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Afr. health sci. (Online) ; 22(2): 125-134, 2022. figures, tables
Article in English | AIM | ID: biblio-1400236


Background: Various international guidelines have been developed regarding Helicobacter pylori (H. pylori) management, as it is infecting more than half of the world's population. Sudan's health system lacks guidelines regarding H. pylori management, leading to a discrepancy in practice. Investigating the current approach could be a step forward in the formulation of a national consensus in the management of H. pylori. Methods: A cross-sectional study was conducted among medical doctors currently working in Khartoum, Sudan. Participants were enrolled from platforms of medical associations through an online questionnaire. The questionnaire was scored out of 25 points, and scoring 13 or above considered a good approach. Data analysis was carried out using Statistical Package for Social Sciences (SPSS). Results: A total of 358 medical doctors participated in the study. The mean (±SD) score was 12.9(±4.5). Those who were using textbooks, campaigns, symposiums or general medical information to their primary Source of knowledge significantly scored higher. The most selected indication for both diagnosis (76.8%) and treatment (67.6%) was an active peptic ulcer. Stool antigen test (SAT) was the most preferred test (70.7%). The majority of respondents selected triple therapy (82.1%) as a first-line regimen. Only 37.7% confirmed the eradication after four weeks of stopping the treatment. They ensure eradication mainly through SAT (29%). Conclusion: A suboptimal approach was noted among medical doctors of Khartoum, Sudan, regarding H. pylori management. Efforts should be invested in forming national guidelines and the implementation of continuous medical education programs.

Peptic Ulcer , Therapeutics , Health Systems , Cross-Sectional Studies , Helicobacter pylori , Antigens , Diagnosis
urol. colomb. (Bogotá. En línea) ; 31(4): 170-176, 2022. ilus
Article in Spanish | LILACS, COLNAL | ID: biblio-1412093


Objetivo Describir la tasa de mortalidad de infección por coronavirus de tipo 2 causante del síndrome respiratorio agudo severo (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, en inglés) y los factores de riesgo asociados a la severidad de la enfermedad en pacientes con trasplante renal de un centro del nordeste colombiano. Materiales y Métodos Estudio descriptivo de una cohorte de pacientes en seguimiento postrasplante renal, en el que se hizo una búsqueda retrospectiva de los que presentaron infección por SARS-CoV-2 entre marzo del 2020 y mayo del 2021. Para el análisis, se incluyeron los pacientes con infección confirmada mediante pruebas de reacción en cadena de la polimerasa (polymerase chain reaction, PCR, en inglés), de antígenos, o de anticuerpos. Se realizó un análisis descriptivo de las variables sociodemográficas y clínicas, y un análisis bivariado de los posibles factores asociados con el riesgo de mortalidad. Resultados Con un total de 307 individuos en seguimiento, se encontró una prevalencia del 14,3% (n = 44) de infección por enfermedad por coronavirus 2019 (coronavirus disease 2019, COVID-19, en inglés). La media de edad fue de 56 años, con predominio del género masculino. El esquema de inmunosupresión más frecuente fue micofenolato­tacrolimus­prednisona. Entre los pacientes infectados, la mortalidad fue del 34,1% (15/44), lo que representa el 4,8% de toda la población a estudio. Maás de la mitad de los pacientes requirieron hemodiálisis, y en el 86,7% fue necesario hacer ajustes en el esquema de inmunosupresión. Conclusión La prevalencia de infección por SARS-CoV-2 en nuestro grupo de trasplantes fue similar a la reportada por otros grupos de trasplante del país, y mayor a la de la población no trasplantada. El valor de creatinina previo a la infección, la edad y las comorbilidades se asociaron con un mayor riesgo de mortalidad.

