bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence of a novel aggrecan‐degrading activity in cartilage: Studies of mice deficient in both ADAMTS‐4 and ADAMTS‐5
Authors: Rogerson Fraser M. , Stanton Heather , East Charlotte J. , Golub Suzanne B. , Tutolo Leonie , Farmer Pamela J. , Fosang Amanda J.
Published: May 2008

Objective

To characterize aggrecan catabolism and the overall phenotype in mice deficient in both ADAMTS‐4 and ADAMTS‐5 (TS‐4/TS‐5 Δ‐cat) activity.

Methods

Femoral head cartilage from the joints of TS‐4/TS‐5 Δ‐cat mice and wild‐type mice were cultured in vitro, and aggrecan catabolism was stimulated with either interleukin‐1α (IL‐1α) or retinoic acid. Total aggrecan release was measured, and aggrecanase activity was examined by Western blotting using neoepitope antibodies for detecting cleavage at EGE373–374ALG, SELE1279–1280GRG, FREEE1467–1468GLG, and AQE1572–1573AGEG. Aggrecan catabolism in vivo was examined by Western blotting of cartilage that had been extracted immediately ex vivo.

Results

TS‐4/TS‐5 Δ‐cat mice were viable, fertile, and phenotypically normal. TS‐4/TS‐5 Δ‐cat cartilage explants did not release aggrecan in response to IL‐1α, and there was no detectable increase in aggrecanase neoepitopes. TS‐4/TS‐5 Δ‐cat cartilage explants released aggrecan in response to retinoic acid. There was no retinoic acid–stimulated cleavage at either EGE373–374ALG or AQE1572–1573AGEG. There was a low level of cleavage at SELE1279–1280GRG and major cleavage at FREEE1467–1468GLG. Ex vivo, cleavage at FREEE1467–1468GLG was substantially reduced, but still present, in TS‐4/TS‐5 Δ‐cat mouse cartilage compared with wild‐type mouse cartilage.

Conclusion

An aggrecanase other than ADAMTS‐4 and ADAMTS‐5 is expressed in mouse cartilage and is up‐regulated by retinoic acid but not IL‐1α. The novel aggrecanase appears to have different substrate specificity from either ADAMTS‐4 or ADAMTS‐5, cleaving E–G bonds but not E–A bonds. Neither ADAMTS‐4 nor ADAMTS‐5 is required for normal skeletal development or aggrecan turnover in cartilage.
Association between findings on delayed gadolinium‐enhanced magnetic resonance imaging of cartilage and future knee osteoarthritis
Authors: Owman Henrik , Tiderius Carl Johan , Neuman Paul , Nyquist Fredrik , Dahlberg Leif E.
Published: May 2008

Objective

To examine the predictive value of the delayed gadolinium‐enhanced magnetic resonance imaging of cartilage (dGEMRIC) index with regard to future radiographic osteoarthritis (OA).

Methods

In 1998, 17 knees in 11 men and 4 women with knee pain, normal results of weight‐bearing radiography, and arthroscopic cartilage changes ranging from superficial fibrillation to fissuring and softening were examined using dGEMRIC. Six years later, 16 of the 17 knees were reassessed for radiographic OA changes.

Results

At followup, 9 of the 16 knees showed radiographic OA changes. Two of them had undergone a knee joint replacement due to OA. In the knees with radiographic OA, the dGEMRIC index at baseline was lower than that in the knees without radiographic OA (P = 0.03).

Conclusion

The results of the present study support the dGEMRIC index as a clinically relevant measure of cartilage integrity and suggest that a low index may be predictive of the development of knee OA.
Suppressor activity among CD4+,CD25++ T cells is discriminated by membrane‐bound tumor necrosis factor α
Authors: Wang Jun , van Dongen Henrike , Scherer Hans Ulrich , Huizinga Tom W. J. , Toes Rene E. M.
Published: May 2008

Objective

Previous studies have shown that the suppressive capacity of CD4+,CD25++ T cells is compromised in patients with rheumatoid arthritis (RA) and restored by anti–tumor necrosis factor α (anti‐TNFα) therapy. Given the lack of specific cell surface markers for human Treg cells, this study aimed to define surface markers for identifying and enriching Treg cells with enhanced regulatory ability within the CD4+,CD25++ T cell compartment and to provide additional understanding of the effects of anti‐TNFα antibodies in humans.

Methods

The expression of membrane‐bound TNFα in human peripheral blood CD4+ T cells was analyzed by flow cytometry in healthy individuals and RA patients before and after anti‐TNFα treatment. Membrane‐bound TNFα‐positive and TNFα‐negative CD4+,CD25++ T cells were purified by fluorescence‐activated cell sorting, and their suppressive capacity was assessed in vitro by a standard suppression assay.

Results

A substantial number of CD4+,CD25++ T cells expressed membrane‐bound TNFα. Membrane‐bound TNFα‐positive CD4+,CD25++ T cells displayed reduced antiinflammatory cytokine production and less potent suppressor capacity, since 4 times more cells were required to achieve 50% inhibition compared with their membrane‐bound TNFα‐negative counterparts. Treatment of RA patients with TNFα‐specific antibodies led to a reduction in the number of membrane‐bound TNFα‐positive CD4+,CD25++ T cells from peripheral blood.

