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Val247Leu polymorphism of beta(2) glycoprotein 1 gene may justify the genesis of anti beta(2)GP1 antibodies and Antiphospholipid Syndrome in Multibacillary Leprosy

BROCHADO, Maria Jose Franco; NASCIMENTO, Margarida Maria Passeri do; LOUZADA-JUNIOR, Paulo; FIGUEIREDO, Jose Fernando C.; ROSELINO, Ana Maria
Fonte: SOC BRASILEIRA DERMATOLOGIA Publicador: SOC BRASILEIRA DERMATOLOGIA
Tipo: Artigo de Revista Científica
Português
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36.32%
BACKGROUND - Multibacillary (MB) leprosy may be manifested with antiphospholipid antibodies (aPL), among which anti-beta(2)GP1 (beta(2)-glycoprotein 1). High titers of aPL are associated with APS (Antiphospholipid Syndrome), characterized by thrombosis. The mutation Val247Leu in the domain V of beta(2)GP1 exposes hidden epitopes with consequent development of anti-beta(2)GP1 antibodies. OBJECTIVE: To evaluate the Val247Leu polymorphism of beta(2)GP1 gene and its correlation with anti-beta(2)GP1 antibodies in leprosy patients. METHODS: The Val247Leu polymorphism was performed by PCR-RFLP and anti-beta(2)GP1 antibodies were measured by ELISA. RESULTS: The genotypic Val/Val was more prevalent in the leprosy group, compared to controls. Regarding the 7 MB patients with APS, four presented heterozygosis and three, Val/Val homozygosis. Although higher titrations of anti-beta(2)GP1 IgM antibodies were seen in MB leprosy group with Val/Leu and Val/Val genotypes, there was no statistical difference when compared to Leu/Leu genotype. CONCLUSION: The prevalence of Val/Val homozygosis in leprosy group can partially justify the presence of anti-beta(2)GP1 IgM antibodies in MB leprosy. The description of heterozygosis and Val/Val homozygosis in 7 patients with MB leprosy and thrombosis corroborates the implication of anomalous phenotype expression of beta(2)GP1 and development of anti-beta(2)GP1 antibodies...

Anti-nucleosome and anti-chromatin antibodies are present in active systemic lupus erythematosus but not in the cutaneous form of the disease

SOUZA, A.; SILVA, L. M. da; OLIVEIRA, F. R.; ROSELINO, A. M. F.; LOUZADA-JUNIOR, P.
Fonte: SAGE PUBLICATIONS LTD Publicador: SAGE PUBLICATIONS LTD
Tipo: Artigo de Revista Científica
Português
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36.38%
The objective of this study is to investigate the presence of anti-nucleosome (anti-NCS) and anti-chromatin (anti-CRT) antibodies in patients with cutaneous lupus erythematosus (CLE) compared with active and inactive systemic lupus erythematosus (SLE). A total of 154 subjects were evaluated: 54 patients presenting CLE, 66 patients with active SLE and 34 with inactive SLE. Lupus activity was assessed using the disease activity index (SLEDAI). Anti-NCS and anti-CRT antibodies were detected by enzyme-linked immunosorbent assay ( ELISA). Only one of 54 patients with CLE tested positive for both anti-NCS and anti-CRT antibodies. The prevalence of anti-CRT antibodies was significantly higher in active SLE (84.8%) when compared with inactive SLE (26.4%) and CLE (1.8%) ( P < 0.001). Anti-NCS antibodies were also more prevalent in active SLE patients (74.2%) than inactive SLE (11.7%) and CLE patients ( 1.8%) ( P < 0.001). The presence of anti-CRT and anti-NCS antibodies was correlated to disease activity in patients with SLE (r = 0.4937, r = 0.5621, respectively). Furthermore, the detection of both antibodies was correlated with disease activity in patients with SLE who tested negative for anti-dsDNA antibodies ( r = 0.4754 for anti-NCS and r = 0.4281 for anti-CRT). The presence of these two auto-antibodies was strongly associated with renal damage in patients with SLE ( OR = 13.1...