Objective To describe the mortality related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the risk factors associated with disease severity in patients submitted to a kidney transplant from a center in northeastern Colombia. Materials and Methods The present is a descriptive study of a cohort of patients in follow-up care after kidney transplant, with a retrospective search for those who presented SARS-CoV-2 infection between March 2020 and May 2021. Patients with confirmed infection by polymerase chain reaction (PCR), antigens or antibodies tests were included for analysis. We performed a descriptive analysis of the sociodemographic and clinical variables as well as a bivariate analysis to evaluate the possible factors associated with the risk of mortality. Results With a total of 307 individuals in follow-up care, a prevalence of 14.3% (n = 44) of coronavirus disease 2019 (COVID-19) infection was found. The mean age of the sample was of 56 years, with a male predominance. The most frequent immunosuppression regimen was mycophenolate-tacrolimus-prednisone. Among the infected patients, the mortality rate was of 34.1% (15/44), representing 4.8% of the entire study population. More than half of the patients required hemodialysis, and 86.7% required adjustments to the immunosuppression regimen. Conclusion The prevalence of SARS-CoV-2 infection in our transplant group was similar to that reported by other transplant groups in the country and higher than among the non-transplanted population. The preinfection creatinine value, age, and comorbidities were associated with a higher risk of mortality.

Humans , Male , Female , Middle Aged , Renal Dialysis , Kidney Transplantation , Coronavirus , Severe Acute Respiratory Syndrome , SARS-CoV-2 , COVID-19 , Severity of Illness Index , Adaptation, Psychological , Polymerase Chain Reaction , Risk Factors , Immunosuppression Therapy , Antigens
São Paulo; s.n; s.n; 2022. 116 p. tab, graf.
Thesis in English | LILACS | ID: biblio-1378343


Stem cells are undifferentiated cells that can be distinguished from others by their ability to self-renew and to differentiate into new specific cell types. Mesenchymal stem cells (MSC) are adult stem cells that can be obtained from different sources, such as adipose tissue, bone marrow, dental pulp, and umbilical cord. They can either replicate, originating new identical cells, or differentiate into cells of mesodermal origin and from other germ layers. MSC have been studied as new tools for regenerative therapy. Although encouraging results have been demonstrated, MSC-based therapies still face a great barrier: the difficulty of isolating these cells from heterogeneous environments. MSC are currently characterized by immunolabelling through a set of multiple surface membrane markers, including CD29, CD73, CD90 and CD105, which are also expressed by other cell types. Hence, the present work aimed to identify new specific biomarkers for the characterization of human MSC using DNA aptamers produced by the SELEX (Systematic Evolution of Ligands by EXponential Enrichment) technique. Our results showed that MSC from different origins bound to DNA candidate aptamers, that is, DNA or RNA oligonucleotides selected from random libraries that bind specifically to biological targets. Aptamer-bound MSC could be isolated by fluorescenceactivated cell sorting (FACS) procedures, enhancing the induction of differentiation into specific phenotypes (chondrocytes, osteocytes and adipocytes) when compared to the whole MSC population. Flow cytometry analyses revealed that candidate aptamers bound to 50% of the MSC population from dental pulp and did not present significant binding rates to human fibroblasts or lymphocytes, both used as negative control. Moreover, immunofluorescence images and confocal analyses revealed staining of MSC by aptamers localized in the surfacemembrane of these cells. The results also showed internal staining of human monocytes by our investigated aptamers. A non-specific control aptamer (CNTR APT) obtained from the random pool was then utilized to compare the specificity of the aptamers bound to the analyzed non-apoptotic cells, showing no staining for MSC. However, 40% of the monocytes bound to the CNTR APT. Normalized data based on the cells bound to candidate aptamers compared to those bound to the CNTR APT, revealed a 10 to 16-fold higher binding rate for MSC against 2-fold for monocytes. Despite its low specificity, monocyte-aptamer binding occurs probably due to the expression of shared markers with MSC, since monocytes are derived from hematopoietic stem cells and are important for the immune system ability to internalize/phagocyte external molecules. Given that, we performed a pull-down assay followed by mass spectrometry analysis to detect which MSC-specific protein or other target epitope not coexpressed by monocytes or the CNTR APT would bind to the candidate aptamer. Distinguishing between MSC and monocyte epitopes is important, as both cells are involved in immunomodulatory effects after MSC transplantations. ADAM17 was found to be a target of the APT10, emerging as a possible biomarker of MSC, since its involvement in the inhibition of the TGF signaling cascade, which is responsible for the differentiation of MSC. Thus, MSC with a higher stemness profile should overexpress the protein ADAM17, which presents a catalytic site with affinity to APT10. Another target of Apt 10 is VAMP3, belonging to a transmembrane protein complex that is involved in endocytosis and exocytosis processes during immune and inflammatory responses. Overall, proteins identified as targets of APT10 may be cell surface MSC biomarkers, with importance for MSC-based cell and immune therapies

