RESUMO
Heparin-like materials, characterized by a defined superficial density of functional groups which activate antithrombin III (AT III), when in contact with blood specifically inhibit thrombin as soon as it appears. This paper describes an isotopic method to estimate this density and to visualize the distribution of the affinity sites concerned, both directly with AT III labelled with 125Iodine and indirectly with an anti AT III monoclonal antibody labelled with 111Indium.
Assuntos
Antitrombina III , Materiais Biocompatíveis , Heparina , Adsorção , Anticorpos Monoclonais , Imunoensaio , Radioisótopos de Índio , Radioisótopos do Iodo , PoliestirenosRESUMO
Recently it has been reported that the C57BL mice can be used as a model of benign monoclonal gammopathy (MG). Since experimental models have until now failed to reproduce specific lesions of human dysglobulinemic polyneuropathies, we decided to investigate the peripheral nerve of these mice. The sciatic nerve and the serum from 14 C57BL mice were examined: 9 of these animals were found to have an IgG, kappa light chain MG, while in the other 5 no abnormalities were detected in the serum. In the 14 mice, features of demyelination were found in certain fibers, as well as onion-bulb formations around other myelinated fibers. Features of active demyelination were found in 10 animals and it must be underlined that three of these had no serum abnormalities. The decrease of the conduction velocities and the temperature coefficients Q10 of the C57BL mice suggest a good correlation between morphological and functional parameters. This strongly suggests that this strain of mice provides a suitable model for inflammatory demyelinating polyneuropathy (IDPN).
Assuntos
Doenças Desmielinizantes/fisiopatologia , Modelos Animais de Doenças , Paraproteinemias/fisiopatologia , Nervo Isquiático/fisiopatologia , Animais , Doenças Desmielinizantes/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Gamopatia Monoclonal de Significância Indeterminada/patologia , Gamopatia Monoclonal de Significância Indeterminada/fisiopatologia , Condução Nervosa , Paraproteinemias/patologia , Nervo Isquiático/ultraestruturaRESUMO
OBJECTIVE: To determine the prevalence of organ-specific and non-specific autoantibodies in HIV-infected patients. DESIGN: A multicentric collaborative case-control study including 105 HIV patients and 100 sex- and age-matched HIV-negative healthy volunteers. METHODS: Antinuclear, anti-ds DNA, anti-histone, anti-Sm, rheumatoid factor(IgM), anti-beta 2 glycoprotein 1, antineutrophil cytoplasmic, anti-LKM1, anti-LCA1, anti-gastric parietal cell, antiplatelet, anti-intermediate filament, anti-mitotic spindle apparatus, anti-Golgi, anti-ribosome and anti-thyroid autoantibodies were screened in six European laboratories. RESULTS: Only IgG and IgM anticardiolipin, IgG antiplatelet, anti-smooth muscle and anti-thyroglobulin antibodies were statistically more frequent in HIV patients. There was no correlation with the numbers of CD4+ cells except in the case of anti-smooth muscle antibodies. We were unable to find specific autoantibodies such as anti-ds DNA, anti-Sm, AMA, anti-LKM1, anti-LCA1 or anti-beta 2 GP1 antibodies in these patients. CONCLUSIONS: Our results indicate that the autoantibody profile of HIV infections is comparable to those of other chronic viral infections. HIV does not seem to be more autoimmunogenic than other viruses.
Assuntos
Autoanticorpos/imunologia , Infecções por HIV/imunologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
We report the case of a woman who, at the age of 27, developed a cerebral arterial occlusion. The laboratory investigations showed an anti-human beta2-glycoprotein I antibody, but no other biological sign of antiphospholipid antibody syndrome or autoimmune disorders. The patient otherwise presented with diabetes and moderate obesity. The species specificity of anti-beta2-glycoprotein I antibodies probably explains the discrepancy between false negative results for antiphospholipid antibodies assayed by clotting and ELISA studies and positivity for anti-human beta2-glycoprotein I. Further studies will be important to evaluate the frequency of such antibodies, as well as their value as a risk factor for venous and arterial thrombosis, and their signification within the antiphospholipid antibody syndrome.