The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study

David-Neto, Elias; Souza, Patricia Soares; Panajotopoulos, Nicolas; Rodrigues, Helcio; Ventura, Carlucci Gualberto; Ribeiro David, Daisa Silva; Carvalhinho Lemos, Francine Brambate; Agena, Fabiana; Nahas, William Carlos; Kalil, Jorge Elias; Ribeiro Castro
Fonte: HOSPITAL CLINICAS, UNIV SAO PAULO; SAO PAULO Publicador: HOSPITAL CLINICAS, UNIV SAO PAULO; SAO PAULO
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.33%
OBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short-and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T-and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%). Antibodies were detected using a solid-phase (Luminex (R)), single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19%) developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57%) exhibited complete clearance of the donor-specific antibodies. Five other patients developed "de novo' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection...

Anticorpos séricos anti Escherichia coli enterohemorrágica (EHEC) em adultos saudáveis da Grande São Paulo; Seric antibodies anti-hemorrhagic Escherichia coli (EHEC) in healthy Brazilian adults

Quintanilla, Lucy Beatriz Zapata
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/03/2005 Português
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As gastroenterites ainda são um importante problema de saúde pública nos países em desenvolvimento e as Escherichia colí são as principais causas de diarréias. Adultos brasileiros apresentam anticorpos reativos com E. colí enteropatogênica (EPEC), que apresenta muitas semelhanças com E. colí enterohemorágica (EHEC) e pode ser responsável por complicações como a síndrome hemolítica urêmica e a colite hemorrágica. Ambas as bactérias apresentam um mecanismo patogênico comum: a formação da lesão "attaching and effacing" nos microvilus dos enterócitos, mediadas por fatores de virulência, como Intimina, Tir e as Esps. Os lipopolissacarídeos (LPS) são componentes da membrana externa das bactérias gram-negativas, incluindo E. colí. A infecção por EHEC 0157 resulta na produção de anticorpos séricos antiLPS 0157, que geralmente são indicativos de infecção recente. Neste trabalho, nós investigamos a presença de anticorpos séricos IgG e IgM anti-EHEC 0157:H7, EHEC 0111:H- e EPEC 0111:H- em adultos brasileiros, da Grande São Paulo. Amostras de soro foram coletadas de 200 adultos saudáveis, doadores de sangue, e um pool foi formado com 100 amostras. Anticorpos foram determinados em 100 amostras individuais por ELlSA com bactérias íntegras e anti-LPS para a determinação de anticorpos específicos anti-LPS 0111 e 0157 com o "pool" de soro como controle...

Transferência transplacentária de anticorpos anti-Streptococcus B nos recém-nascidos de termo e pré-termo; Placental transfer of anti-Streptococcus B antibodies in term and preterm newborn babies

Brasil, Tatiana Braga
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 25/06/2008 Português
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O Streptococcus do Grupo B (EGB) é um dos principais agentes de infecção no período neonatal, sendo responsável por altos índices de morbimortalidade materno-fetal. Este estudo tem por objetivo avaliar a passagem transplacentária de anticorpos anti-Streptococcus B e imunoglobulina G em recém-nascidos de termo e pré-termo, bem como comparar seus níveis séricos. Foi realizado estudo transversal incluindo 44 recém-nascidos (18 pré-termo e 26 de termo) do Berçário Anexo à Maternidade do Hospital das Clínicas da FMUSP no período de dezembro de 2006 a julho de 2007. Após consentimento esclarecido, foram obtidas amostras de sangue das mães e do cordão umbilical de seus respectivos recém-nascidos, realizadas dosagens de IgG total por nefelometria e de anticorpos anti-EGB através do ensaio imunoenzimático (ELISA). Observou-se que nos dois grupos de mães da casuística, compostos por 16 mães de RN pré-termo e 26 mães de RN de termo, não houve diferença significativa em relação aos níveis séricos de anticorpos anti-EGB. O nível sérico médio de anticorpos maternos anti-EGB foi de 1697,98, com variação de 456 a 5200 (em títulos). O nível sérico médio de anticorpos anti-EGB das mães de RNPT foi de 1570...

