POS0869 CYTOKINES IN SYSTEMIC SCLEROSIS RELATED INTERSTITIAL LUNG DISEASE AND IDIOPATHIC PULMONARY FIBROSIS

Background

Immune pathways have been implicated in both systemic sclerosis (SSc)-related interstitial lung disease (ILD) and idiopathic pulmonary fibrosis (IPF). Determination of blood cytokine differences in these two disorders need to be elucidated to better understand potential biological processes and common pathogenic pathways.

Objectives

This study compared 87 circulating cytokine levels amongst healthy controls and both SSc-ILD and IPF. There was also exploration of the association between cytokine levels and disease progression based on the annualized rate of decline of forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO).

Methods

Levels of 87 plasma cytokines were measured using commercial panels for consecutive SSc-ILD, IPF, and healthy individuals recruited at a Canadian tertiary-care center. Pulmonary function tests were performed as clinically indicated every 3-12 months. Cytokine levels are compared using the Wilcoxon rank sum test for two samples pairwise. The association between differentially expressed cytokines with both percent predicted annualized FVC and DLCO change was assessed within each disease group using multiple linear models adjusted for age, sex, baseline FVC, and immunosuppressive or anti-fibrotic treatment at sampling. Correction for multiplicity of testing was by Holm’s method.

Results

There were 19 healthy controls, 40 SSc-ILD, and 17 IPF participants with clinical features shown in Table 1. Eotaxin-1 and interleukin 6 (IL-6) were significantly elevated in both SSc-ILD and IPF compared to healthy controls (Figure 1). SSc-ILD had significantly lower soluble epidermal growth factor receptor (sEGFR) and higher levels of both soluble tumor necrosis factor receptor type II (sTNFRII) and soluble vascular endothelial growth factor receptor-1 (sVEGFR1) compared to healthy controls. IPF cases were distinguished from healthy controls by significantly higher monocyte chemoattractant protein-1 (MCP-1) and monokine induced by gamma interferon (MIG, also known as CXCL9) levels. No significant association was found for any of the cytokines with ILD progression based on annualized rates of either FVC or DLCO change.

Table 1.

Baseline patient characteristics stratified by disease groups

Healthy control(n = 19)SSc-ILD(n = 40)IPF(n = 17)Age, year51 ± 1956 ± 1273 ± 7Male, count (%)6 (32)12 (30)12 (71)Disease duration, yearNA6.41 (7.81)1.76 (2.14)Ever smoker, count (%)2 (11)19 (48)14 (82)•4 (82)oker0.4 [0, 1]11 [4, 29]19 [11, 35]Treatment presence, count (%)NA16 (40)7 (41)Baseline FVC %NA80 ± 2285 ± 21Baseline DLCO %NA51 ± 1749 ± 11Annualized FVC % changeNA-1.7 ± 8.2-6.2 ± 13.6Annualized DLCO % changeNA-0.5 ± 6.2-7.8 ± 18.6

The number (%), mean ± standard deviation, and median [interquartile range] are shown. Disease duration is defined as time of ILD first seen on HRCT in IPF and time from first non-Raynaud’s phenomenon in SSc-ILD. Treatment includes presence of ILD therapies: nintedanib, pirfenidone, mycophenolate mofetil, azathioprine, rituximab. FVC = forced vital capacity, DLCO = diffusing capacity for carbon monoxide

Figure 1.

Notched box plots of cytokine differences between disease groups. All cytokine levels are shown on a log scale. Overlap of notches indicates lack of a statistically significant difference in medians in a pairwise comparison. P-values are for SSc-ILD or IPF compared to healthy controls using Wilcoxon rank sum two-sample test corrected for multiple testing using Holms method.

Conclusion

Differences in seven circulating cytokines between healthy controls with both SSc-ILD and IPF show evidence of systemic cytokine activation. All seven cytokines have a role in immune cell extravasation and pro-fibrotic signaling, which provides further evidence of immune pathways involved in pulmonary fibrosis. Further studies will be pursued of longitudinal change of these biomarkers for halting or slowing disease progression and improving response to treatment.

