinical presentation. At the end of the follow-up period 67% of the patients fulfilled ARA criteria for SLE, SSc, RA or a combination of these diseases.The majority of patients with anti-(U1)snRNP antibodies have or will develop a classified connective tissue disease within 5 yr after clinical presentation. This undermines the concept of MCTD being a distinct clinical entity.

Autoantibodies reacting with a great variety of autoantigens are characteristic for the autoimmune disease systemic lupus erythematosus (SLE). Although reactivity with heparan sulfate (HS) in sera of patients with SLE is found in association with the occurrence of nephritis, the aetiological significance of this association is not clear. The assay which is generally used to measure anti-HS reactivity is subject to false-positive results, as a consequence of the binding of negatively charged moieties within immune complexes to the precoat employed (protamine sulfate). Therefore, we have developed a new ELISA in which photobiotinylated HS is efficiently and reproducibly bound to streptavidin-coated wells. We compared the new ELISA with the classical anti-HS ELISA by testing culture supernatants of 20 murine monoclonal antibodies (mAb) to DNA (containing free anti-DNA and anti-DNA/nucleosome immune complexes) and preparations of these mAb (containing only free anti-DNA), purified under dissociating conditions. In the classical anti-HS ELISA, 14 out of 20 of the culture supernatants reacted positively with HS; after purification no reactivity remained. The discrepancy must be due to anti-DNA/nucleosome immune complexes present in the culture supernatants. In the new ELISA only four out of 20 culture supernatants and one of the purified preparations reacted with HS. This latter reactivity is probably not specific, since this mAb also reacted with streptavidin alone. To find out whether there is a correlation between the occurrence of nephritis and anti-HS reactivity, measured in this new anti-HS ELISA, we tested sera of patients with a renal- or non-renal exacerbation of SLE in the newly developed anti-HS ELISA. We observed a correlation between anti-HS reactivity and nephritis.

Histones can mediate the binding of DNA and anti-DNA to the glomerular basement membrane (GBM). Zn ELISA histone/DNA/anti-DNA complexes are able to bind to heparan sulfate (HS), an intrinsic constituent of the GBM. We questioned whether histone containing immune complexes are able to bind to the GBM, and if so, whether the ligand in the GBM is HS. Monoclonal antibodies (mAbs) complexed to-nucleosomal antigens and noncomplexed mAbs were isolated from culture supernatants of four IgG anti-nuclear mAbs. All noncomplexed mAbs showed strong anti-nucleosome reactivity in ELISA. One of them showed in addition anti-DNA reactivity in noncomplexed form. The other three mAbs only showed anti-DNA reactivity when they were complexed to nucleosomal antigens. After renal perfusion a fine granular binding of complexed mAbs to the glomerular capillary mall and activation of complement was observed in immunofluorescence, whereas noncomplexed mAbs did not bind. Immuno-electron microscopy showed binding of complexes to the whole width of the GBM. When HS in the GBM was removed by renal heparinase perfusion the binding of complexed mAb decreased, but did not disappear completely. We conclude that anti-nucleosome mAbs, which do not bind DNA, become DNA reactive once complexed to nucleosomal antigens. These complexed mAbs can bind to the GBM. The binding ligand in the GBM is partly, but not solely, HS. Binding to the GBM of immune complexes containing nucleosomal material might be an important event in the pathogenesis of lupus nephritis.

Objective. To assess the value of measuring serum levels of soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), and soluble E-selectin for monitoring disease activity in Wegener's granulomatosis (WG).Methods. A sandwich enzyme-linked immunosorbent assay was used to measure levels of soluble adhesion molecules at the time of diagnosis in 22 consecutive patients with WG, in 12 WG patients studied serially prior to disease relapse, at the time of upper airways infection in 18 patients with inactive WG, and in 57 controls. Disease activity was assessed by disease activity score and C-reactive protein levels.Results. At diagnosis of WG, sICAM-1 and sVCAM-1 levels were significantly elevated and correlated with disease activity. At the time of relapse, a significant increase in all 3 soluble adhesion molecules was found compared with levels at 6 months prior to relapse, but only sVCAM-1 levels were significantly elevated compared with those in controls. Levels of soluble adhesion molecules at the time of relapse did not differ from those measured during an upper airways infection without disease activity.Conclusion. Elevated serum levels of sICAM-1 and sVCAM-1 can be found in active WG and correlate with disease activity. However, their clinical relevance for followup is limited due to lack of sensitivity and specificity for WG disease activity.

