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Dive into the research topics where Karen Herlyn is active.

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Featured researches published by Karen Herlyn.


Annals of the Rheumatic Diseases | 2005

B lymphocyte maturation in Wegener’s granulomatosis: a comparative analysis of VH genes from endonasal lesions

Jan Voswinkel; Antje Mueller; Jan A Kraemer; Peter Lamprecht; Karen Herlyn; Konstanze Holl-Ulrich; Alfred C. Feller; Silke Pitann; Angela Gause; Wolfgang L. Gross

Background: Anti-neutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) are highly specific for Wegener’s granulomatosis (WG). Evidence for a pivotal role of PR3-ANCA in the induction of vasculitis has been demonstrated. B cell clusters have been observed within endonasal biopsy specimens. Objectives: To determine whether B cell selection and maturation take place in granulomatous lesions of WG. Methods: Granulomatous lesions and the immunoglobulin (VH) gene repertoire from nasal tissue of six WG patients—two active and two smouldering localised WG (ANCA negative, restricted to respiratory tract), plus one active and one smouldering PR3-ANCA positive generalised WG—were characterised by immunohistochemistry, polymerase chain reaction, cloning, DNA sequencing and database comparison. Results: B lymphocyte-rich, follicle-like areas were observed proximal to PR3 positive cells and plasma cells in granulomatous lesions; 184 VH genes from these granulomatous lesions were compared with 84 VH genes from peripheral blood of a healthy donor. The mutational pattern of VH genes from active WG resembled memory B cells. Structural homologies of VH genes from granulomatous lesions to PR3-ANCA encoding genes were detected. Significantly more genes (55%, 45%, and 53%, respectively) from active WG compared with the healthy repertoire carried mutations to negatively charged amino acids within the binding site coding regions, favouring affinity to the positively charged PR3. Conclusions: Selection and affinity maturation of potentially PR3-ANCA producing autoreactive B cells may start in granulomatous lesions, thereby contributing to disease progression from ANCA negative localised to PR3-ANCA positive generalised WG.


Annals of the Rheumatic Diseases | 2012

Rituximab for refractory granulomatosis with polyangiitis (Wegener's granulomatosis): comparison of efficacy in granulomatous versus vasculitic manifestations

Julia U. Holle; Christin Dubrau; Karen Herlyn; Martin Heller; Petra Ambrosch; Bernhard Noelle; Eva Reinhold-Keller; Wolfgang L. Gross

Objective First, to investigate the overall efficacy and safety of rituximab (RTX) in refractory granulomatosis with polyangiitis (GPA) in a tertiary referral centre. Second, to compare the efficacy of RTX in granulomatous and vasculitic manifestations in GPA. Patients and methods This study comprised a retrospective, standardised data collection from all patients who received RTX for refractory Wegeners granulomatosis from 2002 to 2010. Patients were assessed by a standardised interdisciplinary diagnostic procedure (including ear, nose and throat and ophthalmology assessment, MRI, immunodiagnostics, B-cell levels and Birmingham Vasculitis Activity Score) and were treated by standardised therapeutic regimens according to available evidence. Results 59 patients received 75 cycles of RTX. 9.3% achieved complete remission. A response was documented in 61.3% (improvement in 52%, unchanged disease activity in 9.3%), 26.7% had refractory disease. Birmingham Vasculitis Activity Score, disease extent index, erythrocyte sedimentation rate, C-reactive protein and prednisolone demand decreased significantly. All patients achieved B-cell depletion. Granulomatous manifestations such as orbital granuloma and pachymeningitis were more frequently refractory to RTX than vasculitis or other granulomatous manifestations. Thus, for example, complete remission/improvement was found in 89.2% of patients with renal disease and in only 44.4% of those with orbital masses (p=0.003). The relapse rate was 44.4% after a median period of 13.5 months. Adverse events occurred in 29%, pneumonia in 15% and death in 3%. Conclusion The overall response rate of refractory GPA to RTX was high (61.3% complete remission or improvement). Response rates of vasculitic manifestations were excellent; failure of response/progress was mostly due to granulomatous manifestations, especially orbital masses. Relapse rates were high (40%) despite maintenance treatment.


