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3.
Clin Exp Immunol ; 177(2): 544-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749847

RESUMO

Hereditary angioedema (HAE) is characterized by potentially life-threatening recurrent episodes of oedema. The open-label extension (OLE) phase of the For Angioedema Subcutaneous Treatment (FAST)-1 trial (NCT00097695) evaluated the efficacy and safety of repeated icatibant exposure in adults with multiple HAE attacks. Following completion of the randomized, controlled phase, patients could receive open-label icatibant (30 mg subcutaneously) for subsequent attacks. The primary end-point was time to onset of primary symptom relief, as assessed by visual analogue scale (VAS). Descriptive statistics were reported for cutaneous/abdominal attacks 1-10 treated in the OLE phase and individual laryngeal attacks. Post-hoc analyses were conducted in patients with ≥ 5 attacks across the controlled and OLE phases. Safety was evaluated throughout. During the OLE phase, 72 patients received icatibant for 340 attacks. For cutaneous/abdominal attacks 1-10, the median time to onset of primary symptom relief was 1·0-2·0 h. For laryngeal attacks 1-12, patient-assessed median time to initial symptom improvement was 0·3-1·2 h. Post-hoc analyses showed the time to onset of symptom relief based on composite VAS was consistent across repeated treatments with icatibant. One injection of icatibant was sufficient to treat 88·2% of attacks; rescue medication was required in 5·3% of attacks. No icatibant-related serious adverse events were reported. Icatibant provided consistent efficacy and was well tolerated for repeated treatment of HAE attacks.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Bradicinina/análogos & derivados , Adulto , Angioedemas Hereditários/diagnóstico , Bradicinina/administração & dosagem , Bradicinina/efeitos adversos , Bradicinina/uso terapêutico , Antagonistas dos Receptores da Bradicinina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retratamento , Resultado do Tratamento , Adulto Jovem
4.
Allergy ; 69(3): 305-14, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24438203

RESUMO

BACKGROUND: Historically, treatment for hereditary angioedema (HAE) attacks has been administered by healthcare professionals (HCPs). Patient self-administration could reduce delays between symptom onset and treatment, and attack burden. The primary objective was to assess the safety of self-administered icatibant in patients with HAE type I or II. Secondary objectives included patient convenience and clinical efficacy of self-administration. METHODS: In this phase IIIb, open-label, multicenter study, adult patients were trained to self-administer a single 30-mg icatibant subcutaneous injection to treat their next attack. Icatibant-naïve patients were treated by an HCP prior to self-administration. Evaluations included adverse event (AE) reporting, a validated questionnaire for convenience, and visual analog scale for efficacy. RESULTS: A total of 151 patients were enrolled; 104 had an attack requiring treatment during the study, and 97 patients (19 naïve) were included in the self-administration cohort. Recurrence or worsening of HAE symptoms (22 of 97) was the most commonly reported AE; rescue medications including icatibant (N = 3) and C1-inhibitor concentrate (N = 6) were used in 13 cases. Overall, 89 of 97 patients used a single injection of icatibant. No serious AEs or hospitalizations were reported. Most patients (91.7%) found self-administration preferable to administration in the clinic. The median time to symptom relief (3.8 h) was comparable with results from controlled trials of icatibant. CONCLUSIONS: With appropriate training, patients were successfully able to recognize HAE attacks and decide when to self-administer icatibant. This, coupled with the patient-reported high degree of satisfaction, convenience and ease of use supports the adoption of icatibant self-administration in clinical practice.


Assuntos
Angioedemas Hereditários/tratamento farmacológico , Bradicinina/análogos & derivados , Adulto , Bradicinina/administração & dosagem , Bradicinina/efeitos adversos , Bradicinina/uso terapêutico , Antagonistas dos Receptores da Bradicinina , Progressão da Doença , Feminino , Angioedema Hereditário Tipos I e II/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Recidiva , Fatores de Risco , Autoadministração , Resultado do Tratamento
6.
Allergol Immunopathol (Madr) ; 36(3): 182-3, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18680708

RESUMO

Hereditary angioedema is a rare autosomal dominant disease characterized by recurrent episodes of acute edema affecting the skin and the respiratory and digestive tracts. Acute edema blisters or hydro-static bullae develop after rapid accumulation of interstitial fluid usually associated to cardiac insufficiency. Lesions contain sterile fluid and break up easily resolving without scars. Blisters disappear when fluid accumulation resolves. We describe a patient developing recurrent acute edema blisters as a consequence of cutaneous hereditary angioedema attacks.


