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ID PMID Title PublicationDate abstract
10516777 Increased urinary nitric oxide metabolites in patients with multiple sclerosis correlates 1999 Oct Nitric oxide (NO) has been implicated in the immunopathogenesis of MS as a potential mediator of neuronal loss. To investigate the role of.NO in the development of progressive disease we measured the NO metabolites (nitrate and nitrite) and neopterin, in the urine of 129 patients with demyelinating disease (DD): 23 with clinically isolated syndromes compatible with demyelination and in 46 relapsing remitting (RR) and 60 patients with progressive MS. Eighty-nine of these 129 patients underwent Gd-enhanced MRI. In addition 58 normal control subjects (NC), 19 AIDS and 35 rheumatoid arthritis (RA) patients were studied. Patients with DD, AIDS and RA had significantly elevated urinary nitrate plus nitrite (nit : creat. urine) and neopterin (neopt : creat.urine) to creatinine ratios compared to NC subjects. (Median[25th - 75th%] nit : creat.urine: NC=1183[962 - 1365] vs DD=1245[875 - 2403], AIDS=1686[1231 - 2531], and RA=1950[1214 - 2726] mumol/mol, P<0.001 and median[25th - 75th%] neopt : creat.urine: NC=99[76 - 151] vs DD=163[119 - 266], AIDS=972[653 - 1456], and RA=389[257 - 623] mu mol/mol, P<0.001). Patients with early DD and RR MS had significantly elevated nit : creat.urine compared to patients with progressive MS (nit : creat. urine: 1612[1020 - 2733] vs 1159[790 - 1641] mu mol/mol, P=0.006). The nit : creat.urine and neopt : creat.urine did not correlate with clinical relapse or MRI activity. Excretion of.NO metabolites is increased in patients with early or relapsing-remitting disease.NO appears to be a double-edged sword, mediating tissue damage and modulating complex immunological functions which may be protective in MS.
11179355 Expression of adhesion molecules in synovia of patients with treatment-resistant lyme arth 2001 Mar The expression of adhesion molecules in synovium in patients with Lyme arthritis is surely critical in the control of Borrelia burgdorferi infection but may also have pathologic consequences. For example, molecular mimicry between a dominant T-cell epitope of B. burgdorferi outer surface protein A and an adhesion molecule, human lymphocyte function-associated antigen 1 (LFA-1), has been implicated in the pathogenesis of treatment-resistant Lyme arthritis. Using immunohistochemical methods, we examined synovial samples for expression of adhesion molecules in 29 patients with treatment-resistant Lyme arthritis and in 15 patients with rheumatoid arthritis or chronic inflammatory monoarthritis. In Lyme arthritis synovia, endothelial cells showed intense expression of P-selectin and vascular adhesion protein-1 (VAP-1). Expression of LFA-1 was also intense on infiltrating cells, particularly in lymphoid aggregates, and intercellular adhesion molecule-1 (ICAM-1) was markedly expressed on synovial lining and endothelial and infiltrating cells. Moderate expression of vascular cell adhesion molecule-1 (VCAM-1) was seen on synovial lining and endothelial cells, and mild expression of its ligand, very late antigen-4, was apparent in perivascular lymphoid infiltrates. Except for lesser expression of VCAM-1 in Lyme synovia, the levels of expression of these adhesion molecules were similar in the three patient groups. We conclude that certain adhesion molecules, including ICAM-1 and LFA-1, are expressed intensely in the synovia of patients with Lyme arthritis. Upregulation of LFA-1 on lymphocytes in this lesion may be critical in the pathogenesis of treatment-resistant Lyme arthritis.