The Journal of Rheumatology | 2011

Development of Outcome Measures for Large-vessel Vasculitis for Use in Clinical Trials: Opportunities, Challenges, and Research Agenda

Sibel Zehra Aydin; Tanaz A. Kermani; Eric L. Matteson; Maarten Boers; Karen Herlyn; Raashid Luqmani; Tuhina Neogi; Philip Seo; Ravi Suppiah; Gunnar Tomasson; Peter A. Merkel

Giant cell (GCA) and Takayasu’s arteritis (TAK) are 2 forms of large-vessel vasculitis (LVV) that involve the aorta and its major branches. GCA has a predilection for the cranial branches, while TAK tends to affect the extracranial branches. Both disorders may also cause nonspecific constitutional symptoms. Although some clinical features are more common in one or the other disorder and the ages of initial presentation differ substantially, there is enough clinical and histopathologic overlap between these disorders that some investigators suggest GCA and TAK may be 2 processes within the spectrum of a single disease. There have been few randomized therapeutic trials completed in GCA, and none in TAK. The lack of therapeutic trials in LVV is only partially explained by the rarity of these diseases. It is likely that the lack of well validated outcome measures for LVV and uncertainties regarding trial design contribute to the paucity of trials for these diseases. An initiative to develop a core set of outcome measures for use in clinical trials of LVV was launched by the international OMERACT Vasculitis Working Group in 2009 and subsequently endorsed by the OMERACT community at the OMERACT 10 meeting. Aims of this initiative include: (1) to review the literature and existing data related to outcome assessments in LVV; (2) to obtain the opinion of experts and patients on disease content; and (3) to formulate a research agenda to facilitate a more data-based approach to outcomes development.


The Journal of Rheumatology | 2011

The OMERACT Core Set of Outcome Measures for Use in Clinical Trials of ANCA-associated Vasculitis

Peter A. Merkel; Sibel Zehra Aydin; Maarten Boers; Karen Herlyn; Philip Seo; Ravi Suppiah; Gunnar Tomasson; Raashid Luqmani

There has been a marked increase in the past 15 years in the number and quality of clinical trials in the idiopathic inflammatory vasculitides, especially the small-vessel vasculitides known as antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis [AAV; granulomatosis, with polyangiitis (Wegener’s)]. These trials have been conducted by multicenter, international groups in Europe and the United States with financial support provided by government agencies and biopharmaceutical companies. This increased clinical trial activity in vasculitis has been accompanied by the development and validation of new outcome measures — a challenging process for these complex, multiorgan system diseases. The international OMERACT Vasculitis Working Group has developed and implemented an iterative research agenda that has utilized accumulated experience and datasets from several multicenter clinical trials and large cohort studies. This work has led to the development, evaluation, validation, and endorsement, through the OMERACT consensus and validation processes, of a “core set” of outcome measurements for use in clinical trials of AAV. The core set includes domains of disease activity, damage assessment, patient-reported outcomes, and mortality; there is at least one validated outcome measurement instrument available for each domain. This report reviews the domains of illness in AAV included in the OMERACT core set, describes the instruments validated to measure these domains, and presents the approved core set.


Arthritis Care and Research | 2011

Health-related quality of life in patients with newly diagnosed antineutrophil cytoplasmic antibody-associated vasculitis.

Michael Walsh; Chetan Mukhtyar; Alfred Mahr; Karen Herlyn; Raashid Luqmani; Peter A. Merkel; David Jayne

Antineutrophil cytoplasmic antibody–associated vasculitis (AAV) can present with a broad spectrum of signs and symptoms. The relative effects of different manifestations on health‐related quality of life (HRQOL) are unknown.


