Publications by authors named "Stephen Adelstein"

36 Publications

Cerebrospinal fluid free light chain quantitation is a specific biomarker for inflammatory neurological disorders in a paediatric patient cohort.

Pathology 2021 Mar 18. Epub 2021 Mar 18.

Sydney Medical School, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia; Brain Autoimmunity Lab, Kids Neuroscience Centre, Kids Research, The Children's Hospital at Westmead, Westmead, NSW, Australia; T.Y. Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Westmead, NSW, Australia.

The analysis of cerebrospinal fluid (CSF) is routinely used in the diagnostic work-up of a range of inflammatory, infective, and congenital neurological conditions. Many diagnostic tests used in this analysis have poor sensitivity; as such, we investigated the utility of CSF free light chain (FLC) analysis as an adjunct to currently used assays in a paediatric population with neurological disorders. Kappa (κ) and lambda (λ) FLC levels were quantitated in blinded CSF samples by two nephelometric platforms. Results were correlated to clinical diagnoses and classified according to inflammatory/infective or non-inflammatory pathogenesis. FLC results were also compared to currently used CSF diagnostic tests including oligoclonal bands (OCB), CSF IgG and albumin levels, and differential cell count. Of 70 samples analysed, 29 (41%) had an inflammatory or infective diagnosis and 41 (59%) presented with a range of non-inflammatory aetiologies. Thirteen patients had elevated κFLC or λFLC as detected on the IMMAGE 800, defined as greater than the detection limit of the assay (0.600 mg/L for CSF κFLC, and 0.490 mg/L for CSF λFLC), and of these 12 (92%) had an inflammatory disease (sensitivity 41.4%, specificity 97.6%). On the BN II using optimal cut-offs of 0.27 mg/L and 0.12 mg/L for CSF κFLC and λFLC respectively, 24 (34%) patients had elevated results, of which 21 (88%) had an inflammatory disease (sensitivity 72.4%, specificity 92.7%). Analysis of FLC correlated better with diagnostic classification of the diseases than OCB, cell counts and CSF IgG levels. The results of this study support the use of CSF FLC analysis in the diagnosis of paediatric neuroinflammatory conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.pathol.2020.11.011DOI Listing
March 2021

Precision therapy for neuromyelitis optica spectrum disorder: A retrospective analysis of the use of class-switched memory B-cells for individualised rituximab dosing schedules.

Mult Scler Relat Disord 2020 Aug 11;43:102175. Epub 2020 May 11.

Neurology, Royal Prince Alfred Hospital (RPAH), Australia; Brain & Mind Centre, University of Sydney (USyd), Australia; Faculty of Medicine & Health, USyd, Australia. Electronic address:

Background: B-cell depleting treatments are widely used to modify the course of neuromyelitis optica spectrum disorder (NMOSD). Despite recent successful Phase 3 trials of several novel NMOSD therapies, limited availability and high cost constrains their clinical use, and rituximab (RTX) remains a core treatment in many centres. Since 2013, the Royal Prince Alfred Hospital Neuroimmunology Clinic (NIC) has regularly measured class-switched memory B-cells (SMB-cells) in the peripheral blood of patients with NMOSD, who have been treated with RTX, in order to guide retreatment intervals.

Objective: To assess the management and outcomes of the treated patients, and to determine the effect of SMB-cell monitoring in guiding retreatment intervals.

Methods: A retrospective analysis of hospital records, clinic letters and laboratory data was performed.

Results: Sixteen patients with NMOSD received individualised rituximab dosing at NIC between 2013 and 2018. Fourteen (87.5%) were aquaporin-4 antibody (AQP4-Ab) positive; 1 (6.25%) was myelin oligodendrocyte glycoprotein antibody (MOG-Ab) positive and 1 (6.25%) was seronegative. After commencement of RTX, individually dosed according to regular measurements of serum SMB-cells, there was a 77.5% reduction in annualised relapse rate over a mean follow-up time of 46.1 months in our recently active NMOSD patients. Their mean retreatment interval was 50.9 weeks.

Conclusions: This study provides real-world evidence supporting individualised rituximab dosing in the treatment of NMOSD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.msard.2020.102175DOI Listing
August 2020

Liver enzyme profile and progression in association with thyroid autoimmunity in Graves' disease.

Endocrinol Diabetes Metab 2019 Oct 15;2(4):e00086. Epub 2019 Jul 15.

Department of Endocrinology Royal Prince Alfred Hospital Camperdown New South Wales Australia.

Objective: To investigate the associations of Graves' disease (GD) severity, autoimmunity and longitudinal liver enzyme changes with time in a cohort with well-characterized GD.

Design: Retrospective cohort study.

Patients: Patients diagnosed with Graves' disease, treated at Royal Prince Alfred Hospital Sydney, Adult Thyroid Clinic from 2000 to 2012 inclusive.

Measurements: Inclusion criteria were patients with a complete set of TSH, FT4, FT3, liver enzymes and TSH receptor antibody (TRAb) results prior to commencement of thionamide therapy.