Pesquisa de anticorpos anti-megalina em pacientes transplantados renais; Anti-megalin antibodies in kidney transplantation

Borba, Susan Caroline Pinto
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/06/2010 Português
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Introdução: O papel do sistema HLA na evolução do transplante é indiscutível. Dados da literatura internacional e do nosso laboratório têm mostrado que este não é o único sistema envolvido nos processos de RMA (rejeição mediada por anticorpo) Esse fato é comprovado a partir da constatação de que transplantes realizados entre irmãos com total identidade HLA também são alvos da RMA. Entretanto, os alvos antigênicos desses anticorpos permanecem desconhecidos, dificultando assim o diagnostico e tratamento da RMA não-HLA. No transplante renal a presença desses anticorpos têm sido associada com anticorpos anti células endoteliais, células epiteliais tubulares, podocitos, células mesangiais e monócitos. Nosso objetivo neste estudo foi avaliar a presença e a relevância clínica de anticorpos contra a megalina, membro da família de receptores de LDL, expressa na membrana apical dos túbulos proximais, com importante papel na reabsorção de proteínas no rim. Métodos: Soros pré-transplante de 105 pacientes submetidos a transplante renal, realizado no Serviço de Transplante Renal do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (UTR-HC-FMUSP) foram testados por ELISA contra 2 peptídeos da megalina estudados e sintetizados em nosso laboratório. (convencionalmente chamados 18 e 19) Resultado: Não foi detectada a presença de anticorpos do isotipo IgG nas amostras prétransplante dos pacientes estudados. Entretanto...

Persistência de anticorpos neutralizantes anti-febre amarela em pessoas com 60 anos ou mais previamente vacinadas; Persistence of neutralizing antibodies anti-yellow fever in persons aged 60 years and older previously vaccinated

Miyaji, Karina Takesaki
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 05/05/2015 Português
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INTRODUÇÃO: A Febre Amarela (FA) é uma doença viral aguda endêmica em grande parte do Brasil. A principal medida de prevenção é a vacinação. O presente estudo avaliou a prevalência e os títulos de anticorpos neutralizantes em pessoas com 60 anos ou mais que haviam recebido anteriormente a vacina de FA 17DD, em comparação a adultos saudáveis com 18 a 59 anos. Além disso, foram avaliadas a correlação entre os títulos de anticorpos e o tempo decorrido desde a vacinação, nos participantes que receberam apenas uma dose da vacina, e a prevalência de anticorpos nos vacinados há menos e há mais de dez anos. MÉTODOS: Os participantes foram recrutados entre pessoas que procuraram o Centro de Referência para Imunobiológicos Especiais (CRIE) do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) para receber diferentes vacinas e que referiam ter recebido a vacina de FA anteriormente. Os seguintes dados foram coletados: idade, etnia, sexo, número de doses da vacina de FA recebidas, data da última vacinação de FA. Foi realizada contagem de linfócitos TCD4+ usando citometria de fluxo. Os anticorpos neutralizantes contra FA foram dosados pelo teste de neutralização por redução de 50% das placas de lise (PRNT50). RESULTADOS: Foram incluídos 94 indivíduos...

Autoimmune antibodies anti-AchR as biomarkers in Myasthenia Gravis

Antunes, Raquel Coelho Loyo Pequito
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2014 Português
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Tese de mestrado, Ciências Biofarmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2014; Myasthenia Gravis (MG) is an autoimmune disease triggered by antibodies directed against proteins involved in cell signaling at the neuromuscular junctions, resulting in failure of the neuromuscular transmission and muscle weakness (Conti-Fine et al., 2006). The majority of these autoantibodies (≈85%) are directed to the nicotinic acetylcholine receptor (anti-AchR antibodies) present in skeletal muscle cells, but the exact area of the receptor that is targeted is still not known (Tzartos et al., 1991). There is however a significant group of patients that do not express these antibodies. This heterogeneity may be associated with different characteristics regarding the specific target, the affinity or avidity of the antibodies and it may account for different clinical phenotypes. Furthermore, due to the non-specificity of the drugs currently available, some patients respond poorly or not respond at all to treatment. Recently, patients with MG have been treated with Rituximab, a drug that targets CD20 positive cells, (a membrane associated phosphoprotein present in the surface of every B-cell, except stem cells, pro-B-cells and effector B-cells)...

