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ID PMID Title PublicationDate abstract
9210979 Percutaneous absorption and disposition studies of methotrexate in rabbits and rats. 1997 Jul The absorption and disposition of methotrexate (MTX) in the plasma, synovial fluid (SF), skin, and muscle tissue were studied following administration of a topical MTX gel in rabbits and rats. In rabbits, MTX concentrations in the plasma increased steadily toward the peak (5.9 +/- 2.8 ng mL-1) which appeared at approximately 2 h postdose and declined with the elimination half-life of 4.48 +/- 1.74 h. At 1 h after the topical dose, the MTX concentrations in the skin (49.0 +/- 19.8 micrograms g-1), muscle (12.7 +/- 3.3 ng g-1), and SF (19.2 +/- 10.1 ng g-1) underneath the dosed stifle joint were significantly higher (p < 0.05) than those of the untreated stifle joint, indicating the potential therapeutic value of topical delivery of MTX for rheumatoid arthritis. A large fraction (approximately 59%) of MTX which was found in the skin at 1 h postdose was present in the stratum corneum, indicating its extensive binding capacity for MTX. The MTX concentrations in the muscle and SF of the dosed stifle joint at 1 h postdose were 1.8 and 2.6 times higher than those in the dosed elbow joint, respectively, reflecting the effect of dose site on the permeation of MTX. Using a new filter paper method, the amounts of SF obtained from the elbow and stifle joints of four rabbits were 26.3 +/- 8.3 and 48.8 +/- 5.2 mg, respectively. A significant enhancer effect of N,N-diethyl-n-toluamide (DEET) on the disposition of MTX in the stratum corneum of rabbit ear was observed (p < 0.05) by the tape-stripping method. In rats, the gel containing 4% DEET resulted in a twofold increase in the permeation of MTX into the muscle over the 4 h period postdose. A modified HPLC method with a linear calibration curve (r > 0.999) over the range of 2-50 ng mL-1. quantitation limit of 0.5 ng mL-1, and mean recovery of approximately 87% was used for the quantitation of MTX in the tissue and fluid samples.
11440826 Diclofenac induced in vivo nephrotoxicity may involve oxidative stress-mediated massive ge 2001 Jul 15 Diclofenac (DCLF) is a nonsteroidal anti-inflammatory drug that is widely used for the treatment of osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, and acute muscle pain conditions. Toxic doses of DCLF can cause nephrotoxicity in humans and experimental animals. However, whether this DCLF-induced nephrotoxicity involves apoptotic cell death in addition to necrosis is unknown. The goals of this investigation were to determine whether DCLF-induced nephrotoxicity involves oxidative stress and apoptotic type genomic DNA fragmentation, and if so, whether DCLF-induced oxidative stress and DNA fragmentation cause apoptotic cell death in mouse kidneys. Male ICR mice (CD-1; 25-45 g), fed ad libitum, were administered nephrotoxic doses of DCLF (100, 200, 300 mg/Kg, po) and sacrificed 24 h later. Blood was collected to evaluate renal injury (BUN), lipid peroxidation (MDA: malondialdehyde levels), and superoxide dismutase (SOD) activity (a marker of oxidative stress). Kidney tissues were analyzed both quantitatively and qualitatively to determine the degree and type of DNA damage, and evaluated histopathologically for the presence of apoptotic characteristics in the nucleus of diverse types of kidney cells. Results show that diclofenac is a powerful nephrotoxicant (at 100, 200, and 300 mg/kg: 4.7-, 4.9-, and 5.0-fold increases in BUN compared to the control, respectively) and a strong inducer of oxidative stress (significant increase in MDA levels). Oxidative stress induced by DCLF was also coupled with massive kidney DNA fragmentation (100, 200, and 300 mg/kg: 3-, 8-, and 10-fold increases compared to control, respectively). A dose-dependent increase in MDA levels and SOD activity was also observed, which indicated a link between oxidative stress and nephrotoxicity. Qualitative analysis of DNA fragmentation by gel electrophoresis showed a DNA ladder indicative of Ca2+-Mg2+-endonuclease activation. Histopathological examination of kidney sections revealed numerous apoptotic nuclei across proximal and distal tubular cell linings. Collectively, these data for the first time suggest that DCLF-induced nephrotoxicity may involve production of reactive oxygen species leading to oxidative stress and massive genomic DNA fragmentation, and these two free radical mediated events may ultimately translate into apoptotic cell death of kidney cells in vivo, and reveal a DNA-active role for DCLF.