Results: Of the 146 patients who had complete results, 69 (47%) had at least one abnormal liver enzyme. Gamma glutamyltransferase (GGT) was most frequently abnormal (74%), followed by alanine aminotransferase (ALT) (57%), alkaline phosphatase (ALP) (39%) and then aspartate aminotransferase (AST) (29%). Subsequent to thyroid function normalization, 78% of the liver enzymes were normalized, 10% were persistently abnormal and 12% were lost to follow-up. Circulating TRAb, FT3 and FT4 results were categorized into mild, moderate and severe elevations. At univariate regression analyses, TRAb, FT3 and FT4 levels were each significantly associated with abnormal liver enzyme profile. Multivariate regression including TRAB, FT3 and FT4 as independent variables demonstrated FT3 and FT4 were more strongly associated with abnormal liver profile than TRAb. However, the initial FT3 and FT4 levels were not associated with abnormal liver profile in the subgroup with persistently abnormal liver profile.

Conclusion: Graves' disease is commonly associated with abnormal liver enzymes, and most commonly with abnormal levels of GGT, and that an abnormal liver enzyme profile is more directly linked to the degree of thyrotoxicosis than levels of TRAB.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/edm2.86DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6775470PMC
October 2019

Review: Serum biomarkers in idiopathic pulmonary fibrosis and systemic sclerosis associated interstitial lung disease - frontiers and horizons.

Pharmacol Ther 2019 10 31;202:40-52. Epub 2019 May 31.

Department of Respiratory, Royal Prince Alfred Hospital, Sydney, Australia; Sydney Medical School, University of Sydney, Australia.

Disease behaviour in interstitial lung disease (ILD) is highly variable and accurate clinical tools to predict prognosis and guide management decisions remain unsatisfactorily elusive. Accurate disease stratification would allow clinicians to better distinguish patients at risk of rapid progression requiring urgent treatment, from those indolent disease where potentially toxic drug therapy could be minimised or avoided. Several serum biomarkers have demonstrated potential utility for diagnosis and prognosis of ILD in small retrospective studies, and the hope is future multicentre prospective trials focussed on the markers with most potential will see translation to clinical practice. Two important and contrasting fibrotic lung diseases with high mortality are idiopathic pulmonary fibrosis (IPF) and systemic sclerosis associated ILD (SSc-ILD). In this era where anti-fibrotics for IPF have proven benefit, there are increasing biologic and non-biologic options for the treatment of connective tissue disease ILD (CTD-ILD), and the incidence of both is increasing, there is an urgent need to improve the diagnostic and prognostic accuracy in these complex patients. This comprehensive literature review will summarise and discuss the current evidence for the major candidate serum biomarkers in IPF and SSc-ILD. Biomarkers will be categorised by the following major mechanistic pathways (1) alveolar epithelial cell damage; (2) aberrant fibrogenesis, fibroproliferation and matrix remodelling; (3) immune dysregulation; and (4) vascular and endothelial damage. The aim is to review the rationale, potential and limitations of current candidate biomarkers and their utility in IPF and SSc-ILD to help direct future research and translation to clinical practice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.pharmthera.2019.05.014DOI Listing
October 2019

Hemophagocytic Lymphohistiocytosis in Loeys-Dietz Syndrome.

J Clin Immunol 2018 04 9;38(3):234-236. Epub 2018 Mar 9.

Discipline of Child and Adolescent Health, University of Sydney, Westmead, NSW, 2145, Australia.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10875-018-0484-0DOI Listing
April 2018

Role of Autoantibodies in the Diagnosis of Connective-Tissue Disease ILD (CTD-ILD) and Interstitial Pneumonia with Autoimmune Features (IPAF).

J Clin Med 2017 May 4;6(5). Epub 2017 May 4.

Department of Respiratory and Sleep Medicine, Royal Prince Alfred Hospital, Sydney, NSW 2050, Australia.

The diagnosis of interstitial lung disease (ILD) requires meticulous evaluation for an underlying connective tissue disease (CTD), with major implications for prognosis and management. CTD associated ILD (CTD-ILD) occurs most commonly in the context of an established CTD, but can be the first and/or only manifestation of an occult CTD or occur in patients who have features suggestive of an autoimmune process, but not meeting diagnostic criteria for a defined CTD-recently defined as "interstitial pneumonia with autoimmune features" (IPAF). The detection of specific autoantibodies serves a critical role in the diagnosis of CTD-ILD, but there remains a lack of data to guide clinical practice including which autoantibodies should be tested on initial assessment and when or in whom serial testing should be performed. The implications of detecting autoantibodies in patients with IPAF on disease behaviour and management remain unknown. The evaluation of CTD-ILD is challenging due to the heterogeneity of presentations and types of CTD and ILD that may be encountered, and thus it is imperative that immunologic tests are interpreted in conjunction with a detailed rheumatologic history and examination and multidisciplinary collaboration between respiratory physicians, rheumatologists, immunologists, radiologists and pathologists.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jcm6050051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5447942PMC
May 2017

Clinical use and interpretation of serum protein electrophoresis and adjunct assays.

