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Biomedical subjects

M Meurer

Publications and source records attributed to M Meurer.

At least 55 records · Page 3Linked to original sources

Strain-dependent cytokine profile and susceptibility to oleic acid anilide in a murine model of the toxic oil syndrome.

The toxic oil syndrome (TOS) was caused by the ingestion of an adulterated rapeseed oil containing oleic acid anilide (OAA). It was characterized by lethal symptoms in the acute phase and by symptoms of idiopathic autoimmune diseases in the chronic phase. The pathogenetic mechanisms remain unclear. In a murine model of TOS we demonstrate strain-dependent effects on the immune system after treatment with OAA intraperitoneally. While C57BL/6 (H-2b) mice develop a polyclonal B cell activation without disease symptoms, most A/J (H-2a) mice suffer an acute lethal wasting disease. These differences are reflected in the splenic cytokine gene expression and secretion and in the Ig production. Increased IgE serum levels and reduced TNF-beta mRNA suggest a Th2 cell response in C57BL/6 mice. In A/J mice, splenocytes express IL-1alpha, IL-10, and IFN-gamma mRNA in vivo and secrete high levels of TNF-alpha in vitro. These observations resemble the human condition in TOS with development of either an acute lethal disease or a chronic autoimmune-like disease. As in other chemical-induced reactions genetic susceptibility seems to be important.

Anilides↗

Human keratinocyte line HaCaT metabolizes 1alpha-hydroxyvitamin D3 and vitamin D3 to 1alpha,25-dihydroxyvitamin D3 (calcitriol).

Cultured human keratinocytes have the property to hydroxylate exogenous 25-hydroxyvitamin D3 (25OHD3) at the C-1alpha position thus producing 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3). In this study we investigated whether keratinocytes can also hydroxylate vitamin D3 and one of its metabolites at the C-25 position. We could demonstrate that HaCaT keratinocytes can metabolize 1alpha-hydroxyvitamin D3 (1alpha-OHD3) and vitamin D3 to 1alpha,25(OH)2D3. Identification of the generated product as 1alpha,25(OH)2D3 was based on its elution pattern in two different high performance liquid chromatography systems, on its specific binding in a calf thymus receptor assay and on its gas chromatography-mass spectrometry characteristics. The hydroxylation of vitamin D3 to 1alpha,25(OH)2D3 was dose- and time-dependent. Bovine serum albumin added up to 1.5% (w/v) to the culture medium greatly increased the hydroxylation rates. These results show that HaCaT cells have the capacity to hydroxylate vitamin D3 at the C-1/25 positions. The generation of endogenous 1alpha,25(OH)2D3 from vitamin D3 within the skin may indicate a novel pathway which is of importance for the regulation of epidermal cell growth and differentiation.

Animals↗

Autoantibodies to C-reactive protein (CRP) and other acute-phase proteins in systemic autoimmune diseases.

Autoantibodies to CRP were reported previously in patients suffering from toxic oil syndrome. This syndrome resembles autoimmune diseases such as systemic lupus erythematosus (SLE) or systemic scleroderma. We therefore examined the prevalence of antibodies to CRP and other acute-phase proteins in autoimmune diseases, including SLE, subacute cutaneous lupus erythematosus (SCLE), systemic scleroderma (SSc), and primary biliary cirrhosis (PBC), as well as in bone marrow transplantation-induced chronic graft-versus-host disease and eosinophilia-myalgia syndrome. IgG antibodies to CRP were found in 78% of SLE and in 30% of SCLE patients, while 16% of patients with PBC were positive. In up to 45% of patients with SSc predominantly IgG antibodies to ceruloplasmin were detectable. Lack of systemic involvement as in discoid lupus erythematosus and localized scleroderma (morphea) correlated with low or absent antibody formation. However, no correlation was found between anti-acute-phase protein antibodies with liver disease or other organ involvement. Adsorption studies revealed that non-native epitopes on the CRP molecule, termed modified CRP, are the main target of antibodies. Chronic inflammatory tissue injury in systemic autoimmune disease might increase the presentation of cryptic epitopes of CRP to the threshold required for T cell activation.

Acute-Phase Proteins↗

[Generalized Mycobacterium avium-intracellulare infection due to immunosuppressive therapy of paraneoplastic dermatomyositis].