Assuntos
Angioedemas Hereditários/complicações , Vesícula/diagnóstico , Vesícula/etiologia , Doença Aguda , Angioedemas Hereditários/patologia , Vesícula/patologia , Humanos , Masculino , Pessoa de Meia-Idade
7.
Allergy ; 62(5): 539-46, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17441794

RESUMO

BACKGROUND: Chronic urticaria is one of the most common and disturbing cutaneous condition. The treatment of chronic idiopathic urticaria (CIU) is still a challenge. Antihistamines are recommended as first-line treatment. Rupatadine is a new potent nonsedative anti-H1. OBJECTIVE: To study rupatadine efficacy and safety for moderate to severe CIU treatment. METHODS: This randomized, double-blind, placebo-controlled, parallel-group, multicentre, study was designed to assess primarily mean pruritus score (MPS) reduction with rupatadine, 10 and 20 mg, administered once daily for 4 weeks. Three hundred and thirty-three patients with active episodes of moderate-to-severe CIU were included. RESULTS: A 57.5% (P < 0.005) and 63.3% (P = 0.0001) significative MPS reduction from baseline, was observed at week 4 with 10 and 20 mg rupatadine, respectively, compared with placebo (44.9%). Both doses of rupatadine were not significantly different at any time point, with respect to their effects on pruritus severity, number of wheals and total symptoms scores. Rupatadine 10 mg had an overall better adverse event profile. CONCLUSION: Rupatadine 10 mg is a fast, long-acting, efficacious and safe treatment option for the management of patients with moderate-to-severe CIU.


Assuntos
Ciproeptadina/análogos & derivados , Urticária/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Doença Crônica , Ciproeptadina/efeitos adversos , Ciproeptadina/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
Clin Exp Immunol ; 147(3): 456-64, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17302894

RESUMO

UNLABELLED: We have analysed the phenotype of T lymphocytes in two X-linked lymphoproliferative disease (XLP) patients with the same SH2D1A mutation differing in initial exposure to Epstein-Barr virus (EBV) and treatment. While memory T lymphocytes (with low CCR7 and CD62L expression) prevailed in both XLP patients, in patient 9, who developed acute infectious mononucleosis (AIM) and received B cell ablative treatment, the predominant phenotype was that of late effector CD8 T cells (CD27-, CD28-, CCR7-, CD62L-, CD45 RA+, perforin+), while in patient 4 (who did not suffer AIM) the prevalent phenotype of CD8 T lymphocytes was similar to that of normal controls (N) or to that of adult individuals who recovered from AIM: CD27+ , CD28+, CCR7-, CD62L-, CD45 RO+ and perforin-. CD57 expression (related to senescence) was also higher in CD8 T cells from patient 9 than in patient 4, AIM or N. Persistently high EBV viral load was observed in patient 9. The results obtained from this limited number of XLP patients suggest that events related to the initial EBV encounter (antigen load, treatment, cytokine environment) may have more weight than lack of SH2D1A in determining the long-term differentiation pattern of CD8 memory T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Transtornos Linfoproliferativos/imunologia , Adulto , Ligante CD27/sangue , Antígenos CD28/sangue , Linfócitos T CD4-Positivos/imunologia , Pré-Escolar , Doenças Genéticas Ligadas ao Cromossomo X/virologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Memória Imunológica , Imunofenotipagem , Mononucleose Infecciosa/complicações , Mononucleose Infecciosa/imunologia , Interferon gama/biossíntese , Transtornos Linfoproliferativos/virologia , Masculino , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/sangue , Carga Viral
9.
Clin Exp Immunol ; 147(1): 99-105, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17177968