Conclusion

Our data indicate that the absence of membrane‐bound TNFα on CD4+,CD25++ T cells can be used to characterize and enrich for Treg cells with maximal suppressor potency. Enrichment of membrane‐bound TNFα‐negative CD4+,CD25+ cells in the CD4+,CD25++ T cell compartment may contribute to restoring the compromised suppressive ability of CD4+,CD25++ T cell populations in RA patients after anti‐TNFα treatment.
Effects of long‐term strontium ranelate treatment on the risk of nonvertebral and vertebral fractures in postmenopausal osteoporosis: Results of a five‐year, randomized, placebo‐controlled trial
Authors: Reginster Jean‐Yves , Felsenberg Dieter , Boonen Steven , Diez‐Perez Adolfo , Rizzoli Rene , Brandi Maria‐Luisa , Spector Tim D. , Brixen Kim , Goemaere Stefan , Cormier Catherine , Balogh Adam , Delmas Pierre D. , Meunier Pierre J.
Published: May 2008

Objective

This study was undertaken to assess the effect of strontium ranelate on nonvertebral and vertebral fractures in postmenopausal women with osteoporosis in a 5‐year, double‐blind, placebo‐controlled trial.

Methods

A total of 5,091 postmenopausal women with osteoporosis were randomized to receive either strontium ranelate at 2 gm/day or placebo for 5 years. The main efficacy criterion was the incidence of nonvertebral fractures. In addition, incidence of hip fractures was assessed, by post hoc analysis, in the subset of 1,128 patients who were at high risk of fractures (age 74 years or older with lumbar spine and femoral neck bone mineral density T scores −2.4 or less). The incidence of new vertebral fractures was assessed, using the semiquantitative method described by Genant, in the 3,646 patients in whom spinal radiography (a nonmandatory procedure) was performed during the course of the study. Fracture data were analyzed using the Kaplan‐Meier survival method.

Results

Of the 5,091 patients, 2,714 (53%) completed the study up to 5 years. The risk of nonvertebral fracture was reduced by 15% in the strontium ranelate group compared with the placebo group (relative risk 0.85 [95% confidence interval 0.73–0.99]). The risk of hip fracture was decreased by 43% (relative risk 0.57 [95% confidence interval 0.33–0.97]), and the risk of vertebral fracture was decreased by 24% (relative risk 0.76 [95% CI 0.65–0.88]) in the strontium ranelate group. After 5 years, the safety profile of strontium ranelate remained unchanged compared with the 3‐year findings.

Conclusion

Our findings indicate that treatment of postmenopausal osteoporosis with strontium ranelate results in a sustained reduction in the incidence of osteoporotic nonvertebral fractures, including hip fractures, and vertebral fractures over 5 years.
Relationship of meniscal damage, meniscal extrusion, malalignment, and joint laxity to subsequent cartilage loss in osteoarthritic knees
Authors: Sharma Leena , Eckstein Felix , Song Jing , Guermazi Ali , Prasad Pottumarthi , Kapoor Dipali , Cahue September , Marshall Meredith , Hudelmaier Martin , Dunlop Dorothy
Published: May 2008

Objective

Progressive knee osteoarthritis (OA) is believed to result from local factors acting in a systemic environment. Previous studies have not examined these factors concomitantly or compared quantitative and qualitative cartilage loss outcomes. The aim of this study was to test whether meniscal damage, meniscal extrusion, malalignment, and laxity each predicted tibiofemoral cartilage loss after controlling for the other factors.

Methods

Laxity and alignment were measured at baseline in individuals with knee OA. Magnetic resonance imaging included spin‐echo coronal and sagittal imaging for meniscal scoring and axial and coronal spoiled gradient echo sequences with water excitation for cartilage quantification. Tibial and weight‐bearing femoral condylar subchondral bone area and cartilage surface were segmented. Cartilage volume, denuded bone area, and cartilage thickness were quantified in each plate, with progression defined as cartilage loss >2 times the coefficient of variation for each plate. Qualitative outcome was assessed as worsening of the cartilage score. Logistic regression analysis with generalized estimating equations yielded odds ratios for each factor, adjusting for age, sex, body mass index, and the other factors.

Results

We studied 251 knees in 153 persons. After full adjustment, medial meniscal damage predicted medial tibial cartilage volume loss and tibial and femoral denuded bone increase, while varus malalignment predicted medial tibial cartilage volume and thickness loss and tibial and femoral denuded bone increase. Lateral meniscal damage predicted every lateral outcome. Laxity and meniscal extrusion had inconsistent effects. After full adjustment, no factor except medial laxity predicted qualitative outcome.

Conclusion

Using quantitative cartilage loss assessment, local factors that independently predicted tibial and femoral loss included medial meniscal damage and varus malalignment (medially) and lateral meniscal damage (laterally). A measurement of quantitative outcome was more sensitive at revealing these relationships than a qualitative approach.
Cardiac involvement in systemic sclerosis assessed by tissue‐doppler echocardiography during routine care: A controlled study of 100 consecutive patients
Authors: Meune Christophe , Avouac Jérôme , Wahbi Karim , Cabanes Laure , Wipff Julien , Mouthon Luc , Guillevin Loïc , Kahan André , Allanore Yannick
Published: May 2008

Objective

To assess the prevalence of primary cardiac complications in a large population of patients with systemic sclerosis (SSc), using recently developed echocardiographic techniques.

Methods

We prospectively studied 100 consecutive patients (mean ± SD age 54 ± 14 years; 86 women) presenting with SSc without pulmonary arterial hypertension or clinical manifestations of heart failure. All patients underwent standard echocardiography, along with measurements of longitudinal velocities by tissue Doppler imaging (TDI) to assess left ventricular (LV) and right ventricular (RV) contractility and LV diastolic function. Results were compared with those in 26 age‐ and sex‐matched healthy controls.