The ubiquitous Mycobacterium avium-intracellulare (MAI) is the most frequent cause of disseminated atypical mycobacteriosis in AIDS patients. MAI infections may develop in patients with other acquired immune defects, such as connective tissue disorders. In adults, the gastrointestinal and respiratory systems are most frequently affected. We report a patient with dermatomyositis receiving immunosuppressive therapy in whom only the skin and the skeletal system were affected by MAI. Because it presented with polymyositis-like symptoms, the infection was initially not identified and treated. The MAI was cultured from a periarticular joint effusion from the right upper arm and from venous blood, as well as identified histologically in lesional skin. Resistance to antibiotics developed most likely because the patient failed to take oral antibiotics regularly. Because of an acute exacerbation of the tumor-associated dermatomyositis, immunosuppressive therapy was initiated, while the tuberculostatic therapy was continued. Using these therapies both diseases markedly improved. In patients with connective tissue disorders receiving longterm immunosuppressive therapy, especially when changes in symptoms and signs are observed, opportunistic infections such as MAI should be considered and included in the differential diagnosis.

Adenocarcinoma↗

[Brazilian pemphigus foliaceus (fogo selvagem)].

Most of the clinical, histological and immunohistological features of fogo selvagem resemble those of idiopathic pemphigus foliaceus (PF). Both diseases are clinically characterized by small flaccid bullae evolving into to scaly and crusted lesions, sometimes with pustules, mainly in seborrheic areas of the skin. Mucosal surfaces are mostly spared. The main histologic feature of endemic pemphigus foliaceus is a subcorneal acantholytic blister. Standard immunofluorescence studies demonstrate intercellular IgG deposits throughout the entire epidermis. These IgG antibodies are mainly of the IgG4-subclass. Almost all patients have circulating IgG-autoantibodies in their serum directed against stratified epithelial desmosomes. The fogo selvagem autoantibodies and the PF antibodies are directed against the 160 kD desmosomal glycoprotein desmoglein 1 which together with plakoglobin (85 kD) forms a complex of adhesion proteins with desmosomes of stratified epithelia. Fogo selvagem occurs in endemic foci in some areas of Brazil and possibly in neighbouring South American countries, very often in children, adolescents and young adults. The etiology of fogo selvagem is still unknown. The frequent association with insect bites has lead to the concept of fogo selvagem being a transmissible disease with acquired immunity in adulthood. However, the infectious agent and possible vectors have not yet been identified.

Adolescent↗

Chronic ulcerative stomatitis.

Chronic ulcerative stomatitis (CUS) has recently been described as a new disease entity characterized by chronic ulceration of oral mucosa which responds to treatment with hydroxychloroquine. It has a particular type of stratified epithelium-specific, antinuclear autoantibody as an immunological marker. Twelve cases have been reported in the literature. We present a 40-year-old woman with an 11-year history of chronic oral ulcerations. Other dermatological diseases, including oral lichen planus, pemphigus vulgaris and cicatricial pemphigoid, as well as bullous lupus erythematosus, were excluded. The clinical diagnosis of CUS was confirmed on the grounds of the immunological and ultrastructural findings. The lesions initially responded to high doses of systemic corticosteroids but relapsed promptly after dose reduction. Dapsone was ineffective. Hydroxychloroquine, given at a dosage of 200-400 mg/day, led to a complete and long-lasting remission.

Adult↗

[Effects of various prokinetic drugs on gastrointestinal transit times in patients with progressive systemic scleroderma].

