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ID PMID Title PublicationDate abstract
10661386 Cartilage oligomeric matrix protein (COMP) levels in digital sheath synovial fluid and ser 2000 Jan Cartilage oligomeric matrix protein (COMP) is a noncollagenous extracellular matrix protein found predominantly in cartilage, but also in tendon, ligament and meniscus. Studies in man have demonstrated that it may be used as a prognostic marker in rheumatoid arthritis and osteoarthritis. The present study investigated whether tendon injury contributes to serum and tendon sheath synovial fluid levels of COMP in horses. COMP levels, analysed by competitive ELISA, in the digital sheath synovial fluid were more than 10-fold higher than in the serum. Levels were significantly raised when tendon damage or sepsis was present within the tendon sheath but showed only mild, statistically insignificant, elevation in cases of tenosynovitis alone. COMP concentrations in serum were found to vary with age. Foals (age < or = 1 year) had significantly (P<0.001) higher levels in comparison to older control horses. Total COMP concentrations in an age-matched group with tendinitis were not significantly different from the control group. Measurements of COMP levels in tendon sheath synovial fluid are therefore useful in depicting processes in tendon tissue, while elevated serum levels are likely to be more representative of joint disease than tendinitis.
10585302 Thyroid disorders in female patients with ankylosing spondylitis. 1999 Nov 22 The association between rheumatological and thyroid disorders has long been known, the most common being the association of rheumatoid arthritis and autoimmune thyroiditis. Little is known as to possible thyroid involvement in ankylosing spondylitis (AS). In 22 female patients with AS and 22 healthy age-matched control subjects parameters of thyroid gland function, rheumatic activity, as well as a subtle drug anamnesis of the rheumatic medication, and an ultrasonographic examination of the thyroid gland were determined. Thyroid function was tested by intravenous injection of 400 microg thyrotropin-releasing hormone (TRH). In parallel basal levels of reverse-T3 (rT3), calcium and anti-thyroid antibodies were estimated. In the AS-group an enlarged thyroid volume was seen in 10 cases, basal FT4, FT3 and TT3 were significantly lower, TSH and TT4 were found to be in the normal range and rT3 was significantly increased. The prevalence of anti-thyroid antibodies was significantly higher in the AS-group. The AS-patients responded as well as the controls with thyroid hormone secretion to TRH, within an observation period of 2 hours. No differences were observed in TSH response. Free serum calcium showed in both groups no significant difference. To summarize our results, female patients with AS showed a
10476927 Autoimmunity is a type I interferon-deficiency syndrome corrected by ingested type I IFN v 1999 Aug Type I interferons (IFN-alpha/beta), products of the innate immune system, can modulate immune function whereas proinflammatory IFN-gamma (type II IFN), a product of the acquired immune system upregulates inflammation and enhances cell mediated immunity. We have proposed a unifying hypothesis of the origin of autoimmunity as a type I IFN immunodeficiency syndrome involving inadequate regulation of the acquired immune system product IFN-gamma by the IFN-alpha/beta innate immune system. The common theme of ingested type I IFNs in autoimmunity is inhibition of proinflammatory type II IFN systemically or at the target organ. In multiple sclerosis (MS) and insulin-dependent diabetes mellitus (IDDM) at the target organ, and in rheumatoid arthritis (RA) as a regulator of other proinflammatory cytokines, IFN-gamma is the nexus of inflammation in autoimmunity. Ingested type I IFNs counteract type II IFN, overcome the relative lack of type I IFN activity, and ameliorate autoimmunity. The administration of type I IFNs (IFN-alpha/beta) via the gut offers an exciting alternative to systemic application for overcoming the type I IFN immunodeficiency in autoimmunity. Successful use of ingested type I IFN in three separate prototypical autoimmune diseases suggests a broad antiinflammatory therapeutic profile for this technology.