9143347 Characterization of monoclonal antibodies recognizing different fragments of cartilage oli 1997 May 1 Cartilage oligomeric matrix protein (COMP) is a high-molecular-weight glycoprotein found at a high concentration in articular cartilage. Recent studies have shown that the joint fluid and serum levels of antigenic COMP, measured by an enzyme-linked immunosorbent assay (ELISA) which uses a polyclonal antiserum raised against bovine COMP, provide important information about metabolic changes occurring in the cartilage matrix in joint disease. In this report, we describe the specificity of three monoclonal antibodies (mAbs) to human COMP and their usefulness in quantifying antigenic COMP fragments in body fluids. Two of the mAbs (16-F12 and 18-G3) recognized both oligomeric and monomeric forms of COMP, but the third (17-C10) reacted positively only with the former. Immunoblots of human COMP, predigested with trypsin for up to 6 h, showed that the three mAbs are directed against different epitopes identified on small tryptic fragments of 30 kDa (16-F12), 25 kDa (17-C10), and 40 kDa as well as 30 kDa (18-G3), respectively. The antibodies also recognized a different pattern of fragments in human pathological synovial fluids. This was particularly striking in the case of the medium size fragments (16-F12: 90 and 110 kDa; 17-C10: 70 and 90 kDa; 18-G3: up to five bands from 70 to 130 kDa). Competitive indirect inhibition ELISAs developed with mAbs 16-F12 and 17-C10 revealed further differences in the specificities of these antibodies. Thus, while mAb 16-F12 can be used only to quantify antigenic COMP in human synovial fluid and serum, mAb 17-C10 is useful in addition when analyzing canine and horse synovial fluid as well as canine serum. The results of analyses of synovial fluid samples from patients with osteoarthritis and rheumatoid arthritis provided preliminary evidence in support of the contention that measurement of the different COMP epitopes recognized by these mAbs in body fluids could prove useful in the clinical assessment of patients with joint disease.
10092109 Interferon-beta mediates stromal cell rescue of T cells from apoptosis. 1999 Mar The resolution of immune responses is characterized by extensive apoptosis of activated T cells. However, to generate and maintain immunological memory, some antigen-specific T cells must survive and revert to a resting G0/G1 state. Cytokines that bind to the common gamma chain of the IL-2 receptor promote the survival of T cell blasts, but also induce proliferation. In contrast, soluble factors secreted by stromal cells induce Tcell survival in a resting G0/G1 state. We now report that interferon-beta is the principal mediator of stromal cell-mediated Tcell rescue from apoptosis. Interferon-alpha and -beta promote the reversion of blast Tcells to a resting G0/G1 configuration with all the characteristic features of stromal cell rescue; such as high Bcl-XL expression and low Bcl-2. Type I interferons and stromal cells stimulate apparently identical signaling pathways, leading to STAT-1 activation. We also show that this mechanism may play a fundamental role in the persistence of T cells at sites of chronic inflammation; suggesting that chronic inflammation is an aberrant consequence of immunological memory.
9226177 Lymphomas in patients with Sjogren's syndrome are marginal zone B-cell neoplasms, arise in 1997 Jul 15 The occurrence of non-Hodgkin's lymphoma (NHL) is the most serious complication of Sjogren's syndrome (SS). We performed a study of 16 NHLs occurring in patients with an underlying SS. These lymphomas arose not only in salivary glands (7 cases) but also in other mucosal extranodal sites (the stomach [4 cases], the lung [3 cases], the skin [3 cases], the buccal mucosa [1 case], the thymus [1 case]) and in nodal sites (8 cases). Low-grade marginal zone lymphomas (MZL) were diagnosed in 12 of the 16 patients, 9 of mucosa-associated lymphoid tissues (MALT) type in mucosal sites and 3 exclusively nodal. The 4 other patients presented with a high-grade B-cell lymphoma that was probably a histological transformation of an underlying low-grade MZL at least in 3 of the cases involving skin, stomach, and parotid, respectively. A t(14;18) translocation was detected in 1 of 8 lymphomas tested. We detected serum anti-p53 antibodies in 2 of the 14 studied patients. p53 protein was detected in 1 of 11 lymphomas tested. LMP protein and Eber RNAs of Epstein-Barr virus (EBV) were not detected in the 16 NHL biopsies. Using polymerase chain reaction, EBV was never detected except in 1 of 4 parotid lymphomas. No human T-lymphotropic virus 1 or human herpes virus 8 DNAs were detected in NHL biopsies. None of the patients had hepatitis C virus infection found using serological methods. Chemotherapy was usually efficient. In conclusion, lymphomas occurring in patients with an underlying SS are in most cases MZL. These lymphomas are not associated with viruses known to be present in other types of lymphomas. Some of the translocations or mutations of oncogenes or antioncogenes described in other lymphomas are detected in SS-associated lymphomas.