Antibodies to the atherosclerotic plaque components beta2-glycoprotein I and heat-shock proteins as risk factors for acute cerebral ischemia

Staub,Henrique Luiz; Norman,Gary Lewis; Crowther,Tiffany; Cunha,Viviane Roseli da; Polanczyk,Aline; Bohn,Jussara Maria; Fernandes,Jefferson Gomes; Chahade,Wiliam Habib; Mühlen,Carlos Alberto von
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2003 Português
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36.32%
One third of cases of cerebral ischemia have no clear etiology. A humoral response to the atherosclerotic plaques components beta2-glycoprotein l (beta2-gpl) and heat-shock proteins (Hsp) might be involved in the pathogenesis of stroke. This case-control study includes a complete profile of anti-beta2-gpl antibodies and testing of IgG antibodies to the 60/65 kilodaltons (kDa) Hsp in stroke patients. Ninety-three patients with acute ischemic stroke and 93 controls were evaluated for age, sex, race, hypertension, smoking, previous cardiopathy, diabetes mellitus, hypercholesterolemia and previous history of cerebral ischemia. lgG/lgM/lgA anticardiolipin (aCL) and anti-beta2-gpl antibodies, as well as lgG antibodies to human 60 kDa Hsp and to Mycobacterium bovis 65 kDa Hsp, were detected by immunoassay. Adjusted odds ratios (OR) were calculated by logistic regression. The adjusted OR for IgA anti-beta2-gpl antibodies was 4.6 (90%Cl 1.5 to 14.3; p = 0.025). The non-adjusted OR for IgG antibodies to Hsp 60 was 26.1. The adjusted OR for IgG antibodies to Hsp 65 was 3.2 (90%Cl 1.2 to 8.3; p = 0.044). The adjusted OR for lgG to any Hsp (60 or 65) was 4.8 (90%Cl 1.9 to 12.1; p = 0.006). This study demonstrates that elevated IgA anti-beta2-gpl and lgG anti-Hsp 60/65 antibodies are associated with increased risk of ischemic stroke. The association occurred independently of other risk factors. This humoral response might link autoimmunity...

Antiparasitic antibodies occur with similar frequency in patients with clinically established multiple sclerosis with or without oligoclonal bands in the cerebrospinal fluid

Fonseca-Papavero,Fabiana Cruz Gomes da; Callegaro,Dagoberto; Gama,Paulo Diniz da; Livramento,Jose Antonio; Vaz,Adelaide Jose; Machado,Luis dos Ramos
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 Português
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36.32%
The "hygiene hypothesis" postulates an inverse relationship between the prevalence of parasitic infections and the frequency of multiple sclerosis (MS). Objective: It was to study whether antibodies against parasites could be demonstrated more frequently in blood serum from MS patients with oligoclonal bands (OCB) than from MS patients without OCB. Methods: We studied serum samples from 164 patients who had previously been analyzed to investigate OCB. Parasitic antibodies were studied through unidimensional electrophoresis of proteins on polyacrylamide gel against Taenia antigens, searching for antiparasitic specific low molecular weight antibodies and also for antiparasitic nonspecific high molecular weight antibodies. Results: Two of the 103 patients with no evidence of OCB had antibodies of low molecular weight and 59 of them had antibodies of high molecular weight. Of the 61 patients with evidence of OCB, one showed antibodies of low molecular weight and 16 showed antibodies of high molecular weight. Conclusion: Antiparasitic antibodies are detected with similar frequency in MS patients with OCB and in MS patients without OCB.