Br J Hosp Med (Lond) 2017 Feb;78(2):C18-C20

Clinical Immunologist and Allergist, Royal Prince Alfred Hospital, New South Wales, Australia and Clinical Associate Professor, Sydney Medical School, University of Sydney, New South Wales, Australia.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.12968/hmed.2017.78.2.C18DOI Listing
February 2017

A call for uniformity in implementing the IPAF (interstitial pneumonia with autoimmune features) criteria.

Eur Respir J 2016 12;48(6):1811-1813

Dept of Respiratory and Sleep Medicine, Royal Prince Alfred Hospital, Sydney, Australia

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1183/13993003.01259-2016DOI Listing
December 2016

TEST performance of a myositis panel in a clinical immunology laboratory in New South Wales, Australia.

Int J Rheum Dis 2016 Oct 1;19(10):996-1001. Epub 2015 Dec 1.

Clinical Immunology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.

Background: There is increasing recognition of a clinico-serological correlation between the idiopathic inflammatory myopathies and myositis-specific autoantibodies (MSA). We review the use of a line immunoassay-based myositis panel incorporating both MSA and myositis-associated autoantibodies (MAA) in a selected population of patients.

Methods: A retrospective analysis of patients with myositis panel assays performed in 2013 were reviewed and compared against clinical diagnoses.

Results: A total of 96 patient samples were evaluated, the clinical indications include 60 patients with suspected idiopathic inflammatory myositis (IIM), 24 patients with suspected interstitial lung disease (ILD) and 12 patients with suspected systemic autoimmune disease (SAD). In the myositis group, there were 21 patients diagnosed with IIM and 18 patients diagnosed with IIM had a positive myositis panel. Of the 39 patients without IIM, nine of these patients had a positive myositis panel. In the ILD group, 10 of 24 patients had a positive myositis panel; of these, two were diagnosed anti-synthetase syndrome (ASS) and five patients with ILD. In the suspected SAD group, three had positive myositis panel and all did not appear associated with their final diagnoses. In patients with a clinical diagnosis of IIM or ILD-associated SAD, four patients with anti-PL-12 were detected, three patients with anti-signal recognition protein, two patients with anti-Jo-1, and two patients with anti-Mi2.

Conclusions: The myositis panel is an objective investigative modality with a sensitivity of 80.00% and a specificity of 75.76% in a setting of high pretest clinical suspicion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1756-185X.12792DOI Listing
October 2016

IL-27 Directly Enhances Germinal Center B Cell Activity and Potentiates Lupus in Sanroque Mice.

J Immunol 2016 10 12;197(8):3008-3017. Epub 2016 Sep 12.

Immunology Division, Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia;

Germinal centers (GC) give rise to high-affinity and long-lived Abs and are critical in immunity and autoimmunity. IL-27 supports GCs by promoting survival and function of T follicular helper cells. We demonstrate that IL-27 also directly enhances GC B cell function. Exposure of naive human B cells to rIL-27 during in vitro activation enhanced their differentiation into CD20CD38CD27CD95CD10 cells, consistent with the surface marker phenotype of GC B cells. This effect was inhibited by loss-of-function mutations in STAT1 but not STAT3 To extend these findings, we studied the in vivo effects of IL-27 signals to B cells in the GC-driven Roquin lupus mouse model. Il27raRoquin mice exhibited significantly reduced GCs, IgG2a(c) autoantibodies, and nephritis. Mixed bone marrow chimeras confirmed that IL-27 acts through B cell- and CD4 T cell-intrinsic mechanisms to support GCs and alter the production of pathogenic Ig isotypes. To our knowledge, our data provide the first evidence that IL-27 signals directly to B cells promote GCs and support the role of IL-27 in lupus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4049/jimmunol.1600652DOI Listing
October 2016

The concordance of serial ANA tests in an Australian tertiary hospital pathology laboratory.

Pathology 2016 Oct 3;48(6):597-601. Epub 2016 Sep 3.

Royal Prince Alfred Hospital, Sydney, NSW, Australia; Sydney Medical School, University of Sydney, NSW, Australia.

The antinuclear antibody (ANA) tests are some of the more frequently requested tests for the diagnosis of autoimmunity. Although they are used primarily as diagnostic blood tests, multiple requests on the same patient continue to be encountered in the laboratory. This retrospective analysis of serial ANA testing at one pathology laboratory in Australia is the first study that examines the statistical concordance and possible implications of this on clinical practice. High-titred ANA have quite good repeatability for titre and pattern, and low-titred ANA, which can be non-specific, have poor repeatability. Staining patterns are, in general, almost random in nature on serial tests when compared to the first-obtained ANA pattern for each patient. This study confirms that there is little benefit in serial ANA testing, and only if there is a clear change in the patient's clinical picture would repeat of an initial low-titred ANA be useful. The findings reinforce the need for pathology stewardship to minimise costs, wasted resources and unnecessary referrals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.pathol.2016.06.003DOI Listing
October 2016

Unique and shared signaling pathways cooperate to regulate the differentiation of human CD4+ T cells into distinct effector subsets.