Results

Patients with SSc had a wider mean left atrial diameter and impaired relaxation compared with the controls. A trend was observed toward a smaller LV ejection fraction (EF) in the patients (mean ± SD 64.9 ± 0.6%) than in the controls (67.2 ± 0.7%), as well as higher pulmonary artery pressure (mean ± SD 33.3 ± 0.6 mm Hg versus 30.8 ± 1.0 mm Hg). LVEF was <55% in 7 patients versus none of the controls. Peak systolic mitral annular velocity as measured by TDI was <7.5 cm/second in 14 patients versus none of the controls (P = 0.040). Mitral annulus early diastolic velocity was <10 cm/second in 30 patients versus 2 of the controls (P = 0.022). Fifteen patients and none of the controls had reduced peak systolic tricuspid annular velocity (P = 0.039). The TDI results correlated with each other, but not with lung abnormalities or other disease characteristics.

Conclusion

Depression of LV and RV systolic and LV diastolic function is common in patients with SSc and is due to primary myocardial involvement. Considering the major contributions of TDI, the addition of this simple technique to standard measurements may improve the detection of heart involvement in patients with SSc.
Function of CD4+,CD25+ Treg cells in MRL/lpr mice is compromised by intrinsic defects in antigen‐presenting cells and effector T cells
Authors: Parietti Véronique , Monneaux Fanny , Décossas Marion , Muller Sylviane
Published: May 2008

Objective

Naturally occurring CD4+,CD25+ Treg cells are central in the maintenance of peripheral tolerance. Impaired activity and/or a lower frequency of these cells is involved in the emergence of autoimmunity. We undertook this study to analyze relative proportions and functional alterations of Treg cells in MRL/lpr mice.

Methods

The frequency of CD4+,CD25+ T cells in the peripheral blood of healthy and autoimmune mice was compared by flow cytometry. The capacity of CD4+,CD25+ T cells to inhibit the proliferation and cytokine secretion of CD4+,CD25− T cells was assessed after polyclonal activation.

Results

MRL/lpr mice exhibited a normal percentage of CD4+,CD25high T cells, and forkhead box P3 messenger RNA and protein expression in Treg cells was not altered. However, MRL/lpr Treg cells displayed a reduced capacity to suppress proliferation and to inhibit interferon‐γ secretion by syngeneic effector CD4+,CD25− T cells, as compared with syngeneic cocultures of CBA/J T cells. Moreover, effector MRL/lpr CD4+,CD25− T cells were substantially less susceptible to suppression even when cultured with CBA/J or MRL/lpr Treg cells. Crossover experiments led us to conclude that in MRL/lpr mice, each partner engaged in T cell regulation displays altered functions. Molecules involved in suppressive mechanisms (CTLA‐4 and CD80/CD86) are underexpressed, and antigen‐presenting cells (APCs) produce raised levels of interleukin‐6, which is known to abrogate suppression.

Conclusion

Our results suggest that although the frequency and phenotype of Treg cells in MRL/lpr mice are similar to those in normal mice, Treg cells in MRL/lpr mice are not properly stimulated by APCs and are unable to suppress proinflammatory cytokine secretion from effector T cells.
Anti‐CD20 therapy in patients with rheumatoid arthritis: Predictors of response and B cell subset regeneration after repeated treatment
Authors: Roll Petra , Dörner Thomas , Tony Hans‐Peter
Published: May 2008

Objective

B cell depletion with the anti‐CD20 antibody rituximab has proven efficacy in patients with rheumatoid arthritis (RA). The effects on B cell homeostasis after repeated treatments and the relationship of certain B cell subsets to clinical response or relapse are currently not known.

Methods

In this open‐label study, 17 patients with RA refractory to standard therapy were treated with 1 cycle of rituximab. Of these 17 patients, 11 received a second cycle of rituximab therapy. Immunophenotyping was performed before therapy and during B cell recovery.

Results

Twelve of 17 patients showed a good European League Against Rheumatism response after receiving 1 cycle of rituximab therapy. At the time of B cell recovery, the IgD+,CD27+ memory B cell subset was significantly larger (P = 0.019) in the nonresponder group. Within the group of 12 responders, 6 patients, whose disease was characterized by a significantly higher proportion of overall CD27+ memory B cells before therapy, experienced an early relapse (weeks 24–40 posttreatment). Eleven patients were re‐treated, again resulting in a good clinical response. B cell reconstitution followed a similar pattern after each cycle. The early reconstitution phase was characterized by immature CD38++,IgD+,CD10+ B cells, whereas the number of naive B cells increased continuously thereafter. The number of memory B cells was still reduced at the time of the second depletion but recovered to levels similar to those following the first cycle of therapy.

Conclusion

Data derived from repeated B lymphocyte depletion with rituximab in patients with RA suggest that analysis of certain memory B cell subsets provides information on efficacy, response, and late as well as early relapse, consistent with the conclusion that targeting memory B cells is a key to its mechanism of action.
A diagnostic score for molecular analysis of hereditary autoinflammatory syndromes with periodic fever in children
Authors: Gattorno M. , Sormani M. P. , D'Osualdo A. , Pelagatti M. A. , Caroli F. , Federici S. , Cecconi M. , Solari N. , Meini A. , Zulian F. , Obici L. , Breda L. , Martino S. , Tommasini A. , Bossi G. , Govers A. , Touitou I. , Woo P. , Frenkel J. , Koné‐Paut I. , Baldi M. , Ceccherini I. , Martini A.
Published: May 2008

Objective

To identify a set of clinical parameters that can predict the probability of carrying mutations in one of the genes associated with hereditary autoinflammatory syndromes.

Methods

A total of 228 consecutive patients with a clinical history of periodic fever were screened for mutations in the MVK, TNFRSF1A, and MEFV genes, and detailed clinical information was collected. A diagnostic score was formulated based on univariate and multivariate analyses in genetically positive and negative patients (training set). The diagnostic score was validated in an independent set of 77 patients (validation set).