10434529 [Criteria and modalities of assessment of work fitness for jobs in food industry]. 1999 May Current legislation establishes the general methods and standards of judgement concerning fitness of workers to perform particular jobs. The object of this study was to verify particular criteria and methods that, in observance of the law, allow the physician to maintain in productive activity workers with chronic disease or permanent consequences of industrial accidents in Apulia, Southern Italy. In accordance with the law, 156 workers and their work environment are regularly under surveillance. In the last few years it was possible to accurately diagnose all diseases that may be involved in particular work fitness checks. 3 workers suffered the permanent consequences of very serious labour accidents amputation of II, III, IV fingers of the right hand; a slight post-traumatic shortening (shrinkage) of the right femur; tympanic membrane perforation). 7 workers suffered from non-work related disease (substitution of aortic valve, allergic asthma, virus B chronic hepatitis, chronic glomerulonephritis, replacement of right knee, rheumatoid arthritis, thrombosis of the retinal central vein without a vision reduction). The criteria for an "fitness judgement" are: an accurate diagnosis and evaluation of residual functional ability, analysis of the original job, with an investigation in the field, and break down into the single operations in order to assess all work-related risks (concerning health, safety and physical resources), and evaluation of work organization per job. It was thus possible to define particular adjustments to the original job, so as to be compatible with the current physical conditions the workers. Workers, factory directors and union officers accepted these particular criteria and standard of "work fitness judgement, which made it possible to apply them in practice with consequent reinstatement of workers in productive activity.
10102520 Morphological and biochemical analysis of anti-nuclear matrix protein antibodies in human 1999 Feb Autoimmune sera have been used in the diagnosis of autoimmune diseases as well as the analysis of nuclear substructures. In an attempt to study the biological characteristics of the nuclear matrix, we screened human sera using immunofluorescent staining and immunoblot. We detected antibodies against nuclear matrix (NM), a remnant nonchromatin protein compartment after the treatment of detergent, salt and nuclease, in 212 out of 284 tested sera (74.6%) by immunoblot. Peptides with molecular weights of 70 kDa, 50 kDa and 25 kDa were detected in the order of frequency. Clinical informations of 198 out of 212 cases were available and went as follows: 38 cases were autoimmune diseases, such as systemic lupus erythematosus and rheumatoid arthritis; 132 non-autoimmune and non-neoplastic diseases; 16 neoplastic diseases and 12 cases unclassified. The immunofluorescent staining intensity by anti-nuclear matrix protein (NMP) antibodies decreased variably, but fibrillogranular, speckled and nucleolar immunolocalization patterns were retained after in situ fractionation. Ku70 and La protein were detected by anti-NMP antibodies. Immunolocalization by anti-NMP antibodies indicates that the NMPs constitute a variety of characteristic nuclear substructures and may serve as autoantigens in diverse human diseases. In addition, the presence of Ku70 and La protein as NMPs suggests that the NM can be functionally active in association with DNA or RNA.
9892215 Role of oxidative stress in diabetic complications: a new perspective on an old paradigm. 1999 Jan Oxidative stress and oxidative damage to tissues are common end points of chronic diseases, such as atherosclerosis, diabetes, and rheumatoid arthritis. The question addressed in this review is whether increased oxidative stress has a primary role in the pathogenesis of diabetic complications or whether it is a secondary indicator of end-stage tissue damage in diabetes. The increase in glycoxidation and lipoxidation products in plasma and tissue proteins suggests that oxidative stress is increased in diabetes. However, some of these products, such as 3-deoxyglucosone adducts to lysine and arginine residues, are formed independent of oxidation chemistry. Elevated levels of oxidizable substrates may also explain the increase in glycoxidation and lipoxidation products in tissue proteins, without the necessity of invoking an increase in oxidative stress. Further, age-adjusted levels of oxidized amino acids, a more direct indicator of oxidative stress, are not increased in skin collagen in diabetes. We propose that the increased chemical modification of proteins by carbohydrates and lipids in diabetes is the result of overload on metabolic pathways involved in detoxification of reactive carbonyl species, leading to a general increase in steady-state levels of reactive carbonyl compounds formed by both oxidative and nonoxidative reactions. The increase in glycoxidation and lipoxidation of tissue proteins in diabetes may therefore be viewed as the result of increased carbonyl stress. The distinction between oxidative and carbonyl stress is discussed along with the therapeutic implications of this difference.