11433223 New disease-modifying antirheumatic drug 2 acetylthiomethyl-4-(4-methylphenyl)-4-oxobutano 2001 Jul We examined in this study whether the newly developed disease-modifying antirheumatic drug (DMARD) 2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (KE-298) augments activation-induced T cell death. Peripheral blood (PB) T cells, isolated from healthy donors, were activated by incubation with interleukin-2 (IL-2) followed by further culture with 12-0-tetradecanoyl phorbol 13-acetate (PMA) and ionomycin in the presence or absence of KE-298. The apoptosis of activated T cells was examined by flow cytometric determination of hypodiploid DNA. Fas expression and caspase-3 activity in activated T cells were also examined by flow cytometry, and expression of Fas ligand (FasL), Bcl-2-related proteins, and X chromosome-linked inhibitor of apoptosis protein (XIAP) was determined by Western blot analysis. Apoptosis was not obvious in resting T cells and was not augmented by KE-298. In contrast, apoptosis was clearly detected in activated T cells (activation-induced T cell death) with the increment of caspase-3 activity, and incubation of these cells with KE-298 further enhanced apoptosis. Treatment of activated T cells with KE-298 increased Bax expression but decreased XIAP expression without affecting the expression of Fas/FasL. Thus caspase-3 activity in activated T cells appeared to be increased by KE-298. Our results suggest that the newly developed DMARD, KE-298, selectively augmented activation-induced T cell death. This finding may contribute to the therapeutic efficacy of KE-298 in rheumatoid arthritis (RA) patients and provide new insight into the pharmacologic action of DMARDs.
10395706 Autoantibodies to the extracellular matrix microfibrillar protein, fibrillin-1, in patient 1999 Jul 15 A duplication in the fibrillin-1 gene has been implicated as the cause of the tight skin 1 (tsk1) phenotype, an animal model of scleroderma or systemic sclerosis (SSc). In addition to the production of abnormal fibrillin-1 protein, the tsk1 mouse also produces autoantibodies to fibrillin-1. Among a population of Choctaw Native Americans with the highest prevalence of SSc yet described, a chromosome 15q haplotype containing the fibrillin-1 gene has been strongly associated with SSc. With a recombinant human fibrillin-1 protein, autoantibodies to fibrillin-1 were detected in the sera of Native American SSc patients that correlated significantly with disease. Abs to fibrillin-1 also were detected in sera from Japanese, Caucasian, and African-American SSc patients. Compared with other ethnic groups, Japanese and Native American SSc patients had significantly higher frequencies of anti-fibrillin-1 Abs. Sera from patients with diffuse SSc, calcinosis, Raynaud's, esophageal dysmotility, sclerodactyly, and telangiectasias syndrome and mixed connective tissue disease also had significantly higher frequencies of anti-fibrillin-1 Abs than sera from controls or patients with other non-SSc connective tissue diseases (lupus, rheumatoid arthritis, and Sjögren's syndrome). Ab specificity for fibrillin-1 was demonstrated by the lack of binding to a panel of other purified autoantigens. The results presented demonstrate for the first time the presence of high levels of anti-fibrillin-1 Abs in a significant portion of patients with SSc.
10368519 Benefits and risks of oral contraceptives. 1999 Jun The major benefits of modern low-dose oral contraceptives include relative safety and a high degree of efficacy, decreasing the need for abortion or surgical sterilization; reduced risks of bacterial (but not viral) pelvic inflammatory disease and of endometrial and ovarian cancer; improved menstrual regularity, with less dysmenorrhea and blood flow; and, when low-dose combination (not progestogen-only) oral contraceptives are used, reduced acne and hirsutism. Major risks are cardiovascular. Preliminary data from nonrandomized studies suggest that oral contraceptives containing third-generation progestogens are associated with increased risk of venous thromboembolism, particularly in carriers of the coagulation factor V Leiden mutation. The risk of arterial thrombosis, such as myocardial infarction or stroke, may be directly related to estrogen dose, particularly in women who have hypertension, smoke, or are >35 years old. Considering that only users aged >/=30 years who smoke >/=25 cigarettes/d have a higher estimated mortality rate than that of pregnant women, the benefits of oral contraceptives appear to outweigh their risks.
11739498 In vivo neutralization of TNF-alpha promotes humoral autoimmunity by preventing the induct 2001 Dec 15 Neutralization of TNF-alpha in humans with rheumatoid arthritis or Crohn's disease has been associated with the development of humoral autoimmunity. To determine the effect of TNF-alpha neutralization on cell-mediated and humoral-mediated responses, we administered anti-TNF-alpha mAb to mice undergoing acute graft-vs-host disease (GVHD) using the parent-into-F(1) model. In vivo neutralization of TNF-alpha blocked the lymphocytopenic features characteristic of acute GVHD and induced a lupus-like chronic GVHD phenotype (lymphoproliferation and autoantibody production). These effects resulted from complete inhibition of detectable antihost CTL activity and required the presence of anti-TNF-alpha mAb for the first 4 days after parental cell transfer, indicating that TNF-alpha plays a critical role in the induction of CTL. Moreover, an in vivo blockade of TNF-alpha preferentially inhibited the production of IFN-gamma and blocked IFN-gamma-dependent up-regulation of Fas; however, cytokines such as IL-10, IL-6, or IL-4 were not inhibited. These results suggest that a therapeutic TNF-alpha blockade may promote humoral autoimmunity by selectively inhibiting the induction of a CTL response that would normally suppress autoreactive B cells.