The measurement of anti-dsDNA antibodies is important for the diagnosis and the follow-up of patients with systemic lupus erythematosus (SLE). For routine detection of anti-dsDNA, the Farr assay and the immunofluorescence technique (IFT) on Crithidia luciliae proved to be very useful. The anti-dsDNA ELISA is not used for routine purposes in our institute since it is flawed by false-positive results due to binding of negatively charged (immune) complexes to the employed precoat (protamine sulphate). Recently, a new anti-dsDNA ELISA has been described in which photobiotinylated dsDNA is coated to streptavidin coated plates. To investigate whether this modified ELISA is more specific than the classical anti-dsDNA ELISA, we tested sera of patients with SLE (n = 51), myasthenia gravis (MG, n = 25), rheumatoid arthritis (RA, n = 25) and Sjogren's syndrome (SS, n = 23) and sera of healthy blood bank donors (BBD, n = 25). In both assays the sera of the SLE patients gave significantly higher values than the sera of healthy blood bank donors. In the classical ELISA, 84% of the sera from patients with RA and 28% of sera of patients with MG were found positive. For the modified assay the figures were 8% and 24%, respectively. This modified ELISA was further studied and clinically evaluated by comparing it with the classical anti-DNA ELISA and two other anti-DNA assays (Farr assay and IFT), using 500 sera sent to our institute for routine anti-DNA determination and sera of an additional 75 healthy blood bank donors. Quantitatively, both ELISAs showed the same high degree of correlation with the IFT. The modified ELISA gave a better correlation with the Fan assay than the classical anti-DNA ELISA. From our data we conclude that the ELISA using photobiotinylated DNA is a more reliable assay than the classical anti-DNA ELISA.

To obtain insight in the effect of TNF on the synthesis of acute phase proteins like CRP, alpha 1-antitrypsine, alpha 1-acidglycoprotein, C3 and C4 and the immunoglobulins (IgG-M-A), nine cancer patients who were treated with an isolated limb perfusion (ILP) with high dose recombinant TNF-alpha (rTNF-alpha) were investigated during a 7-day period after the end of the perfusion. Resorption of rTNF-alpha from out of these limbs into the circulation after the ILP induced within 30 min to 6 h in all patients elevated serum levels of IL6. At the same time C-reactive protein became detectable in serum. The highest serum levels were obtained at 48 h after ILP. The serum levels of the other acute phase proteins (alpha 1-acidglycoprotein, alpha 1-antitrypsine, C3, C4), rose more slowly and the highest serum levels were found at the third day. All investigated proteins declined after they had reached their peak levels. Levels of alpha(1)-acidglycoprotein and alpha(1)-anti-trypsin alpha(1)-acid declined slower than both complement component. In regard to the immunoglobulin levels a nearly continuous increase in the serum level of specifically IgM was observed. This study clearly shows the interrelationship between TNF-alpha and IL-6 in regard to the synthesis of the different acute phase proteins; and moreover also a striking effect on IgM synthesis.