9884815 Clinical pharmacokinetics of oxaprozin. 1998 Dec Oxaprozin is a nonsteroidal anti-inflammatory drug which reaches peak plasma concentrations 2 to 6 hours after oral administration. Oxaprozin binds extensively, in a concentration-dependent manner, to plasma albumin. The area under the plasma concentration-time curve (AUC) of oxaprozin is linearly proportional to the dose for oral doses up to 1200 mg. At doses greater than 1200 mg there is an increase in the unbound fraction of drug, leading to an increased clearance and volume of distribution (Vd) of total oxaprozin. Accumulation of the drug at steady state is between 40 and 58% lower than predicted by single dose data. After administration of multiple doses, the apparent oral clearance (CL/F) and Vd of total oxaprozin increased while those of the unbound drug decreased significantly. Substantial concentrations of oxaprozin are attained in synovial fluid, which is a proposed site of action for nonsteroidal anti-inflammatory drugs. Relationships between total plasma, unbound plasma and synovial concentrations, and therapeutic and toxicological effects have yet to be established. Oxaprozin is eliminated following biotransformation to glucuroconjugated metabolites which are excreted in urine and bile, with little drug being eliminated unchanged. Two hydroxylated metabolites have been shown to possess anti-inflammatory activity. Hepatic disease and rheumatoid arthritis do not significantly alter the disposition of oxaprozin. Patients with renal impairment demonstrate an increase in unbound plasma concentrations of oxaprozin. A significant drug interaction has been demonstrated between oxaprozin and aspirin (acetylsalicylic acid).
9856487 The polymorphic 43Thr bcl-2 protein confers relative resistance to autoimmunity: an analyt 1998 Oct We have found a novel polymorphic (Ala43Thr; ACC-->GCC) bcl-2 allele in a Japanese population. An in vitro expression study with a mouse IL-7-dependent pre-B cell line has revealed that inhibition of the programmed cell death function of 43Thr bcl-2 protein is suppressed compared with that of normal 43Ala bcl-2 protein. Since bcl-2 expression in B-lymphoid cells elicits autoimmune disease in mice, we have investigated the possibility of whether a bcl-2 polymorphism has a different susceptibility to autoimmune disease. To evaluate the clinical impact of this polymorphism, the frequency of bcl-2 polymorphism was investigated in 221 children with insulin-dependent diabetes mellitus (IDDM), 237 adults with autoimmune disease (105 with rheumatoid arthritis, 57 with systemic lupus erythematosus, 55 with Sjögren's syndrome, and 20 others), and 290 healthy Japanese children and adults. The frequency of the 43Thr bcl-2 allele, either homozygous or heterozygous, was 14.5% in normal controls, 6.8% (P<0.01) in children with IDDM, and 8.0% (P<0.025) in adults with autoimmune disease. These results suggest that the 43Thr allele of bcl-2 confers resistance to autoimmune disease. The different anti-apoptotic function resulting from the different expression of bcl-2 protein in lymphocytes seems to be associated with the development of autoimmune disease, indicating that the bcl-2 gene affects human autoimmune disease.
9837698 D-penicillamine-induced pancreatic islet autoantibody production is independent of the imm 1998 Dec D-penicillamine (d-PA) was reported to induce various immunological abnormalities including production of autoantibodies to insulin. These abnormalities were mainly described in patients with primary immunological disorders such as rheumatoid arthritis. In order to clarify whether d-PA-induced immune disorders are restricted to patients genetically prone to develop autoimmune diseases or to a direct drug effect, we tested for the presence of various autoantibodies and for molecular HLA typing in 17 patients with Wilson's disease treated with this drug. In 2/17 patients, low-titer (10 JDFU) circulating islet cell autoantibodies (ICA) were detected, while another patient was positive for the presence of insulin autoantibodies. None of the sera tested showed reactivity for glutamic acid decarboxylase or ICA512. Five of twelve patients were positive for anti-single-stranded DNA autoantibody. Molecular HLA typing of the autoantibody-positive subjects showed that they carry HLA haplotypes not associated with insulin-dependent diabetes. The insulin response to intravenous glucose tolerance test in two patients with autoantibodies was found to be normal. A second blood testing of the autoantibody-positive patients 5 months following initial evaluation revealed conversion to negativity in all three. Our results suggest that d-PA-induced autoantibodies in patients with Wilson's disease are independent of the immunogenetic background characteristics of diabetes.