J Exp Med 2016 07 11;213(8):1589-608. Epub 2016 Jul 11.

Immunology Division, Garvan Institute of Medical Research, Darlinghurst 2010, Australia St Vincent's Clinical School, Darlinghurst 2010, Australia.

Naive CD4(+) T cells differentiate into specific effector subsets-Th1, Th2, Th17, and T follicular helper (Tfh)-that provide immunity against pathogen infection. The signaling pathways involved in generating these effector cells are partially known. However, the effects of mutations underlying human primary immunodeficiencies on these processes, and how they compromise specific immune responses, remain unresolved. By studying individuals with mutations in key signaling pathways, we identified nonredundant pathways regulating human CD4(+) T cell differentiation in vitro. IL12Rβ1/TYK2 and IFN-γR/STAT1 function in a feed-forward loop to induce Th1 cells, whereas IL-21/IL-21R/STAT3 signaling is required for Th17, Tfh, and IL-10-secreting cells. IL12Rβ1/TYK2 and NEMO are also required for Th17 induction. Strikingly, gain-of-function STAT1 mutations recapitulated the impact of dominant-negative STAT3 mutations on Tfh and Th17 cells, revealing a putative inhibitory effect of hypermorphic STAT1 over STAT3. These findings provide mechanistic insight into the requirements for human T cell effector function, and explain clinical manifestations of these immunodeficient conditions. Furthermore, they identify molecules that could be targeted to modulate CD4(+) T cell effector function in the settings of infection, vaccination, or immune dysregulation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1084/jem.20151467DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4986526PMC
July 2016

Monogenic mutations differentially affect the quantity and quality of T follicular helper cells in patients with human primary immunodeficiencies.

J Allergy Clin Immunol 2015 Oct 7;136(4):993-1006.e1. Epub 2015 Jul 7.

Immunology Research Program, Garvan Institute of Medical Research, Darlinghurst, Australia; St Vincent's Clinical School, UNSW Australia, Melbourne, Australia. Electronic address:

Background: Follicular helper T (TFH) cells underpin T cell-dependent humoral immunity and the success of most vaccines. TFH cells also contribute to human immune disorders, such as autoimmunity, immunodeficiency, and malignancy. Understanding the molecular requirements for the generation and function of TFH cells will provide strategies for targeting these cells to modulate their behavior in the setting of these immunologic abnormalities.

Objective: We sought to determine the signaling pathways and cellular interactions required for the development and function of TFH cells in human subjects.

Methods: Human primary immunodeficiencies (PIDs) resulting from monogenic mutations provide a unique opportunity to assess the requirement for particular molecules in regulating human lymphocyte function. Circulating follicular helper T (cTFH) cell subsets, memory B cells, and serum immunoglobulin levels were quantified and functionally assessed in healthy control subjects, as well as in patients with PIDs resulting from mutations in STAT3, STAT1, TYK2, IL21, IL21R, IL10R, IFNGR1/2, IL12RB1, CD40LG, NEMO, ICOS, or BTK.

Results: Loss-of-function (LOF) mutations in STAT3, IL10R, CD40LG, NEMO, ICOS, or BTK reduced cTFH cell frequencies. STAT3 and IL21/R LOF and STAT1 gain-of-function mutations skewed cTFH cell differentiation toward a phenotype characterized by overexpression of IFN-γ and programmed death 1. IFN-γ inhibited cTFH cell function in vitro and in vivo, as corroborated by hypergammaglobulinemia in patients with IFNGR1/2, STAT1, and IL12RB1 LOF mutations.

Conclusion: Specific mutations affect the quantity and quality of cTFH cells, highlighting the need to assess TFH cells in patients by using multiple criteria, including phenotype and function. Furthermore, IFN-γ functions in vivo to restrain TFH cell-induced B-cell differentiation. These findings shed new light on TFH cell biology and the integrated signaling pathways required for their generation, maintenance, and effector function and explain the compromised humoral immunity seen in patients with some PIDs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2015.05.036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5042203PMC
October 2015

STAT3 is a critical cell-intrinsic regulator of human unconventional T cell numbers and function.

J Exp Med 2015 Jun 4;212(6):855-64. Epub 2015 May 4.

Immunology Division, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia St. Vincent's Clinical School and School of Women's and Children's Health, University of New South Wales, Sydney, NSW 2052, Australia

Unconventional T cells such as γδ T cells, natural killer T cells (NKT cells) and mucosal-associated invariant T cells (MAIT cells) are a major component of the immune system; however, the cytokine signaling pathways that control their development and function in humans are unknown. Primary immunodeficiencies caused by single gene mutations provide a unique opportunity to investigate the role of specific molecules in regulating human lymphocyte development and function. We found that individuals with loss-of-function mutations in STAT3 had reduced numbers of peripheral blood MAIT and NKT but not γδ T cells. Analysis of STAT3 mosaic individuals revealed that this effect was cell intrinsic. Surprisingly, the residual STAT3-deficient MAIT cells expressed normal levels of the transcription factor RORγt. Despite this, they displayed a deficiency in secretion of IL-17A and IL-17F, but were able to secrete normal levels of cytokines such as IFNγ and TNF. The deficiency in MAIT and NKT cells in STAT3-deficient patients was mirrored by loss-of-function mutations in IL12RB1 and IL21R, respectively. Thus, these results reveal for the first time the essential role of STAT3 signaling downstream of IL-23R and IL-21R in controlling human MAIT and NKT cell numbers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1084/jem.20141992DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4451129PMC
June 2015

Poor positive predictive value of serum immunoglobulin G4 concentrations in the diagnosis of immunoglobulin G4-related sclerosing disease.