Disclosure of Interests

Boyang Zheng: None declared, Kevin Keen Grant/research support from: Merck Canada Inc, Marvin Fritzler Shareholder of: Abbott Laboratories; Roche Holdings; Abcellera; Moderna, Speakers bureau: For diagnostic company: Werfen, Consultant of: For diagnostic company: Werfen; Aesku, Employee of: Medical Director of Mitogen Diagnostics, Christopher Ryerson Speakers bureau: Boehringer Ingelheim, Hoffmann-La Roche, Consultant of: Boehringer Ingelheim, Hoffmann-La Roche, Veracyte, Astra Zeneca, Grant/research support from: Boehringer Ingelheim, Hoffmann-La Roche, Pearce Wilcox Speakers bureau: Vertex, Valeo, Boehringer, Beth Whalen: None declared, Basak Sahin: None declared, Haiyan Hou Employee of: Mitogen Diagnostics, Penny Latham Employee of: Eve technologies, Mei Feng Zhang Employee of: Mitogen diagnostics, Iris Yao: None declared, James Dunne: None declared

THU0271 PERFORMANCE OF THE EULAR/ACR 2019 CLASSIFICATION CRITERIA FOR SYSTEMIC LUPUS ERYTHEMATOSUS IN EARLY DISEASE, ACROSS SEXES AND ETHNICITIES

Background:

EULAR/ACR 2019 SLE Classification Criteria were validated in an international cohort.

Objectives:

To evaluate performance characteristics of SLE classification systems in sex, race/ethnicity, and disease duration subsets.

Methods:

Sensitivity and specificity of the EULAR/ACR 2019, SLICC 2012 and ACR 1982/1997 criteria were evaluated in the validation cohort.

Results:

The cohort consisted of female (n=1098), male (n=172), Asian (n=118), Black (n=68), Hispanic (n=124) and White (n=941) patients; and patients with an SLE duration of 1-3 years (n=196), 3-5 years (n=157), and ≥5 years (n=879). Among patients with 1-3 years disease duration, the EULAR/ACR criteria had better sensitivity than the ACR criteria (97% (95%CI 92-99%) vs 81% (95%CI 72-88%). The new criteria performed well in men (sensitivity 93%, specificity 96%) and women (sensitivity 97%, specificity 94%). The new criteria had better sensitivity than the ACR criteria in White (95% vs 83%), Hispanic (100% vs 86%) and Asian patients (97% vs 77%).

Conclusion:

The EULAR/ACR 2019 criteria perform well in patients with early disease, and across sexes and ethnicities.

Disclosure of Interests:

Sindhu Johnson Grant/research support from: Boehringer Ingelheim, Corbus Pharmaceuticals, GlaxoSmithKline, Roche, Merck, Bayer, Consultant of: Boehringer Ingelheim, Ikaria, Ralph Brinks: None declared, Karen Costenbader Grant/research support from: Merck, Consultant of: Astra-Zeneca, David Daikh: None declared, Marta Mosca: None declared, Rosalind Ramsey-Goldman: None declared, Josef S. Smolen Grant/research support from: AbbVie, Eli Lilly, Janssen, Merck Sharp & Dohme, Pfizer, Roche – grant/research support, Consultant of: AbbVie, Amgen Inc., AstraZeneca, Astro, Celgene Corporation, Celtrion, Eli Lilly, Glaxo, ILTOO, Janssen, Medimmune, Merck Sharp & Dohme, Novartis, Pfizer, Roche, Samsung, Sanofi, UCB – consultant, Speakers bureau: AbbVie, Amgen Inc., AstraZeneca, Astro, Celgene Corporation, Celtrion, Eli Lilly, Glaxo, ILTOO, Janssen, Medimmune, Merck Sharp & Dohme, Novartis, Pfizer, Roche, Samsung, Sanofi, UCB – speaker, David Wofsy: None declared, Dimitrios Boumpas Grant/research support from: Unrestricted grant support from various pharmaceutical companies, Diane L Kamen Consultant of: Consulted on SLE survey development for Lilly and consulted on SLE trial protocol development for EMD Serono in 2019, David Jayne Grant/research support from: ChemoCentryx, GSK, Roche/Genentech, Sanofi-Genzyme, Consultant of: Astra-Zeneca, ChemoCentryx, GSK, InflaRx, Takeda, Insmed, Chugai, Boehringer-Ingelheim, Ricard Cervera: None declared, Nathalie Costedoat-Chalumeau Grant/research support from: UCB to my institution, Betty Diamond: None declared, Dafna D Gladman Grant/research support from: AbbVie, Amgen Inc., BMS, Celgene Corporation, Janssen, Novartis, Pfizer, UCB – grant/research support, Consultant of: AbbVie, Amgen Inc., BMS, Celgene Corporation, Janssen, Novartis, Pfizer, UCB – consultant, Bevra H. Hahn Grant/research support from: Janssen Research & Development, LLC, Falk Hiepe: None declared, Soren Jacobsen: None declared, Dinesh Khanna Shareholder of: Eicos Sciences, Inc./Civi Biopharma, Inc., Grant/research support from: Dr Khanna was supported by NIH/NIAMS K24AR063120, Consultant of: Acceleron, Actelion, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Corbus Pharmaceuticals, Horizon Therapeutic, Galapagos, Roche/Genentech, GlaxoSmithKline, Mitsubishi Tanabe, Sanofi-Aventis/Genzyme, UCB, Kirsten Lerstrom: None declared, Elena Massarotti: None declared, William Joseph McCune: None declared, Guillermo Ruiz-Irastorza: None declared, Jorge Sanchez-Guerrero: None declared, Matthias Schneider: None declared, Murray B Urowitz: None declared, George Bertsias Grant/research support from: GSK, Consultant of: Novartis, Bimba F. Hoyer: None declared, Nicolai Leuchten: None declared, Chiara Tani: None declared, Sara Tedeschi: None declared, Zahi Touma: None declared, Gabriela Schmajuk Grant/research support from: Pfizer, Branimir Anic: None declared, Florence Assan: None declared, Tak Chan: None declared, Ann E Clarke: None declared, Mary K. Crow: None declared, László Czirják Consultant of: Actelion, BI, Roche-Genentech, Lilly, Medac, Novartis, Pfizer, Bayer AG, Andrea Doria Consultant of: GSK, Pfizer, Abbvie, Novartis, Ely Lilly, Speakers bureau: UCB pharma, GSK, Pfizer, Janssen, Abbvie, Novartis, Ely Lilly, BMS, Winfried Graninger: None declared, Bernadett Halda-Kiss: None declared, Sarfaraz Hasni: None declared, Peter Izmirly: None declared, Michelle Jung: None declared, Gabor Kumanovics Consultant of: Boehringer, Teva, Speakers bureau: Roche, Lilly, Novartis, Xavier Mariette: None declared, Ivan Padjen: None declared, Jose M Pego-Reigosa: None declared, Juanita Romero-Diaz Consultant of: Biogen, Iñigo Rua-Figueroa: None declared, Raphaèle Seror Consultant of: BMS, Medimmune, Novartis, Pfizer, GSK, Lilly, Georg Stummvoll: None declared, Yoshiya Tanaka Grant/research support from: Asahi-kasei, Astellas, Mitsubishi-Tanabe, Chugai, Takeda, Sanofi, Bristol-Myers, UCB, Daiichi-Sankyo, Eisai, Pfizer, and Ono, Consultant of: Abbvie, Astellas, Bristol-Myers Squibb, Eli Lilly, Pfizer, Speakers bureau: Daiichi-Sankyo, Astellas, Chugai, Eli Lilly, Pfizer, AbbVie, YL Biologics, Bristol-Myers, Takeda, Mitsubishi-Tanabe, Novartis, Eisai, Janssen, Sanofi, UCB, and Teijin, Maria Tektonidou Grant/research support from: AbbVie, MSD, Novartis and Pfizer, Consultant of: AbbVie, MSD, Novartis and Pfizer, Carlos Vasconcelos: None declared, Edward Vital Grant/research support from: AstraZeneca, Roche/Genentech, and Sandoz, Consultant of: AstraZeneca, GSK, Roche/Genentech, and Sandoz, Speakers bureau: Becton Dickinson and GSK, Daniel J Wallace: None declared, Sule Yavuz: None declared, Pier Luigi Meroni: None declared, Marvin Fritzler: None declared, Raymond Naden: None declared, Thomas Dörner Grant/research support from: Janssen, Novartis, Roche, UCB, Consultant of: Abbvie, Celgene, Eli Lilly, Roche, Janssen, EMD, Speakers bureau: Eli Lilly, Roche, Samsung, Janssen, Martin Aringer Consultant of: Boehringer Ingelheim, Roche, Speakers bureau: Boehringer Ingelheim, Roche

AB0511 INTERNATIONAL CONSENSUS ON ANCA TESTING AND INTERPRETATION BEYOND SYSTEMIC VASCULITIS

Background:

ANCA can be detected in sera from patients with autoimmune, inflammatory, infectious or neoplastic diseases.