Assuntos
Autoanticorpos/sangue , Infarto Cerebral/imunologia , Glicoproteínas/imunologia , Embolia e Trombose Intracraniana/imunologia , Adulto , Infarto Cerebral/complicações , Complicações do Diabetes , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Embolia e Trombose Intracraniana/complicações , beta 2-Glicoproteína IRESUMO
PURPOSE: Autoantibodies directed against the ribosomal P proteins, P0, P1 and P2 (anti-P), have been related to lupus-related psychosis and/or depression. The diagnostic value of antibodies directed against other ribosomal proteins or 28S RNA (anti-no-P) remains unknown. A multicenter study including ten centers belonging to the study group for autoimmune diseases (GEAI) was conducted in order to determine the diagnostic value of anti-P and anti-no-P antibodies in a large population of patients. METHODS: The patients were selected on the basis of the presence of serum anti-ribosomal antibodies detected by indirect immunofluorescence (IF) on rat liver/kidney/stomach/pancreas sections and human HEp2 cells. The clinical course of all patients was studied using a predetermined survey. The specificity of anti-P antibodies were determined by Western blot. RESULTS: Anti-ribosomal antibodies were found in 82 patients. Fifty-five of them had systemic lupus erythematosus and 27 had another disease. Only 54% of the anti-ribosomal antibodies detected by IF were anti-P and were found in 69% of the patients with systemic lupus erythematosus. Anti-no-P antibodies (46%) were preferably detected in patients who suffered from another disease (78%). In patients with systemic lupus erythematosus, neurological and psychiatric disorders were more frequent in the no-P group (47% vs. 16%, P < 0.01) than arthritis, which was found more frequently in the P group (78% vs. 53%, P < 0.05). CONCLUSION: Anti P antibodies do not constitute a specific diagnostic marker of systemic lupus erythematosus, and lupus-related neuropsychiatric disorders would be preferably associated with the presence of anti no-P antibodies.
Assuntos
Autoanticorpos/análise , Transtorno Depressivo/diagnóstico , Lúpus Eritematoso Sistêmico/diagnóstico , Transtornos Psicóticos/diagnóstico , Proteínas Ribossômicas/imunologia , Animais , Biomarcadores/análise , Western Blotting , Transtorno Depressivo/etiologia , Humanos , Lúpus Eritematoso Sistêmico/psicologia , Estudos Prospectivos , Transtornos Psicóticos/etiologia , RatosAssuntos
Imunoglobulina M/análise , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Feminino , Humanos , MasculinoRESUMO
Activation of the complement system in vitro by a series of microcapsules based on polylysine, alginate or polyacrylamide was determined. Least activation was observed with microcapsules whose outer layer was composed of polyacrylamide. Activation was further reduced using diacrylylpiperazine instead of bisacrylamide as crosslinker.
Assuntos
Acrilamidas/farmacologia , Resinas Acrílicas/farmacologia , Ativação do Complemento/efeitos dos fármacos , Reagentes de Ligações Cruzadas , Cápsulas , Complemento C3 , Complemento C3c , Complemento C4 , Teste de Materiais , Piperazinas , Zimosan/farmacologiaRESUMO
Microencapsulated islets of Langerhans retrieved from peritoneal cavity of rats three weeks after implantation had a reduced hormonal secretion and were no longer responsive to alterations in glucose levels. Activation of complement could not completely account for the observed fibrosis which was thought to be responsible for the loss of responsiveness of the encapsulated cells.
Assuntos
Ativação do Complemento/fisiologia , Glucose/farmacologia , Ilhotas Pancreáticas/metabolismo , Microesferas , Próteses e Implantes , Animais , Inflamação/fisiopatologia , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Transplante das Ilhotas Pancreáticas , RatosRESUMO
Quantitative, immunopathological, light and electron microscopic studies of superficial peroneal nerve biopsies from 31 patients with IgM monoclonal gammopathy were carried out. Six patients had Waldenström's macroglobulinemia and 25 had IgM monoclonal gammopathy of undetermined significance. Serum samples from 28 of these patients were assayed for anti-myelin-associated glycoprotein (anti-MAG) activity. Anti-MAG activity was found in 25 of the samples. There was a relationship between the widening of some myelin lamellae observed on ultrastructural examination and the serum anti-MAG activity (23 cases). Immunopathological examination showed IgM binding to myelin sheaths in 17 cases.
Assuntos
Autoanticorpos/imunologia , Cadeias mu de Imunoglobulina/metabolismo , Proteínas da Mielina/imunologia , Paraproteinemias/complicações , Doenças do Sistema Nervoso Periférico/etiologia , Idoso , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Glicoproteína Associada a Mielina , Doenças do Sistema Nervoso Periférico/imunologia , Doenças do Sistema Nervoso Periférico/patologiaRESUMO
In a patient with Waldenström's macroglobulinaemia and peripheral neuropathy, direct immunofluorescence of a peripheral nerve revealed the presence of abundant IgM and kappa light chain deposits in the endoneurium. Electron microscopic examination showed the microtubular structure of these endoneurial deposits, which strongly suggested the presence of cryoglobulin; this was then found in the serum.