9781375 Prevalence and clinical significance of anti-lactoferrin autoantibodies in inflammatory bo 1998 Anti-neutrophil cytoplasmic antibodies (ANCA) are autoantibodies directed against cytoplasmic constituents of neutrophil granulocytes. Antibodies with specificity for proteinase 3 and myeloperoxidase are seromarkers for systemic vasculitides. ANCA with specificity for lactoferrin were described in patients with several idiopathic inflammatory diseases, such as the inflammatory bowel diseases and rheumatoid arthritis. However, the clinical significance of anti-lactoferrin autoantibodies is still unclear. In this study, we determined the clinical significance of anti-lactoferrin autoantibodies in sera from large groups of patients with ulcerative colitis (UC), Crohn's disease (CD), and primary sclerosing cholangitis (PSC). Antibodies to human lactoferrin were detected by ELISA and by immunoblotting, using an extract of sonicated neutrophils as antigen source. Autoantibodies to lactoferrin were found in 29% of patients with UC, 13% of patients with CD, and 22% of patients with PSC. In inflammatory bowel diseases, the presence of anti-lactoferrin antibodies was not related to treatment, disease activity, duration of disease, or disease extent. In PSC, the presence of autoantibodies to lactoferrin did not correlate with duration of disease or the presence of cirrhosis. However, patients with PSC and coexistent UC had significantly more frequently antibodies to lactoferrin than PSC patients without IBD. In conclusion, autoantibodies to lactoferrin are a common feature of inflammatory bowel diseases and PSC. However, the clinical significance of those autoantibodies is limited as they lack sensitivity and specificity for those disorders. Future research should address the pathophysiological role of anti-lactoferrin ANCA and the influence of anti-lactoferrin ANCA binding on the functional properties of the lactoferrin molecule.
9741302 Vitexicarpin, a flavonoid from the fruits of Vitex rotundifolia, inhibits mouse lymphocyte 1998 Aug Certain flavonoids having a C-2,3-double bond were reported to show an inhibitory activity against T-lymphocyte proliferation, but not against B-lymphocyte proliferation in vitro. In the course of these studies, vitexicarpin (3',5-dihydroxy-3,4',6,7-tetramethoxyflavone) isolated from the fruits of Vitex rotundifolia was found to show potent inhibition against lymphocyte proliferation. Vitexicarpin inhibited T-lymphocyte proliferation as well as B-lymphocyte proliferation at > 0.1 microM. IC50's were approximately 0.7 microM both for T- and B-cell proliferation. The inhibitory activity of vitexicarpin was reversible. Vitexicarpin also inhibited the growth of certain cancer cell lines, EL-4 and P815.9 (IC50 = 0.25-0.3 microM). These results suggest that vitexicarpin may be a potential therapeutic agent involved in inflammatory/immunoregulatory disorders such as rheumatoid arthritis and lymphomas.
9721563 [Two cases of polymyositis associated with interstitial pneumonia with anti-OJ (isoleucyl 1998 Jun We present two cases of polymyositis (PM) associated with interstitial pneumonia (IP) whose sera contain autoantibodies to OJ (isoleucyl tRNA synthetase). The first patient is a 51 year-old female who was diagnosed as rheumatoid arthritis (RA) and treated with gold and corticosteroid at another hospital. She was admitted to Keio University Hospital due to worsening of dyspnea on exertion and polyarthritis. Laboratory findings revealed elevation of serum CK and LDH. A diagnosis of PM was made based on the myogenic pattern of EMG and pathological feature by muscle biopsy. Chest radiography and CT showed interstitial fibrosis. Because of clinical deterioration, the dose of corticosteroid was increased (prednisolone 50 mg/day) and her symptom was stabilized. The second patient, a 62 year-old male, was admitted to Kawasaki Municipal Hospital because of dyspnea on exertion, polyarthritis, and fever. He was diagnosed as PM associated with IP on the basis of his clinical and laboratory findings, and chest radiography. He was treated with methylprednisolone pulse therapy (800 mg/day for three days) and his symptoms were improved. Both patients were found to have autoantibodies to OJ. Autoantibodies to aminoacyl tRNA synthetase have been described to be associated with myositis and/or IP. In North American, it was reported that all patients with anti-OJ had either myositis or IP or both. This suggests that anti-OJ was commonly associated with the anti-synthetase syndrome observed with other anti-synthetases. This is the first report of Japanese patients with anti-OJ antibody. The clinical features of these patients were likely to be similar to those observed in North American patients. However, further studies are necessary to clarify the precise clinical significance of this antibody.