Results

Young age at onset (odds ratio [OR] 0.94, P = 0.003), positive family history of periodic fever (OR 4.1, P = 0.039), thoracic pain (OR 4.6, P = 0.05), abdominal pain (OR 33.1, P < 0.001), diarrhea (OR 3.3, P = 0.028), and oral aphthosis (OR 0.2, P = 0.007) were found to be independently correlated with a positive genetic test result. These variables were combined in a linear score whose ability to predict a positive result on genetic testing was validated in an independent data set. In this latter set, the diagnostic score revealed high sensitivity (82%) and specificity (72%) for discriminating patients who were genetically positive from those who were negative. In patients with a high probability of having a positive result on genetic testing, a regression tree analysis provided the most reasonable order in which the genes should be screened.

Conclusion

The proposed approach in patients with periodic fever will increase the probability of obtaining positive results on genetic testing, with good specificity and sensitivity. Our results further help to optimize the molecular analysis by suggesting the order in which the genes should be screened.
Synovial fluid mesenchymal stem cells in health and early osteoarthritis: Detection and functional evaluation at the single‐cell level
Authors: Jones Elena A. , Crawford Aileen , English Anne , Henshaw Karen , Mundy Jenifer , Corscadden Diane , Chapman Tony , Emery Paul , Hatton Paul , McGonagle Dennis
Published: May 2008

Objective

Arthritic synovial fluid (SF) contains mesenchymal stem cells (MSCs), which could simply reflect their shedding from diseased joint structures. This study used the bovine model to explore SF MSCs in health and enumerated them at the earliest stages of human osteoarthritis (OA) in radiographically normal joints.

Methods

Clonogenicity and multipotentiality of normal bovine SF MSCs were compared with donor‐matched bone marrow (BM) MSCs at the single‐cell level. The colony‐forming unit–fibroblastic assay was used for MSC enumeration. The XTT assay was employed to assess cell proliferation, and flow cytometry was used to investigate the marker phenotype of bovine and human SF MSCs.

Results

Single MSCs were present in normal bovine SF, and 96% of them were able to expand at least 1 million–fold. These cells were CD271–, multipotential, considerably more clonogenic, and less adipogenic than matched BM MSCs. In both pellet assays and on polyglycolic acid scaffolds, SF clones displayed consistent chondrogenic differentiation, while BM clones were variable. MSCs were present in arthroscopically normal human joints and were increased 7‐fold in early OA (P = 0.034). Their numbers correlated with numbers of free microscopic synovial tissue fragments (r = 0.826, P < 0.0001). OA SF had a growth‐promoting effect on synovial MSCs.

Conclusion

This study confirms the presence of MSCs in normal SF and shows their numerical increase in early human OA. SF MSCs are likely to originate from synovium. These findings provide a platform for the exploration of the potential role of SF MSCs in joint homeostasis and for investigation of their utility in novel joint regeneration strategies.
Enhanced osteoclastogenesis in patients with tophaceous gout: Urate crystals promote osteoclast development through interactions with stromal cells
Authors: Dalbeth Nicola , Smith Timothy , Nicolson Bridget , Clark Barnaby , Callon Karen , Naot Dorit , Haskard Dorian O. , McQueen Fiona M. , Reid Ian R. , Cornish Jillian
Published: May 2008

Objective

To analyze cellular mechanisms of bone erosion in gout.

Methods

Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) from patients with gout were analyzed for the presence of osteoclast precursors. Fixed tophus and bone samples were analyzed by immunohistochemistry. Mechanisms of osteoclastogenesis were studied by culturing murine preosteoclast RAW 264.7 cells, bone marrow stromal ST2 cells, and human synovial fibroblasts with monosodium urate monohydrate (MSU) crystals.

Results

PBMCs from patients with severe erosive gout had the preferential ability to form osteoclast‐like cells in culture with RANKL and monocyte colony‐stimulating factor (M‐CSF). The number of PBMC‐derived tartrate‐resistant acid phosphatase (TRAP)–positive multinucleated cells strongly correlated with the number of tophi (r = 0.6296, P = 0.630). Patients with severe erosive and tophaceous gout also had higher circulating concentrations of RANKL and M‐CSF. Furthermore, greater numbers of TRAP‐positive multinucleated cells were cultured from SFMCs derived from gouty knee effusions than from paired PBMCs (P = 0.004). Immunohistochemical analysis demonstrated numerous multinucleated cells expressing osteoclast markers within tophi and at the interface between soft tissue and bone. MSU crystals did not directly promote osteoclast formation from RAW 264.7 cells in vitro. However, MSU crystals inhibited osteoprotegerin gene and protein expression in ST2 cells and human synovial fibroblasts, without significantly altering RANKL gene expression. Conditioned medium from ST2 cells cultured with MSU crystals promoted osteoclast formation from RAW 264.7 cells in the presence of RANKL.

Conclusion

Chronic tophaceous and erosive gout is characterized by enhanced osteoclast development. These data provide a rationale for the study of osteoclast‐targeted therapies for the prevention of bone damage in chronic gout.
Dramatic regulation of heparanase activity and angiogenesis gene expression in synovium from patients with rheumatoid arthritis
Authors: Li Rachel W. , Freeman Craig , Yu Di , Hindmarsh Elizabeth J. , Tymms Kathleen E. , Parish Christopher R. , Smith Paul N.
Published: May 2008

Objective

Although heparanase is recognized as a proangiogenic factor, the involvement of heparanase in rheumatoid arthritis (RA) is unclear. In this study, we assessed heparanase activity in synovial fluid (SF) and synovial tissue (ST) from patients with RA or osteoarthritis (OA), and analyzed the expression of angiogenic pathway–focused genes in ST from RA and OA patients.