11238591 Selective inhibition of vascular endothelial growth factor-mediated angiogenesis by cyclos 2001 Mar 5 Cyclosporin A (CsA) is an immunosuppressive drug that inhibits the activity of transcription factors of the nuclear factor of activated T cells (NFAT) family, interfering with the induction of cytokines and other inducible genes required for the immune response. Here we show that CsA inhibits migration of primary endothelial cells and angiogenesis induced by vascular endothelial growth factor (VEGF); this effect appears to be mediated through the inhibition of cyclooxygenase (Cox)-2, the transcription of which is activated by VEGF in primary endothelial cells. Consistent with this, we show that the induction of Cox-2 gene expression by VEGF requires NFAT activation. Most important, the CsA-mediated inhibition of angiogenesis both in vitro and in vivo was comparable to the Cox-2 inhibitor NS-398, and reversed by prostaglandin E(2). Furthermore, the in vivo corneal angiogenesis induced by VEGF, but not by basic fibroblast growth factor, was selectively inhibited in mice treated with CsA systemically. These findings involve NFAT in the regulation of Cox-2 in endothelial cells, point to a role for this transcription factor in angiogenesis, and may provide a novel mechanism underlying the beneficial effects of CsA in angiogenesis-related diseases such as rheumatoid arthritis and psoriasis.
11100810 A causal role for parvovirus B19 infection in adult dermatomyositis and other autoimmune s 2000 Nov BACKGROUND: Infection with parvovirus B19 (B19) has been associated with connective tissue disease (CTD) stigmata, namely, a systemic lupus erythematosus (SLE)-like illness, seronegative polyarthritis resembling rheumatoid arthritis, and vasculitis. The dermatopathology and pathogenetic basis of such B19-associated CTD-like syndromes have not been elucidated. OBJECTIVE: We attempted to document persistence of the B19 genome in skin lesions of 7 patients with CTD-like symptomatology following B19 infection and to correlate systemic manifestations to dermatopathological findings. METHOD: In 7 prospectively encountered patients in whom history, clinical signs and/or serology supported a diagnosis of CTD in the setting of B19 infection, dermatopathological and clinical features were correlated. Parvovirus B19 viral genome was sought in skin tissue using the polymerase chain reaction (PCR). RESULTS: Two patients had clinical features diagnostic of myopathic dermatomyositis (DM), 1 of whom is still symptomatic 1.5 years after the onset of her illness, and the other has had typical clinical features of DM for a duration of 3.5 years. A 3rd patient with SLE remains symptomatic 4 years after the onset of her illness. A 4th patient has persistent seronegative symmetrical polyarthritis of 6 years' duration and cutaneous lesions of granuloma annulare (GA). The 5th patient has a 1.5-year history of debilitating polyarthritis and cutaneous lesions with overlap features of DM and subacute cutaneous LE (SCLE). The 6th patient has had a persistent folliculocentric necrotizing vasculitis for 3 years. The 7th patient has a 1-year history of microscopic polyarteritis nodosa (PAN) with cutaneous vasculitis and persistent active renal disease. In 4 patients, exposure to children with fifth disease immediately preceded the onset of their CTD. Parvovirus B19 infection was documented serologically in 6 patients with antibodies of IgG subclass in 6 and of IgM subclass in 1. Four of 6 patients questioned had a history of atopy. Skin biopsies from patients with clinical features of SLE or DM demonstrated an interface dermatitis with dermal mucinosis. A necrotizing vasculitis with epithelial pustulation was seen in 2 patients. Interstitial GA-like infiltrates were seen in 5 cases. Immunofluorescent (IF) testing revealed a positive lupus band test (LBT) and epidermal nuclear and vascular staining for IgG and C5b-9 in the SLE patient. One DM patient had a negative LBT in concert with C5b-9 deposition along the dermoepidermal junction (DEJ) and within blood vessels while the other showed endomysial vascular Cs5b-9 deposition. In all patients, skin biopsy material contained B19 genome, which was absent in the serum of 4 patients analyzed. Symptomatic relief followed immunosuppressive and immunomodulatory therapy with agents including prednisone, cyclophosphamide, hydroxychloroquine, non-steroidal anti-inflammatory drugs and etanercept, but no patient has had complete symptom resolution. CONCLUSIONS: Persistent B19 infection may be of pathogenetic importance in certain prototypic CTD syndromes, to which underlying immune dysregulation associated with a blunted IgM response to viral antigen may predispose. Anti-viral therapy might be worthy of consideration since traditional immunosuppressive therapy was unsuccessful in our cases.