10617637 Macrophage migration inhibitory factor up-regulates expression of matrix metalloproteinase 2000 Jan 7 Neutral matrix metalloproteinases (MMPs) are responsible for the pathological features of rheumatoid arthritis (RA) such as degradation of cartilage. We herein show the up-regulation of MMP-1 (interstitial collagenase) and MMP-3 (stromelysin) mRNAs of cultured synovial fibroblasts retrieved from rheumatoid arthritis (RA) patients in response to macrophage migration inhibitory factor (MIF). The elevation of MMP-1 and MMP-3 mRNA was dose-dependent and started at 6 h post-stimulation by MIF, reached the maximum level at 24 h, and was sustained at least up to 36 h. Interleukin (IL)-1beta mRNA was also up-regulated by MIF. These events were preceded by up-regulation of c-jun and c-fos mRNA. Tissue inhibitor of metalloproteinase (TIMP)-1, a common inhibitor of these proteases, was slightly up-regulated by MIF. Similarly, mRNA up-regulation of MMP-1 and MMP-3 was observed in the synovial fibroblasts of patients with osteoarthritis. However, their expression levels were much lower than those of RA synovial fibroblasts. The mRNA up-regulation by MIF was inhibited by the tyrosine kinase inhibitors genestein and herbimycin A, as well as the protein kinase C inhibitors staurosporine and H-7. On the other hand, the inhibition was not seen after the addition of the cyclic AMP-dependent kinase inhibitor, H-8. The mRNA up-regulation of MMPs was also inhibited by curcumin, an inhibitor of transcription factor AP-1, whereas interleukin-1 receptor antagonist, an IL-1 receptor antagonist, failed to inhibit the mRNA up-regulation. Considering these results, it is suggested that 1) MIF plays an important role in the tissue destruction of rheumatoid joints via induction of the proteinases, and 2) MIF up-regulates MMP-1 and MMP-3 via tyrosine kinase-, protein kinase C-, and AP-1- dependent pathways, bypassing IL-1beta signal transduction.
11204935 Piroxicam concentrations in plasma and synovial fluid after a single dose of piroxicam-bet 2001 Jan AIMS: The efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) in rheumatic diseases depends on their concentrations within the joint. We determined piroxicam concentrations in plasma and synovial fluid (SF) after a single oral dose of 20 mg in the form of one tablet of piroxicam-beta-cyclodextrin. METHODS: 45 patients, aged 21 to 84 years, presenting with an effusion of the knee, related to degenerative or inflammatory joint disease, were included in this study after having given their written consent. One blood and one SF sample were drawn concomitantly in each patient from 0.5 to 48 h after NSAID administration. Piroxicam assays were performed by high performance liquid chromatography. Pharmacokinetic parameters were obtained from the mean plasma and synovial concentrations measured at various sampling times. RESULTS: The peak concentration was higher in plasma (2.51+/-0.25 microg/ml) than in SF (1.31+/-0.76 microg/ml), but the elimination half-life was much longer in SF (90.7 h) than in plasma (32.5 h). The SF/plasma area under the concentration-time curve ratio (evaluating the quantity of NSAID transferred from the blood to the joint) was equal to 0.39. CONCLUSIONS: Piroxicam contained in piroxicam-beta-cyclodextrin diffused well into the SF where its pharmacokinetic profile corresponded to that of a long half-life NSAID.