Objectives:

To issue a Consensus Statement on ANCA testing and interpretation beyond systemic vasculitis.

Methods:

This Statement was prepared by a group of experts, based on the results of a comprehensive search in PubMed.

Results:

In certain settings beyond systemic vasculitis, ANCA may have diagnostic, clinical, and/or prognostic relevance. Testing for PR3- and MPO-ANCA by specific immunoassays should be performed in any patient with clinical features suggesting ANCA-associated vasculitis and in patients with anti-GBM disease and idiopathic interstitial pneumonia. Routine ANCA testing is not recommended in patients with connective tissue diseases (CTD), autoimmune liver diseases, inflammatory bowel diseases, infections, and/or malignancy unless there is evidence for small vessel vasculitis. ANCA testing by specific immunoassays may be useful in patients with rheumatoid arthritis, systemic sclerosis or primary Sjögren’s syndrome who have kidney disease with a nephritic sediment or in patients with systemic lupus erythematosus if a kidney biopsy shows prominent necrotizing and crescentic lesions or proliferative lupus nephritis. ANCA testing may be justified in patients with suspected autoimmune hepatitis type 1, who do not have conventional disease-related autoantibodies, or in patients with inflammatory bowel diseases in case of diagnostic uncertainty to discriminate ulcerative colitis from Crohn’s disease. In these cases, ANCA should be tested by indirect immunofluorescence since target antigens are not well characterized. ANCA against bactericidal/permeability-increasing protein may be a biomarker for deteriorating lung function and a poor prognosis in patients with cystic fibrosis.

Conclusion:

ANCA testing is clinically relevant not only in patients with manifestations suggesting systemic vasculitis, but also in patients with certain other disorders, particularly in patients with anti-GBM disease or idiopathic interstitial pneumonia.

Disclosure of Interests:

Sergey Moiseev Grant/research support from: This work was supported by the 5-100 Project, Sechenov University, Moscow, Jan Willem Cohen Tervaert: None declared, Yoshihiro Arimura: None declared, Dimitrios Bogdanos: None declared, Csernok Elena: None declared, Jan Damoiseaux: None declared, Marc Ferrante: None declared, Luis Felipe Flores-Suárez: None declared, Marvin Fritzler: None declared, Pietro Invernizzi: None declared, David Jayne Grant/research support from: ChemoCentryx, GSK, Roche/Genentech, Sanofi-Genzyme, Consultant of: Astra-Zeneca, ChemoCentryx, GSK, InflaRx, Takeda, Insmed, Chugai, Boehringer-Ingelheim, J. Charles Jennette: None declared, Mark Little: None declared, Stephen P. McAdoo: None declared, Pavel Novikov Grant/research support from: This work was supported by the 5-100 Project, Sechenov University, Moscow, Charles D. Pusey: None declared, Antonella Radice: None declared, Alan D. Salama: None declared, Judith Savige: None declared, Mårten Segelmark: None declared, Yehuda Shoenfeld: None declared, Renato Alberto Sinico: None declared, Maria Jose Rego de Sousa: None declared, Ulrich Specks: None declared, Benjamin Terrier: None declared, Athanasios Tzioufas: None declared, Severine Vermeire: None declared, Ming-hui Zhao: None declared, Xavier Bossuyt: None declared

Mammalian target of rapamycin is activated in the kidneys of patients with scleroderma renal crisis

Objectives:

Scleroderma renal crisis is a rare but serious complication affecting 2%–15% of patients with systemic sclerosis. Despite treatment with angiotensin-converting enzyme inhibitors, outcomes for scleroderma renal crisis patients are still poor. The cellular signaling mechanisms in scleroderma renal crisis are not yet known. Mammalian target of rapamycin, comprised of the subunits mTORC1 and mTORC2, has been shown to be activated in vascular lesions of renal transplant patients with anti-phospholipid antibody syndrome. Given the similarities between the pathophysiology of scleroderma renal crisis and anti-phospholipid antibody syndrome, we hypothesized that the mammalian target of rapamycin pathway would also be activated in the renal vasculature of patients with scleroderma renal crisis.

Methods:

We retrospectively analyzed renal biopsies of five patients with scleroderma renal crisis in the Canadian Scleroderma Research Group cohort. Immunostaining was performed using anti-P-S6RP antibodies to evaluate the phosphorylation of mTORC1, and anti-Rictor and anti-S473 to determine activation of mTORC2.