10886467 Is enough attention being given to the adverse effects of corticosteroid therapy? 2000 Jun BACKGROUND: Although the corticosteroids are valuable anti-inflammatory and immunosuppressive agents, they also possess many potential adverse effects, especially with continued use. In particular, long-term corticosteroid exposure carries a significant risk of osteoporosis. AIM: To review the use of corticosteroids in patients presenting to the major teaching hospital in Tasmania, Australia; principally to determine whether patients receiving long-term corticosteroid therapy were being monitored for loss of bone mineral density and offered preventive therapy for osteoporosis. METHODS: A retrospective review of the medical records for 212 consecutive patients admitted to the medical wards of the hospital over a 5-month period and receiving treatment with either oral or inhaled corticosteroids, was performed. An extensive range of demographic and clinical variables was recorded for each patient. Patients were also questioned about diet and exercise, and whether they had undergone tests for measuring bone mineral density or blood glucose. RESULTS: The median age of the patients was 69 years (range: 15-90 years) and 58% were female. Over half (53%) of the patients were on oral corticosteroids only, with 26% using inhaled corticosteroids only, and 21% on both oral and inhaled corticosteroid therapy. The most common conditions for which patients were receiving corticosteroid therapy were asthma (37% of patients), chronic obstructive pulmonary disease (33%) and rheumatoid arthritis (17%). The most commonly used oral corticosteroid was prednisolone (93%), the median daily dose was 10 mg prednisolone equivalent, and the median duration of oral corticosteroid treatment was 50 weeks. Disregarding short courses, the median duration of oral corticosteroid treatment was 104 weeks. Almost one-third (31%) of the patients receiving oral corticosteroid treatment had been taking the equivalent of 7.5 mg prednisolone daily for at least 6 months. Only 11% of all patients on oral corticosteroids and 21% of those who had been taking oral corticosteroids for at least one year had documented evidence of bone mineral density testing being performed in the past in the hospital. Only 21% of all patients on oral corticosteroids and 31% of those who had been taking oral corticosteroids for at least one year were receiving medication for osteoporosis prevention, and only 15% of women over 45 years of age and on oral corticosteroid therapy were taking hormone replacement therapy. Only about half of the patients on long-term systemic corticosteroid therapy had either documented evidence in their hospital medical records, or were aware, of having undergone blood glucose testing in the preceding 12 months. CONCLUSION: More attention to the prevention and monitoring of possible adverse effects of long-term corticosteroid therapy is warranted. Guidelines covering preventive measures and treatment options for corticosteroid-induced osteoporosis need to be considered routinely when using these agents.
10861084 Cyclic tensile strain acts as an antagonist of IL-1 beta actions in chondrocytes. 2000 Jul 1 Inflammatory cytokines play a major role in cartilage destruction in diseases such as osteoarthritis and rheumatoid arthritis. Because physical therapies such as continuous passive motion yield beneficial effects on inflamed joints, we examined the intracellular mechanisms of mechanical strain-mediated actions in chondrocytes. By simulating the effects of continuous passive motion with cyclic tensile strain (CTS) on chondrocytes in vitro, we show that CTS is a potent antagonist of IL-1 beta actions and acts as both an anti-inflammatory and a reparative signal. Low magnitude CTS suppresses IL-1 beta-induced mRNA expression of multiple proteins involved in catabolic responses, such as inducible NO synthase, cyclo-oxygenase II, and collagenase. CTS also counteracts cartilage degradation by augmenting mRNA expression for tissue inhibitor of metalloproteases and collagen type II that are inhibited by IL-1 beta. Additionally, CTS augments the reparative process via hyperinduction of aggrecan mRNA expression and abrogation of IL-1 beta-induced suppression of proteoglycan synthesis. Nonetheless, the presence of an inflammatory signal is a prerequisite for the observed CTS actions, as exposure of chondrocytes to CTS alone has little effect on these parameters. Functional analysis suggests that CTS-mediated anti-inflammatory actions are not mediated by IL-1R down-regulation. Moreover, as an effective antagonist of IL-1 beta, the actions of CTS may involve disruption/regulation of signal transduction cascade of IL-1 beta upstream of mRNA transcription. These observations are the first to show that CTS directly acts as an anti-inflammatory signal on chondrocytes and provide a molecular basis for its actions.