Asia Pac Allergy 2014 Jul 29;4(3):172-6. Epub 2014 Jul 29.

Department of Clinical Immunology, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia.

Background: Immunoglobulin G4 (IgG4)-related sclerosing disease is a recently described clinicopathological entity with diverse manifestations including, amongst others, autoimmune pancreatitis, sclerosing cholangitis, sclerosing sialadenitis and retroperitoneal fibrosis. Elevated serum IgG4 concentration has been described as the hallmark of this condition with reported good sensitivity and specificity.

Objective: We sought to establish the utility of serum IgG4 concentrations in the diagnosis of IgG4-related sclerosing disease by determining how many serum samples with elevated IgG4 from an unselected population would originate from patients who fulfilled criteria for this diagnosis.

Methods: The clinical features and laboratory characteristics of patients whose serum IgG4 concentration was greater than 1.30 g/L were analysed retrospectively from a total of 1,258 IgG subclass measurements performed in a tertiary hospital diagnostic laboratory.

Results: Eighty patients (6.4%) had elevated IgG4 concentrations greater than 1.30 g/L. Nine of 61 patients had the diagnosis of IgG4-related sclerosing disease, giving a poor positive predictive value of 15%. The median serum IgG4 concentrations of those with and without IgG4-related sclerosing disease were 2.16 g/L and 1.86 g/L, respectively (p = 0.22).

Conclusion: Serum IgG4 concentration has poor positive predictive value in the diagnosis of IgG4-related sclerosing disease and, therefore, the clinical significance of elevated serum IgG4 concentration alone must be interpreted with caution.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5415/apallergy.2014.4.3.172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4116044PMC
July 2014

Naive and memory human B cells have distinct requirements for STAT3 activation to differentiate into antibody-secreting plasma cells.

J Exp Med 2013 Nov 11;210(12):2739-53. Epub 2013 Nov 11.

Immunology and Immunodeficiency Group, Immunology Research Program, Garvan Institute of Medical Research, Darlinghurst, NSW 2010, Australia.

Long-lived antibody memory is mediated by the combined effects of long-lived plasma cells (PCs) and memory B cells generated in response to T cell-dependent antigens (Ags). IL-10 and IL-21 can activate multiple signaling pathways, including STAT1, STAT3, and STAT5; ERK; PI3K/Akt, and potently promote human B cell differentiation. We previously showed that loss-of-function mutations in STAT3, but not STAT1, abrogate IL-10- and IL-21-mediated differentiation of human naive B cells into plasmablasts. We report here that, in contrast to naive B cells, STAT3-deficient memory B cells responded to these STAT3-activating cytokines, differentiating into plasmablasts and secreting high levels of IgM, IgG, and IgA, as well as Ag-specific IgG. This was associated with the induction of the molecular machinery necessary for PC formation. Mutations in IL21R, however, abolished IL-21-induced responses of both naive and memory human B cells and compromised memory B cell formation in vivo. These findings reveal a key role for IL-21R/STAT3 signaling in regulating human B cell function. Furthermore, our results indicate that the threshold of STAT3 activation required for differentiation is lower in memory compared with naive B cells, thereby identifying an intrinsic difference in the mechanism underlying differentiation of naive versus memory B cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1084/jem.20130323DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3832925PMC
November 2013

IL-21 signalling via STAT3 primes human naive B cells to respond to IL-2 to enhance their differentiation into plasmablasts.

Blood 2013 Dec 24;122(24):3940-50. Epub 2013 Oct 24.

Immunology Research Program, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia;

B-cell responses are guided by the integration of signals through the B-cell receptor (BCR), CD40, and cytokine receptors. The common γ chain (γc)-binding cytokine interleukin (IL)-21 drives humoral immune responses via STAT3-dependent induction of transcription factors required for plasma cell generation. We investigated additional mechanisms by which IL-21/STAT3 signaling modulates human B-cell responses by studying patients with STAT3 mutations. IL-21 strongly induced CD25 (IL-2Rα) in normal, but not STAT3-deficient, CD40L-stimulated naïve B cells. Chromatin immunoprecipitation confirmed IL2RA as a direct target of STAT3. IL-21-induced CD25 expression was also impaired on B cells from patients with IL2RG or IL21R mutations, confirming a requirement for intact IL-21R signaling in this process. IL-2 increased plasmablast generation and immunoglobulin secretion from normal, but not CD25-deficient, naïve B cells stimulated with CD40L/IL-21. IL-2 and IL-21 were produced by T follicular helper cells, and neutralizing both cytokines abolished the B-cell helper capacity of these cells. Our results demonstrate that IL-21, via STAT3, sensitizes B cells to the stimulatory effects of IL-2. Thus, IL-2 may play an adjunctive role in IL-21-induced B-cell differentiation. Lack of this secondary effect of IL-21 may amplify the humoral immunodeficiency in patients with mutations in STAT3, IL2RG, or IL21R due to impaired responsiveness to IL-21.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/blood-2013-06-506865DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3854113PMC
December 2013