Assuntos
Crioglobulinas/metabolismo , Imunoglobulina M/metabolismo , Nervos Periféricos/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Macroglobulinemia de Waldenstrom/complicações , Idoso , Idoso de 80 Anos ou mais , Imunofluorescência , Humanos , Cadeias kappa de Imunoglobulina/metabolismo , Masculino , Microscopia Eletrônica , Nervos Periféricos/patologia , Doenças do Sistema Nervoso Periférico/complicações , Doenças do Sistema Nervoso Periférico/patologiaRESUMO
A 59-year-old woman with a history of papillary carcinoma of the thyroid gland developed three reddish nodules on the scalp. A skin biopsy showed a dermal tumor composed of sheets of clearly differentiated thyroid vesicles. Cutaneous metastases of thyroid carcinoma are very rare and this case is the first case confirmed by immunoperoxidase studies using monoclonal antithyroglobulin antibody. Positive reactions were obtained in colloid and at apices of thyrocytes. Monoclonal antibodies to human thyroglobulin may offer a unique opportunity to confirm the tissue origin of cutaneous metastasis.
Assuntos
Anticorpos Monoclonais , Carcinoma Papilar/secundário , Neoplasias Cutâneas/secundário , Tireoglobulina/imunologia , Neoplasias da Glândula Tireoide , Tretinoína/análogos & derivados , Acitretina , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Tretinoína/administração & dosagem , Tretinoína/sangue , Tretinoína/farmacocinéticaRESUMO
Five different nanoparticles, potentially useful in magnetic resonance imaging (MRI) after venous administration, were studied for their hemocompatibility. The in vitro methodology evaluated these materials by several parameters: cytotoxicity towards cells cultured in vitro, aggregation ability of platelets, hemolysis inducibility, intrinsic and extrinsic coagulation pathway activation, and complement activation. With the proposed clinical dose, regardless of the cell type used (murine cell line or human endothelial cells) no toxicity was observed. The presence of the particles in blood did not produce any considerable damage: either hemolysis or platelet aggregation or blood coagulation were recorded. However, a slight decrease in aggregation ability of platelets was noticed as well as an increase in partial thromboplastin time. Because of the quick removal of the particles from the bloodstream, these phenomena must be short-lived, thus avoiding significant adverse clinical effects.
Assuntos
Meios de Contraste , Complexo Ferro-Dextran , Imageamento por Ressonância Magnética , Animais , Coagulação Sanguínea , Bovinos , Ativação do Complemento , Meios de Contraste/química , Meios de Contraste/toxicidade , Citotoxicidade Imunológica , Hemólise , Histocompatibilidade , Complexo Ferro-Dextran/toxicidade , Teste de Materiais , Camundongos , Tamanho da Partícula , Agregação PlaquetáriaRESUMO
Hemodialysis with complement-activating membranes, such as cuprophane, induces neutropenia and expression of the granulocyte adhesion receptor Mac-1 (CD11b/CD18), while hemodialysis with noncomplement-activating membranes does not. Increased expression of CD11b by neutrophils may mediate cuprophane-induced leukopenia. However, the rebound granulocytosis that follows leukopenia is not fully understood. Ten patients on regular hemodialysis were included in a cross-over study. Hemodialysis was performed for 2 weeks with cuprophane and 2 weeks with polyamide, a high-flux noncomplement-activating membrane. At the end of each period, the following parameters were determined during a hemodialysis session: C5a concentration by enzyme immunoassay and the neutrophil expression of CD11b, LFA-1 (CD11a/CD18), and the antigen recognized by MoF11 (MoF11 Ag), a monoclonal antibody that recognizes activated neutrophils, by immunofluorescence flow cytometry. Hemodialysis with cuprophane induced an increase in C5a concentration and in the expression of CD11b and MoF11 Ag, which were maximal after 15 minutes of hemodialysis, at the nadir of neutropenia. CD11b expression was maintained throughout hemodialysis, despite the reversal of neutropenia. Conversely, after peak expression, C5a and MoF11 Ag decreased as the neutrophil count increased to baseline values. Polyamide hemodialysis did not induce variations in C5a concentration, nor in CD11b and MoF11 Ag expression. CD11a/CD18 expression remained stable during hemodialysis with both membrane types. Neutrophil activation, as determined by MoF11 Ag expression, was correlated with the evolution of neutrophil count and C5a concentration during cuprophane hemodialysis, while CD11b expression was not correlated with neutrophil count throughout dialysis. A decrease in neutrophil activation could explain in part the detachment of neutrophils previously bound to endothelium and, therefore, the reversal of neutropenia.(ABSTRACT TRUNCATED AT 250 WORDS)