Levels of soluble IL-2 receptor (sIL-2R), soluble CD4 (sCD4) and CD8 (sCD8) were measured by sandwich ELISA as markers for T cell activation in serial serum samples from 16 patients showing 18 histologically proven relapses of Wegener's granulomatosis (WG). Levels of sIL-2R increased from 1065 U/ml (median, range 373-2345 U/ml) 6 months before the relapse to 1684 U/ml (median, range 486-3404 U/ml) at the moment of relapse for the whole group (P= 0.10). The eight major relapses showed a profound rise in sIL-2R levels, from 1008 U/ml (median, range 686-1553 U/ml) 6 months before the relapse, to 1994 U/ml (median, range 1469-3404 U/ml) at the moment of relapse (P

In view of evidence suggesting vitiligo is an autoimmune disease, we investigated whether vitiligo is associated with inherited deficiencies of the fourth (C4) and second (C2) component of complement and with certain human leukocyte antigens (HLA). Analysis of functional activities of C4 and C2 in sera of patients with vitiligo (n = 42) showed that 17% of them had a heterozygous C4 deficiency and 5% had a heterozygous C2 deficiency. In the normal control group (n = 30), 3% had a heterozygous C4 deficiency and none had a C2 deficiency. C4 typing by Western blot analysis showed the frequency of the C4A*QO allele in the vitiligo patient group to be close to normal. However, the frequency of one C4B*Q0 allele was three times higher, and that of two C4B*Q0 alleles five times higher in the vitiligo patient group than the reported frequencies in normal control groups. Southern blot analysis of Taq1 digests of DNA using C4 and 21-hydroxylase probes showed that two patients with two C4B*Q0 alleles had a deletion of a 21-OHA-C4B segment. In the other patients, having one or two C4B*Q0 alleles, these null alleles probably occurred due to a loss of C4 gene expression. HLA analysis did not show any allelic association of C4A*Q0 or C4B*Q0 with any HLA antigen in vitiligo, but confirmed the previous findings of a negative association with HLA-DR3 and a positive association with HLA-DR4. These results suggest that abnormalities of the C4B gene and the above-mentioned associations with HLA antigens may be some of the risk factors in vitiligo.

Antibodies against ribosomal phosphoproteins (anti-P antibodies) are found in about 10% of patients with systemic lupus erythematosus (SLE). Using an ELISA with a synthetic peptide for screening and an immunoblotting technique as a confirmation test for detection of these antibodies, we found 16 positive patients among 946 sera sent to our reference laboratory for anti-DNA determination. All 12 patients on which we could obtain clinical data had clearcut SLE, fulfilling 6 ARA criteria on average. Skin symptoms were observed more frequently in anti-P positive than in anti-P negative patients with SLE. We also tested 56 sera from 54 patients with well defined SLE during monosymptomatic exacerbations and found and identical frequency of about 10% of anti-P antibodies in groups of patients with different types of exacerbation, including psychosis. A retrospective analysis of 9 patients followed 3-10 years showed that they all were already positive for anti-P at the onset of disease. In total these patients showed 15 major peaks in anti-P levels (defined as at least a 4-fold rise in titer in a period of 3 months). Five of the fluctuations in anti-P levels were paralleled by fluctuations in anti-DNA levels. In 6/15 cases, peaks of anti-P levels were accompanied by an exacerbation of SLE, but only 2 peaks of anti-P levels were already detectable before the onset of the exacerbation. In addition, 6 other exacerbations occurred in the absence of major anti-P rises in the preceding 3 months. Therefore, quantitative determinations of anti-P have at most a limited practical value in the followup of patients with SLE.

In view of the supposed hypersensitivity, the elevated levels of IgE, and the occurrence of eosinophilia reported in Wegener's granulomatosis and related conditions, we studied the IgG subclass distribution of ANCA directed against a 29-kD serine protease and and myeloperoxidase (MPO) in 41 untreated ANCA-positive patients with several forms of active vasculitis and/or glomerulonephritis. We found that both 29-kD ANCA and MPO ANCA were predominantly of the IgG1 and IgG4 subclass in all groups of patients. The additional presence of IgG3 subclass was associated with renal involvement. We compared the subclass distribution of ANCA with that of total IgG subclass levels, and with the IgG subclass distribution of antibodies to cytomegalovirus (CMV) as a persistent endogenous antigen and antibodies to tetanus toxoid (TT) as an exogenous recall antigen. Total levels of IgG4 were elevated in the majority of the patients together with elevated IgG1 levels. Antibodies to CMV and TT, however, had the same subclass distribution as found in normals and did not show enhanced IgG4 expression. ANCA belong predominantly to the IgG1 and IgG4 subclass, which may suggest that the production of ANCA is related to recurrent exposition to the antigen(s) involved, possibly as part of a hypersensitivity reaction.