Signal transducer and activator of transcription 3 (STAT3) mutations underlying autosomal dominant hyper-IgE syndrome impair human CD8(+) T-cell memory formation and function.

J Allergy Clin Immunol 2013 Aug 4;132(2):400-11.e9. Epub 2013 Jul 4.

Immunology Research Program, Garvan Institute of Medical Research, Darlinghurst, Australia.

Background: The capacity of CD8(+) T cells to control infections and mediate antitumor immunity requires the development and survival of effector and memory cells. IL-21 has emerged as a potent inducer of CD8(+) T-cell effector function and memory development in mouse models of infectious disease. However, the role of IL-21 and associated signaling pathways in protective CD8(+) T-cell immunity in human subjects is unknown.

Objective: We sought to determine which signaling pathways mediate the effects of IL-21 on human CD8(+) T cells and whether defects in these pathways contribute to disease pathogenesis in patients with primary immunodeficiencies caused by mutations in components of the IL-21 signaling cascade.

Methods: Human primary immunodeficiencies resulting from monogenic mutations provide a unique opportunity to assess the requirement for particular molecules in regulating human lymphocyte function. Lymphocytes from patients with loss-of-function mutations in signal transducer and activator of transcription 1 (STAT1), STAT3, or IL-21 receptor (IL21R) were used to assess the respective roles of these genes in human CD8(+) T-cell differentiation in vivo and in vitro.

Results: Mutations in STAT3 and IL21R, but not STAT1, led to a decrease in multiple memory CD8(+) T-cell subsets in vivo, indicating that STAT3 signaling, possibly downstream of IL-21R, regulates the memory cell pool. Furthermore, STAT3 was important for inducing the lytic machinery in IL-21-stimulated naive CD8(+) T cells. However, this defect was overcome by T-cell receptor engagement.

Conclusion: The IL-21R/STAT3 pathway is required for many aspects of human CD8(+) T-cell behavior but in some cases can be compensated by other signals. This helps explain the relatively mild susceptibility to viral disease observed in STAT3- and IL-21R-deficient subjects.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2013.05.029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3785237PMC
August 2013

An antibody-based leukocyte-capture microarray for the diagnosis of systemic lupus erythematosus.

PLoS One 2013 13;8(3):e58199. Epub 2013 Mar 13.

Department of Clinical Immunology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.

The diagnosis of Systemic Lupus Erythematosus (SLE) is challenging due to its heterogeneous clinical presentation and the lack of robust biomarkers to distinguish it from other autoimmune diseases. Further, currently used laboratory tests do not readily distinguish active and inactive disease. Several groups have attempted to apply emerging high throughput profiling technologies to diagnose and monitor SLE. Despite showing promise, many are expensive and technically challenging for routine clinical use. The goal of this work is to develop a better diagnostic and monitoring tool for SLE. We report a highly customisable antibody microarray that consists of a duplicate arrangement of 82 antibodies directed against surface antigens on peripheral blood mononuclear cells (PMBCs). This high-throughput array was used to profile SLE patients (n = 60) with varying disease activity, compared to healthy controls (n = 24), patients with rheumatoid arthritis (n = 25), and other autoimmune diseases (n = 28). We used a computational algorithm to calculate a score from the entire microarray profile and correlated it with SLE disease activity. Our results demonstrate that leukocyte-capture microarray profiles can readily distinguish active SLE patients from healthy controls (AUROC = 0.84). When combined with the standard laboratory tests (serum anti-dsDNA, complements C3 and C4), the microarrays provide significantly increased discrimination. The antibody microarrays can be enhanced by the addition of other markers for potential application to the diagnosis and stratification of SLE, paving the way for the customised and accurate diagnosis and monitoring of SLE.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0058199PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3596412PMC
September 2013

Autoimmunity in primary antibody deficiency is associated with protein tyrosine phosphatase nonreceptor type 22 (PTPN22).

J Allergy Clin Immunol 2013 Apr 31;131(4):1130-5, 1135.e1. Epub 2012 Jul 31.

Department of Immunology and Translational Research, Canberra Hospital, and Department of Immunology, John Curtin School of Medical Research, Australian National University, Canberra, Australia.

Background: The 1858T allele of protein tyrosine phosphatase nonreceptor type 22 (PTPN22; R620W) exhibits one of the strongest and most consistent associations with sporadic autoimmune disease. Although autoimmunity is common in patients with primary antibody deficiency (PAD), it remains unknown whether its pathogenesis is similar when it arises in this context compared with in immunocompetent patients.