10724258 Transforming growth factor beta superfamily members: role in cartilage modeling. 2000 Mar Normal and abnormal extracellular matrix turnover is thought to result, in part, from the balance in the expression of metalloproteinases and tissue inhibitors of metalloproteinases (TIMPs). The clinical manifestations of an imbalance in these relationships are evident in a variety of pathologic states, including osteoarthritis, deficient long-bone growth, rheumatoid arthritis, tumor invasion, and inadequate cartilage repair. Articular cartilage defects commonly heal as fibrocartilage, which is structurally inferior to the normal hyaline architecture of articular cartilage. Transforming growth factor-beta 1 (TGF-beta1), a cytokine central to growth, repair, and inflammation, has been shown to upregulate TIMP-1 expression in human and bovine articular cartilage. Additionally, members of the TGF-beta superfamily are thought to play key roles in chondrocyte growth and differentiation. Bone morphogenetic protein-2 (BMP-2), a member of this superfamily, has been shown to regulate chondrocyte differentiation states and extracellular matrix composition. It was proposed that, by optimizing extracellular matrix composition, BMP-2 would enhance articular cartilage healing. After determining the release kinetics of BMP-2 from a collagen type I implant (Long-Evans male rats; two implants/rat, n = 14), it was found that, in a tissue engineering application, BMP-2 induced a hyaline-like repair of New Zealand White rabbit knee articular cartilage defects (3-mm full-thickness defects in the femoral trochlea; 2 defects/rabbit, n = 36). The quality of cartilage repair with BMP-2 (with or without chondrocytes) was significantly better than defects treated with BMP-2, as assessed by a quantitative scoring scale. Immunohistochemical staining revealed TIMP-1 production in the cartilage defects treated with BMP-2. When studied in vitro, it was found that BMP-2 markedly increased TIMP-1 mRNA by both bovine articular and human rib chondrocytes. Additionally, increased TIMP-1 mRNA was translated into increased TIMP-1 protein production by bovine chondrocytes. Taken together, these data suggest that BMP-2 may be a useful cytokine to improve healing of cartilaginous defects. Furthermore, these data suggest that the beneficial effects of BMP-2 may be, in part, related to alterations in extracellular matrix turnover.
10640396 Differential effects of interleukin-1 on hyaluronan and proteoglycan metabolism in two com 2000 Feb 1 Phenotypically stable young adult bovine articular chondrocytes suspended in beads of alginate gel were first cultured for 5 days, using daily changes of medium containing 10% fetal bovine serum and supplements. The cells in the beads were then maintained in culture for a further 3 days in the presence or absence of interleukin-1alpha at 1 ng/ml in the daily change of medium. The exposure to interleukin-1alpha caused the incorporation of (35)S-sulfate into the predominant cartilage proteoglycan, aggrecan, to decrease by approximately 60%. In addition, proteoglycans that had accumulated into the cell-associated matrix during the first 5 days of culture in the absence of interleukin-1alpha moved into the matrix further removed from the cells and from there into the medium. In contrast, the exposure to interleukin-1alpha was found to markedly promote the rate of synthesis of hyaluronan, especially during the first 24 h. Over the 3 days of culture in the presence of interleukin-1alpha, a large proportion of the newly synthesized hyaluronan molecules, as well as those that had previously become residents of the cell-associated matrix, moved out of this compartment and appeared to become permanent residents of the further removed matrix. These results demonstrate that exposure of young adult articular chondrocytes to interleukin-1alpha has profound effects on the metabolism of hyaluronan, a molecule that plays a critical role in the retention of proteoglycan molecules in the matrix. Importantly, the results suggest that exposure of chondrocytes to interleukin-1 in inflamed joints, such as occurs in rheumatoid arthritis, leads to the rapid loss of coordination of the synthesis of aggrecan and hyaluronan, two of the critical constituents of the proteoglycan aggregate. In addition, we present evidence that these interleukin-1-induced effects differentially alter the metabolism of hyaluronan in the metabolically active cell-associated matrix and the metabolically inactive matrix further removed from the chondrocytes.
10471507 Mutations in the CCN gene family member WISP3 cause progressive pseudorheumatoid dysplasia 1999 Sep Members of the CCN (for CTGF, cyr61/cef10, nov) gene family encode cysteine-rich secreted proteins with roles in cell growth and differentiation. Cell-specific and tissue-specific differences in the expression and function of different CCN family members suggest they have non-redundant roles. Using a positional-candidate approach, we found that mutations in the CCN family member WISP3 are associated with the autosomal recessive skeletal disorder progressive pseudorheumatoid dysplasia (PPD; MIM 208230). PPD is an autosomal recessive disorder that may be initially misdiagnosed as juvenile rheumatoid arthritis. Its population incidence has been estimated at 1 per million in the United Kingdom, but it is likely to be higher in the Middle East and Gulf States. Affected individuals are asymptomatic in early childhood. Signs and symptoms of disease typically develop between three and eight years of age. Clinically and radiographically, patients experience continued cartilage loss and destructive bone changes as they age, in several instances necessitating joint replacement surgery by the third decade of life. Extraskeletal manifestations have not been reported in PPD. Cartilage appears to be the primary affected tissue, and in one patient, a biopsy of the iliac crest revealed abnormal nests of chondrocytes and loss of normal cell columnar organization in growth zones. We have identified nine different WISP3 mutations in unrelated, affected individuals, indicating that the gene is essential for normal post-natal skeletal growth and cartilage homeostasis.