RESUMO

Diclofenac (Dc) induces an IgE-independent basophil (Ba) degranulation in susceptible individuals. CD63 Ba expression is utilized as an in vitro test for diagnosis of drug hypersensitivity. We tested the ability of Dc to induce CD63 Ba expression by flow cytometry (BAT) and Ba degranulation using light microscopy (HBDT) in patients sensitive to Dc. We studied 14 patients with diclofenac hypersensitivity, also two patients sensitive to Dermatophagoides pteronyssinus (Dp), and 12 normal controls. HBDT was performed by mononuclear cells toluidine blue staining. BAT determined CD63 expression in antiCD63/anti-IgE/anti-CD45-labelled whole blood. In each case, the percentage of activated Ba post-stimulation with 1 and 10 microg/ml Dc was determined. Positive controls included N-formyl-methionyl-leucyl-phenylalanine (fMLP) peptide-induced activation. IgE-mediated Ba activation was induced with a Dp allergenic extract. With Dc 1 microg/ml, mean HBDT in Dc-susceptible individuals was 33.62 +/- 18.35% and 8.49 +/- 4.79% in controls (P = 0.0001). Mean BAT was 2.04 +/- 1.68% and 1.93 +/- 1.40% in controls (P = 0.8). Ba preincubation with Dc did not affect fMLP-induced CD63 expression, neither in Dc-sensitive individuals (P = 0.8) (n = 4) nor in subjects without Dc hypersensitivity (P = 0.25) (n = 4). Ba from the two patients sensitive both to Dc and Dp responded to Dp but not to Dc by BAT: Dc, 1.99 +/- 0.78%; Dp: 60.87 +/- 9.28%; but showed degranulation by HBDT: Dc, 30.53 +/- 1.02%, Dp: 48.78 +/- 22.17%. Dc induces Ba degranulation in sensitive patients in a way that does not induce CD63 expression and is different from IgE-mediated and fMLP-mediated degranulation. Our results suggest that CD63 expression is not a reliable diagnostic method for diclofenac allergy.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antígenos CD/análise , Basófilos/imunologia , Diclofenaco/farmacologia , Hipersensibilidade a Drogas/imunologia , Glicoproteínas da Membrana de Plaquetas/análise , Alérgenos/imunologia , Alérgenos/farmacologia , Animais , Antígenos CD/imunologia , Teste de Degranulação de Basófilos , Basófilos/efeitos dos fármacos , Biomarcadores/análise , Estudos de Casos e Controles , Dermatophagoides pteronyssinus/imunologia , Citometria de Fluxo , Humanos , Hipersensibilidade/imunologia , Imunização , Imunoglobulina E/imunologia , Glicoproteínas da Membrana de Plaquetas/imunologia , Sensibilidade e Especificidade , Tetraspanina 30
10.
Medicina (B.Aires) ; Medicina (B.Aires);65(3): 231-234, 2005. graf
Artigo em Espanhol | LILACS | ID: lil-425254

RESUMO

La urticaria crónica es una enfermedad frecuente, caracterizada por la presencia de ronchas y/o angioedema con una duración superior a las 6 semanas. En un número importante de pacientes se comporta como una enfermedad autoinmune asociada frecuentemente con alteraciones en la función tiroidea y com la presencia de anticuerpos antitiroideos. Presentamos una serie de 70 pacientes consecutivos con diagnóstico de urticaria crónica a los cuales les investigamos la función tiroidea y la presencia de anticuerpos antiperoxidasa tiroidea. Siete (10%) tenían diagnóstico de enfermedad tiroidea previa al momento de la consulta. A los 63 pacientes restantes se les estudió los niveles de tirotrofina sérica, 11 de los cuales (17%) presentaron valores anormales, que sumados a los 7 con enfermedad previa llegan a 18 (26%) con función tiroidea alterada. A 61 pacientes se les investigo anticuerpos antiperoxidasa tiroidea, 22 (36%) fueron positivos. De 57 pacientes sin diagnóstico de patología tiroidea previa al momento de la consulta por urticaria, a los que se les estudió tanto los niveles de tirotrofina sérica como la presencia de anticuerpos antiperoxidasa tiroidea, 24 (42%) presentaron alguno de los estudios alterados. El alto porcentaje de alteraciones tiroideas en nuestra serie de pacientes resalta la necesidad de estudiar la función tiroidea y la presencia de anticuerpos antiperoxidasa tiroidea en pacientes con urticaria crónica.


