Anti-centromere antibody positivity is an independent variable associated with salivary gland ultrasonography score in Sjögren's syndrome

Sjögren's syndrome (SS) is an autoimmune disease characterized by periductal lymphocytic infiltration of the salivary and lacrimal glands. SS also exhibits extra-glandular manifestations and specific autoantibodies. Salivary gland ultrasonography (SGUS) is a common procedure used to assess the severity of glandular involvement. However, the association between SGUS and extra-glandular lesions remains poorly understood. This study aimed to identify clinical indices, including disease activity, associated with glandular involvement using SGUS in patients with SS. We included 115 patients with SS and 90 without SS. Patients with SS had significantly higher ultrasonography (US) score than patients without SS. Multivariate analysis revealed focus score, Saxon test positivity, and anti-centromere antibody (ACA) positivity as independent variables associated with the US score in patients with SS. In addition, these results were similar to those obtained in patients with primary SS. Patients with SS and ACA positivity had higher US score and an increased prevalence of hyperechoic bands in the parotid glands and submandibular glands. In conclusion, this study indicated that ACA positivity is associated with the US score in patients with SS. These results suggest that US findings in patients with ACA positivity might show specific changes in the salivary glands, especially fibrosis.

Antigen-driven selection of antibodies against SSA, SSB and the centromere 'complex', including a novel antigen, MIS12 complex, in human salivary glands

OBJECTIVES

Recent evidences have revealed that anti-SSA/SSB antibodies, the major autoantibodies in Sjögren's syndrome (SS), are produced in salivary glands. This study aims to clarify overall of autoantibody production at lesion site, including anti-centromere antibody (ACA)-positive SS.

METHODS

Antibodies of antibody-secreting cells in human salivary glands were produced as recombinant antibodies. The reactivity of these antibodies and their revertants were investigated by ELISA and newly developed antigen-binding beads assay, which can detect conformational epitopes. The target of uncharacterised antibodies was identified by immunoprecipitation and mass spectrometry. Autoantibody-secreting cells in salivary gland tissue were identified by immunohistochemistry using green fluorescent protein-autoantigen fusion proteins.

RESULTS

A total of 256 lesion antibodies were generated, and 69 autoantibodies including 24 ACAs were identified among them. Beads assay could detect more autoantibodies than ELISA, suggesting autoantibodies target to antigens with native conformation. After somatic hypermutations were reverted, autoantibodies drastically decreased antigen reactivity. We showed that MIS12 complex, a novel target of ACA, and CENP-C are major targets of ACA produced in salivary glands by examining cloned antibodies and immunohistochemistry, whereas few anti-CENP-B antibodies were detected. The target profiling of serum ACA from 269 patients with SS, systemic sclerosis (SSc), primary biliary cirrhosis (PBC) and healthy controls revealed that ACA-positive patients have antibodies against various sites of centromere complex regardless of disease.

CONCLUSION

We showed direct evidences of antigen-driven maturation of anti-SSA/SSB antibody and ACA in SS lesion. ACA recognises centromere 'complex' rather than individual protein, and this feature is common among patients with SS, SSc and PBC.

Recurrent post-partum rhombencephalitis associated with anti-centromere antibody: a case report

Background

Rhombencephalitis (RE) is a serious condition of the brain with multiple etiologies. We report a unique case of recurrent, postpartum RE that is associated with positive anti-centromere antibody (ACA). A discussion of the case, current literature on autoimmune RE and related autoantibodies are reviewed.

Case presentation

A healthy 33-year-old Caucasian patient (gravida 2, para 2) had two episodes of progressive focal neurological deficits during postpartum periods. Signs and symptoms included right-sided dysmetria, adiadochokinesia, weakness, ataxia, and photophobia. MRI revealed rhombencephalitis involving the mesencephalon of the brainstem. Extensive and comprehensive investigations using blood and cerebrospinal fluid (CSF) were consistently positive only for ACA. The first episode was successfully treated with empiric antimicrobial agents and steroid. Given the negative infectious work up with the prior episode and the nearly identical clinical presentations, the second episode was treated with corticosteroid only. This led to complete resolution of her symptoms and reversal of the brain magnetic resonance imaging (MRI) lesions.