The intestine is involved in about half of the cases with progressive-systemic sclerosis. Intestinal transit disturbances which are caused by neuropathy of the enteric nerve system occur frequently. However, upto-date only few studies which determined the effect of prokinetic drugs exist. Patients with intestinal involvement caused by progressive-systemic sclerosis were treated with the prokinetic drugs cisapride (20 mg, TID; n = 9), erythromycin (250 mg, TID; n = 7) and octreotide (50 micrograms s. c., at night time; n = 5) over a period of four weeks. At study entry and after each treatment period the transit times through the stomach, small and large intestine were evaluated by use of the metal-detector test. Gastric emptying was only accelerated by erythromycin (42 +/- 3 min vs. 54 +/- 6 min; p = 0.0422), whereas treatment with cisapride and octreotide did not result in significant changes (48 +/- 4 min; p = 0.3743 and 44 +/- 4 min; p = 0.1975; resp.). Small intestinal transit times were not altered significantly by cisapride (108 +/- 15 min vs. 108 +/- 9 min; p = 0.2733), crythromycin (92 +/- 8 min; p = 0.0707) or octreotide (106 +/- 12 min; p = 0.8927). Furthermore colonic transit was not fastened by none of the prokinetic agents (study entry: 68 +/- 12 h; cisapride: 88 +/- 12 h; p = 0.0569; erythromycin 77 +/- 14 h; p = 0.7349; octreotide 107 +/- 14 h; p = 0.8927). Four patients were withdrawn from the study because of diarrhea. Prokinetic drugs do not seem to have a major impact on intestinal transit times in patients with progressive-systemic sclerosis. The use of these drugs is limited because of frequent side effects.

Aged↗

Generalized atrophic benign epidermolysis bullosa. Either 180-kd bullous pemphigoid antigen or laminin-5 deficiency.

BACKGROUND: Generalized atrophic benign epidermolysis bullosa (GABEB) is a form of nonlethal junctional epidermolysis bullosa, clinically characterized by generalized blistering after birth, atrophic healing, and incomplete universal atrophic alopecia with onset in childhood. Recently, we discovered a deficiency of the 180-kd bullous pemphigoid antigen (BP180) and a reduced amount of BP180 messenger RNA in three patients with GABEB. It is not yet clear, however, whether GABEB is invariably caused by BP180 deficiency. RESULTS: We examined 18 patients with nonlethal junctional epidermolysis bullosa from unrelated families; nine of these individuals presented with the clinical characteristics of GABEB. Specimens of clinically normal skin obtained from the patients were stained by immunofluorescence with monoclonal antibodies to BP180 and laminin-5. The BP180 epitopes were not expressed in eight patients, all of whom were sharing the typical clinical features of GABEB. In one of the nine patients with GABEB, the BP180 level was sufficient, but the laminin-5 level was reduced. Among the nine patients with junctional epidermolysis bullosa without atrophic alopecia, laminin-5 level was not expressed in one patient, while in the other patients both antigens were normally expressed. CONCLUSIONS: Not all patients with GABEB are deficient in BP180, since some individuals with GABEB only exhibit reduction of the laminin-5 expression. The BP180 deficiency in the skin invariably seems to result in GABEB. Immunofluorescence analysis using monoclonal antibodies against BP180 (and laminin-5) may allow early subtyping, which is of prognostic significance, in children born with junctional epidermolysis bullosa.

Adolescent↗

Novel autoantibodies against muscle-cell membrane proteins in patients with myositis.

OBJECTIVE: To search for autoantibodies against muscle cell-specific surface membrane antigens in patients with inflammatory myopathies. METHODS: A cell enzyme-linked immunosorbent assay (cell ELISA) using a human rhabdomyosarcoma cell line (TE-671) was developed and performed in serial dilutions with either nonfixed or fixed cells. A total of 141 different patient sera were tested: 90 from patients with various rheumatic diseases, 12 from patients with cardiomyopathies, 25 from patients with other muscular diseases, and 14 from patients who had undergone major surgery or who had other noninflammatory diseases. As controls, 20 sera were obtained from healthy donors. Results were correlated using immunofluorescence staining and flow cytometry. RESULTS: Using the nonfixed cell ELISA, the proportions of positive sera from the patient groups with rheumatic diseases were 71% with polymyositis (PM), 15% with dermatomyositis (DM), 18% with systemic sclerosis (SSc), 15% with systemic lupus erythematosus (SLE), and 7% with rheumatoid arthritis. Sera from healthy donors, as well as sera from patients with nonrheumatic diseases, did not show significant reactivities. When other cell lines, including a chondrosarcoma, a bladder carcinoma, a pancreas carcinoma, and human foreskin fibroblasts, were used as substrates, positive sera did not react in the cell ELISA. Results obtained with the cell ELISA system using nonfixed cells were confirmed by flow cytometry and immunofluorescence staining. A strong protein band of 50 kd was detected on plasma membrane preparations from TE-671 muscle cells in 33% of PM sera (n = 12). CONCLUSION: In most sera from patients with PM, DM, and some other rheumatic diseases (i.e., SSc and SLE), autoantibodies directed against muscle-cell surface antigens can be detected. Since these molecules are localized in the muscle-cell surface membrane, autoantibodies directed against these antigens could play a major role in the pathogenesis of PM.