La/SSB phosphoprotein is the target antigen of autoantibodies in sera of patients with Sjogren'syndrome (SS) and systemic lupus erythematosus (SLE). Among other structural and junction motifs, four phosphorylation sites are encompassed in the primary sequence of La/SSB. Two of them (Thr-362 and Ser-366) are located within GSGKGKVQFQGKKTKFASDD (346-368) and one (Thr-302) within VTWEVLEGEVEKEALKKI (301-318), which are main B-cell epitopes of La/SSB. With the aim to investigate how phosphorylation, one of the most common posttranslational protein modifications, affects the antigenic and conformational characteristics of the La/SSB epitopes, we synthesized and studied the phosphorylated epitopes La/SSB(346-368)-P, La/SSB(359-368)-P, and La/SSB(301-318)-P with respect to their nonphosphorylated counterparts. Anti-La/SSB positive sera from SS and SLE patients are better recognized by the phosphorylated epitopes compared to their nonphosphorylated counterparts. Conformational analysis by 111 nuclear magnetic resonance spectroscopy and molecular dynamics showed that the phosphorylated epitopes adopt different structural characteristics from those of the corresponding nonphosphorylated epitopes. It is concluded that phosphorylation can create neoepitopes with altered functions, compared to the nonphosphorylated epitopes, which might be seen from the immune system as "foreign." (c) 2006 Wiley Periodicals, Inc. Biopolymers

The purpose of this study was to investigate the biochemical characteristics as well as the occurrence and specificity of antiphospholipid antibodies in the bronchoalveolar lavage (BAL) fluid from a patient with both antiphospholipid antibodies syndrome (APS) and acute respiratory distress syndrome (ARDS). Proteins, lipids, cells and autoantibodies were determined. Immunoglobulins were purified with affinity chromatography. Autoantibody identification was assessed with enzyme-linked immunosorbent assay (ELISA) and with electrophoresis, followed by immunoblotting and revelation with antihuman IgG-peroxidase conjugate. Antiphospholipid antibodies were found to be present in the BAL fluid as well as in the serum from a patient with APS. Specifically, antiphosphatidylserine and antiphosphatidic acid IgG antibodies in the BAL fluid and antiphosphatidylcholine and anticardiolipin IgG antibodies in the serum were detected at high levels. BAL fluid protein and the percentage of neutrophils were found to be increased. R quantitative as well as qualitative deficiency of surfactant phospholipids was also observed. Antibodies directed against surfactant phospholipids could cause surfactant abnormalities and an inflammatory reaction. These disorders may be one of the causes of the ARDS or a factor in the perpetuation of the inflammation. Clin Rheumatol

Objective: To investigate the presence of autoantibodies to lipids in the bronchoalveolar lavage (BAL) fluid from adult patients with acute respiratory distress syndrome (ARDS). Design: Analysis of immunoglobulin G (IgG) in BAL fluid by electrophoresis followed by immunoblotting and characterization of immunoglobulins as antilipid autoantibodies. Setting: Intensive care unit of a university hospital and two research university laboratories. Subjects: Twenty-seven mechanically ventilated patients in total, including nine patients with ARDS and two control groups. Interventions: Patients were ventilated with a mechanical ventilation mode. Six aliquots of 20-mL sterile normal saline at 37 degreesC were infused through the working channel of the bronchoscope. Measurements: Total protein, detection of IgG by electrophoresis followed by immunoblotting, and characterization of IgG by enzyme-linked immunosorbent assay using different lipids as target antigens. Main Results: Antiphospholipid autoantibodies are present in BAL fluid of ARDS patients. Among the phospholipids tested, phosphatidic acid and phosphatidylserine gave the most significant activity. The IgG fraction, purified from BAL fluids by affinity chromatography, gave the same pattern of binding as that of the BAL fluid. Conclusion: The presence of anti phospholipid autoantibodies in BAL fluid suggests involvement of autoimmune mechanisms in the pathogenesis of ARDS. Crit Care Med