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Iodeto Peroxidase/sangue , Tireoidite Autoimune/complicações , Tireotropina/sangue , Urticária/etiologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Biomarcadores/sangue , Doença Crônica , Iodeto Peroxidase/imunologia , Tireoidite Autoimune/diagnóstico , Tireoidite Autoimune/imunologia , Tireotropina/imunologia , Urticária/imunologia
11.
Medicina (B Aires) ; 60(6): 947-50, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-11436706

RESUMO

Kikuchi-Fujimoto disease (KFD) is a form of necrotizing lymphadenitis. The disease is a usually benign, self limited cause of lymph node enlargement affecting predominantly young women. Several other clinical manifestations have been described, though the only consistent findings are a macular eruption and a fever. Occasionally, the disease has presented as a fever of unknown origin. Lymph node specimens show areas of necrosis without neutrophilic infiltration. Lymphocyte mediated apoptotic mechanisms are responsible for the necrosis observed. Clinically, it should be differentiated from many different conditions, including infections such as cat scratch disease and rheumatological diseases like Still's disease and Systemic Lupus Erythematosus. Pathologically, it should be differentiated from lymphomas. KFD is widely known in the Far East, but very rare in Latin America. As a matter of fact, we have only detected four reported cases from Argentina, Brazil and Chile. We here describe two additional cases from Argentina. Both occurred in young women. One had a mediastinal compromise and a recurrent course, only observed in 4% of cases. The second one had a classical cervical presentation. The diagnosis in both was made by lymph node biopsy, although, in areas of great prevalence, an aspiration may be sufficient to establish the disease. We anticipate that the real prevalence of this unusual disease is highly underrepresented.


Assuntos
Linfadenite Histiocítica Necrosante/patologia , Adulto , Feminino , Humanos , Pessoa de Meia-Idade
14.
Medicina (B Aires) ; 54(3): 230-6, 1994.
Artigo em Espanhol | MEDLINE | ID: mdl-7854089

RESUMO

As a result of IgG-Fc interaction, sheep erythrocytes sensitized with IgG (E-IgG) are constitutively phagocytosed by resting PMN, although in low numbers. The low efficiency of the system can be improved by opsonization with C3b, since the combination of C3b and IgG makes a powerful opsonic signal. It is accepted that the mechanism of C3b enhancement of IgG mediated phagocytosis is achieved by increasing the adherence of the targets to the phagocyte. Recently, a non-opsonic role for C3b enhancement of IgG mediated phagocytosis has been proposed, in cultured human monocytes. These cells, when adhered on glass surfaces precoated with C3b, showed a marked increase in E-IgG internalization. The effect was dose dependent and it was reproduced utilizing a monoclonal antibody against CR1 (C3b receptor). In the present work we studied the existence of this phenomenon in resting neutrophils and in neutrophils stimulated with two kinds of agents: a phorbol ester (PDBu), which activates the CR1 and fMLP, which increases the expression of this receptor. In previous experiments we determined that the adherence of resting neutrophils on different concentrations of iC3 (which binds CR1 and exerts the same effect that C3b), did not increase the phagocytosis of the E-IgG, using as a control neutrophils adhered on the same concentrations of human serum albumin (HSA) (data not shown).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Monócitos/fisiologia , Neutrófilos/fisiologia , Fagocitose/fisiologia , Receptores de Complemento 3b/fisiologia , Receptores Fc/fisiologia , Humanos , Monócitos/efeitos dos fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Dibutirato de 12,13-Forbol/farmacologia
15.
Medicina (B.Aires) ; Medicina (B.Aires);54(3): 230-6, 1994. graf
Artigo em Espanhol | LILACS | ID: lil-141786