Células tronco são células indiferenciadas que podem ser distinguidas de outros tipos celulares por meio da habilidade de se auto renovarem e de se diferenciarem em novos tipos celulares. Células tronco mesenquimais (MSC) são células tronco adultas encontradas em diferentes tecidos como tecido adiposo, polpa de dente e cordão umbilical. Estas células podem se autodividir em células idênticas ou se diferenciarem em células de origem mesodermal. Estas células têm sido estudadas em novas aplicações que envolvem terapia regenerativas. Embora resultados encorajadores tenham sido demonstrados, terapias que utilizam MSC ainda encontram uma grande barreira: a dificuldade no isolamento destas células a partir de um ambiente heterogêneo. MSC são caracterizadas por populações positivas em ensaios de imunomarcação para os epítopos membranares CD29, CD73, CD90 e CD105, presentes também em outros tipos celulares. Assim, o presente trabalho tem o objetivo de identificar novos biomarcadores de MSC de origem humana, utilizando aptâmeros de DNA produzidos pela técnica SELEX (Systematic Evolution of Ligands by EXponential Enrichment) como ferramenta. Nossos resultados mostraram que MSC de diferentes origens ligam-se a aptâmeros (oligonucleotídeos de DNA ou RNA que atuam como ligantes específicos de alvos moleculares) de DNA candidatos que atuam no isolamento de MSC por meio da técnica FACS de separação celular, promovendo uma maior indução de diferenciação em células específicas (condrócitos, osteócitos e adipócitos) comparada com a população total de MSC. Análises de citometria de fluxo mostraram que os aptâmeros candidatos se ligam a 50% das MSC de polpa de dente e não apresentam taxa de ligação significante para fibroblastos e linfócitos de origem humana - utilizados como controles negativo. Além domais, imagens de imunofluorescência e confocal mostraram ligação na superfície da membrana de MSC e a marcação interna de monócitos a estes aptâmeros. Portanto, um aptâmero controle (CNTR APT) foi utilizado para comparar a especificidade dos aptâmeros ligados a células viáveis, mostrando a não ligação deste aptâmero a MSC. Porém, 40% da população de monócitos ligou-se ao CNTR APT. Uma normalização baseada na comparação entre as taxas de ligação entre células ligadas com aptâmeros candidatos e o aptâmero controle gerou uma taxa de especificidade entre 10-16 vezes maior para MSC contra 2,5 vezes para os monócitos. Deste modo, embora os resultados tenham mostrado uma taxa de ligação entre monócitos e aptâmeros, as MSC ligadas aos aptâmeros candidatos possuem uma maior taxa de especificidade devido a uma maior presença de antígenos que são expressos em ambas as células. Um ensaio de Pull Down seguido de espectrometria de massas foi utilizado para a identificação de biomarcadores que se ligariam aos aptâmeros candidatos, e que não seriam co-expressos por monócitos e por antígenos ligados ao aptâmero controle. Deste modo, a proteína ADAM17 foi identificada nas amostras de APT10 ligadas às MSC. Tal proteína está relacionada à inibição de uma cascata de sinalização da família de proteínas TGF, responsável pela diferenciação de MSC. Assim, MSC com maior potencial tronco deveriam expressar ADAM17 em maior quantidade. Tal proteína apresenta um sítio catalítico que demonstra interagir com o APT10, de acordo com predição Docking entre proteína e DNA. Foi identificada também, a proteína VAMP3, que pertence a um complexo proteico transmembranar responsável pelos processos de endocitose e exocitose, e que podem ter um papel importante na liberação de citocinas e outras moléculas relacionadas às respostas imune e inflamatórias. Deste modo, o APT10 identificou proteínas importantes que devem estar relacionas com a melhora de imunoterapias que utilizam MSC