Increased titres of anti-dsDNA antibodies, especially if of high avidity, are associated with renal exacerbations in patients with systemic lupus erythematosus (SLE). One of the most reliable assays to measure anti-dsDNA antibodies, the Farr assay, is believed to detect preferentially high avidity antibodies. Purified non-complexed monoclonal antibodies (mAbs) against nucleosomes, obtained from mice with SLE, are not reactive in the Farr assay, but can become so once complexed to nucleosomes, These Farr-positive, nucleosome containing, immune complexes were also able to bind in vivo to the glomerular basement membrane (GBM), predominantly via heparan sulphate (HS). To evaluate whether in SLE patients the same kind of immune complexes are responsible for Parr reactivity, IgG from serum or plasma was isolated under dissociating and physiological conditions. We observed that after purification under dissociating conditions, Farr reactivity was significantly decreased (P

The sequence Pro-Pro-Gly-Meth-Arg-Pro-Pro (PPGMRPP) is the major B-cell epitope of the Sm autoantigen. The aim of the present study was to evaluate the immune response against the native forms of Sm and U1RNP and immune mediated tissue injury after immunization with the sequence PPGMRPP anchored in five copies to a new type helicoid sequential oligopeptide carrier (SQC) formed by the repetitive Lys-Aib-Gly moiety, [(PPGMRPP)(5)SOC5]. Rabbits (n = 3) were immunized with 0.5 mg of (PPGMRPP)(5)SOC5 in complete Freud's adjuvant and boosted at days 26, 53, 99; control rabbits were immunized with the PPGMRPP alone (n = 3), phosphate buffered saline (PBS) (n = 1), SOC, alone (n = 1), a peptide at aminoacid (aa) position 158-177 of myelin basic protein (MBP aa 158-147) (n = 1) and three La/SSB autoantigen B-cell epitopes (n = 3). Antibodies to (PPGMRPP)(5)SOC5 were determined by enzyme linked immunosorbent assay (ELISA); precipitating anti-Sm and anti-U1RNP antibodies were detected by RNA precipitation and western blot on HeLa total cellular and nuclear extract and 12s sucrose gradient fraction of rat Liver extracts. High titres of anti-(PPGMRPP)(5)SOC5 antibodies not recognizing the native forms of Sm or U1RNP antigens were detected in the (PPGMRPP)(5)SOC5 immunized but not in the control animals. The sera of two (PPGMRPP)(5)SOC5 immunized but not of the control rabbits recognized a 67 kDa protein in HeLa nuclear extract, distinct from the 70 kDa U1RNP antigen. Diffuse and segmental increase of mesangeal matrix and cells, crescent formation, segmental glomerular necrosis, rarely massive subendothelial deposits occluding the lumen and C3 complement component in the mesangeal area were seen in the kidneys of one (PPGMRPP)(5)SOC5 immunized, but not of the remaining animals. In conclusion, the immune response induced by (PPGMRPP)(5)SOC5 was specific for the immunizing epitope but not for the native forms of Sm and U1RNP antigens, but it was associated with immune mediated kidney injury. (C) 2000 Academic Press. J Autoimmun