Association between vitamin B12 level and anti-parietal cells and anti-intrinsic factor antibodies among adult Jordanian patients with Helicobacter pylori infection

Ayesh,Mahmoud H.; Jadalah,Khaled; Awadi,Eiman Al; Alawneh,Khaldoon; Khassawneh,Basheer
Fonte: Brazilian Society of Infectious Diseases Publicador: Brazilian Society of Infectious Diseases
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 Português
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36.34%
OBJECTIVE: Evaluate the association of Helicobacter pylori infection with anti-parietal cell antibodies (APCA) and anti-intrinsic factor antibodies (AIFA) and their impact on vitamin B12 serum level. PATIENTS AND METHODS: One hundred patients (M/F: 43/57; age 46.5 ± 17.5 years) who underwent upper gastrointestinal endoscopy at King Abdullah University Hospital, Irbid, Jordan were enrolled in the study. The patients were grouped as H. pylori-infected (n = 81) or H. pylori negative (n = 19) by histopathological examination. Fasting serum vitamin B12 levels, antiparietal cell antibodies and anti-intrinsic factor antibodies for patients and controls were determined. RESULTS: Anti-parietal cell antibodies and anti-intrinsic factor antibodies were positive in 9.9% and 18.5% of H. pylori-positive patients respectively. None of the H. pylori negative subjects had anti-parietal cell antibodies or anti-intrinsic factor antibodies. Serum vitamin B12 level was lower in the H. pylori-infected patients (275 ± 70.4 pg/mL) than in controls (322.9 ± 60.7 pg/mL; p 0.05). H. pylori was positive in 94% of the low-vitamin B12 group compared with 64.6% of the normal-vitamin B12 group (p 0.5). CONCLUSION: Patients with H. pylori infection are more likely to have anti-parietal cell antibodies and anti-intrinsic factor antibodies. There was an association between H. pylori infection and lower vitamin B12 levels. H. pylori infection might be a significant factor in the pathogenesis of autoimmune gastritis.

A comparison between the novel rabbit monoclonal antibodies (SP1 and B644) and mouse antibodies for evaluating estrogen receptor in breast tumors

Rocha,Rafael Malagoli; Nunes,Cristiana Buzelin; Rocha,Gislene Fátima Silva; Oliveira,Flávio Nepomuceno; Sanches,Fernanda Squárcio Fernandes; Gobbi,Helenice
Fonte: Sociedade Brasileira de Patologia Clínica; Sociedade Brasileira de Patologia; Sociedade Brasileira de Citopatologia Publicador: Sociedade Brasileira de Patologia Clínica; Sociedade Brasileira de Patologia; Sociedade Brasileira de Citopatologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2007 Português
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36.32%
BACKGROUND: A novel generation of rabbit monoclonal antibodies has been released recently for estrogen (ER) and progesterone (PR) receptor evaluation in breast cancer by immunohistochemistry. Aims: We compared novel rabbit monoclonal antibodies anti-ER SP1 (LabVision®) and B644 (Cell Marque®) to mouse monoclonal antibodies 1D5 (Dako®) and 6F11 (Novocastra®) using a tissue microarray of breast carcinomas. METHODS: Two cylinders (2 mm diameter) of formalin-fixed paraffin embedded tissue were obtained from 24 invasive breast carcinomas and immunostained by using the anti-ER rabbit and mouse antibodies and the streptavidin-biotin detection system (Biogenex®). Immunostaining was evaluated considering positive those tumors in which more than 10% of the tumor cell nuclei stained. The stain intensity was also evaluated as weak (1), moderate (2), and strong (3). Results: Both rabbit antibodies against ER have similar staining pattern to each other and also to 6F11, but significantly stronger scores compared to mouse 1D5. The rabbit antibodies allow better cost/benefit because of higher working dilutions compared to mouse antibodies using the same procedure. CONCLUSION: The new rabbit antibodies against ER are highly sensitive and reliable in clinical and research immunohistochemical testing of breast carcinomas.

The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study

David-Neto,Elias; Souza,Patricia Soares; Panajotopoulos,Nicolas; Rodrigues,Helcio; Ventura,Carlucci Gualberto; David,Daisa Silva Ribeiro; Lemos,Francine Brambate Carvalhinho; Agena,Fabiana; Nahas,William Carlos; Kalil,Jorge Elias; Castro,Maria Cristina Ri
Fonte: Faculdade de Medicina / USP Publicador: Faculdade de Medicina / USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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36.33%
OBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short- and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T- and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%). Antibodies were detected using a solid-phase (LuminexH), single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19%) developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57%) exhibited complete clearance of the donor-specific antibodies. Five other patients developed 'de novo' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection...