Stem Cells , Biomarkers/analysis , SELEX Aptamer Technique/instrumentation , Mesenchymal Stem Cells/classification , ADAM17 Protein/pharmacology , Patient Isolation , Mass Spectrometry/methods , Staining and Labeling/methods , Transplantation/adverse effects , Umbilical Cord , DNA/agonists , Transforming Growth Factors/agonists , Cell Separation/instrumentation , Cytokines/adverse effects , Adipocytes/metabolism , Chondrocytes/classification , Scientists for Health and Research for Development , Adult Stem Cells/classification , Fibroblasts/chemistry , Flow Cytometry/instrumentation , Germ Layers , Antigens/adverse effects
Chinese Journal of Biotechnology ; (12): 1209-1217, 2022.
Article in Chinese | WPRIM | ID: wpr-927775


Recombinant HLA-Ⅰ molecules/antigenic peptide complexes (pHLA complexes) are applied in the research of human T cell-specific immune responses. The preparation of pHLA complex is based on genetic engineering and protein in vitro dilution and folding-refolding technology. In an in vitro refolding system, recombinant HLA-Ⅰ molecules correctly fold and bind with antigenic peptides to form complexes. In this study, ultrafiltration-high performance liquid chromatography (ultrafiltration-HPLC) was used for quantitative determination of the antigenic peptides in recombinant pHLA complexes, especially for those in a small amount of prepared products. By adding the recombinant HLA-Ⅰ molecules and antigenic peptides into the refolding buffer, the heavy chain (HC) and light chain (β2m) of recombinant HLA-Ⅰ molecules were refolded and bond with the VYF antigenic peptide containing anchor residues to form a pHLA complex. The unbound free antigenic peptide VYF was removed by ultrafiltration to retain the complex. Finally, the pHLA complex was treated by acid to destroy its interaction, thus releasing the antigenic peptide. The results showed that the prepared recombinant pHLA complex was recognized by HLA-Ⅰ molecule specific antibody W6/32, which indicated that the recombinant HLA-Ⅰ class molecule had correct folding and was identified as pHLA complex. The antigen peptide VYF contained in the pHLA complex was also detected by ultrafiltration-HPLC, so it is feasible to apply ultrafiltration-HPLC for determination of pHLA complex. Compared with Western blotting, the concentration of antigenic peptides detected by ultrafiltration-HPLC was 0-9 μg/mL. The binding conditions can be optimized according to the amount of antigenic peptides bound in the complex in order to improve the folding efficiency of HLA-Ⅰ molecules and promote the binding of HLA-Ⅰ molecules to antigenic peptides. The production rate of pHLA complexes in the refolding system can also be calculated according to the content of antigenic peptides bound by pHLA complexes. Therefore, ultrafiltration-HPLC in this study can be used for the quality control of the preparation process of pHLA complexes, and may facilitate the research of T cell-specific immunity, artificial antigen-presenting cells, and development of specific tetramer probe applications.

Amino Acid Sequence , Antigens , Chromatography, High Pressure Liquid , Humans , Peptides/chemistry , Ultrafiltration
J. venom. anim. toxins incl. trop. dis ; 28: e20210074, 2022. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1365077


Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiological agent of the disease coronavirus 2019 (COVID-19) in humans. SARS-CoV-2 has been identified in cats with or without clinical signs. Case presentation: We describe the pathological and molecular findings in a six-month-old asymptomatic cat with SARS-CoV-2 infection from Brazil, belonging to a human family with COVID-19 cases. The pool of nasopharynx and oropharynx swabs at day zero tested positive by RT-qPCR for SARS-CoV-2. No amplification resulted from molecular testing performed on days 7 and 14. The cat was hit by a car and died 43 days after the molecular diagnosis. Immunohistochemistry at post-mortem examination demonstrated nucleocapsid protein in samples from the lungs, kidneys, nasal conchae, trachea, intestine, brain and spleen. Conclusion: The present study has highlighted the possibility that viral antigens can be detected by immunohistochemistry in multiple organs six weeks after infection, although the same tissues tested negative by RT-PCR.(AU)

Animals , Cats , Immunohistochemistry , SARS-CoV-2/immunology , COVID-19/diagnosis , Antigens/analysis , Oropharynx , Nasopharynx
Arq. Asma, Alerg. Imunol ; 5(4): 385-394, out.dez.2021. ilus
Article in English | LILACS | ID: biblio-1399793