SUMMARYThe aim of this study was to investigate the immunogenicity of four synthetic peptides, representing linear B cell epitopes of the human La/SSB autoantigen: 145–164 aa (p1), 289–308 aa (p2), 301–318 aa (p3) and 349–364 aa (p4), in rabbits. New Zealand White rabbits were immunized with each of the above peptides attached in four copies on tetrameric sequential oligopeptide carriers (SOC) in duplicate. Control immunizations were also performed (one rabbit each, immunized with Freud's complete adjuvant alone or with the SOC carrier alone). Animals were bled at regular intervals and sera were analysed for anti-La/SSB activity by ELISA assays using as antigen the various synthetic peptides, as well as the whole La/SSB protein. Four months after the last immunization, the animals were killed and peripheral blood mononuclear and spleen cells were co-cultured with either the peptides, the SOC carrier, or 27 peptides, covering the entire length of the human La/SSB molecule (23 amino acids long, overlapping by eight residues to each other). A specific, IgG, anti-peptide antibody response was detected, initially directed against the priming peptide, and subsequently expanded to the other La/SSB synthetic peptides. The antibody titres remained high, even 4 months after the last immunization. Sera from rabbits immunized with either p2 or p3 reacted also with the whole La/SSB protein, as was demonstrated by ELISA and immunoblot assays. No reactivities against either Ro60 or Ro52 autoantigen were found. Rabbit spleen cell reacted not only with the epitope used for the immunization but also with other La/SSB peptides. Immunization of rabbits with the major human La/SSB B cell antigenic determinants, linked to SOC carrier, induces strong and sustained antibody and T cell responses against multiple epitopes of the human La/SSB protein. Thus, La/SSB B cell linear epitopes are probably capable also of functioning as T cell epitopes, in this experimental animal.

Acquired hemophilia, caused by autoantibodies against coagulation factor VIII, is usually treated with steroids, cyclophosphamide, intravenous gammaglobulins and sporadically other drugs. We describe the case of a patient in whom the common therapeutic choice was unsuccessful, but cyclosporine proved to be effective.

SUMMARY Vascular injury in vasculitis may be due to activation of circulating neutrophils resulting in their increased adhesiveness to locally activated endothelium (Shwartzman phenomenon). Previously, we demonstrated up-regulation of endothelial intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in biopsies from patients with ANCA-associated vasculitis. In the present study, we investigated the expression of adhesion molecules (CD11b, ICAM-1, VLA-4, l-selectin) and activation markers (CD66b, CD64, CD63) on circulating neutrophils from patients with ANCA-associated vasculitis in comparison with their expression on cells from healthy volunteers and patients with sepsis. We related these findings to parameters of disease activity. Surface marker expression was determined by using a non-activating whole blood flow cytometric assay. The expression of activation markers, but not the expression of adhesion molecules, was increased on neutrophils from patients with active vasculitis. The expression of CD63 and CD66b on neutrophils correlated with disease activity as determined by the Birmingham Vasculitis Activity Score (BVAS). In contrast to patients with active vasculitis, patients with sepsis showed up-regulation of all markers, including adhesion molecules, suggesting that circulating neutrophils are fully activated in sepsis. We conclude that in ANCA-associated vasculitis, circulating neutrophils are not fully activated, since they do not express increased levels of adhesion molecules as sepsis or in the Shwartzman reaction. These findings are compatible with the concept that in vivo vascular damage in ANCA-associated vasculitides does not occur due to a Shwarzman-like reaction but only after ANCA-induced neutrophil activation at the endothelial cell surface.