10359806 CCR5(+) and CXCR3(+) T cells are increased in multiple sclerosis and their ligands MIP-1al 1999 Jun 8 Multiple sclerosis (MS) is a T cell-dependent chronic inflammatory disease of the central nervous system. The role of chemokines in MS and its different stages is uncertain. Recent data suggest a bias in expression of chemokine receptors by Th1 vs. Th2 cells; human Th1 clones express CXCR3 and CCR5 and Th2 clones express CCR3 and CCR4. Chemokine receptors expressed by Th1 cells may be important in MS, as increased interferon-gamma (IFN-gamma) precedes clinical attacks, and IFN-gamma injection induces disease exacerbations. We found CXCR3(+) T cells increased in blood of relapsing-remitting MS, and both CCR5(+) and CXCR3(+) T cells increased in progressive MS compared with controls. Furthermore, peripheral blood CCR5(+) T cells secreted high levels of IFN-gamma. In the brain, the CCR5 ligand, MIP-1alpha, was strongly associated with microglia/macrophages, and the CXCR3 ligand, IP-10, was expressed by astrocytes in MS lesions but not unaffected white matter of control or MS subjects. Areas of plaque formation were infiltrated by CCR5-expressing and, to a lesser extent, CXCR3-expressing cells; Interleukin (IL)-18 and IFN-gamma were expressed in demyelinating lesions. No leukocyte expression of CCR3, CCR4, or six other chemokines, or anti-inflammatory cytokines IL-5, IL-10, IL-13, and transforming growth factor-beta was observed. Thus, chemokine receptor expression may be used for immunologic staging of MS and potentially for other chronic autoimmune/inflammatory processes such as rheumatoid arthritis, autoimmune diabetes, or chronic transplant rejection. Furthermore, these results provide a rationale for the use of agents that block CCR5 and/or CXCR3 as a therapeutic approach in the treatment of MS.
11274196 Soluble E-selectin induces monocyte chemotaxis through Src family tyrosine kinases. 2001 Jun 15 Cellular adhesion molecules such as E-selectin function to recruit leukocytes into the inflammatory lesions of diseases such as rheumatoid arthritis (RA) and atherosclerosis. Monocytes are the key components of the cellular infiltrates present in these disorders. We hypothesized that soluble E-selectin (sE-selectin) might mediate the chemotaxis of monocytes. In this report, we show that sE-selectin induced normal human peripheral blood monocyte migration in the nanomolar range in a concentration-dependent manner. Neutralization studies using RA human joint synovial fluids and anti-E-selectin antibody showed a mean 31% reduction in RA synovial fluid-mediated monocyte chemotaxis (p < 0.05), indicating that sE-selectin is a major monocyte recruiter in RA. Next, we investigated the role of tyrosine phosphorylation pathways in sE-selectin-induced monocyte chemotaxis. Human peripheral blood monocytes stimulated with sE-selectin showed a time-dependent increase in the tyrosine phosphorylation of a broad range of cellular proteins, predominantly in the molecular size range of Src family kinases (50-60 kDa) and mitogen-activated protein kinases (MAPKs). Western blot analysis of Src family kinases showed a time-dependent increase in Src, Hck, and Lyn phosphorylation. The pretreatment of monocytes with the Src inhibitor AG1879: 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolol[3,4-d]pyrimidine (PP2) prior to stimulation with sE-selectin markedly inhibited Hck and Lyn phosphorylation, whereas the phosphorylation of Src was partially inhibited. In addition, the sE-selectin stimulation of monocytes resulted in the increased phosphorylation of extracellular signal-related kinase (ERK1/2) and p38 MAPK. The pretreatment of monocytes with PP2 showed 89 and 83% inhibition of ERK1/2 and p38 MAPK phosphorylation, respectively. sE-selectin also showed a time-dependent activation of Ras kinase. Furthermore, the pretreatment of monocytes with PP2 completely inhibited sE-selectin-mediated monocyte chemotaxis. Taken together, our data demonstrate a novel function for sE-selectin as a monocyte chemotactic agent and suggest that sE-selectin might be mediating its biological functions through the Src-MAPK pathway.
11252722 The orphan nuclear receptor ROR alpha is a negative regulator of the inflammatory response 2001 Jan Retinoid-related orphan receptor alpha (ROR alpha) (NR1F1) is a member of the nuclear receptor superfamily whose biological functions are largely unknown. Since staggerer mice, which carry a deletion in the ROR alpha gene, suffer from immune abnormalities, we generated an adenovirus encoding ROR alpha1 to investigate its potential role in control of the inflammatory response. We demonstrated that ROR alpha is expressed in human primary smooth-muscle cells and that ectopic expression of ROR alpha1 inhibits TNFalpha-induced IL-6, IL-8 and COX-2 expression in these cells. ROR alpha1 negatively interferes with the NF-kappaB signalling pathway by reducing p65 translocation as demonstrated by western blotting, immunostaining and electrophoretic mobility shift assays. This action of ROR alpha1 on NF-kappaB is associated with the induction of IkappaB alpha, the major inhibitory protein of the NF-kappaB signalling pathway, whose expression was found to be transcriptionally upregulated by ROR alpha1 via a ROR response element in the IkappaB alpha promoter. Taken together, these data identify ROR alpha1 as a potential target in the treatment of chronic inflammatory diseases, including atherosclerosis and rheumatoid arthritis.