Methods

SF and ST were obtained from the knees of patients with either RA or OA and from asymptomatic donors with no documented history of degenerative or inflammatory joint diseases. Heparanase activity was determined by an enzymatic assay using a radiolabeled substrate, and the presence of heparanase in ST was demonstrated by Western blotting. The expression of angiogenesis genes, including heparanase, in ST was analyzed by real‐time quantitative polymerase chain reaction.

Results

Heparanase activity was dramatically higher (>100‐fold) in SF and ST from RA patients than in SF and ST from OA patients and asymptomatic donors. Active heparanase enzyme was detected and heparanase messenger RNA was up‐regulated in ST from RA patients. We also found that angiogenesis gene expression was significantly regulated in RA synovium, and was correlated with heparanase activity.

Conclusion

These findings are novel and contribute to our understanding of joint destruction in RA, suggesting that heparanase may be a reliable prognostic factor for RA progression and an attractive target for the treatment of RA.
Age at onset–dependent presentations of premature hip osteoarthritis, avascular necrosis of the femoral head, or Legg‐Calvé‐Perthes disease in a single family, consequent upon a p.Gly1170Ser mutation of COL2A1
Authors: Su Peiqiang , Li Ru , Liu Shangli , Zhou Yan , Wang Xinguang , Patil Nilesh , Mow Christopher S. , Mason Justin C. , Huang Dongsheng , Wang Yiming
Published: May 2008

Objective

To identify the genetic abnormality responsible for osteoarthritis (OA), avascular necrosis (AVN) of the femoral head, and Legg‐Calvé‐Perthes disease in a single family, and to determine factors responsible for the distinct phenotypes manifested by different family members.

Methods

Forty‐two members of a 5‐generation family were recruited and investigated. Diagnosis was made by independent orthopedic surgeons and radiologists. Histopathologic changes of the diseased tissue were examined. Linkage analysis was performed with markers spanning the COL2A1 locus. Haplotypes were constructed and mutation of the gene was detected. Structures of the wild‐type and mutant proteins were modeled.

Results

Sixteen affected members were identified (5 with isolated precocious hip OA, 6 with AVN of the femoral head, and 5 with Legg‐Calvé‐Perthes disease). A p.Gly1170Ser mutation of COL2A1 cosegregated with the 3 diseases and was absent in controls. Of note, age at onset in relation to the closure status of the femoral head epiphysis was associated with the diseases, with Legg‐Calvé‐Perthes disease presenting prior to closure (at ages 6–14 years), AVN of the femoral head presenting during closure (at ages 15–18 years), and precocious OA of the hip presenting after closure (at ages 21–34 years). Molecular modeling predicted that the serine‐to‐glycine substitution loosens the helical structure of the protein.

Conclusion

The p.Gly1170Ser mutation of COL2A1 in the family described is responsible for pathology confined to the hip joint, which presents as isolated precocious hip OA, AVN of the femoral head, or Legg‐Calvé‐Perthes disease. Age at onset in relation to closure of the femoral head epiphysis appears to be a critical factor in determining disease pattern.
Decreased lubricin concentrations and markers of joint inflammation in the synovial fluid of patients with anterior cruciate ligament injury
Authors: Elsaid K. A. , Fleming B. C. , Oksendahl H. L. , Machan J. T. , Fadale P. D. , Hulstyn M. J. , Shalvoy R. , Jay G. D.
Published: May 2008

Objective

To study the effect of anterior cruciate ligament (ACL) injury on lubricin concentrations in synovial fluid (SF) and its correlation with time postinjury, inflammatory cytokines, lubricin‐degrading enzymes, and SF proteoglycan content.

Methods

SF samples were obtained from both knees of 30 patients with unilateral ACL insufficiency, 32–364 days postinjury. Lubricin, inflammatory cytokines (interleukin‐1β [IL‐1β], tumor necrosis factor α [TNFα], and IL‐6), and catabolic enzymes (procathepsin B and neutrophil elastase) were measured in SF from injured and contralateral (uninjured) joints, by enzyme‐linked immunosorbent assay. Sulfated glycosaminoglycan (sGAG) levels in the SF were measured by Alcian blue binding assay.

Results

SF lubricin concentrations were significantly (P < 0.001) reduced at an early stage following ACL injury when compared with those in the contralateral joint. Within 12 months, the lubricin concentration in the injured knee (slope = 0.006, SE = 0.00010, P < 0.001) approached that in the contralateral knee, which did not change with time (slope = −0.0002, SE = 0.00050, P = 0.71). TNFα levels showed a significant negative relationship with log2 lubricin levels. IL‐1β, TNFα, IL‐6, procathepsin B, and neutrophil elastase concentrations in SF from injured knees were greater in samples from recently injured knees compared with those that were chronically injured. There were no detectable cytokines or enzymes in the SF of contralateral joints. Concentrations of sGAG were significantly (P = 0.0002) higher in the SF from injured knees compared with the contralateral joints.

Conclusion

The decrease in SF lubricin concentrations following ACL injury may place the joint at an increased risk of wear‐induced damage as a consequence of lack of boundary lubrication, potentially leading to secondary osteoarthritis. The decrease in SF lubricin was associated with an increase in levels of inflammatory cytokines.
Functionally relevant variations of the interleukin‐10 gene associated with antineutrophil cytoplasmic antibody–negative Churg‐Strauss syndrome, but not with Wegener's granulomatosis
Authors: Wieczorek S. , Hellmich B. , Arning L. , Moosig F. , Lamprecht P. , Gross W. L. , Epplen J. T.
Published: May 2008

Objective

Wegener's granulomatosis (WG) and Churg‐Strauss syndrome (CSS) belong to the heterogeneous group of antineutrophil cytoplasmic antibody (ANCA)–associated vasculitides. Current understanding of their pathogenesis and genetic background is limited. Expression levels of interleukin‐10 (IL‐10), a potent and pleiotropic cytokine, are largely determined by variations in the gene encoding the IL‐10 precursor. This study was undertaken to determine the impact of IL10 polymorphisms on the pathogenesis of both WG and CSS in large cohorts.