PURPOSE: The clinical significance of antineutrophil cytoplasmic autoantibodies (ANCA) in primary sclerosing cholangitis has not been established. We investigated whether analysis of the antigenic specificities of ANCA is useful for delineating clinical subsets of the disease. METHODS: Sixty-nine patients with primary sclerosing cholangitis were studied. The presence of ANCA was analyzed by indirect immunofluorescence. Antibodies directed against specific antigens-proteinase 3, myeloperoxidase, elastase, bactericidal/permeability-increasing protein, cathepsin G, and lactoferrin-were identified by enzyme-linked immunosorbent assay. RESULTS: ANCA were detected by indirect immunofluorescence in 46 (67%) patients. In antigen-specific enzyme-linked immunosorbent assays, 37 (55%) of the 69 patients had antibodies to one or more antigens: 32 (46%) had antibodies to bactericidal/permeability-increasing protein, 16 (23%) had antibodies to cathepsin G, and 15 (22%) had antibodies to lactoferrin. Only 3 patients had antibodies to proteinase 3. Antibodies to myeloperoxidase or elastase were not detected. Twenty (29%) patients had antibodies to different antigens simultaneously. ANCA as detected by indirect immunofluorescence were not significantly associated with the presence of cirrhosis nor with the coexistence of inflammatory bowel disease. However, antibodies to bactericidal/permeability-increasing protein and cathepsin G were both associated with the presence of cirrhosis, and antibodies to lactoferrin were more frequently detected in patients with primary sclerosing cholangitis in conjunction with ulcerative colitis than in those without inflammatory bowel disease. CONCLUSION: Defined specificities of ANCA in primary sclerosing cholangitis may be related to particular clinical features of the disease. (C) 1998 by Excerpta Medica, Inc.

SUMMARY The B cell epitope mapping of La/SSB was performed using 20 mer synthetic peptides overlapping by eight amino acids covering the whole sequence of the protein. IgG, purified from sera of five patients with systemic lupus erythematosus (SLE) and four sera from patients with primary Sjögren's syndrome (pSS) were tested against the overlapping synthetic peptides. Peptides highly reactive with purified IgG were those spanning the regions 145–164, 289–308, 301–320 and 349–368 of the La protein. Determination of the minimum required length of the antigenic determinants disclosed the following epitopes:147HKAFKGSI154, 291NGNLQLRNKEVT302, 301VTWEVLEGEVEKEALKKI318 and 349GSGKGKVQFQGKKTKF364. Predicted features and molecular similarities of the defined epitopes were investigated using protein databases. The La epitope 147HKAFKGSI154 presented 83.3% similarity with the 139HKGFKGVD146 region of human myelin basic protein (MBP) and 72% similarity with the fragment YKNFKGTI of human DNA topoisomerase II. Peptides corresponding to these sequences cross-reacted with anti-La/SSB antibodies. Sixty-three sera with anti-La/SSB antibodies from patients with pSS or SLE, 35 sera without anti-La/SSB antibodies from patients with SS or SLE and 41 sera from age/sex-matched healthy blood donors were tested against biotinylated synthetic epitope analogues in order to determine their sensitivity and specificity for the detection of anti-La/SSB antibodies. Anti-La/SSB were detected with various frequencies ranging from 20% to epitope 147HKAFKGSI154 to 100% to epitope 349GSGKGKVQGKKTKF364. The overall sensitivity and specificity using all assays with the synthetic peptides were found to be 93.6% and 85.6%, respectively. In conclusion, antibodies to La/SSB constitute a heterogeneous population, directed against different linear B cell epitopes of the molecule. The epitope 147HKAFKGSI154 presents molecular similarity with fragments of two other autoantigens, i.e. human MBP and DNA topoisomerase II. Finally, synthetic epitope analogues exhibit high sensitivity and specificity for the detection of anti-La/SSB antibodies.

The primary vasculitides are diseases of unknown aetiology. They are characterized by inflammation of blood vessel walls, Measuring non-specific laboratory markers of inflammation is useful in the monitoring of patients with vasculitis. The diagnostic specificity of these markers is, however, restricted. In the last decade, autoantibodies reacting with myeloid granule proteins have been detected in the sera from patients with Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome, and the renal limited form of these vasculitides (i.e. idiopathic rapidly progressive glomerulonephritis). Anti-neutrophil cytoplasmic antibodies (ANCA) in the aforementioned disorders react with proteinase 3 (Pr3) or myeloperoxidase (MPO), and only incidentally to other antigens such as elastase and bactericidal-permeability increasing protein, The presence of ANCA alone, in particular perinuclear ANCA, as detected by indirect immunofluorescence, has a low specificity for those vasculitides, However, in combination with the presence of anti-Pr3 or anti-MPO antibodies as detected by enzyme-linked immunosorbent assay, sensitivity and specificity for the vasculitides is high. Several in vitro and in vivo data have suggested a pathophysiological role for anti-Pr3 and anti-MPO in the associated disorders. Measuring levels of the autoantibodies seems useful for the follow-up of patients with these vasculitides. The sensitivity and specificity of rises in ANCA levels for ensuing relapses appears somewhat lower than previously suggested. Refinement of the assays, for example, by measuring subclasses and functional characteristics of the autoantibodies, may improve their value in monitoring patients with vasculitides.