11449408 Evaluation of monensin and brefeldin A for flow cytometric determination of interleukin-1 2001 Jun 15 Flow cytometry has become a powerful technique to measure intracellular cytokine production in lymphocytes and monocytes. Appropriate inhibition of the secretion of the produced cytokines is required for studying intracellular cytokine expression. The aim of this study was to compare the capacity of cytokine secretion inhibitors, monensin and brefeldin A, in order to trap cytokine production (interleukin-1 beta [IL-1beta], IL-6, tumor necrosis factor-alpha [TNF-alpha]) within peripheral blood monocytes. A two-color flow cytometric technique was used to measure intracellular spontaneous and lipopolysaccharide (LPS)-stimulated IL-1beta, IL-6, and TNF-alpha production in monocytes (CD14+) of whole blood cultures. The viability of monensin-treated monocytes was slightly lower than that of brefeldin A-inhibited monocytes, as measured with propidium iodide (PI). The percentage of IL-6 and TNF-alpha-producing monocytes after 8 h of culture without stimulation revealed significant lower values for monensin-treated than for brefeldin A-treated monocytes. The percentages for stimulated cells did not differ. The spontaneous intracellular production in molecules of equivalent soluble fluorochrome units (MESF) of IL-1beta, IL-6, and TNF-alpha after 8 h of culture was higher in brefeldin A than in monensin-inhibited monocytes. The LPS-stimulated intracellular production of IL-1beta, IL-6, and TNF-alpha was increased in brefeldin A-inhibited monocytes. In conclusion, for flow cytometric determination of intracellular monocytic cytokines (IL-1beta, IL-6, and TNF-alpha), brefeldin A is a more potent, effective, and less toxic inhibitor of cytokine secretion than monensin.
9503526 [Clinical significance of Willebrand's factor antigen in patients with primary Sjogren's s 1997 Concentration of von Willebrand's factor antigen (WFAg) was measured by solid phase enzyme immunoassay in the blood serum of 17 female patients (mean age 56.7 +/- 12.1 years) with primary Sjogren's syndrome (PSS) lasting, on the average, 4.1 +/- 1.5 years. Mean WFAg level in patients with PSS was equal to 2.56 +/- 1.4 IU/ml and exceeded significantly that of donors' (1.06 +/- 0.34, p < 0.001). In 9(53%) of 17 patients WFAg concentration was higher than normal (> 2.1 IU/ml). WFAg mean levels and frequency of its elevation did not differ significantly in patients with chronic parotitis, enlarged salivary glands, arthralgia/arthritis, lymphadenopathy, lung lesions, polyneuropathy and patients free of the above symptoms. In patients with myalgia, Raynaud's syndrome, skin vasculitis and vascular diseases WFAg concentrations were higher than in patients without them. There was no significant correlation between WFAg level and ESR, concentration of C-reactive protein, presence of rheumatoid and antinuclear factors.
9539304 Desmopressin and low-dose ACTH test in rheumatoid arthritis. 1998 Mar OBJECTIVE: To ascertain whether a different regulation and sensitivity of the hypothalamic-pituitary-adrenal axis exists and whether a type of cortisol resistance is present in rheumatoid arthritis (RA) patients, a chronic disease in whose pathogenesis modifications of the steroid milieu are involved. DESIGN: We studied the basal and dynamic response of ACTH and adrenal steroids to various stimuli acting on the hypophysis or directly on the adrenal gland. METHODS: We studied ten RA patients (39.8 +/- 7.4 (S.D.) years), defined according to the American Rheumatism Association, and seven healthy control patients (34.1 +/- 9.6 (S.D.) years). All subjects underwent testing, in random order, with placebo, desmopressin (DDAVP) (10 microg i.v.), ovine corticotropin-releasing hormone (oCRH) (1 microg/kg body weight) and low-dose ACTH (5 microg i.v.), during the follicular phase of two different