Methods

Three single‐nucleotide polymorphisms (SNPs) tagging the promoter haplotypes of the IL10 gene (IL10 −3575, IL10 −1082, and IL10 −592) were analyzed in 403 patients with WG and 103 patients with CSS as well as 507 matched control subjects from Germany. In addition, 3 informative SNPs in other parts of IL10 were genotyped.

Results

None of the markers or their haplotypes was associated with WG or any of its subgroups classified according to ANCA status, sex, or presence of further WG genetic risk factors. In contrast, the IL10 −3575/−1082/−592 TAC haplotype, part of the extended ancient haplotype IL10.2, was highly significantly associated with ANCA‐negative CSS (χ2 = 19.14, P = 0.000012, corrected P = 0.0003, odds ratio 2.16, 95% confidence interval 1.52–3.06).

Conclusion

These findings challenge those from previous studies of IL10 in WG and provide further evidence that CSS and WG have distinct genetic backgrounds. Because the IL10.2 haplotype has been correlated reproducibly with increased IL10 expression, the possible role of IL‐10 in the pathogenesis of ANCA‐negative CSS needs to be further elucidated.
Cytokines secreted in response to Toll‐like receptor ligand stimulation modulate differentiation of human Th17 cells
Authors: Kattah Michael G. , Wong Michael T. , Yocum Matthew D. , Utz Paul J.
Published: May 2008

Objective

Th17 cells (interleukin‐17 [IL‐17]–secreting T helper cells) have been implicated in the pathogenesis of rheumatoid arthritis and other autoimmune diseases, but the soluble factors that influence human Th17 differentiation have yet to be fully elucidated. This study was undertaken to investigate the hypothesis that the cytokines secreted by human peripheral blood mononuclear cells (PBMCs) in response to a subset of Toll‐like receptor (TLR) ligands would influence Th17 polarization.

Methods

Supernatants from human PBMCs treated with a panel of TLR agonists were tested for their ability to induce de novo IL‐17 production in naive T helper cells. Multiplex cytokine analysis was used to identify candidate cytokines for subsequent blocking and sufficiency experiments.

Results

Conditioned media from PBMCs stimulated with TLR‐4 or TLR‐8/7 agonists, but not from those stimulated with TLR‐2/1, ‐3, or ‐9 agonists, evoked robust secretion of IL‐17 by T helper cells, independent of coculture with antigen‐presenting cells. Multiplex analysis of 22 cytokines and chemokines identified a 6‐factor cytokine signature that significantly correlated with IL‐17–inducing activity. T cell activation in the presence of recombinant IL‐1β, IL‐6, and IL‐23 reconstituted robust IL‐17 production, and this was enhanced by transforming growth factor β (TGFβ). IL‐6 suppressed the expression of forkhead box P3 and reversed TGFβ‐mediated inhibition of T cell proliferation, but did not trigger IL‐17 secretion. IL‐17 production was completely abrogated by anti–IL‐1 or IL‐1 receptor antagonist and partially inhibited by anti–IL‐6, anti–IL‐2, or exogenous retinoic acid, but not by anti–tumor necrosis factor α. IL‐1β and IL‐6 independently induced IL‐21 secretion, but the presence of IL‐21 alone was not sufficient for IL‐17 production.

Conclusion

These results indicate that ligation of a subset of TLRs generates proinflammatory cytokines that combine to potentiate human Th17 differentiation.
Activated memory B cell subsets correlate with disease activity in systemic lupus erythematosus: Delineation by expression of CD27, IgD, and CD95
Authors: Jacobi Annett M. , Reiter Karin , Mackay Meggan , Aranow Cynthia , Hiepe Falk , Radbruch Andreas , Hansen Arne , Burmester Gerd‐R. , Diamond Betty , Lipsky Peter E. , Dörner Thomas
Published: May 2008

Objective

Analysis of peripheral B cell subsets in patients with systemic lupus erythematosus (SLE) has provided evidence of specific alterations, such as an expansion of CD27++ plasma cells/blasts and transitional B cells. However, memory B cells in lupus have not been thoroughly investigated, and only recently a CD27− memory B cell subset was identified in the peripheral blood of lupus patients. Focusing on CD27− B cells, this study aimed to identify abnormalities in peripheral B cell subsets in patients with SLE.

Methods

Three independent cohorts of lupus patients were used to characterize CD27− memory B cells, using multiparameter flow cytometry and single‐cell reverse transcription–polymerase chain reaction of heavy‐chain transcripts.

Results

We identified a homogeneous subset of CD27−,IgD−,CD95+ memory B cells with an activated phenotype that was increased in patients with disease flares and that correlated with disease activity and serologic abnormalities. In contrast, the entire subset of CD27−,IgD− B cells was found to be heterogeneous, did not correlate significantly with lupus activity, and was also increased in patients with bacterial infections.

Conclusion

We conclude that CD95 is a useful marker to identify CD27− memory B cells with an activated phenotype, which might serve as a biomarker for lupus activity and as a target of further investigations aiming to elucidate the pathogenic potential of these cells and the mechanisms involved in the generation as well as regulation of this CD27−,IgD−,CD95+ memory B cell subset.
Aromatase expression in osteoarthritic and osteoporotic bone
Authors: Hernández José L. , Garcés Carlos M. , Sumillera Manuel , Fernández‐Aldasoro Eugenio V. , García‐Ibarbia Carmen , Ortiz‐Gómez Jesús A. , Arozamena Jana , Alonso María A. , Riancho José A.
Published: May 2008

Objective

Estrogen deprivation is a central mechanism in the development of osteoporosis with aging. Results from recent studies also suggest the involvement of estrogens in the pathophysiology of osteoarthritis (OA). Aromatization of androgenic precursors in peripheral tissue is the main source of estrogens in postmenopausal women and in men. However, the importance of aromatase expression in bone is a subject of controversy. This study was undertaken to determine aromatase expression in bone samples from patients with hip fracture and patients with OA.