Objective: We set out to determine whether the 1858T allele of PTPN22 was associated with PAD or with autoimmunity in the context of PAD.

Methods: We genotyped rs2476601 (g.1858C>T), a single nucleotide polymorphism encoding substitution of arginine for tryptophan in PTPN22 (R620W), in 193 patients with PAD and 148 control subjects from an Australian cohort. We also performed a subgroup analysis according to the presence of autoimmunity and B-cell phenotypes.

Results: C/T and T/T PTPN22 genotypes were more common in patients with PAD than in the matched control subjects (C/T, 18.1% vs 9.5%; T/T, 1.04% vs 0.6%). The T allele was associated with an increased risk of PAD relative to control subjects (odds ratio, 2.10; 95% CI, 1.11-4.00). The distribution of genotypes in control subjects was similar to those reported previously and did not deviate significantly from Hardy-Weinberg equilibrium. We found a strong association between the 1858T allele and PAD with coexistent autoimmune diseases. In patients with PAD and autoimmunity, 16 (43.2%) of 37 had at least one T allele of PTPN22 compared with 27 (17.3%) of 156 with the C/C genotype (P=.0014; odds ratio, 3.64; 95% CI, 1.68-7.88). We found no evidence that this effect was mediated by enrichment of CD21low B cells.

Conclusion: The 1858T PTPN22 allele is strongly associated with autoimmunity in patients with PAD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2012.06.023DOI Listing
April 2013

Expansion of somatically reverted memory CD8+ T cells in patients with X-linked lymphoproliferative disease caused by selective pressure from Epstein-Barr virus.

J Exp Med 2012 May 9;209(5):913-24. Epub 2012 Apr 9.

Immunology Research Program, Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia.

Patients with the primary immunodeficiency X-linked lymphoproliferative disease (XLP), which is caused by mutations in SH2D1A, are highly susceptible to Epstein-Barr virus (EBV) infection. Nonetheless, some XLP patients demonstrate less severe clinical manifestations after primary infection. SH2D1A encodes the adaptor molecule SLAM-associated protein (SAP), which is expressed in T and natural killer cells and is required for cytotoxicity against B cells, the reservoir for EBV. It is not known why the clinical presentation of XLP is so variable. In this study, we report for the first time the occurrence of somatic reversion in XLP. Reverted SAP-expressing cells resided exclusively within the CD8(+) T cell subset, displayed a CD45RA(-)CCR7(-) effector memory phenotype, and were maintained at a stable level over time. Importantly, revertant CD8(+) SAP(+) T cells, but not SAP(-) cells, proliferated in response to EBV and killed EBV-infected B cells. As somatic reversion correlated with EBV infection, we propose that the virus exerts a selective pressure on the reverted cells, resulting in their expansion in vivo and host protection against ongoing infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1084/jem.20112391DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3348103PMC
May 2012

Clearing the complexity: immune complexes and their treatment in lupus nephritis.

Int J Nephrol Renovasc Dis 2011 11;4:17-28. Epub 2011 Jan 11.

Department of Clinical Immunology, Royal Prince Alfred Hospital, Missenden Rd, Camperdown, NSW, Australia;

Systemic lupus erythematosus (SLE) is a classic antibody-mediated systemic autoimmune disease characterised by the development of autoantibodies to ubiquitous self-antigens (such as antinuclear antibodies and antidouble-stranded DNA antibodies) and widespread deposition of immune complexes in affected tissues. Deposition of immune complexes in the kidney results in glomerular damage and occurs in all forms of lupus nephritis. The development of nephritis carries a poor prognosis and high risk of developing end-stage renal failure despite recent therapeutic advances. Here we review the role of DNA-anti-DNA immune complexes in the pathogenesis of lupus nephritis and possible new treatment strategies aimed at their control.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/IJNRD.S10233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3108794PMC
July 2011

Customising an antibody leukocyte capture microarray for systemic lupus erythematosus: beyond biomarker discovery.

Proteomics Clin Appl 2010 Feb 2;4(2):179-89. Epub 2009 Dec 2.

Muscle Research Unit, Bosch Institute, The University of Sydney, Sydney, NSW, Australia.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease that has heterogeneous clinical manifestation with diverse patterns of organ involvement, autoantibody profiles and varying degrees of severity of disease. Research and clinical experience indicate that different subtypes of SLE patients will likely benefit from more tailored treatment regimes, but we currently lack a fast and objective test with high enough sensitivity to enable us to perform such sub-grouping for clinical use. In this article, we review how proteomic technologies could be used as such an objective test. In particular, we extensively review many leukocyte surface markers that are known to have an association with the pathogenesis of SLE, and we discuss how these markers can be used in the further development of a novel SLE-specific antibody leukocyte capture microarray. In addition, we review some bioinformatics challenges and current methods for using the data generated by these cell-capture microarrays in clinical use. In a broader context, we hope our experience in developing a disease specific cell-capture microarray for clinical application can be a guide to other proteomic practitioners who intend to extend their technologies to develop clinical diagnostic and prognostic tests for complex diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/prca.200900165DOI Listing
February 2010

Use of cardiac MR imaging to evaluate the presence of myocarditis in autoimmune myositis: three cases.