Results:

Four of the five patients showed mTORC1 activation in arteriolar endothelial cells, and three of the five patients showed mTORC1 activation in the arterial endothelial cells. Two of four samples showed Rictor expression in the arteriolar and arterial endothelial cells, showing mTORC2 activation. There was no expression of mTORC1 or mTORC2 in samples from two healthy controls.

Conclusion:

We demonstrate that both mTORC1 and mTORC2 are activated in renal biopsies with typical histologic features of scleroderma renal crisis. Dual mammalian target of rapamycin inhibitors are currently available and in development. These findings could inform further research into novel treatment targets for scleroderma renal crisis.

CCL22 is a biomarker of cartilage injury and plays a functional role in chondrocyte apoptosis

BACKGROUND

Osteoarthritis (OA) is one of the leading causes of disability worldwide. Previous history of knee injury is a significant risk factor for OA. It has been established that low-level chronic inflammation plays a pivotal role in the onset and pathogenesis of OA. The primary aim of this research was to determine if a history of knee joint injury is associated with systemic inflammation. A secondary aim was to determine if systemic inflammation is related to knee pain and joint structure.

METHODS

Differences in serum cytokine association networks, knee joint structural changes (MRI), and self-reported pain (i.e., Knee Injury and Osteoarthritis Outcome Score Pain subscale, KOOS_PAIN and Intermittent and Constant Osteoarthritis Pain score, ICOAP) between individuals who had sustained a youth (aged 15-26 years) sport-related knee injury 3-10 years previously and age- and sex-matched controls were examined. Proteins of interest were also examined in an OA rat model.

RESULTS

Cytokine association networks were found to differ significantly between study groups, yet no significant associations were found between networks and KOOS_PAIN or MRI-defined OA. A group of cytokines (MCP1/CCL2, CCL22 and TNFα) were differentially associated with other cytokines between study groups. In a pre-clinical rat OA model, serum CCL22 levels were associated with pain (r = 0.255, p = 0.045) and structural changes to the cartilage. CCL22 expression was also observed in human OA cartilage and furthermore, CCL22 induced apoptosis of isolated human chondrocytes.

DISCUSSION

These results suggest that CCL22 may be an early factor in the onset/pathogenic process of cartilage degeneration and/or related to pain OA.

Prevalence and clinical profiles of 'autoantibody-negative' systemic sclerosis subjects

OBJECTIVES

To determine the prevalence of autoantibody negative systemic sclerosis (SSc) and to identify the clinical correlates thereof.

METHODS

Clinical data and sera from 874 SSc subjects were collected and autoantibodies were tested in a central laboratory using 1) indirect immunofluorescence (IIF), 2) commercially available ELISA, addressable laser bead immunoassay (ALBIA), and line immunoassay (LIA), and 3) a sensitive immunoprecipitation (IP) assay.

RESULTS

Fifteen (15; 1.7%) subjects were autoantibody negative by IIF, ELISA, ALBIA, LIA and IP, and 16 (1.8%) were antinuclear antibody (ANA) positive by IIF but otherwise negative by ELISA, ALBIA, LIA and IP. Thirty-seven (37; 4.2%) were ANA positive by IIF, autoantibody negative by commercially available immunoassays, but had autoantibodies identified by IP (including Th/To in 20). Autoantibody-negative subjects had generally less severe disease than positive subjects.

CONCLUSIONS

Autoantibody-negative SSc is rare (<2%) and appears to be associated with a favourable prognosis.

A randomized unblinded trial of cyclophosphamide versus azathioprine in the treatment of systemic sclerosis

Current therapeutic modalities for the treatment of systemic sclerosis (SSc) have significant limitations. The window of opportunity to prevent tissue fibrosis and irreversible damage occurs during the early inflammatory phase of this condition. A drug that we believe has promise to exert a desired effect in early SSc is cyclophosphamide (CYC). However, there are only a few published reports regarding the use of cytotoxic immunosuppressive medications at the onset of the illness. The goal of this study was to test the efficacy and toxicity of CYC in patients with early diffuse SSc. The study design was a randomized, unblinded, 18 months per patient trial with a comparison group that received azathioprine (AZ). Thirty patients were assigned to receive oral CYC (2 mg/kg daily for 12 months and then maintained on 1 mg/kg daily) and 30 patients were assigned to receive oral AZ (2.5 mg/kg daily for 12 months and then maintained on 2 mg/kg daily). During first 6 months of the trial, the patients also received prednisolone, which was started at a dosage of 15 mg daily and tapered to zero by the end of the sixth month. After treatment there was a statistically significant improvement in the modified Rodnan skin score (MRSS), attack frequency of Raynaud's phenomenon (RP), and erythrocyte sedimentation rate (ESR) in the CYC-group, but not in the AZ-group. The forced vital capacity (FVC) and carbon monoxide diffusing capacity (DLCO) did not change after treatment in the CYC-group, but statistically significantly worsened in the AZ-group. No life-threatening or irreversible adverse reactions were observed in either group. This study showed that CYC is a promising disease modifying medication for SSc as it exhibited a positive influence on the evolution of disease.