Eosinophilic esophagitis (EoE) is a chronic inflammation in the esophageal mucosa driven by an antigen-mediated abnormal immune response with apparent increasing prevalence worldwide. Genetically predisposed individuals present with a dysfunctional esophageal barrier and an abnormal immune response mediated by Th2 and IgE against certain allergens. Consequently, esophageal lesions can cause dysmotility, fibrosis and loss of esophageal barrier function. Clinical manifestations are age-related and include symptoms of esophageal dysfunction. Diagnosis is established by specific histological features associated with the presence of at least 15 eosinophils per high-power field. Management of EoE includes control of allergic diseases with diet restrictions and/or pharmacological treatment with proton-pump inhibitors and corticosteroids, not completely effective and limited by possible side effects and impairment of quality of life. Although immunological mechanisms of EoE are still less clear than other allergic diseases, biologic trials indicate some promising perspectives for EoE management. The purpose of this review is to present the current evidence of biologic drugs as options for EoE treatment.

Esofagite eosinofílica (EOE) é uma inflamação crônica da mucosa esofágica com resposta imune antígeno-mediada anormal e com aparente aumento mundial na prevalência. Indivíduos geneticamente predispostos se apresentam com quadro de disfunção da barreira esofágica e uma resposta imune, mediada por TH2 e IGE, anormal contra certos alérgenos. Consequentemente, lesões esofágicas podem causar dismotilidade, fibrose e perda da função de barreira. O quadro clínico apresenta variação conforme idade e inclui sintomas de disfunção esofágica. O diagnóstico é estabelecido por achados histológicos específicos associados à presença de, ao menos, 15 eosinófilos por campo de alta potência. O manejo inclui controle do quadro alérgico com restrição dietética e/ou tratamento medicamentoso com bloqueadores da bomba de prótons e corticosteroides. São tratamentos sem completa efetividade, com efeitos colaterais e prejuízo na qualidade de vida. Ainda que os mecanismos imunológicos da EOE sejam menos claros que as demais doenças alérgicas, novos ensaios com imunobiológicos salientam uma perspectiva promissora de tratamento para a EOE. O objetivo desta revisão é apresentar as atuais evidências de uso de imunobiológicos como uma nova opção de terapêutica para a esofagite eosinofílica.

Humans , Adrenal Cortex Hormones , Diet , Proton Pump Inhibitors , Eosinophilic Esophagitis , Antibodies, Monoclonal, Humanized , Omalizumab , Therapeutics , Biological Products , Fibrosis , Immunoglobulin E , Prevalence , Drug Therapy , Endoscopy , Esophageal Mucosa , Immunity , Inflammation , Antigens
Rev. Investig. Salud. Univ. Boyacá ; 8(2): 110-130, 20211201. tab
Article in Spanish | LILACS, COLNAL | ID: biblio-1369463


Introducción: Para diseñar vacunas es necesario comprender la función de los antígenos de Plasmodium spp. in-volucrados en la invasión a células hospederas. Diferentes investigaciones han generado proteínas recombinantes utilizando sistemas de expresión heterólogos y así han obtenido moléculas semejantes a las nativas. Con estos avances se desarrollan estrategias que bloquean la infección de estos patógenos. Objetivo: Describir las características y los aspectos metodológicos más importantes de los sistemas de expresión de las proteínas recombinantes en estudios funcionales de Plasmodium spp. Metodología: Revisión descriptiva de estudios publicados en Pubmed, Science Direct, Embase y Medline, entre 2010 y 2020, que incluyeran sistemas recombinantes en células de Escherichia coli, de mamífero y sistemas libres de células, para estudios funcionales de antígenos de Plasmodium falciparum y Plasmodium vivax. Se revisaron 70 artículos originales y 58 cumplieron con los criterios establecidos. Resultados: Obtener proteínas recombinantes mediante un sistema procariota, de mayor rendimiento y bajo costo, ha permitido estudiar un número importante de antígenos. Los sistemas con células de mamífero y libres de células, que permiten modificaciones postraduccionales y plegamiento adecuado de moléculas, se usan para producir librerías de antígenos con estructura conformacional similar a la nativa. Conclusión: El estudio de los antígenos de Plasmodium spp. implicados en la infección y desarrollo de células diana requiere una adecuada selección del método de producción recombinante. El refinamiento de procesos de expresión en sistemas procariotas, eucariotas e in vitro, mediante ingeniería genética y cultivo celular, permitirá mejores rendimientos y menor costo.