menstrual cycles. Blood samples were collected at different times for ACTH and adrenal steroids assay. Baseline estradiol (E2), testosterone and IGF-I levels were also evaluated. All subjects collected urine specimens for 24 h urine free cortisol (UFC). RESULTS: No difference in E2, testosterone or UFC was found between RA patients and controls. IGF-I levels were significantly (P < 0.01) lower in RA patients (110.6 +/- 6.4 microg/l) than in controls (207.0 +/- 37.9 microg/l). Mean baseline dehydroepiandrosterone (DHEA) and delta4-androstenedione levels of the four tests were significantly (P < 0.05) lower in RA patients than in controls. In RA, a negative correlation was found between mean DHEA levels, class of disease (r = -0.67, P < 0.05) and erythrocyte sedimentation rate (r = -0.63, P < 0.05). After placebo no difference in ACTH and cortisol area under curves (AUCs) was found between RA patients and controls. After DDAVP no cortisol or ACTH response was found in RA patients, while a significant (P < 0.05) ACTH release was found in controls. Only in RA patients was DDAVP able to induce a significant (P < 0.01) DHEA increase. After oCRH a similar significant response in ACTH (P < 0.05), cortisol (P < 0.01), and DHEA (P < 0.01) was found in both groups. After low-dose ACTH, a similar significant (P < 0.01) cortisol response was found in both RA patients and controls; indeed in RA patients DHEA AUC (2196.0 +/- 321.8 nmol/l per 90 min) was significantly lower (P < 0.01) than DHEA AUC (4280.8 +/- 749.0 nmol/l per 90 min) in controls. A similar significant (P < 0.01), though not abnormal, 17-hydroxyprogesterone response to ACTH was found in both groups. CONCLUSIONS: Our study underlines reduced adrenal steroid and IGF-I levels, but not the previously described cortisol resistance in RA patients; it shows that baseline and dynamic cortisol levels are 'normal' but inadequate in the setting of a sustained inflammatory disease like RA. The reduced basal and low-dose ACTH-induced DHEA levels could reflect both a reduced sensitivity of the adrenal gland to exogenous corticotropin and a decreased steroid synthesis due to a partial adrenal enzymatic defect (P450 17,20 lyase).
10643703 Autoantibodies to DEK oncoprotein in human inflammatory disease. 2000 Jan OBJECTIVE: To evaluate the specificity of anti-DEK antibodies for juvenile rheumatoid arthritis (JRA). METHODS: Anti-DEK autoantibodies were measured by enzyme-linked immunosorbent assay (ELISA) using affinity-purified his6-DEK fusion protein. Sera from 639 subjects (417 patients with systemic autoimmune disease, 13 with sarcoidosis, 44 with pulmonary tuberculosis, 125 with uveitis, and 6 with scleritis, and 34 healthy control subjects) were screened. Reactivity was verified by immunoblotting and immunoprecipitation studies using baculovirus-expressed human DEK. RESULTS: Anti-DEK activity was found at the following frequencies: JRA 39.4% (n = 71), systemic lupus erythematosus (SLE) 25.1% (n = 216), sarcoidosis 46.2% (n = 13), rheumatoid arthritis 15.5% (n = 71), systemic sclerosis 36.0% (n = 22), polymyositis 6.2% (n = 16), and adult Still's disease 0% (n = 21). Autoantibodies also were detected in 9.1% of tuberculosis sera (n = 44), but were undetectable in sera from the 34 healthy controls. Western blot and immunoprecipitation assay results correlated well with the ELISA findings. In general, levels of anti-DEK autoantibodies were higher in SLE than in other patient subsets, including JRA. CONCLUSION: Anti-DEK autoantibodies are less specific for JRA than previously believed. They are produced in association with a variety of inflammatory conditions, many of which are associated with granuloma formation and/or predominant Thl cytokine production. Anti-DEK antibodies may be a marker for a subset of autoimmunity associated with interferon-gamma production rather than a particular disease subset.