Rheumatol Int 2012 Mar 5;32(3):779-82. Epub 2010 Jan 5.

Royal Prince Alfred Hospital, Camperdown, NSW, Australia.

Cardiac involvement in patients with idiopathic inflammatory myopathies (autoimmune myositis) is important to detect because it confers an increased risk of mortality. However, detection of myocardial involvement is hampered by a lack of sensitivity of traditional non-invasive methods, and the finding of elevated cardiac troponin T levels that may be due to regenerating skeletal muscle, rather than myocardial damage. Here, we describe three cases of inflammatory myositis with elevated troponin T levels, and non-specific echocardiographic and ECG findings. Cardiac MR imaging was useful in the evaluation for the presence of myocarditis or alternative cardiac pathology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00296-009-1324-6DOI Listing
March 2012

Antibodies to cyclic citrullinated peptide in patients with chronic arthritis attending an arthritis-monitoring clinic.

J Clin Rheumatol 2005 Jun;11(3):150-2

Central Sydney Immunology Laboratory, Royal Prince Alfred Hospital, Camperdown, Australia.

Background: Early diagnosis of rheumatoid arthritis allows prompt initiation of antirheumatic therapy, which is associated with improved outcome. The use of IgM rheumatoid factor, the most widely used serologic test in assisting the diagnosis of rheumatoid arthritis, is limited by low specificity. An enzyme-linked immunosorbent assay test detecting antibodies to cyclic citrullinated peptide (CCP) has been developed with apparently higher specificity for rheumatoid arthritis.

Aim: We aimed to evaluate an assay for anti-CCP antibodies by determining the prevalence and titer of antibodies to CCP in a group of patients with chronic arthritis.

Method: Thirty-four sera were collected from outpatients attending an arthritis-monitoring clinic and tested for anti-CCP and IgM rheumatoid factor.

Results: Anti-CCP and rheumatoid factor were detected in 86% and 72% of patients with rheumatoid arthritis, respectively. Six patients negative for rheumatoid factor were positive for anti-CCP.

Conclusion: Anti-CCP antibodies are frequently detectable in high titer in patients with longstanding rheumatoid arthritis. This assay may be especially helpful in such cases when positive in rheumatoid factor-negative patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/01.rhu.0000164818.98410.2fDOI Listing
June 2005

Impaired humoral immunity in X-linked lymphoproliferative disease is associated with defective IL-10 production by CD4+ T cells.

J Clin Invest 2005 Apr 3;115(4):1049-59. Epub 2005 Mar 3.

Centenary Institute of Cancer Medicine and Cell Biology, Newtown, New South Wales, Australia.

X-linked lymphoproliferative disease (XLP) is an often-fatal immunodeficiency characterized by hypogammaglobulinemia, fulminant infectious mononucleosis, and/or lymphoma. The genetic lesion in XLP, SH2D1A, encodes the adaptor protein SAP (signaling lymphocytic activation molecule-associated [SLAM-associated] protein); however, the mechanism(s) by which mutations in SH2D1A causes hypogammaglobulinemia is unknown. Our analysis of 14 XLP patients revealed normal B cell development but a marked reduction in the number of memory B cells. The few memory cells detected were IgM(+), revealing deficient isotype switching in vivo. However, XLP B cells underwent proliferation and differentiation in vitro as efficiently as control B cells, which indicates that the block in differentiation in vivo is B cell extrinsic. This possibility is supported by the finding that XLP CD4(+) T cells did not efficiently differentiate into IL-10(+) effector cells or provide optimal B cell help in vitro. Importantly, the B cell help provided by SAP-deficient CD4(+) T cells was improved by provision of exogenous IL-10 or ectopic expression of SAP, which resulted in increased IL-10 production by T cells. XLP CD4(+) T cells also failed to efficiently upregulate expression of inducible costimulator (ICOS), a potent inducer of IL-10 production by CD4(+) T cells. Thus, insufficient IL-10 production may contribute to hypogammaglobulinemia in XLP. This finding suggests new strategies for treating this immunodeficiency.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1172/JCI23139DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1059448PMC
April 2005

Development of consensus guidelines for anticardiolipin and lupus anticoagulant testing.

Semin Thromb Hemost 2005 Feb;31(1):39-48

Division of Immunology, Queensland Health Pathology Services, Princess Alexandra and Royal Brisbane Hospitals, Brisbane, Queensland, Australia.

Interlaboratory and intermethod variation in commercial and in-house tests used for the measurement of anticardiolipin antibodies (aCL) and lupus anticoagulant (LA) limit the diagnostic value of the results from these tests. This short review summarizes published and unpublished guidelines (some developed using consensus procedures) on aCL and LA testing that are aimed at decreasing assay variation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1055/s-2005-863804DOI Listing
February 2005