Methods

We studied 104 patients with hip fracture (n = 60) or primary hip OA (n = 44). Aromatase expression was determined in trabecular bone samples from the femoral neck and in osteoblast cultures grown by the primary explant technique (n = 62), using real‐time reverse transcriptase–polymerase chain reaction.

Results

Aromatase RNA was detected in bone samples at levels similar to those found in adipose tissue. Transcript levels were significantly lower in bone tissue samples obtained from patients with OA than in those obtained from patients with fracture (P = 0.00001). Likewise, primary cultures of osteoblast cells from OA patients revealed lower aromatase expression than those of cells from fracture patients (P = 0.012). Results were independent of age or sex differences.

Conclusion

Our findings indicate that the aromatase gene is expressed in bone tissue in high amounts, similar to those found in adipose tissue, but transcript levels are lower in tissue samples and osteoblast cultures from patients with OA than in those from patients with hip fracture. Since estrogens may help to prevent local cartilage degradation, it can be speculated that such a reduced expression of aromatase could facilitate the development of OA.
A multicenter, randomized, double‐blind, placebo‐controlled trial of oral type I collagen treatment in patients with diffuse cutaneous systemic sclerosis: I. Oral type I collagen does not improve skin in all patients, but may improve skin in late‐phase disease
Authors: Postlethwaite Arnold E. , Wong Weng Kee , Clements Philip , Chatterjee Soumya , Fessler Barri J. , Kang Andrew H. , Korn Joseph , Mayes Maureen , Merkel Peter A. , Molitor Jerry A. , Moreland Larry , Rothfield Naomi , Simms Robert W. , Smith Edwin A. , Spiera Robert , Steen Virginia , Warrington Kenneth , White Barbara , Wigley Frederick , Furst Daniel E.
Published: May 2008

Objective

To investigate the safety and efficacy of oral bovine type I collagen (CI) treatment in patients who have had diffuse cutaneous systemic sclerosis (dcSSc; scleroderma) for ≤10 years.

Methods

One hundred sixty‐eight patients with dcSSc were enrolled in a double‐blind, placebo‐controlled trial of oral CI (500 μg/day) or placebo administered over 12 months, with a followup visit at month 15. The primary outcome was the modified Rodnan skin thickness score (MRSS). Other clinical and immune system parameters were also assessed.

Results

Intent‐to‐treat and modified intent‐to‐treat analyses showed that for the total population of patients with dcSSc, there were no significant differences in the mean change in MRSS or other key clinical parameters between the CI and placebo treatment groups at 12 months or at 15 months. However, in a subanalysis of the available data at month 15, the CI‐treated group of patients with late‐phase dcSSc experienced a significant reduction in the MRSS compared with that in the placebo‐treated patients with late‐phase dcSSc (change in MRSS at month 15 −7.9 versus −2.9; P = 0.0063).

Conclusion

Although the results from this trial did not meet the primary outcome goals, the findings from exploratory analyses indicated that CI treatment may benefit patients with late‐phase dcSSc. This new treatment strategy and preliminary clinical observations in patients with dcSSc need to be corroborated.
The rheumatoid arthritis–associated allele HLA–DR10 (DRB1*1001) shares part of its repertoire with HLA–DR1 (DRB1*0101) and HLA–DR4 (DRB*0401)
Authors: Alvarez Iñaki , Collado Javier , Daura Xavier , Colomé Nuria , Rodríguez‐García Marta , Gallart Teresa , Canals Francesc , Jaraquemada Dolores
Published: May 2008

Objective

To identify the peptide anchor motif for the rheumatoid arthritis (RA)–related HLA allele, DR10, and find shared natural ligands or sequence similarities with the other disease‐associated alleles, DR1 and DR4.

Methods

The HLA–DR10–associated peptides were purified, and a proportion of these natural ligands were de novo sequenced by mass spectrometry. Based on crystallographic structures, the complexes formed by peptide influenza virus hemagglutinin HA306–318 with DR1, DR4, and DR10 were modeled, and binding scores were obtained.

Results

A total of 238 peptides were sequenced, and the anchor motif of the HLA–DR10 peptide repertoire was defined. A large proportion of the DR10‐associated peptides had the structural features to bind DR1 and DR4 but were theoretical nonbinders to the negatively associated alleles DR15 and DR7. Among the sequenced ligands, 10 had been reported as ligands to other RA‐associated alleles. Modeling data showed that peptide HA306–318 can bind DR1, DR4, and DR10 with similar affinities.

Conclusion

The data show the presence of common peptides in the repertoires of RA‐associated HLA alleles. The combination of the shared epitope present in DR1, DR4, and DR10 together with common putative arthritogenic peptide(s) could influence disease onset or outcome.
Onset of psoriatic arthritis in patients treated with efalizumab for moderate to severe psoriasis
Authors: Viguier Manuelle , Richette Pascal , Aubin François , Beylot‐Barry Marie , Lahfa Morad , Bedane Christophe , Delesalle Franck , Richard‐Lallemand Marie‐Aleth , Delaporte Emmanuel , Dubertret Louis , Bardin Thomas , Bachelez Hervé
Published: May 2008

Objective

To investigate the nature of polyarthritis in patients with moderate to severe psoriasis undergoing treatment with efalizumab, a humanized anti‐CD11a monoclonal antibody.