ASE-1: an autoantigen in systemic lupus erythematosus

ASE-1 is a 55 kDa nucleolar autoantigen. We show that autoantibodies to this antigen occur at a higher frequency in the sera of patients with SLE than in other systemic rheumatic diseases and that the specificity of ASE-1 as a serum marker of SLE increases as the number of epitopes recognized by the sera increases. Autoantibodies to ASE-1 were temporally associated with autoantibodies to HsEg5 but were not found in conjunction with other known serum markers of SLE. The frequency of antibodies to ASE-1 epitopes in a SLE cohort was approximately the same as anti-dsDNA. However, anti-dsDNA is associated with renal involvement, whereas ASE-1 reactivity shows an association with a history of serositis. We conclude that ASE-1 is correlated with serositis and that ASE-1 should be added to a list of autoantigens that are considered important serological features of SLE.

Autoantibodies in childhood post-varicella acute cerebellar ataxia

BACKGROUND

Anti-Purkinje cell antibodies have been reported in cerebellar ataxia following Epstein-Barr virus (EBV) infection. We investigated autoantibody responses, including anti-Purkinje cell antibodies, and the clinical course in eight children who developed post-varicella ataxia, five of their siblings with uncomplicated varicella, one child with post-EBV ataxia, two children with acute disseminated encephalomyelitis (ADEM) and one with neuroblastoma associated ataxia, and in age and gender matched controls.

METHODS

Autoantibodies were tested by indirect immunofluorescence (IIF) on cryopreserved cerebrum and cerebellum sections. Other autoantibodies were measured by conventional IIF protocols using HEp-2 cells as a substrate. Antibodies to myelin associated glycoprotein (MAG), asialo-GM1, beta2 glycoprotein 1, cardiolipin and myelin basic protein (MBP) were measured by ELISA.

RESULTS

Three of eight children with acute post-varicella ataxia, one child with post-EBV ataxia, one child with ADEM and one child with uncomplicated varicella, had high titer autoantibodies (>1/160) that reacted with cerebrum and cerebellar tissue. This reactivity was not seen in one child with ADEM, in one with neuroblastoma and ataxia, in the remainder of the children with uncomplicated varicella or age and gender matched controls. Autoantibodies were not seen in CSF from two children with post-varicella ataxia. The punctate staining seen on cerebrum and cerebellum sections co-localized with rabbit antibodies to the centrosome protein pericentrin. All patients with strong reactivity with cerebrum and cerebellar tissue by IIF had elevated levels of anti-MAG that was not confirmed by absorption assay. No reactivity was seen with asialo-GM1, MBP, beta2 glycoprotein 1 or cardiolipin. None of the sera had autoantibodies directed against endosomes, the Golgi complex, or the paraneoplastic autoantigens Hu and Yo.

CONCLUSION

Some children with post-viral ataxia develop antibodies that have strong reactivity with cerebral and cerebellar tissue. Some of the antigenic reactivity co-localized with the centrosome protein pericentrin.

Expression of N-acetyl-D-galactosamine associated epitope in synovium: a potential marker of glycoprotein production

OBJECTIVE

To investigate synovial glycoprotein production in situ, a novel monoclonal antibody (Mab), A13D8, was used to evaluate the expression of an epitope containing N-acetyl-D-galactosamine (GalNAc) in normal and pathological synovium.

METHODS

Immunohistological and cytochemical analysis of synovial tissue samples was undertaken with single and double staining techniques using the A13D8 Mab, anti-CD68, vascular cell adhesion molecule-1 (VCAM-1), the hyaluronan associated enzyme uridine diphosphoglucose dehydrogenase (UDPGD), and the anti-Golgi Mab SSN/HR-1992. The specificity of the A13D8 Mab was established through blocking studies using carbohydrate residues, including GalNAc and N-acetylglucosamine (GlcNAc).