11094640 Anti-inflammatory effects of a stabilized lipid extract of Perna canaliculus (Lyprinol). 2000 Sep A lipid-rich extract, prepared by supercritical fluid (CO2) extraction of freeze-dried stabilized NZ green-lipped mussel powder (Lyprinol) has shown significant anti-inflammatory (AI) activity when given to animals and humans. When treated p.o. with Lyprinol, Wistar and Dark Agouti rats developed neither adjuvant-induced polyarthritis or collagen(II)-induced auto-allergic arthritis. This was achieved with doses < NSAIDs, and 200 times < of other seed or fish oils. Lyprinol subfractions inhibited LTB4 biosynthesis by PMN in vitro, and PGE2 production by activated macrophages. Much of this AI activity was associated with omega-3 PUFAs and natural antioxidants [e.g. carotenoids]. In contrast to NSAIDs, Lyprinol is non-gastro toxic in disease-stressed rats at 300 mg/kg p.o., and does not affect platelet aggregation [human, rat]. Clinical studies, either controlled or randomized, have demonstrated very significant AI activity in patients with osteoarthritis (OA), rheumatoid arthritis (RA), asthma, and other inflammatory conditions. Lyprinol is a reproducible, stable source of bioactive lipids with much greater potency than plant/marine oils currently used as nutritional supplements to ameliorate signs of inflammation.
9770330 Different roles of tumour necrosis factor alpha and interleukin 1 in murine streptococcal 1998 Sep In this study two different aspects of tumour necrosis factor alpha (TNF-alpha) and interleukin 1 (IL-1) in locally induced murine streptococcal cell wall arthritis (SCW) were investigated. First, the kinetics and interdependence of TNF-alpha and IL-1 release; and second; their involvement in inflammation and cartilage destruction. Kinetic studies showed that the TNF-alpha peak level preceded the IL-1 peak level. However, in vivo neutralization of TNF-alpha did not result in decreased IL-1 bioactivity or immunoreactivity, suggesting that there is no dominant TNF-alpha-dependent IL-1 release in this model. Inflammation was studied by measuring knee joint swelling and inflammatory cell influx. Impact on cartilage was studied by measuring chondrocyte proteoglycan synthesis and cartilage proteoglycan depletion. The role of TNF-alpha in these phenomena was investigated using anti-TNF-alpha antibodies and tumour necrosis factor binding protein (TNFbp). Similarly, the role of IL-1 was studied using anti-IL-1 antibodies or IL-1 receptor antagonist (IL-1Ra). Anti-TNF-alpha treatment significantly reduced joint swelling, whereas this effect was not found by using anti-IL-1 or IL-1Ra. In contrast, neutralization of IL-1, but not TNF-alpha, resulted in a significant decrease of chondrocyte proteoglycan synthesis inhibition. Moreover, histology revealed that anti-IL-1 treatment reduced cartilage proteoglycan depletion and inflammatory cell influx. Combined anti-TNF-alpha/anti-IL-1 treatment significantly suppressed both inflammation and cartilage damage. However, the impact on these separate parameters did not exceed the effects of either anti-TNF-alpha or anti-TNF-1. It can be concluded that both TNF-alpha and IL-1 exert specific activities in SCW arthritis. The involvement of TNF-alpha in this model is limited to joint swelling, whereas IL-1 plays a dominant role in cartilage destruction and inflammatory cell influx.
9890678 Serum soluble Fas/APO-1 is increased in patients with primary Sjögren's syndrome. 1998 The aim of the study was to elucidate the involvement of Fas antigen in human autoimmune disease, by analysing serum levels of soluble Fas/APO-1 protein in patients with various autoimmune diseases, including system lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc), polymyositis/dermatomyositis (PM/DM), Behçet's syndrome and Sjögren's syndrome (SjS). The levels of soluble Fas/APO-1 in sera were quantitated by a sandwich enzyme-linked immunosorbent assay. Soluble Fas/APO-1 levels were significantly increased in serum from patients with primary Sjögren's syndrome (primary SjS) compared with control subjects. However, no significant differences in soluble Fas/APO-1 levels were noted in patients with secondary Sjögren's syndrome (secondary SjS) nor in patients with any of the other autoimmune diseases. The soluble Fas/APO-1 level in primary SjS patients with extraglandular diseases was significantly higher than that in patients without extraglandular diseases. These results suggest that soluble Fas/APO-1 protein may play an important role in the pathogenesis of primary SS.