Introduction: Understanding the function of Plasmodium spp. Antigens involved in invasion of host cells is necessary to design vaccines. Different studies have generated recombinant proteins using heterologous expression systems, obtaining molecules similar to native ones. These advances are es-sential to develop strategies that block the infection of these pathogens. Objective: Describe the most important characteristics and methodological aspects of recombinant protein expression systems in functional studies of Plasmodium spp. Methodology: Descriptive review of studies published in Pubmed, Science Direct, Embase and Medline, between 2010 and 2020, that included recombinant systems in Escherichia coli cells, mam-malian and cell-free, for functional studies of Plasmodium falciparum and Plasmodium vivax antigens. 70 original articles were reviewed, 58 met the established criteria. Results: Obtaining recombinant proteins by means of a prokaryotic system, with higher performance and low cost, has allowed functional studies of a significant number of antigens. Mammalian cell and cell free systems, which allow for post-translational modifications and adequate folding of molecules, are used to produce antigen libraries with native-like conformational structure. Conclusion:Plasmodium spp. antigen study involved in infection and development in target cells, re-quires adequate selection of the recombinant production method. The refinement of expression pro-cesses in prokaryotic, eukaryotic and in vitro systems, through genetic engineering and cell culture, will allow better yields and lower cost

Introdução: Para desenvolver vacinas, é necessário entender a função dos antígenos de Plasmodium spp. envolvidos na invasão das células hospedeiras. As pesquisas têm gerado proteínas recombinan-tes utilizando sistemas de expressão heterólogos para obter moléculas similares às nativas. Com estes avanços, estratégias que bloqueiam a infecção destes patógenos estão sendo desenvolvidas. Objetivo: Descrever as características mais importantes e aspectos metodológicos dos sistemas de expressão de proteínas recombinantes em estudos funcionais de Plasmodium spp. Metodologia: Revisão descritiva dos estudos publicados em Pubmed, Science Direct, Embase e Medline, entre 2010 e 2020, que incluíram sistemas recombinantes em células de Escherichia coli, de mamífero e sistemas livres de células, para estudos funcionais dos antígenos de Plasmodium fal-ciparum e Plasmodium vivax. Setenta artigos originais foram revisados e 58 preenchiam os critérios estabelecidos. Resultado: A obtenção de proteínas recombinantes usando um sistema procariótico, com maior rendimento e baixo custo, permitiu o estudo de um número significativo de antígenos. Sistemas de células mamíferas e sem células, que permitem modificações pós-tradução e dobramento adequado das moléculas, são usados para produzir bibliotecas de antígenos com uma estrutura semelhante à nativa. Conclusão: O estudo dos antígenos Plasmodium spp. envolvidos na infecção e no desenvolvimento das células-alvo requer uma seleção adequada do método de produção recombinante. O refinamento dos processos de expressão em sistemas procarióticos, eucarióticos e in vitro, através da engenharia genética e da cultura celular, permitirá melhores rendimentos e menores custos.

Plasmodium falciparum , Plasmodium vivax , Gene Expression , Malaria , Antigens
Infectio ; 25(3): 169-175, jul.-set. 2021. tab
Article in Spanish | LILACS, COLNAL | ID: biblio-1250088


Resumen Objetivo: Verificación del desempeño de las pruebas serológicas rápidas utilizadas en el departamento de Risaralda, Colombia. Métodos: Estudio analitico, de corte transversal. Incluyó muestras de sueros de trabajadores de la salud de la ciudad de Pereira, quienes tuvieron sospecha clínica y epidemiológica por SARS-CoV-2. El procesamiento y validación de las pruebas fue realizado en las instalaciones de la Universidad Tecnológica de Pereira. Se calculó sensibilidad y especificidad de las pruebas rápidas serológicas IgM/IgG usando como prueba de oro la RT-PCR. Resultados: Se incluyeron las muestras de 144 profesionales de la salud. Las pruebas serológicas rápidas evidenciaron ser útiles para identificar o descartar la presencia de anticuerpos IgM e IgG, especialmente en pacientes sintomáticos, en quienes el inicio de los síntomas es superior a 11 días. Discusión: El uso de pruebas rápidas se encuentra en aumento, no solo por la rapidez de sus resultados, sino también por los bajos costos asociados y la necesidad de identificar pacientes no susceptibles, quienes deben priorizar su retorno a actividades laborales en comunidad como parte de la reactivación económica de Colombia. Es necesario confirmar el desempeño de la prueba para aumentar la probabilidad de una adecuada clasificación antes de proceder a su uso rutinario.