Adult↗

Treatment of severe cutaneous lupus erythematosus with a chimeric CD4 monoclonal antibody, cM-T412.

BACKGROUND: Monoclonal CD4 antibodies are among the most potent immunomodulatory agents in various experimental models of autoimmune disease, including murine lupus erythematosus. OBJECTIVE: The aim of this study was to evaluate the toxicity and therapeutic efficacy of a chimeric monoclonal CD4 antibody, cM-T412, in patients with cutaneous lupus erythematosus (LE). METHODS: Five patients with severe cutaneous LE lesions received intravenously a total of 275, 400, or 475 mg of cM-T412 in single doses of 20 to 50 mg during a period of 5 to 8 weeks. RESULTS: CD4 antibody treatment induced a long-lasting decrease in disease activity. It resulted in healing of LE skin lesions, a reconstituted responsiveness to conventional treatment, or both. Despite a substantial depletion of circulating CD4+ T lymphocytes, no clinical signs of immunosuppression were noted. CONCLUSION: Monoclonal CD4 antibodies should be considered as a novel treatment for the management of severe cutaneous LE.

Adjuvants, Immunologic↗

Orificial tuberculosis: detection by polymerase chain reaction.

Orificial tuberculosis (OT) is a rare manifestation of cutaneous tuberculosis in immunocompromised individuals. Due to its variable clinical features, the diagnosis may be missed at the onset of the disease. We report a 53-year-old patient who had OT and miliary spread of Mycobacterium tuberculosis to the lungs, liver, bones and skin. The diagnosis was established by polymerase chain reaction (PCR) amplification of a Mycobacterium-specific gene segment, and confirmed by culture. PCR allows the detection of mycobacterial DNA within a few days, whereas culture takes many weeks. PCR may improve the accurate diagnosis of skin tuberculosis and allow early treatment.

Base Sequence↗

Bronchoalveolar lavage for evaluation and management of scleroderma disease of the lung.

Fibrosing alveolitis (FA) is a frequent and often fatal complication of systemic sclerosis (SSC). Alveolar inflammation has been recognized as a primary event in the pulmonary manifestation of SSC. To evaluate the significance of the alveolitis in SSC, we performed bronchoalveolar lavage (BAL) and correlated the generated data with changes in lung function over time. Seventy nine SSC patients with pulmonary involvement were followed for 56.8 +/- 3.1 wk (mean +/- SEM) with a repeat lung function test at the end of the follow-up period. During follow-up, 38 patients were treated with a systemic immunosuppressive regimen. For evaluation, patients were assigned to two groups according to whether their BAL cell differential was normal (inactive BAL) or abnormal (active BAL: i.e., polymorphonuclear leukocytes > 5% and/or lymphocytes > 15%). Active BAL was associated with more severe lung function impairment than was inactive BAL, and patients with active BAL deteriorated during follow-up if untreated. In contrast, treated patients with active BAL stabilized or improved. In summary, active alveolitis as characterized by BAL is associated with progressive pulmonary disease in SSC patients, and a significant positive effect of immunosuppressive therapy on the course of pulmonary disease was observed in patients with active BAL.

Bronchoalveolar Lavage↗

Specificity of antinuclear antibodies in scleroderma-like chronic graft-versus-host disease: clinical correlation and histocompatibility locus antigen association.

Chronic graft-versus-host disease after bone marrow transplantation presents, in a few cases, as mild to severe scleroderma-like changes. Patients with chronic graft-versus-host disease with and without sclerodermatous skin changes were analysed for antinuclear autoantibodies (ANA) and antinucleolar autoantibodies (ANoA) and the results correlated with disease symptoms and histocompatibility locus antigen (HLA) pattern. Nineteen patients with chronic graft-versus-host disease and scleroderma-like skin changes, 18 with chronic graft-versus-host disease without scleroderma, and 17 controls on immunosuppressive treatment were screened for ANA and ANoA using enzyme-linked immunosorbent assay, immunodiffusion and immunoblot techniques. Four patients with severe scleroderma had antibodies to topoisomerase I, two had antibodies against PM-Scl, both characteristic serological findings in idiopathic systemic scleroderma. One patient had La/SSB antibodies and, in three cases, antibodies to the nucleolar antigen C23 (nucleolin) could be identified. A possible correlation between antinucleolin antibodies and disease activity was observed. HLA-A1, -B1, and -B2 were found significantly more often in patients with scleroderma-like symptoms in comparison to patients without scleroderma-like symptoms. Chronic graft-versus-host disease with scleroderma-like manifestations can be associated with the occurrence of ANA specific for idiopathic scleroderma. The development of scleroderma after bone marrow transplantation might have a HLA-linked genetic background.