RESULTS

A13D8 is expressed intensely in the cytoplasm of normal type B lining cells, which coexpress VCAM-1 and UDPGD, and is not expressed by CD68+ type A lining cells. In the lining layer of RA synovium, there is a negative correlation between A13D8 expression and the level of lymphocytic infiltration in the sublining areas (r = -0.43, p < 0.001). The endothelium of a subset of venules, typically in lymphocyte-rich aggregates, also stains intensely for A13D8. Pretreatment of the Mab with GalNAc completely eliminates the tissue staining, as well as the 110 kDa band seen on immunoblot, whereas pretreatment of A13D8 with GlcNAc and lactose has no effect. Double staining of HEp-2 cells with A13D8 and the anti-Golgi Mab SSN/HR-1992 reveals co-localization of the A13D8 epitope to the Golgi apparatus.

CONCLUSION

Type B synovial lining cells and selected synovial endothelium express GalNAc containing epitope identified by Mab A13D8. Marked reduction in the expression of this epitope in the lining layer of inflamed RA synovium suggests that the synovial production of GalNAc containing glycoproteins, such as mucins, may be altered in this disorder.

An immunological renal disease in transgenic mice that overexpress Fli-1, a member of the ets family of transcription factor genes

The proto-oncogene Fli-1 is a member of the ets family of transcription factor genes. Its high expression in the thymus and spleen and the presence of DNA binding sites for Fli-1 in a number of lymphoid cell-specific gene suggest that Fli-1 is involved in the regulation of lymphopoiesis. Activation of the Fli-1 gene by either chromosomal translocation or viral insertion leads to Ewing's sarcoma in humans and erythroleukemia in mice, respectively. Thus, Fli-1 is normally involved in pathways involved in the regulation of cell growth and differentiation. We have generated H-2Kk-Fli-1 transgenic mice that overexpress Fli-1 in various mouse tissues, with the highest levels of Fli-1 protein in the thymus and spleen. These Fli-1 transgenic mice developed a high incidence of a progressive immunological renal disease and ultimately died of renal failure caused by tubulointerstitial nephritis and immune-complex glomerulonephritis. The incidences of renal disease correlated with the levels of Fli-1 protein in lymphoid tissues of transgenic lines. The hypergammaglobulinemia, splenomegaly, B-cell hyperplasia, accumulation of abnormal CD3+ B220+ T lymphoid cells and CD5+ B220+ B cells in peripheral lymphoid tissues, and detection of various autoantibodies in the sera of diseased Fli-1 transgenic mice suggested the involvement of an immune dysfunction in the pathogenesis of the renal disease. In addition, splenic B cells from transgenic mice exhibited increased proliferation and prolonged survival in vitro in response to mitogens. Taken together, these data suggest that overexpression or ectopic expression of Fli-1 perturbs normal lymphoid cell function and programmed cell death. Thus, H-2Kk-Fli-1 transgenic mice may serve as a murine model for autoimmune disease in humans, such as systemic lupus erythematosus.

Influence of Corynebacterium parvum-PER on disease progression in the NZB/W model of systemic lupus erythematosus

Murine models of systemic lupus erythematosus (SLE) exhibit some, but not all, of the characteristics of human disease. Disease progression in the animal models is regulated by autoantibodies, genetics and inflammatory processes. In the present study, the influence of the pyridine extract residue of Corynebacterium parvum Type I (CP-PER) on disease progression in the NZB/W model of SLE was investigated. CP-PER is known to activate the reticuloendothelial (RE) system of mice and can alter a number of host responses. Injection of NZB/W females with CP-PER at 10 weeks of age, prior to the onset of overt disease, led to a transient activation of the RE system which then appeared to return to levels observed in untreated animals. Sera from treated and untreated animals were analyzed for anti-nuclear antibodies, and anti-ssDNA antibodies. The most prominant change in the treated animals was an increase in the titer of anti-ssDNA. On average, animals in the early treatment group also lived somewhat longer than those in the untreated control group. Treatment of animals with CP-PER at 6 months of age, when the disease was evident, again led to transient RES activation and an altered autoantibody profile. Animals treated with CP-PER at 6 months of age exhibited a slightly accelerated death rate when compared with the untreated controls. These results indicate that bacterial response modifiers such as C. parvum-PER, which contains primarily the RES activating activity of C. parvum, can alter disease progression in the NZB/W model.