Annals of the Rheumatic Diseases | 2001

Immunological and clinical follow up of hepatitis C virus associated cryoglobulinaemic vasculitis

Peter Lamprecht; Frank Moosig; Angela Gause; Karen Herlyn; Elena Csernok; H Hansen; Wolfgang L. Gross

OBJECTIVE To study immunological markers and compare these markers with standard measures for the clinical and immunological follow up of vasculitis activity in hepatitis C virus (HCV) associated cryoglobulinaemic vasculitis (CV). METHODS Serial serum samples from eight patients with newly diagnosed HCV associated CV were followed during interferon α treatment induced remission of the CV. Vasculitis activity and disease extent were evaluated with the Birmingham vasculitis activity score (BVAS) and disease extent index (DEI). Cryoglobulinaemia, complement levels (C3c, C4, and CH50), rheumatoid factor (RF), autoantibodies such as antinuclear antibodies, soluble interleukin 2 receptor (sIL2r), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble CD30 (sCD30) were determined. RESULTS All patients achieved either complete or partial remission of their CV during interferon α treatment. There was a significant reduction in vasculitis activity and disease extent (BVAS, DEI), cryoglobulinaemia, RF, sIL2r, sICAM-1, and sCD30. Complement C3c levels increased significantly during this period. Erythrocyte sedimentation rate and levels of complement C4 and CH50 did not change significantly. Both clinical measures (BVAS and DEI) correlated significantly only with C3c and sCD30. CONCLUSIONS Although this study was of only a small group of patients, it shows that BVAS and DEI as clinical measures and C3c and sCD30 as immunological markers may be useful in the follow up of disease activity of HCV associated CV. The data indicate that activity of the humoral (cryoglobulinaemia, RF, autoantibodies) and cellular (sIL2r, sICAM-1, sCD30) immune response and endothelial damage (sICAM-1) are found in HCV associated CV.


Rheumatology | 2014

Doubled prevalence rates of ANCA-associated vasculitides and giant cell arteritis between 1994 and 2006 in northern Germany

Karen Herlyn; Frederike Buckert; Wolfgang L. Gross; Eva Reinhold-Keller

OBJECTIVES The aim of this study was to investigate the period prevalences of ANCA-associated vasculitides (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic GPA (EGPA)/Churg-Strauss and GCA, in an urban and rural population in northern Germany in 2006 and to compare the data with our previous study performed in 1994. METHODS We identified of all patients with AAV or GCA via questionnaires to all hospital departments, physicians, health insurance providers, pension funds, reference laboratories for autoimmune diseases and death registries in Luebeck (city) and the rural region of Segeberg (population 468 962) between January and December 2006. The type of vasculitis, gender, year of birth, postal code and death were documented and re-evaluated. RESULTS One-hundred and fifty patients were identified, indicating a prevalence of 320 per million inhabitants for the complete catchment area (95% CI 285, 355). GCA was more prevalent than AAV: 171 (146, 197) vs 149 (126, 174). GCA and AAV have almost doubled since 1994. GCA increased from 240 (164, 315) to 440 (399, 481) per million in the population ≥ 50 years of age and AAV increased from 74 to 149 cases per million. GCA and AAV were more prevalent in the urban compared with the rural region. CONCLUSION The prevalence rates of AAV and GCA almost doubled from 1994 to 2006 for this region with a stable population and using an identical study design. Increased awareness has led to an earlier diagnosis of systemic vasculitis and improved activity-adapted treatment mostly based on randomized controlled trials has led to longer survival. Aspects such as environmental factors and exposure to certain substances need further research.


The Journal of Rheumatology | 2009

Progress towards a core set of outcome measures in small-vessel vasculitis. Report from OMERACT 9.

Peter A. Merkel; Karen Herlyn; Alfred Mahr; Tuhina Neogi; Philip Seo; Michael Walsh; Maarten Boers; Raashid Luqmani

The past decade has seen a substantial increase in the number and quality of clinical trials of new therapies for vasculitis, including randomized, controlled, multicenter trials that have successfully incorporated measures of disease activity and toxicity. However, because current treatment regimens for severe disease effectively induce initial remission and reduce mortality, future trials will focus on any of several goals including: (a) treatment of mild—moderate disease; (b) prevention of chronic damage; (c) reduction in treatment toxicity; or (d) more subtle differences in remission induction or maintenance. Thus, new trials will require outcome measure instruments that are more precise and are better able to detect effective treatments for different disease states and measure chronic manifestations of disease. The OMERACT Vasculitis Working Group comprises international clinical investigators with expertise in vasculitis who, since 2002, have worked collaboratively to advance the refinement of outcome measures in vasculitis, create new measures to address domains of illness not covered by current research approaches, and harmonize outcome assessment in vasculitis. The focus of the OMERACT group to date has been on outcome measures in small-vessel vasculitis with an overall goal of creating a core set of outcome measures for vasculitis, each of which fulfills the OMERACT filter of truth, discrimination, feasibility, and identifying additional domains requiring further research. This process has been informed by several ongoing projects providing data on outcomes of disease activity, disease-related damage, multidimensional health-related quality of life, and patient-reported ratings of the burden of vasculitis.