9688041 Medical opinions, beliefs and prescription of orthopaedic footwear: a survey of Dutch orth 1998 Jun OBJECTIVES: To get insight into medical opinions about the use of orthopaedic footwear and the medical and social factors related to the prescription of orthopaedic footwear by orthopaedists and rehabilitation practitioners. METHODS: In this study 85 orthopaedists and 96 rehabilitation practitioners filled out a questionnaire measuring perceived desirability of prescribing orthopaedic footwear in specific medical conditions, the perceived advantages of orthopaedic footwear, the perceived disadvantages of orthopaedic footwear, the attitude to orthopaedic footwear and satisfaction with the co-operation with the pedorthist. Clinicians were asked to estimate their referral rate of orthopaedic footwear. RESULTS: Orthopaedists and rehabilitation practitioners agree that the prescription of orthopaedic footwear should be considered in the case of rheumatoid arthritis, amputation of the foot and diabetic foot and not be considered in the case of sprain and back pain. In the case of hallux valgi, dermatological problems and clavus (severe corn) a reticent prescription policy seems to be the optimal choice. In the other medical conditions studied no unequivocal prescription policy could be derived. Respondents who prescribed orthopaedic footwear more than the median (more than 50 prescriptions per year) were more often rehabilitation practitioner, perceived more advantages of prescription footwear, perceived less disadvantages of prescription footwear and were more satisfied about the co-operation with the pedorthist. CONCLUSION: In some medical conditions orthopaedists and rehabilitation practitioners agree about the optimal use of orthopaedic footwear. In some other medical conditions orthopaedists and rehabilitation practitioners are divided about the use of orthopaedic footwear. Reported rate of prescription was not related to desirability of prescription, but was related to beliefs such as perceived advantages, perceived disadvantages and satisfaction with co-operation with the pedorthist, underlining the importance of cognitive factors in prescription style.
9647450 Review of the effectiveness of capsaicin for painful cutaneous disorders and neural dysfun 1998 Jun BACKGROUND: Topical capsaicin is known to be a safe and effective pain management adjunct for rheumatoid arthritis, osteoarthritis, neuralgias, and diabetic neuropathy. However, studies and case reports in the literature have indicated that other conditions may also benefit from capsaicin: painful or itching cutaneous disorders from operations, injuries, or tumors; neural dysfunction; or inflammation of the airways and urinary tract. METHODS: To determine the effectiveness of capsaicin for painful cutaneous disorders and neural dysfunction, the authors analyzed data from 33 reports (MEDLINE search of 1966-96) on the efficacy of capsaicin. Outcome measures consisted of the response rate and degree of pain relief. Results from placebo-controlled trials were pooled when possible; effect of treatment was estimated by the method of DerSimonian and Laird. RESULTS: Pain relief for postmastectomy syndrome and cluster headache was greater with capsaicin than with placebo; also, psoriasis and pruritus responded better to capsaicin. Uncontrolled studies and case reports have indicated that pain or dysfunction was less at the end of capsaicin therapy for neck pain, loin pain/hematuria syndrome, oral mucositis, rhinopathy, reflex sympathetic dystrophy syndrome, detrusor hyperreflexia, and cutaneous pain due to tumor of the skin. CONCLUSIONS: Capsaicin is effective for psoriasis, pruritus, and cluster headache; it is often helpful for the itching and pain of postmastectomy pain syndrome, oral mucositis, cutaneous allergy, loin pain/hematuria syndrome, neck pain, amputation stump pain, and skin tumor; and it may be beneficial for neural dysfunction (detrusor hyperreflexia, reflex sympathetic dystrophy, and rhinopathy). A universal problem for many of the studies analyzed was the absence of a "burning placebo" such as camphor.