Methods

In a multicenter study, we retrospectively analyzed patients who developed arthritis during treatment with efalizumab. The relationship between joint manifestations and psoriatic disease was addressed by using different classification criteria for psoriatic arthritis (PsA). The course of arthritis and its response to treatment were also investigated.

Results

Sixteen patients developed de novo inflammatory rheumatic disease, with a mean delay of 15 weeks following the start of treatment, and with exclusive asymmetric peripheral monarthritis or oligoarthritis (8 patients), inflammatory spinal disease (1 patient), or both (7 patients), associated in some cases with enthesitis and dactylitis. All patients fulfilled at least 2 different sets of classification criteria for PsA. In most of them, an improvement in skin lesions was observed at the onset of PsA, as measured using the Psoriasis Area and Severity Index (mean score 24.88 before efalizumab versus 18.78 at the time of arthritis). Efalizumab treatment was stopped in 11 patients and was followed by the elimination of rheumatologic symptoms in 1 patient, while 8 patients required treatment with nonsteroidal antiinflammatory drugs with or without methotrexate, with 2 later being switched to tumor necrosis factor α inhibitors. Reintroduction of efalizumab (2 patients) was followed by a relapse of PsA.

Conclusion

This study questions the role of efalizumab in the induction of PsA. It also emphasizes the discrepancy between the courses of psoriatic skin and joint manifestations under treatment. Prospective case–control studies are needed to accurately investigate the impact of efalizumab on PsA.
Gene expression analysis of macrophages derived from ankylosing spondylitis patients reveals interferon‐γ dysregulation
Authors: Smith Judith A. , Barnes Michael D. , Hong Dihua , DeLay Monica L. , Inman Robert D. , Colbert Robert A.
Published: May 2008

Objective

To determine whether macrophages, a type of cell implicated in the pathogenesis of ankylosing spondylitis (AS), exhibit a characteristic gene expression pattern.

Methods

Macrophages were derived from the peripheral blood of 8 AS patients (median disease duration 13 years [range <1–43 years]) and 9 healthy control subjects over 7 days with the use of granulocyte–macrophage colony‐stimulating factor. Cells were stimulated for 24 hours with interferon‐γ (IFNγ; 100 units/ml), were left untreated for 24 hours, or were treated for 3 hours with lipopolysaccharide (LPS; 10 ng/ml). RNA was isolated and examined by microarray and real‐time quantitative reverse transcription–polymerase chain reaction analysis.

Results

Microarray analysis revealed 198 probe sets detecting the differential expression of 141 unique genes in untreated macrophages from AS patients compared with healthy controls. Clustering and principal components analysis clearly distinguished AS patients and controls. Of the differentially expressed genes, 78 (55%) were IFN‐regulated, and their relative expression indicated a “reverse” IFN signature in AS patient macrophages, where IFNγ–up‐regulated genes were underexpressed and down‐regulated genes were overexpressed. Treatment of macrophages with exogenous IFNγ normalized the expression of these genes between patients and controls. In addition, the messenger RNA encoded by the IFNγ gene was ∼2‐fold lower in AS patient macrophages at baseline (P = 0.004) and was poorly responsive to LPS (P = 0.018), as compared with healthy controls.

Conclusions

Our findings reveal consistent differences in gene expression in macrophages from AS patients, with evidence of a striking “reverse” IFN signature. Together with poor expression and responsiveness of the IFNγ gene, these results suggest that there may be a relative defect in IFNγ gene regulation, with autocrine consequences and implications for disease pathogenesis.
Effective therapy for nephritis in (NZB × NZW)F1 mice with triptolide and tripdiolide, the principal active components of the Chinese herbal remedy Tripterygium wilfordii Hook F
Authors: Tao Xuelian , Fan Fred , Hoffmann Victoria , Gao Chun Y. , Longo Nancy S. , Zerfas Patricia , Lipsky Peter E.
Published: May 2008

Objective

Triptolide and tripdiolide are thought to be active components of the Chinese antirheumatic herbal remedy Tripterygium wilfordii Hook F, which has been shown to be effective in treating murine lupus nephritis. This study was undertaken to examine the therapeutic effect of triptolide and tripdiolide on established lupus nephritis in (NZB × NZW)F1 mice.

Methods

(NZB × NZW)F1 mice were treated with vehicle, triptolide, or tripdiolide for 15 weeks beginning at the age of 29 weeks (after the development of lupus nephritis). Body weight, proteinuria, and anti–double‐stranded DNA (anti‐dsDNA) antibodies were monitored, and the kidney and spleen were assessed histologically. Culture supernatants of spleen mononuclear cells were assayed for cytokines.

Results

By 28 weeks, most (NZB × NZW)F1 mice had developed lupus nephritis. Vehicle‐treated mice exhibited progressive proteinuria, hypoalbuminemia, elevated blood urea nitrogen (BUN) levels, and evidence of severe nephritis. In contrast, proteinuria and BUN levels were significantly reduced in mice treated with either triptolide or tripdiolide as compared with those treated with vehicle. There was no hypoalbuminemia or apparent evidence of lupus nephritis in mice treated with either of the 2 diterpenoids. At 44 weeks of age, the survival rate in mice treated with vehicle (35.7%) was markedly lower than that in mice treated with either triptolide (87.5%) or tripdiolide (88.2%). The mean level of anti‐dsDNA antibody in mice treated with tripdiolide was lower than that in the vehicle‐treated mice upon completion of the treatment course. Production of tumor necrosis factor, interleukin‐6, and monocyte chemoattractant protein 1 by spleen cells was also decreased after diterpenoid therapy.

Conclusion

Therapy with triptolide or tripdiolide significantly ameliorated lupus nephritis in (NZB × NZW)F1 mice, reduced cytokine and chemokine production, and prolonged survival.