Antibodies, Antinuclear↗

[Skin ulcers in rheumatoid arthritis].

The appearance of severe ulceration of the skin in patients with rheumatoid arthritis is often associated with a tendency to progression of the underlying disease, involvement of internal organs and increased mortality. In the pathogenesis of such ulceration there are multiple causes for their development, persistence and tendency to poor healing. They include localized or generalized immune complex vasculitis, treatment with anti-inflammatory drugs and their side effects following the treatment, arterial and venous insufficiency, and mechanical factors. The management of severe ulceration requires stabilization of the underlying autoimmune disease, e.g. with high doses of glucocorticosteroids or other immunosuppressive drugs or plasmapheresis. Adjuvant treatment of pain with analgesics, improvement of blood perfusion and anti-inflammatory drugs should accompany the topical therapy of ulcers. After suppression of the local inflammatory reaction surgical intervention becomes necessary in most of the patients, and vascularized muscle flaps should be used in preference to meshgrafts or split skin grafts for extensive ulceration in rheumatoid arthritis. A hopeful perspective in the treatment of severe rheumatoid arthritis might be opened up with immunotherapy using monoclonal antibodies.

Aged↗

[Pachydermoperiostosis].

Pachydermoperiostosis (Friedreich-Erb-Arnold syndrome, Touraine-Solente-Golé syndrome) is a rare disease with an autosomal dominant mode of inheritance; it occurs almost exclusively in men. A report of typical pachydermoperiostosis in a 31-year-old man is presented. Associated features were clubbed digits of the hands and feet with watch-crystal nails, thickening of the skin and soft tissues, hyperhidrosis of hands and feet, hyperplasia of the sebaceous glands with seborrhoea, gynaecomastia, and ophthalmic abnormalities that had been present since puberty. Radiological examination revealed periosteal hyperostosis of the short and long bones. Endocrine disturbances were not detected. Skin biopsies showed hypertrophy of the skin and skin appendages. Primary (idiopathic, hereditary) pachydermoperiostosis should be distinguished from secondary (symptomatic) forms of the disease, which are often associated with lung tumours.

Adult↗

No evidence for Borrelia burgdorferi-specific DNA in lesions of localized scleroderma.

A possible association of Borrelia burgdorferi with localized scleroderma is currently the focus of intense research and discussion. Skin biopsies from 30 patients with localized scleroderma (28 of the plaque type/morphea; two linear scleroderma) were analyzed for the presence of Borrelia burgdorferi using three different polymerase chain reaction systems for amplification of segments of borrelial genes. Formalin-fixed, paraffin-embedded biopsies of 14 patients and fresh-frozen, cryo-conserved biopsies of 16 patients with localized scleroderma were obtained. Lesions of all patients showed clear signs of scleroderma and disease progression at the time of biopsy. Fresh-frozen as well as formalin-fixed biopsies from patients with erythema migrans or acrodermatitis chronica atrophicans were used as positive controls. With all three polymerase chain reaction systems, borrelial DNA was detected in none of the 30 specimens of localized scleroderma. In contrast, with one polymerase chain reaction system, Borrelia burgdorferi-specific DNA was found in 24 of 27 frozen biopsies from patients with erythema migrans and in all 5 analyzed frozen biopsies of patients with acrodermatitis chronica atrophicans. In approximately half of the paraffin-embedded biopsies from patients with erythema migrans (nine of 23) and acrodermatitis chronica atrophicans (13 of 27), Borrelia burgdorferi-specific DNA was identified. These results question the association of localized scleroderma with known subtypes of Borrelia burgdorferi.

Acrodermatitis↗