Antibodies against Streptococcus agalactiae Proteins cα and R4 in Sera from Pregnant Women from Norway and Zimbabwe

Moyo, Sylvester R.; Maeland, Johan A.; Mudzori, James
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/2001 Português
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Group B streptococci (GBS) express strain-variable and surface-localized proteins, which are important serotype markers and targets of protective antibodies. These include the cα and R4 proteins, one or the other of which is expressed by approximately 75% of clinical GBS isolates. These proteins have been considered vaccine candidates. In this study, the cα and R4 proteins were extracted by trypsin digestion of GBS and purified by sequential precipitation with trichloroacetic acid and ammonium sulfate followed by gel filtration chromatography. The proteins were used as antigens in an indirect enzyme-linked immunosorbent assay (ELISA) to measure the levels of cα- and R4-reactive antibodies in sera from pregnant women from Norway (n = 100) and from Zimbabwe (n = 124). Antibody levels in the Norwegian group of women were significantly higher than in the Zimbabwean group, and a higher proportion of the Norwegian women contained appreciable levels of antibodies against both proteins. The antibodies traversed the placental barrier. With individual sera, a significant correlation between the anti-cα and anti-R4 antibody levels was observed and each of the two protein antigens effectively competed for human serum antibodies both against itself and against the other antigen. Inhibition ELISA results demonstrated specificity for each of the proteins of immune antibodies raised in rabbits. These results demonstrate that (i) the majority of women of childbearing age have antibodies against cα and R4...

Specificities and Opsonophagocytic Activities of Antibodies to Pneumococcal Capsular Polysaccharides in Sera of Unimmunized Young Children

Soininen, Anu; Karpala, Maijastiina; Wahlman, Sirkka-Liisa; Lehtonen, Hannele; Käyhty, Helena
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /09/2002 Português
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An enzyme immunoassay (EIA) for antibodies to pneumococcal capsular polysaccharides (Pnc PSs) detects in some cases antibodies that are cross-reactive within different Pnc PSs. Recently, it has been suggested that for detection of only serotype-specific antibodies, EIA can be modified by removing cross-reactive antibodies by absorption with an irrelevant PS, e.g., the type 22F PS. The opsonophagocytosis assay measures the functional activities of antibodies in vitro, and the results of that assay correlate with in vivo protection better than measurement of the antibody concentration by EIA. We compared these different methods for measuring antibodies to type 1, 6B, 11A, 14, 19F, and 23F Pnc PSs in the sera of unimmunized young children who had been monitored for pneumococcal carriage, acute otitis media, and acquisition of antibodies to Pnc PSs from 2 to 24 months of age. Serum samples with antibody increases after contact with a pneumococcus of a homologous serotype contained specific antibodies and often had opsonophagocytic activity (OPA) (20 of 46). In samples with antibody increases from children who had not had contact with a pneumococcus of a homologous serotype, the antibodies found to be type specific by conventional EIA were usually cross-reactive and infrequently had OPA (10 of 68). When type 22F PS absorption was used in the EIA...

Specificity and Diversity of Antibodies to Mycobacterium tuberculosis Arabinomannan