9169591 Modified proenzymes as artificial substrates for proteolytic enzymes: colorimetric assay o 1997 May 1 We describe a new principle for assessment of the activity of proteolytic enzymes of all classes and show the application of this principle for the quantitative assay of bacterial collagenase and human matrix metalloproteinases (MMPs). Central to this new principle is the presence of a proenzyme that can be activated into an active enzyme by a single proteolytic event. The regular activation sequence in the proenzyme is replaced using protein engineering by an artificial sequence recognized by the proteinase to be determined. The latter can act as an activator for the newly engineered proenzyme. In the present paper a simple colorimetric assay for the determination for MMPs is described based on this principle. With the aid of protein engineering, a modified pro-urokinase has been prepared in which the activation sequence normally recognized by plasmin (Pro-Arg-Phe-Lys upward arrowIle-Ile-Gly-Gly) has been replaced by a sequence expected to be recognized and hydrolysed by many MMPs (Arg-Pro-Leu-Gly upward arrowIle-Ile-Gly-Gly). The active urokinase resulting from activation of the modified pro-urokinase by a MMP could be measured either directly, using a specific chromogenic peptide substrate for urokinase, or indirectly via urokinase-catalysed plasminogen activation. The response of the assay to equal molar quantities of active MMPs decreases in the order MMP-2>MMP-9>MMP-1>MMP-3>MMP-7. The detection limit for MMP-9 was below 15 pM, corresponding to 3. 75x10(-15) mol per assay. Using the assay, increased MMP activity was detected in synovial tissue extracts from rheumatoid arthritis patients compared with those from osteoarthritis patients, and in stomach tumour extracts as compared with normal stomach tissue extracts.
10763094 Other smoking-affected pulmonary diseases. 2000 Mar Cigarette smoking is the leading cause of preventable death in the United States. Smoking adversely affects many organ systems, but especially the lung. Carcinoma of the lung and chronic obstructive pulmonary disease account for most smoking-associated respiratory morbidity and mortality, and their association with smoking is both well established and widely recognized. Cigarette smoking also is associated with differences in the incidence, severity, or natural history of a broad array of other respiratory illnesses, ranging from the common cold to pneumothorax, pulmonary hemorrhage, and various interstitial lung diseases. Interestingly, while the general effect of smoking on respiratory diseases is adverse, in the cases of sarcoidosis and hypersensitivity pneumonitis smoking may actually be associated with a decrease in the incidence of disease. In this article, the author briefly discusses some of the pulmonary and systemic effects of smoking that might mediate its effects on an array of lung diseases, then comprehensively reviews less common or less well-recognized smoking-affected lung diseases such as pulmonary infections, spontaneous pneumothorax, Goodpasture's syndrome, eosinophilic granuloma and other interstitial lung diseases, and pulmonary metastatic disease.
9876901 Comparative study of serum and synovial fluid interleukin-11 levels in patients with vario 1998 Nov OBJECTIVE: To determine the levels of serum and synovial fluid (SF) interleukin (IL)-11 in patients with various arthritides and estimate the contribution of IL-11 to acute phase response (APR). DESIGN AND METHODS: Serum and SF IL-11 were measured by ELISA in patients with rheumatoid arthritis (RA, n = 31), seronegative spondyloarthritis (SSA, n = 23), gout (GT, n = 14) and osteoarthritis (OA, n = 20) and were correlated with ESR and acute phase proteins as well as with cytokines IL-1 alpha, IL-1 beta, IL-6, and TNF alpha. RESULTS: IL-11 was detected in both serum and SF in each group, with IL-11 being statistically higher in SF than serum in all groups, suggesting reduced catabolism or increased synthesis of IL-11 intra-articularly. Median SF IL-11 levels were higher in OA patients than in other groups and in the treated than in the untreated RA subgroup. Moreover, serum and SF IL-11 were correlated significantly with each other, and moderately with the other cytokines examined in RA, SSA, and GT, but not in OA patients, while a significant negative correlation was found with a few of the inflammatory markers examined in each group. CONCLUSIONS: Our findings provide evidence of extensive intra-articular expression of IL-11 in arthritides, especially in OA and treated RA patients, suggesting a protective role for IL-11 in joints, probably through the induction of tissue inhibitor of metalloproteinases.