RESUMO

El preligamiento del receptor de C3b (CR1) con su ligando potencia la fagocitosis mediada por el receptor para Fc (FcR) en monocitos cultivados, pero no en monocitos frescos. Nuestros estudios se dirigieron a establecer si la cooperación CR1-FcR ocurre en neutrófilos en reposo o activados. Activando neutrófilos con dosis de 1 a 5 ng/ml de PDBu observamos estimulación de la fagocitosis via Fc, mientras que a concentraciones mayores hubo una inhibición de la misma. La adherencia de las células sobre C3 inactivado (iC3) en forma simultánea al tratamiento con dosis estimulatorias o subinhibitorias de PDBu no incrementó la ingestión de eritrocitos de carnero sensibilizados con IgG (E-IgG); aun variando la cantidad de anticuerpo sensibilizante o estimulando a las células con PDBu durante distintos tiempos. La estimulación de los neutrófilos con diferentes concentraciones de fMLP en forma simultánea a la adherencia sobre iC3 tampoco incrementó la fagocitosis de los blancos mediada por el FcR. La comunicación entre el CR1 y el FcR difere en neutrófilos y monocitos, hecho que podría relacionarse con el mecanismo de activación del CR1 y la clase de FcR encontrado en cada tipo de celular


Assuntos
Animais , Fagocitose/imunologia , Receptores Imunológicos/imunologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos , Neutrófilos/imunologia , Fagocitose/efeitos dos fármacos , Dibutirato de 12,13-Forbol/farmacologia , Receptores de Complemento 3b/imunologia , Receptores Fc/imunologia
17.
J Immunol ; 146(10): 3356-64, 1991 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-1902854

RESUMO

The regulation of Ig production by human B lymphocytes is a complex process involving interactions among B cells, APC, T lymphocytes and soluble factors including activation, growth, and differentiation factors. Components of the complement system, including C3a, C3b, C3d, and C5a, have been shown to influence various stages in this process. In this study, we demonstrate that the C1q subcomponent of complement binds to both small resting and large activated B cells and stimulates immunoglobulin production by Staphylococcus aureus Cowan-activated tonsillar B lymphocytes. This effect is present whether C1q is added to the B cells either at the beginning or near the end of a 7-day culture period and is not associated with enhancement of proliferation. The C1q stimulation of Ig production is, however, associated with increased steady state levels of mRNA for the mu Ig H chain. Furthermore, C1q stimulated IgM production by the human B cell line SKW 6.4, which is capable of secreting IgM in response to B cell differentiation factors (BCDF). SLE is a disorder frequently associated with polyclonal activation of B lymphocytes. We studied the effect of C1q on B cells from two patients with this disorder and one with an SLE-like illness, all selected for the predominance of either IgM or IgG in serum. Spontaneous or BCDF-stimulated Ig secretion was of the isotype predominant in vivo, whereas C1q selectively stimulated B cells to produce the other isotype (IgG vs IgM). Thus, C1q interacts with B lymphocytes in a manner distinct from that of BCDF found in mixed lymphocyte supernatants. C1q may be an important factor influencing the production of Ig by B lymphocytes in normal individuals and in patients with abnormalities of B cell activity.


Assuntos
Linfócitos B/imunologia , Complemento C1q/fisiologia , Imunoglobulinas/biossíntese , Células Cultivadas , Humanos , Isotipos de Imunoglobulinas/biossíntese , Imunoglobulina M/biossíntese , Cadeias mu de Imunoglobulina/biossíntese , Ativação Linfocitária , RNA Mensageiro/análise , Staphylococcus aureus/imunologia
18.
J Immunol ; 146(8): 2694-700, 1991 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1826698

RESUMO

Opsonization of the C3b receptor (CR1) on phagocytic cells with C3b enhances both attachment of targets to the cells and subsequent IgG-dependent ingestion of these targets. To explore mechanisms involved in this increased phagocytosis, we adhered cultured human monocytes to surfaces pre-coated with CR1 ligand or control proteins and quantitated ingestion of sheep E opsonized with IgG alone. Three ligands for CR1 resulted in markedly enhanced phagocytosis of targets when compared individually to a panel of non-ligands, as determined by both the proportion of monocytes ingesting targets (percent phagocytosis) and by the number of targets ingested per 100 monocytes (phagocytic index). The ligands included purified C3b, iC3, and Fab fragments of 1B4, a monoclonal anti-CR1, which resulted in a percent phagocytosis of 56.3 (p less than 0.01), 59.0 (p less than 0.01), and 54.4 (p less than 0.02) and a phagocytic index of 281.2 (p less than 0.01), 281.1 (p less than 0.01), and 247.1 (p less than 0.02), respectively. Control proteins including human serum albumin, hemoglobin, Fab fragments of anti-fibronectin, anti-beta 2 microglobulin, and MOPC 21, and Fc fragments of 1B4 and MOPC 21 produced no significant stimulation of phagocytosis, nor did F(ab')2 fragments of monoclonal anti-CR3, M1/70. CR1-specific augmentation of target ingestion was apparent with monocytes cultured in serum-free medium for 1 to 7 days, but was not seen with freshly elutriated cells. Phagocytosis of unopsonized or IgM-coated targets was minimal. These results suggest that the adherent monocytes are primed by CR1 cross-linking for enhanced FcR-mediated phagocytosis even when the CR1 ligand is not present on the targets. This contrasts with the behavior of CR3, and demonstrated functional divergence between these C3 fragment receptors in the phagocytic process.