10911799 The use of laboratory tests in the diagnosis of SLE. 2000 Jun ANA IIF is an effective screening assay in patients with clinical features of SLE and will detect most anti-ssDNA, anti-dsDNA, ENAs, and other autoantibodies. False positives are common. The clinical importance cannot be extrapolated from the ANA titre or pattern, although higher titres (> 1/160) are more likely to be important. HEp-2 cells are the most sensitive substrate for ANA detection, but this must be balanced against an increased incidence of insignificant positivity. ANA positive samples should be subjected to more specific assays for the diagnosis of SLE. A combination of ENA (Ro/La/Sm/RNP) and dsDNA assays will detect most patients with SLE as long as the characteristics of the assays used are well understood. ESR and CRP measurements provide useful additional information. Sjogren's syndrome and MCTD will produce overlapping serology with SLE, and anti-dsDNA titres are sometimes seen in autoimmune hepatitis and rheumatoid arthritis. All results should be reported in the light of the clinical details, by an experienced immunologist. A suggested diagnostic protocol is outlined in fig 1. The type of assay used crucially influences the predictive value of the tests. ELISA technology dominates routine laboratory practice, but tends to produce more false positive and true weak positive results, which may reduce the PPV of the test. This can be minimised by using IgG specific conjugates and careful assay validation. The NPV for SLE [figure: see text] is high for most assays but the PPV varies. Where necessary, laboratories should use crithidia or Farr dsDNA assays to confirm dubious ELISA dsDNA results, and ID/IB to confirm dubious ENA results. For monitoring, a precise, quantitative assay is required. It is unclear whether the detection of IgM or low affinity antibodies has a role here. A combination of anti-dsDNA, C3, C4, CRP, and ESR assays provides the most useful clinical information. Anti-ssDNA assays are likely to be useful, and are potentially more robust than anti-dsDNA assays, but require more validation. Local validation of individual assays and EQA participation is essential. Not all assays that apparently measure the same antibody specificities have equal clinical relevance, even within a single technology. Insufficient international or national reference preparations are currently available for many antibody specificities to enable effective standardisation. Quality assurance schemes reveal large differences in units reported by different assays for some analytes, even when calibrated against an IRP or equivalent reference preparation. Serial results can therefore only be compared from the same laboratory at present. Most autoantibodies increase during active disease, but few prospective data are currently available to justify treatment on the basis of rising titres. Further randomised prospective studies are required to examine the importance of antibody isotype and affinity in the monitoring of SLE by individual assay methods. The most important aspect of the appropriate use of laboratory assays is to become familiar with the limitations of the technology currently in use in your local laboratory, and to consult with your clinical immunologist in cases of doubt, preferably before commencing serological screening.
10677242 Immunization of low-density lipoprotein receptor deficient (LDL-RD) mice with heat shock p 2000 Mar Heat shock proteins are a family of approximately 25 highly conserved proteins upregulated in response to various forms of stress. They play an active role in the development autoimmune diseases in animals, and have been incriminated in human autoimmune diseases (i.e. rheumatoid arthritis, multiple sclerosis). It has been previously shown, that an induced immune response against Heat shock protein 65 (HSP-65) results in atherosclerotic lesions in normocholesterolemic rabbits. We have supported these findings showing that C57BL/6 mice immunized with HSP-65 and fed a high-fat diet develop enhanced fatty streaks. To create a model that will eliminate the need for exogenous supplementation of a high-fat diet, we have immunized LDL receptor deficient (LDL-RD) mice with HSP-65 or with heat-killed Mycobacterium tuberculosis (Mt). Seven groups of LDL-RD mice (n=10), were immunized subcutaneously with different concentrations of HSP-65, Mt or bovine serum albumin (BSA). All mice were fed a normal chow-diet for 3 months. The mice immunized with the higher doses of Mt developed significantly larger fatty streaks when compared with their BSA immunized littermates. The size of the lesions in the aortic sinus were: 31,562+/-5,994 microm(2)in the 10 microg Mt and 52,777+/-5,245 microm(2)in the 100 microg Mt vs. 11, 500+/-3,750 microm(2)in the BSA group (P<0.05). In the HSP-65-immunized mice, only the group injected with the highest dose (5 microg, twice) developed significantly larger fatty streaks when compared with the BSA-immunized group (28,611+/-4,716 microm(2)vs. 11,500+/-3,750 microm(2)respectively, (P<0.05). The HSP-65-but not the Mt- or BSA-immunized mice developed high titers of anti HSP-65 antibodies, beginning 10 days after the immunization, which persisted until they were killed. Immunohistochemical staining showed CD3-positive lymphocytes in the aortic sinus of mice immunized with Mt or HSP-65, but not in the control group. Thus, we established a mouse model of HSP-65 immune mediated atherosclerosis devoid of high fat diet supplementation. This model will enable us to further study the role of the immune system in atherosclerosis, via HSP-65 and raise novel immunomodulatory therapeutic modalities.