Navoa, Josephine Anne D.; Laal, Suman; Pirofski, Liise-Anne; McLean, Gary R.; Dai, Zhongdong; Robbins, John B.; Schneerson, Rachel; Casadevall, Arturo; Glatman-Freedman, Aharona
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /01/2003 Português
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Arabinomannan (AM) is a polysaccharide antigen of the mycobacterial capsule. However, it is uncertain whether AM constitutes an immunologically distinct fraction of Mycobacterium tuberculosis. In this study, we analyzed the repertoire and specificity of antibodies to AM by using AM-binding murine monoclonal antibodies (MAbs) and human serum samples. Murine MAbs were found to be diverse in their specificity to AM and cross-reactivity with other arabinose-containing mycobacterial polysaccharides, with MAb 9d8 binding exclusively to AM. Human antibodies to AM were detected in serum samples from patients with pulmonary tuberculosis (TB), as well as in those from healthy, purified protein derivative-negative controls, with significantly higher titers among patients. The binding of human antibodies to AM was inhibited by MAb 9d8 in three patients with TB but not in controls. MAb 5c11, which recognizes other mycobacterial arabinose-containing carbohydrates in addition to AM, inhibited the binding of serum samples from 75% of patients and 76% of controls. Analysis of human antibodies with murine MAbs to human VH determinants demonstrated diversity among antibodies to AM with qualitative and quantitative differences compared with antibodies to lipoarabinomannan. In summary...

Study of Humoral Immunity to Commensal Oral Bacteria in Human Infants Demonstrates the Presence of Secretory Immunoglobulin A Antibodies Reactive with Actinomyces naeslundii Genospecies 1 and 2 Ribotypes

Cole, Michael F.; Evans, Mishell K.; Kirchherr, Jennifer L.; Sheridan, Michael J.; Bowden, G. H. W.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /05/2004 Português
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The mouths of three human infants were examined from birth to age 2 years to detect colonization of Actinomyces naeslundii genospecies 1 and 2. These bacteria did not colonize until after tooth eruption. The diversity of posteruption isolates was determined by ribotyping. Using immunoblotting and enzyme-linked immunosorbent assay, we determined the reactivity of secretory immunoglobulin A (SIgA) antibodies in saliva samples collected from each infant before and after colonization against cell wall proteins from their own A. naeslundii strains and carbohydrates from standard A. naeslundii genospecies 1 and 2 strains. A. naeslundii genospecies 1 and 2 carbohydrate-reactive SIgA antibodies were not detected in any saliva sample. However, SIgA antibodies reactive with cell wall proteins were present in saliva before these bacteria colonized the mouth. These antibodies could be almost completely removed by absorption with A. odontolyticus, a species known to colonize the human mouth shortly after birth. However, after colonization by A. naeslundii genospecies 1 and 2, specific antibodies were induced that could not be removed by absorption with A. odontolyticus. Cluster analysis of the patterns of reactivity of postcolonization salivary antibodies from each infant with antigens from their own strains showed that not only could these antibodies discriminate among strains but antibodies in saliva samples collected at different times showed different reactivity patterns. Overall...

Massenspektrometrie-basierte Analyse von Tumorzelllinien mit neuartigen peptidspezifischen Antikörpern – ein universeller Ansatz zur Proteomanalyse; Mass spectrometry-based analysis of tumour cell lines using novel peptide-specific antibodies - an universal approach for proteom analysis

Höppe, Sibylle
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
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In der Proteomforschung haben sich massenpektrometriebasierte Strategien zur Schlüsseltechnologie für die Identifizierung von Proteinen entwickelt. Trotz großer Fortschritte in den letzten Jahren stellt die effiziente Präfraktionierung komplexer Proben vor der Analyse eine große Herausforderung dar. Leistungsfähige analytische Plattformen, die für die Proteomanalyse geeignet sind, sind mit massenspektrometriebasierten Systemen entwickelt worden. Hierfür ist jedoch eine aufwändige Probenvorbehandlung notwendig, im Besonderen um niedrig konzentriert Zielproteine nachzuweisen. Meist werden elektrophoretische (2D-Gele) und chromatographische Prinzipien kombiniert und zur Probenfraktionierung eingesetzt. Neuentwicklungen im Bereich immunaffinitätsbasierter Methoden besitzen die Potenz, den sensitiven Nachweis definierter Zielanalyten nach spezifischer Anreicherung deutlich zu verbessern. Durch Kombination einer immunaffinitäts-basierten Fraktionierungsmethode mit einem massenspektrometriebasierten Ausleseverfahren können definierte Zielmoleküle selektiv und sensitiv analysiert und quantifiziert werden. Die Limitierungen der bestehenden immunaffinitätsbasierten Probenpräfraktionierung bestehen in der geringen Verfügbarkeit geeigneter Bindemoleküle und der hieraus resultierenden niedrigen Auflösung dieser Methode. Um diese Limitierungen zu umgehen wurde in dieser Arbeit ein Konzept entwickelt...