Plasma proteinase regulation during disease progression in murine models of SLE

Analysis of plasma proteinase during disease progression in murine models of systemic lupus erythematosus revealed three different patterns of regulation. Female NZB/W mice exhibited no age-dependent alterations in plasma proteinase activity from 3-9 months of age. Animals at nine months of age exhibited splenomegaly, high titers of serum autoantibodies and evidence of kidney disease, but no disruption of plasma proteinase activity. Male BxSB mice exhibited elevations in plasma proteinase activity as a late-onset (greater than 20 weeks of age) feature of the disease process. The onset of proteinase dysregulation occurred after significant mortality was evident and therefore variables associated with the induction of elevated levels of plasma proteinase activity are not related to early mortality factors. In contrast, female MRL-lpr mice exhibited age-dependent induction of elevated plasma proteinase activity which correlated temporally with the onset of mortality and the previously described reticuloendothelial system activation (Hart, J. Clin. Lab. Immunol., 26, 129). Interestingly, male MRL-lpr mice, which live slightly longer than female mice of the same strain, exhibited a delayed onset of plasma proteinase dysregulation. These results indicate that induction of changes in plasma proteinase regulation during the natural course of disease varies between these three murine models of SLE. Assessment of plasma proteinase regulation in human disease may reveal subpopulations of patients with features analogous to the murine models, which in turn could influence the choice of therapeutic modalities in disease management.

Raynaud syndrome in childhood

Twenty-seven patients with Raynaud syndrome (mean age at onset 11.7 years) were studied to determine the prevalence of primary Raynaud syndrome and to assess the predictive role of antinuclear antibody, nail-fold capillary microscopy, and photoelectric plethysmography in this population. Fourteen patients (52%) had a connective tissue disease, four (15%) had a probable connective tissue disease, and nine (33%) had primary Raynaud syndrome. In all patients with either a connective tissue disease or a probable connective tissue disease, there was a positive reaction to antinuclear antibody, in contrast to patients with primary Raynaud syndrome, in whom antinuclear antibody was not detected. Nail-fold capillary microscopy scores differed significantly between patients with either a connective tissue disease or a probable connective tissue disease and those with primary Raynaud syndrome for both enlarged loop score (p less than 0.025 and less than 0.05, respectively) and avascular score (p less than 0.005 and less than 0.01, respectively). Photoelectric plethysmography scores were reduced in all groups but did not differ significantly between groups. Our findings suggest that in children with Raynaud syndrome, the primary type is more common than was originally suspected, and that both antinuclear antibody and nail-fold capillary microscopy, but not photoelectric plethysmography, can distinguish patients with primary Raynaud syndrome from those with either a connective tissue disease or a probable connective tissue disease.

Evaluation of fetal cardiac dysrhythmias with two-dimensional, M-mode, and pulsed Doppler ultrasonography

Forty-three patients with fetal cardiac dysrhythmia were referred to a tertiary ultrasound department for further evaluation. The patients were subdivided according to the type of dysrhythmia diagnosed. All patients with irregular fetal heart rate had a good perinatal outcome. Of the six patients with fetal tachycardia, two required in utero therapy with maternal digoxin, and one of these fetuses had a cardiac tumor. The eleven patients with fetal bradycardia had the worst perinatal outcome, with four deaths occurring. The results suggest that all patients with fetal tachycardia or bradycardia should have a complete fetal cardiac assessment in a center experienced with the management of such cases.

A case of drug induced lupus due to carbamazepine

We report a case of drug induced lupus related to carbamazepine. Both clinical and serological data are described. This represents the first documented case of carbamazepine induced lupus erythematosus in the literature with serological confirmation.

Clinical features of systemic lupus erythematosus patients with antihistone antibodies

The presenting features of 25 systemic lupus erythematosus (SLE) patients with antihistone antibodies were compared to 25 age and sex matched patients who had antibodies to Sm, ribonuclear protein, Sjögren's syndrome antigen B and native DNA. The SLE patients with antihistone antibodies had a significantly lower frequency of renal disease, central nervous system disease, alopecia, anemia and hypocomplementemia. Nine of 25 (36%) age and sex matched RA patients had antihistone antibodies but in lower titers than the SLE patients. There was no correlation of antihistone antibody titers with disease activity, corticosteroid therapy or rheumatoid factor titer. Histone-antihistone complexes did not bind complement components of either the classical or alternative pathway of complement.