10686819 [Angioblastic lymphadenopathy--its course and prognosis]. 1999 Nov INTRODUCTION: In recent years important advances have been made in the understanding of angioimmunoblastic lymphadenopathy since substantial controversy has been related to the name, course, prognosis and therapy of the disease. It was first recognized in the Kil Classification as a low risk T-cell lymphoma [5], and omitted from the most widely used Working Formulation for clinical purposes. According to the criteria of REAL (Revised European American Lymphoma), classification angioimmunoblastic lymphadenopathy (AILD) is one of peripheral postthymic T cell lymphomas that are an immunologically defined category of non-Hodgkin's lymphomas originating from the peripheral lymphatic tissues. Morphologically, AILD is characterized by partially or completely obliterated sinuses and frequent infiltration of the pericapsular tissue and substantial proliferation of epithelioid, postcapillary venules. Cytologically, polymorphous cellular infiltration with immunoblasts, transformed lymphoid cells, polyclonal plasma cells, eosinophils and epithelioid cells are found. Clinically, rapid occurrence of systemic symptoms in elderly individuals (sixth and seventh decades of life) with generalized lymphadenopathy, hepatosplenomegaly and cutaneous maculo-papulous or erythematous rash is noted. The patients are characterized with hyperimmune condition in the form of Coombs' positive haemolytic anaemia, polyclonal hypergamma-globulinaemia and liability to infections [8, 9]. In spite of numerous suggestions, therapeutic consensus has not been achieved, and the reported survival ranges from 1 to 30 months [10, 11]. Therefore, this information suggests an aggressive form of the disease with the 60% mortality rate. METHODS: At the Institute of Haematology of the Clinical Centre of Serbia in Belgrade in the last five years, from 1993 through August 1998, nine patients were diagnosed with AILD according to the results of pathohistological examination of the extirpated peripheral lymph nodes and the correlation with clinical picture and relevant laboratory findings. RESULTS: Clinical characteristics of nine patients in whom AILD was diagnosed after lymph node biopsy are given in Table 1. The group consisted of 6 men and 3 women, mean age 53. Eight patients were in advanced stage of the disease at the time of the diagnosis (III and IC CS), while the patient in II CS stage had a large tumorous mass (M+). All patients had initial systemic symptoms. Five of them developed fever with chills. Three patients had evidence of extranodal infiltration of the bone marrow. Infiltration of the liver was suspected in two patients according to aberrant hepatogram values, although pathohistological verification was not obtained. In one patient lung infiltration was histologically verified in addition to bone marrow and liver infiltration. All patients had peripheral lymphadenopathy, and most of them hepatosplenomegaly, as well. Three patients had the so called bulky form of the disease since the diameter of the largest tumour exceeded 10 cm. On admission, most were in poor overall condition, and only two were apparently healthy. Knowing that AILD is basically an immunoregulatory disease and that the described cases of association with systemic diseases of the connective tissue and some drugs were implied in the triggering of AILD, Table 2 shows important information obtained form histories of these patients. Namely, 7 of 9 patients had cutaneous changes suggestive of erythematous or maculopapular rash, while three had received corticosteroid therapy for months before AILD was diagnosed since toxoallergic exanthema had been incorrectly suspected. Three patients received gold sodium thiosulfate therapy for rheumatoid arthritis, while four had history of allergy to drugs and pollen. Table 3 shows laboratory results: anaemia was present in 8 of 9 patients, it was severe in three with haemoglobin values of 67 g/L, 72 g/L and 50 g/L, respectively. Five patients had haemolysis. A
10415075 Abnormal NF-kappa B activity in T lymphocytes from patients with systemic lupus erythemato 1999 Aug 1 Numerous cellular and biochemical abnormalities in immune regulation have been described in patients with systemic lupus erythematosus (SLE), including surface Ag receptor-initiated signaling events and lymphokine production. Because NF-kappa B contributes to the transcription of numerous inflammatory genes and has been shown to be a molecular target of antiinflammatory drugs, we sought to characterize the functional role of the NF-kappa B protein complex in lupus T cells. Freshly isolated T cells from lupus patients, rheumatoid arthritis (RA) patients, and normal individuals were activated physiologically via the TCR with anti-CD3 and anti-CD28 Abs to assess proximal membrane signaling, and with PMA and a calcium ionophore (A23187) to bypass membrane-mediated signaling events. We measured the NF-kappa B binding activity in nuclear extracts by gel shift analysis. When compared with normal cells, the activation of NF-kappa B activity in SLE patients was significantly decreased in SLE, but not in RA, patients. NF-kappa B binding activity was absent in several SLE patients who were not receiving any medication, including corticosteroids. Also, NF-kappa B activity remained absent in follow-up studies. In supershift experiments using specific Abs, we showed that, in the group of SLE patients who displayed undetectable NF-kappa B activity, p65 complexes were not formed. Finally, immunoblot analysis of nuclear extracts showed decreased or absent p65 protein levels. As p65 complexes are transcriptionally active in comparison to the p50 homodimer, this novel finding may provide insight on the origin of abnormal cytokine or other gene transcription in SLE patients.