Anti-Sm antibodies are usually considered highly specific for systemic lupus erythematosus (SLE), while anti-U1 RNP antibodies are found in high titers in patients with mixed connective tissue disease (MCTD). The sequence P-1-P-G-M-R-P-P-7, present in three copies in the Sm (U1-U6 RNA-protein complex) autoantigen, is an important functional domain of the antigenic determinants. The immunoreactivity of this proline-rich repetitive epitope was investigated by testing sera with various autoantibody specificities for reactivity against this epitope, as well as its conformational properties by means of 1D and 2D (1)HNMR spectroscopy. It was found that the P-P-G-M-R-P-P epitope is recognized mainly by anti-U1RNP and/or anti-Sm positive sera, but also by anti-Ro(SSA) (hY1RNA-protein complex) and anti-La(SSB) (hY1RNA-protein complex) positive sera, although these sera are negative for anti-U1RNP and anti-Sm. Conformational analysis of the proline-rich epitope in DMSO-d(6) solution obtained from lyophilized aqueous solution at pH 5 showed the presence of at least three conformers. The main conformer A (62%) is stabilized by an ionic interaction between the guanidinium and the C-terminal carboxylate groups, and the Pro(6)-Pro(7) peptide bond adopts the cis form. A type II beta-turn is also present in the N-terminal sequence (Pro(1)-Pro-Gly-Met(4)-) of this conformer. Conformer B (21%) is also stabilized by a similar ionic interaction, as in conformer A, while the NMR data indicate the absence of a folded structure in the N-terminal tetrapeptide of this conformer. Conformer C (17%) adopts a completely extended structure. The multiple conformers of the P-P-G-M-R-P-P may offer some explanation for the reactivity of sera with various autoantibody specificities against this epitope. (C) Munksgaard 1996. International Journal of Peptide and Protein Research

Anti-Ro60KD autoantibodies are commonly found in sera from patients with primary Sjogren's syndrome (SS) and systemic lupus erythematosus (SLE). In order to identify the epitopes of this autoantigen, 22-mer, synthetic peptides overlapping by eight residues, and covering the entire sequence of the Ro60KD autoantigen were prepared. Three groups of sera were evaluated according to their autoantibody specificities. The first group consisted of monospecific anti Ro60KD sera from four patients with SLE and one with SS, the second one was composed of anti-Ro60KD + anti-La(SSB)-positive sera from four patients with SS and the third group included three normal sera and one anti Ro52KD serum. It was found that sera from SLE patients interact with a common antigenic site spanning the sequence TKYKQRNGWSHKDLLRSHLKP (169-190) of the Ro60KD protein. On the other hand, sera from SS patients recognise the ELYKEKALSVETEKLLKYLEAV (211-232) region of this autoantigen. Determination of the minimal required peptide length for optimal antibody recognition showed that the defined epitopes can be shortened to the NGWSHKDLLR (175-184) and KALSVETEKLLKYLEAV (216-332) sequences respectively. Inhibition experiments using the Ro60KD antigen and soluble peptides corresponding to the 175-184 and 216-232 segments further confirmed the specific antibody binding. These results, although only a small number of sera were used, indicate that the Ro60KD autoantigen, which is not characterized by disease specificity, contains two discrete epitopes specifically recognized from SLE and SS patient sera. Finally, the sequence similarity of the NGWSHKDLLR (175-184) epitope with some of the HLA haplotypes, associated with anti-lie response, deserves to be noted. Eur J Clin Invest