Conclusion

To the author's knowledge, this is the first report of a primary autoimmune RE during postpartum period that is associated with ACA. Immunologic causes should be considered early with any encephalitis. Given the risk of recurrence, relapse, and neurologic deterioration, regular monitoring is recommended, especially for female patients of child-bearing age. Consistent with the current literature on autoimmune RE, steroid seems to be an effective treatment for ACA-associated RE.

Clinical Manifestation and Incidence of Cardiopulmonary Complications in Early Systemic Sclerosis Patients with Different Antibody Profiles

Background

There has been no prior inception cohort study comparing clinical manifestations and incidence rate (IR) of cardiopulmonary involvement among early systemic sclerosis (SSc) patients by difference in autoantibody profiles. We compared the differences in the clinical presentation at study entry and cumulative organ complications at last visit, as well as the IR of cardiopulmonary complications between anti-topoisomerase I antibody-positive SSc patients (pATA), ATA-negative (nATA), and the positive anti-centromere antibody patients (pACA).

Methods

An inception cohort of early diagnosis SSc patients (disease duration ≤ 3 years) seen at the Rheumatology Clinic, Maharaj Nakorn Chiang Mai Hospital, between January 2010 and June 2016, was studied. SSc patients who had follow-up duration as less than 1 year and those diagnosed with an overlap syndrome were excluded. All participants underwent electrocardiography (ECG), echocardiography, and high-resolution computed tomography (HRCT) at the study entry and then annually.

Results

A total of 114 patients (90 diffuse cutaneous SSc (dcSSc), 69 women) with mean (standard deviation, SD) disease duration of 11.7 (8.8) months at cohort entry and an observational period of 3.8 (1.6) years, were recruited. There were 89 patients (78.1%) with pATA, 18 (15.8%) with nATA, and 7 (6.1%) with pACA. At enrollment, both pATA and nATA groups had a higher prevalence of dcSSc subtype, and interstitial lung disease (ILD) when compared with the pACA group. At the last visit, the pATA group had a higher cumulative prevalence of digital ulcers, joint contracture and tendon friction rub than the other groups. Both the pATA and nATA groups had a significantly higher IR of ILD compared to the pACA group (54.9 and 57.8 vs. 6.3 per 100 person-years). During the study period, no suspected myositis, systolic pulmonary artery pressure (sPAP) ≥ 50 mm Hg or cardiac complications was observed in the pACA group.

Conclusions

In our study cohort, the majority of which were dcSSc subtype with pATA, it was found that the presence of SSc-specific autoantibodies was associated with a distinctive clinical presentation and cumulative internal organ involvement, even in the early phase of the disease. Cardiopulmonary complications were rarely seen in the pACA group; whereas ILD complications were very common in both the pATA and nATA groups. A further study into the association of autoantibodies in nATA patients with ILD complications is needed.

Clinical and Immunological Features of Anti-centromere Antibody-Positive Primary Sjögren's Syndrome

INTRODUCTION

Anti-centromere antibody (ACA)-positive Sjögren's syndrome (SS) is considered a subtype of SS. ACA-positive SS patients display several features, such as Raynaud's phenomenon, sclerodactyly, and extraglandular dysfunction. However, information on the features of ACA-positive SS is insufficient and the clinical significance of ACA in SS has not been fully established. The aim of this study was to clarify the features of ACA-positive SS.

METHODS

All patients with primary SS who visited our hospital were enrolled. Clinical information and immunological tests were collected and statistically analyzed.

RESULTS

A total of 585 patients were classified as having primary SS. They were divided into four groups by serum ACA and anti-SS-A antibody status as follows: 22 had ACA only (ACA alone), 464 had anti-SS-A antibodies only (SS-A alone), 26 had both ACA and anti-SS-A antibodies (double-positive), and 73 had neither ACA nor anti-SS-A antibodies (seronegative). The proportion of patients with dryness did not differ between the four groups. The proportion of patients with Raynaud's phenomenon or sclerodactyly was higher in the ACA alone and double-positive groups. The proportion of patients with increased serum IgG or IgA was 0 and 5% in the ACA alone group, 61 and 20% in the SS-A alone group, 52 and 28% in the double-positive group, and 20 and 4% in the seronegative group (p < 0.01 and p < 0.01), respectively. The proportion of patients with leukocytopenia was significantly lower in the SS-A-negative group than in the other groups.

CONCLUSIONS

Our study identified characteristics of ACA-positive SS patients that differ from those of anti-SS-A antibody-positive SS patients.