9558159 Transforming growth factor-beta and platelet derived growth factor regulation of fibrillar 1998 Apr OBJECTIVE: To investigate factors regulating fibronectin fibrillar matrix formation by synovial fibroblasts. METHODS: Basal and cytokine stimulated extracellular matrix (ECM) fibronectin produced by synovial fibroblasts was identified by immunofluorescence and Western blot. Alternative mRNA splicing of fibronectin was studied by reverse transcription polymerase chain reaction. The integrin receptor responsible for supporting fibronectin fibrillar matrix was identified by blocking antibodies and receptor levels studied by Western blot. RESULTS: Transforming growth factor-beta (TGF-beta) or platelet derived growth factor (PDGF), but not interleukin 1 or exogenous fibronectin, induced ECM fibronectin. ECM fibronectin was blocked by the addition of antibody to the alpha5beta1 integrin. Cytokines did not significantly change alternative mRNA splicing of fibronectin or levels of alpha5beta1 integrin expression. CONCLUSION: Synovial cell production of a fibrillar fibronectin matrix is induced by growth factors, including TGF-beta and PDGF. This induction is mediated by the alpha5beta1 integrin. Since fibrillar fibronectin formation was not strongly dependent on increased fibronectin or alpha5beta1 integrin levels, this effect may be mediated by growth factor induced changes in receptor affinity.
9569069 Co-culture of synovial fibroblasts and differentiated U937 cells is sufficient for high in 1998 Feb Inflamed synovium is characterized by high concentrations of cytokines [interleukin (IL)-6, IL-1beta and tumour necrosis factor (TNF)-alpha] and the abundant presence of infiltrated monocytes, many of which are found adjacent to the resident fibroblast-like synoviocytes. We have used a co-culture of fibroblast-like synoviocytes and differentiated U937 cells to study IL-6, IL-1beta and TNF-alpha release. After a 3 day co-culture, 35% of the U937 cells had adhered and were fully differentiated towards monocytes, as determined by expression of p47phox, CD14, MSE-1, Mac-1, collagenase and NADPH oxidase activity. IL-6 release from fibroblast-like synoviocytes was induced 4-fold by co-culture with differentiated U937 cells. However, co-culture of differentiated U937 cells with fibroblast-like synoviocytes failed to release detectable levels of IL-1beta and TNF-alpha from the U937 cells. Addition of synovial fluid further increased IL-6 release, but again had no effect on IL-1beta or TNF-alpha, although U937 cells differentiated by phorbol ester were able to release these two cytokines and, in the case of the co-culture, mRNAs for both cytokines were highly expressed in the U937 cells. We postulate that the influx of monocytes into the synovium is instrumental in the elevation of IL-6 levels, but this is not sufficient to explain high levels of IL-1beta or TNF-alpha.
9449712 Mycoplasma superantigen is a CDR3-dependent ligand for the T cell antigen receptor. 1998 Feb 2 Superantigens are defined as proteins that activate a large number of T cells through interaction with the Vbeta region of the T cell antigen receptor (TCR). Here we demonstrate that the superantigen produced by Mycoplasma arthritidis (MAM), unlike six bacterial superantigens tested, interacts not only with the Vbeta region but also with the CDR3 (third complementarity-determining region) of TCR-beta. Although MAM shares typical features with other superantigens, direct interaction with CDR3-beta is a feature of nominal peptide antigens situated in the antigen groove of major histocompatibility complex (MHC) molecules rather than superantigens. During peptide recognition, Vbeta and Valpha domains of the TCR form contacts with MHC and the complex is stabilized by CDR3-peptide interactions. Similarly, recognition of MAM is Vbeta-dependent and is apparently stabilized by direct contacts with the CDR3-beta region. Thus, MAM represents a new type of ligand for TCR, distinct from both conventional peptide antigens and other known superantigens.