9459613 Interferon-beta not only inhibits interleukin-1beta and tumor necrosis factor-alpha but st 1997 Dec Imbalance between pro-inflammatory cytokines such as interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha) and their respective inhibitors is likely to be involved in the pathogenesis of chronic inflammatory disorders such as multiple sclerosis and rheumatoid arthritis. Increasing evidence suggests that the administration of interferon-beta (IFN-beta) displays some efficacy in the treatment of patients with relapsing-remitting multiple sclerosis. The aim of the present study was to determine the effect of IFN-beta on the production of pro-inflammatory cytokines and their inhibitors by stimulated peripheral blood mononuclear cells (PBMC). IFN-beta decreased the production of both IL-1beta and TNF-alpha in a dose-dependent manner, by up to 80% and 55%, respectively. Simultaneously, IFN-beta increased the production of IL-1 receptor antagonist (IL-1Ra) by 37% and did not modulate the release of TNF-soluble receptors (TNF-sRs) p55 and p75. Therefore, by favoring the production of cytokine antagonists over that of pro-inflammatory cytokines, IFN-beta induces an imbalance supporting anti-inflammatory processes. This effect might account for some of the therapeutic benefit of IFN-beta.
9437900 [Quantitative determination of serum anti ribosomal-P protein antibody by enzyme immunoass 1997 Dec An enzyme immunoassay for serum anti-ribosomal P protein antibodies (anti-P) is developed, using highly purified synthetic ribosomal P peptides of the carboxyl terminal 22 amino acid sequence conjugated to human serum albumin (HSA) as an antigen. Anti-P levels were determined by subtracting the nonspecific binding activities to HSA. The concentration of anti-P which produced half of the maximal absorbance at 492 nm (OD492) given by saturating concentrations of anti-P in the ELISA plate was defined as 1 U/ml. The anti-P values in the samples were determined by referring to a standard curve made from a standard serum containing anti-P. Serum anti-P levels in 34 normal individuals were 5.52 +/- 8.39 U/ml (mean +/- SD). Anti-P in sera from 45 patients with systemic lupus erythematosus (SLE), 24 patients with rheumatoid arthritis (RA) and 27 patients with Behçet's disease were also analyzed. The values for serum anti-P in SLE, RA and Behçet's disease groups were 251.04 +/- 843.07 U/ml, 5.97 +/- 15.18 U/ml, and 2.62 +/- 3.35 U/ml (mean +/- SD) respectively. The positive ratio for serum anti-P in SLE patients was significantly higher than that in patients with RA or Behçet's disease (p < 0.05 as determined by chi-square test). These results indicate that quantitative determination of serum anti-P by our enzyme immunoassay is a successful tool for the diagnosis of SLE.
9365111 In vivo properties of monocyte chemoattractant protein-1. 1997 Nov Monocyte chemoattractant protein-1 (MCP-1) attracts monocytes, memory T lymphocytes, and natural killer (NK) cells in vitro. Its expression has been documented in disorders characterized by mononuclear cell infiltrates, suggesting that it may contribute to the inflammatory component of such diseases as atherosclerosis, multiple sclerosis, or rheumatoid arthritis. To prove a causal association, the in vivo properties of MCP-1 must be understood. Several lines of transgenic mice have been constructed to address this question. A transgenic line in which MCP-1 expression is controlled by the MMTV-LTR expressed high levels of MCP-1 in multiple organs but showed no evidence for monocyte infiltration. Instead, these mice were more susceptible to infection by the intracellular pathogens, Listeria monocytogenes and Mycobacterium tuberculosis. These mice had high serum levels of MCP-1, suggesting that their circulating monocytes may have been desensitized or that MCP-1 stimulated a Th2-dominant response. In contrast, another model in which MCP-1 expression was controlled by the insulin promoter demonstrated a monocytic infiltrate in pancreatic islets. These results indicate that MCP-1 expression at low levels in an anatomically confined area results in monocyte infiltration, suggesting that when properly expressed, MCP-1's in vitro properties are reproduced in vivo. This justifies the examination of MCP-1-deficient mice in disease models in order to explore MCP-1's role in pathogenesis.