Assuntos
Imunoglobulina G/fisiologia , Monócitos/imunologia , Fagocitose/imunologia , Receptores de Complemento/fisiologia , Anticorpos Monoclonais/farmacologia , Complemento C3c/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , Relação Dose-Resposta a Droga , Humanos , Fragmentos Fab das Imunoglobulinas/farmacologia , Imunoglobulina M/farmacologia , Técnicas In Vitro , Receptores de Complemento 3b , Albumina Sérica/farmacologia , Fatores de Tempo
19.
Thromb Haemost ; 64(1): 32-7, 1990 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-2125757

RESUMO

In a patient with a Lupus Anticoagulant (LA) and recurrent fetal loss, we observed a significant shortening of the APTT after high-dose intravenous immunoglobulin infusion (IVIg). The LA activity present in patient's serum and purified IgG was partially neutralized by IVIg in a dose-dependent way. In addition, IgG purified from IVIg and its F(ab')2 fragment neutralized LA activity of the patient's IgG. In both cases, the neutralization was dose-dependent and it was obtained with similar molar ratios. The "in vitro" neutralization of LA activity and the immediate shortening of the APTT after IVIg infusion, might be mediated through idiotype/antiidiotype interactions. On the other hand, the long-lasting effect of IVIg in this patient indicates that it may induce specific inhibition of autoantibody synthesis. We believe that IVIg should be considered as a therapeutic alternative for LA-related clinical disorders.


Assuntos
Autoanticorpos/imunologia , Fatores de Coagulação Sanguínea/imunologia , Imunoglobulinas/imunologia , Aborto Espontâneo/imunologia , Adulto , Testes de Coagulação Sanguínea , Relação Dose-Resposta Imunológica , Feminino , Morte Fetal/imunologia , Humanos , Hidrólise , Imunoglobulina G/isolamento & purificação , Imunoglobulinas/administração & dosagem , Infusões Intravenosas , Inibidor de Coagulação do Lúpus , Pepsina A , Gravidez
20.
J Allergy Clin Immunol ; 81(6): 1199-204, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2454251

RESUMO

We describe a mechanism of action of autoantibodies reactive with the C1 esterase inhibitor (C1EI) molecule found in three patients with acquired angioedema without associated diseases. All of these patients have a circulating C1EI of lower molecular weight than that of normal control subjects. When native C1EI was added to patient, but not control, plasmas, it was cleaved to a lower molecular weight fragment under conditions that allowed contact system activation. In a partially purified system, patient immunoglobulin preparations impaired stable complex formation between plasmin and C1EI and exaggerated the cleavage of the latter to a lower molecular weight fragment. We propose that the autoantibody does not interfere with the cleavage of the bait sequence of the inhibitor but reduces the availability of the reactive center of the molecule in a way that interferes with the irreversible inhibition of target enzymes. In this way unregulated activation of the kinin and complement pathways occurs, leading to disease manifestations via as yet uncharacterized mediators.


Assuntos
Angioedema/imunologia , Autoanticorpos/fisiologia , Doenças Autoimunes/imunologia , Proteínas Inativadoras do Complemento 1/imunologia , Angioedema/sangue , Reações Antígeno-Anticorpo , Doenças Autoimunes/sangue , Sítios de Ligação de Anticorpos , Proteínas Inativadoras do Complemento 1/sangue , Proteínas Inativadoras do Complemento 1/isolamento & purificação , Epitopos/imunologia , Humanos , Imunoglobulinas/fisiologia , Peso Molecular
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