Rheumatology | 2013

Toll-like receptor TLR2 and TLR9 ligation triggers neutrophil activation in granulomatosis with polyangiitis

Julia U. Holle; Mirca Windmöller; Christina Lange; Wolfgang L. Gross; Karen Herlyn; Elena Csernok

OBJECTIVE The aim of the study was to characterize the expression of TLR2, TLR4 and TLR9 in PMNs of patients with granulomatosis with polyangiitis (GPA) and to elucidate the role of these receptors in GPA with respect to neutrophil activation. METHODS The expression of TLR2, TLR4 and TLR9 was determined on ex vivo PMNs in whole blood samples of GPA patients (n = 35) and healthy controls (HCs) (n = 24). Isolated PMNs were stimulated in vitro with TLR agonists and assessed for degranulation, membrane proteinase 3 (mPR3) expression, soluble l-selectin shedding and cytokine production (IL-8) in five GPA patients and five HCs. The priming effects of TLR2 and TLR9 ligation were assessed by measurement of serine protease activity after stimulation with PR3-ANCA. RESULTS There were no significant differences in the ex vivo expression of TLRs on PMNs in HCs and GPA patients. Stimulation of TLR4 and TLR9 induced MPO release, stimulation with TLR2, TLR4 and TLR9 ligands elicited IL-8 production and stimulation of TLR2 and TLR9 led to an upregulation in mPR3 expression on PMNs with no significant differences between GPA and HC after 1 or 24 h stimulation. Priming of PMNs with TLR2 and TLR9 ligands induced degranulation after subsequent stimulation with PR3-ANCA, which was comparable to priming with TNF-α. CONCLUSION Expression of TLR2, TLR4 and TLR9 in PMNs and the TLR-induced activation of PMNs was comparable in GPA and HC. mPR3 upregulation by TLR2 and TLR9 stimulation and the priming effect of TLR ligands on PMNs may have a potential implication for triggering disease activity during infection in GPA.


Journal of Cystic Fibrosis | 2015

Trends in bone mineral density in young adults with cystic fibrosis over a 15 year period.

Melissa S. Putman; Joshua F. Baker; Ahmet Uluer; Karen Herlyn; Allen Lapey; Leonard Sicilian; Angela Pizzo Tillotson; Catherine M. Gordon; Peter A. Merkel; Joel S. Finkelstein

BACKGROUND Improvements in clinical care have led to increased life expectancy in patients with cystic fibrosis (CF) over the past several decades. Whether these improvements have had significant effects on bone health in patients with CF is unclear. METHODS This is a cross-sectional study comparing clinical characteristics and bone mineral density (BMD) measured by dual energy X-ray absorptiometry (DXA) in adults with CF evaluated in 1995-1999 to age-, race-, and gender-matched patients with CF evaluated in 2011-2013 at the same center on calibrated DXA machines. RESULTS The cohorts were similar in terms of age, BMI, pancreatic insufficiency, presence of F508del mutation, and reproductive history. In the most recent cohort, pulmonary function was superior, and fewer patients had vitamin D deficiency or secondary hyperparathyroidism. Areal BMD measures of the PA spine, lateral spine, and distal radius were similarly low in the two cohorts. CONCLUSIONS Although pulmonary function and vitamin D status were better in patients in the present-day cohort, areal BMD of the spine was reduced in a significant number of patients and was no different in patients with CF today than in the late 1990s. Further attention to optimizing bone health may be necessary to prevent CF-related bone disease.

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Peter A. Merkel

University of Pennsylvania

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Philip Seo

Johns Hopkins University

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Frank Moosig

University of Birmingham

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