9333124 Fas and Fas ligand interaction is necessary for human osteoblast apoptosis. 1997 Oct We investigated the cellular and humoral interactions between peripheral blood mononuclear cells (PBMCs) and human osteoblasts, leading to apoptosis of osteoblasts. Human osteoblastic cell line MG63 and human primary osteoblast-like cells obtained from biopsy specimens were used in this study. PBMCs were isolated from healthy donors and cultured with or without stimulation by recombinant interleukin-2 followed by 12-o-tetradecanoylphorbol 13-acetate with ionomycin. Fas was functionally expressed on MG63 and primary osteoblast-like cells. Activated PBMCs expressed Fas ligand (FasL) strongly on their surface and killed MG63 and primary osteoblast-like cells. Cultured supernatants of activated PBMCs also induced apoptotic cell death of MG63 and primary osteoblast-like cells. In contrast, both unstimulated PBMCs and cultured supernatants of unstimulated PBMCs did not induce apoptosis of these cells. Furthermore, the cytotoxic effect and induction of apoptosis against MG63 and primary osteoblast-like cells by activated PBMCs and cultured supernatants were inhibited significantly by human Fas chimeric protein. Our data showed that human osteoblasts expressed Fas fuctionally and both membrane-type and soluble form FasL from activated PBMCs induced apoptosis of these cells, providing the one possible mechanism of bone loss in inflammatory diseases such as rheumatoid arthritis.
9201257 Expression of TNF-alpha by human plasma cells in chronic inflammation. 1997 Jun Tumor necrosis factor-alpha (TNF-alpha) is a potent pro-inflammatory cytokine and mediator of the inflammatory response. It has been implicated in the pathogenesis of many inflammatory disorders, including rheumatoid arthritis (RA), septic shock, and Crohn's disease. Using a specific anti-human TNF-alpha antibody we detected immunoreactivity for this cytokine in the cytoplasm of inflammatory cells in several chronic inflammatory disorders, including RA, scleritis, and polyarteritis nodosa. These cells were identified predominantly as IgG-expressing plasma cells. Lymph nodes from patients with Hodgkin's lymphoma and breast cancer, but not from control subjects, were also found to contain TNF-alpha-positive plasma cells. Cultured EBV-B lymphocytes and a human plasma cell line (ARH-77) when stimulated with phorbol myristate acetate demonstrated cytoplasmic TNF-alpha immunoreactivity. Western blot analysis of cell membranes and conditioned media from both cell types revealed the presence of the 26-kDa membrane-bound from and the 17-kDa soluble from of TNF-alpha, respectively. TNF-alpha was quantitated by enzyme-linked immunosorbent assay and found to be biologically active as determined by the L929 cytotoxicity assay. This is the first demonstration that plasma cells may be capable of modulating immune and inflammatory responses, not only by antibody production, but also by their secretion of a key inflammatory mediator, TNF-alpha.
9200922 [Binding-peptide motifs of HLA class II molecules susceptible to autoimmune diseases]. 1997 Jun Recent advances in knowledge of crystal structures of MHC class II molecules has advanced understanding of the molecular basis for interactions between peptides and HLA class II molecules. Polymorphism of HLA class II molecules influences structures of peptides bound to HLA class II molecules. To elucidate mechanisms for statistical association between particular HLA class II alleles and susceptibility to autoimmune diseases, it is important to identify self peptides presented by disease-susceptible HLA class II molecules and triggering disease-causative autoreactive T cells. In this study, we tried to identify self-peptides triggering autoimmune diseases including rheumatoid arthritis, insulin autoimmune syndrome, insulin dependent diabetes mellitus and infant-onset myasthenia gravis. Susceptibility to all of these diseases in the Japanese population are known to be strongly associated with particular HLA-DR-DQ haplotypes unique to Asians, and clinical features of some of these diseases are different between Caucasians and Asians including Japanese. We investigated differences in binding-peptide motifs between disease susceptible and non-susceptible HLA class II molecules and predicted candidates of autoimmune self-peptides carrying binding-motifs to disease-susceptible HLA class II molecules. Indeed the major epitope for insulin-autoreactive CD4+ T cell was successfully identified by this strategy. We also found heterogeneity in immunogenetic background between Western type and Asian type of multiple sclerosis. Our data indicated that our strategy is useful to identify autoimmune self-peptides, and it is suggested that not only disease-susceptible HLA class II but also self-peptides causing diseases are different between Caucasians and Asians. These differences may well correlate to different clinical manifestations of diseases between the two ethnic groups.