Human herpesvirus-8 (HHV-8) antibodies in women from São Paulo, Brazil: association with behavioral factors and Kaposi's sarcoma

Caterino-de-Araujo,Adele; Santos-Fortuna,Elizabeth de los; Carbone,Paulo Henrique Lage; Cibella,Sandra Elisa Lopes; Moreira,Abdiel Aparecido
Fonte: Brazilian Society of Infectious Diseases Publicador: Brazilian Society of Infectious Diseases
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2003 Português
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BACKGROUND: With the spread of AIDS, many HIV-infected women have been diagnosed with Kaposi's sarcoma (KS), especially in Africa. Since the discovery of a novel herpesvirus as the causative agent of KS (human herpesvirus 8 - HHV-8) several seroepidemiological studies have been conducted to identify groups at risk for KS. The risk for women in Brazil has not been studied. MATERIALS AND METHODS: We searched for HHV-8 antibodies in sera obtained from a bank made up of samples from 3 groups of individuals: Group I: 163 HIV-1-infected women attended at an ambulatory clinic in 1994; Group II: 108 children born to HIV-1-infected mothers from 1990 to 1992, their antibodies reflected maternal infection, and Group III: 630 HIV-1-seronegative, healthy women. In-house immunofluorescence and Western-Blot assays based on the BCBL-1 cell line were used to detect anti-latent and anti-lytic HHV-8 antibodies. RESULTS: Group I had an overall frequency of antibodies of 8.6%, with a 1.2% frequency of anti-latent antibodies and an 8.0% frequency of anti-lytic antibodies. Similar results were detected in Group II, i.e., no cases with anti-latent antibodies and a 7.4% frequency of anti-lytic antibodies. In contrast, prevalences of 1.1% anti-latent antibodies and 0.3% anti-lytic antibodies were observed in Group III. CONCLUSIONS: The epidemiologic pattern of HHV-8 in women from São Paulo varies according to behavioral factors...

The impact of pretransplant donor-specific antibodies on graft outcome in renal transplantation: a six-year follow-up study

David-Neto, Elias; Souza, Patricia Soares; Panajotopoulos, Nicolas; Rodrigues, Helcio; Ventura, Carlucci Gualberto; David, Daisa Silva Ribeiro; Lemos, Francine Brambate Carvalhinho; Agena, Fabiana; Nahas, William Carlos; Kalil, Jorge Elias; Castro, Maria
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/2012 Português
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OBJECTIVE: The significance of pretransplant, donor-specific antibodies on long-term patient outcomes is a subject of debate. This study evaluated the impact and the presence or absence of donor-specific antibodies after kidney transplantation on short- and long-term graft outcomes. METHODS: We analyzed the frequency and dynamics of pretransplant donor-specific antibodies following renal transplantation from a randomized trial that was conducted from 2002 to 2004 and correlated these findings with patient outcomes through 2009. Transplants were performed against a complement-dependent T- and B-negative crossmatch. Pre- and posttransplant sera were available from 94 of the 118 patients (80%). Antibodies were detected using a solid-phase (LuminexH), single-bead assay, and all tests were performed simultaneously. RESULTS: Sixteen patients exhibited pretransplant donor-specific antibodies, but only 3 of these patients (19%) developed antibody-mediated rejection and 2 of them experienced early graft losses. Excluding these 2 losses, 6 of 14 patients exhibited donor-specific antibodies at the final follow-up exam, whereas 8 of these patients (57%) exhibited complete clearance of the donor-specific antibodies. Five other patients developed ''de novo'' posttransplant donor-specific antibodies. Death-censored graft survival was similar in patients with pretransplant donor-specific and non-donor-specific antibodies after a mean follow-up period of 70 months. CONCLUSION: Pretransplant donor-specific antibodies with a negative complement-dependent cytotoxicity crossmatch are associated with a risk for the development of antibody-mediated rejection...