Abstract Objective: We aimed to realize a verification of the performance of the rapid serological tests used in Risaralda department. Methods: Analytical, cross-sectional study. Serum samples from health workers in Pereira city, who had a clinical and epidemiological suspicion for SARS-CoV-2 were included. The processing and validation of the tests was carried out at Universidad Tecnológica de Pereira. Sensitivity and specificity of rapid IgM / IgG sero logical tests were calculated using RT-PCR as the gold standard test. Results: 144 samples of health professionals were included. Rapid serological tests useful to identify or rule out the presence of IgM and IgG antibodies, especially in symptomatic patients, in whom the onset of symptoms is longer than 11 days. Discussion: The use of rapid tests is increasing, not only due to the speed of their results, but also due to the low associated costs and the need to identify non-susceptible patients, who must prioritize their return to work activities in the community as part of the economic reactivation of Colombia. It is necessary to confirm the adequate performance of the test to increase the probability of an adequate classification before proceeding with the routine use of this test.

Humans , Male , Female , Adult , Serologic Tests , Health Personnel , SARS-CoV-2 , Cross-Sectional Studies , COVID-19/diagnosis , Antibodies , Occupational Groups , Antigens
Rev. argent. mastología ; 40(147): 25-40, sept. 2021. graf
Article in Spanish | LILACS, BINACIS | ID: biblio-1401005


Introducción: Los tumores luminales presentan diferencias moleculares y distinto comportamiento. El antígeno ki67 (ki67) es uno de los factores que sirve para diferenciar entre luminal A y B. Las plataformas genómicas pueden identificar qué pacientes se benefician con quimioterapia. Objetivo: Establecer si existe asociación entre ki67 y Score de Oncotype Dx o score de recurrencia (SR). Evaluar la influencia del ki67 y el SR en la decisión terapéutica, evaluar la asociación entre riesgo clínico y SR, entre invasión linfovascular (ILV) y SR y entre axila positiva (hasta 1 ganglio) y SR. Material y método: Estudio retrospectivo, observacional, descriptivo. Se incluyeron 68 pacientes con tumores luminales Her2Neu negativos, T1-T2, axila negativa o positiva hasta 1 ganglio las cuales realizaron Oncotype DX entre 2009 y 2020 en el Hospital Alemán. Se clasificaron en SR menor o igual a 25 y mayor a 25 en base al estudio TAILORX donde se demostró que globalmente no hay beneficio con quimioterapia entre 0-25. Resultados: Se observó asociación entre ki67 y SR en 44 (64,7%) pacientes y fue mayor entre ki67 bajo y SR menor o igual a 25 (77,3%). El tratamiento se basó en el SR. Se observó asociación entre riesgo clínico y SR en 43 (63,2%) pacientes y fue mayor entre bajo riesgo clínico y SR menor o igual a 25 (87,5%). En un 88,8% no existió asociación entre ILV y SR, como así tampoco, entre axila positiva hasta 1 ganglio y SR en un 85,7%. Conclusiones: Es menester ofrecer a toda paciente con un tumor luminal una plataforma genómica ya que tanto el ki67 como otros factores clínicopatológicos por sí solos no demostraron ser superiores ni suficientes.

Introduction: Luminal tumors show molecular differences and different behavior. The antigen ki67 (ki67) is one of the factors that differentiate between luminal A and B. Genomic platforms can identify which patients will benefit from chemotherapy. Objective: To establish if there is an association between ki67 and Oncotype Dx Score or recurrence score (RS). To assess the influence of ki67 and RS on the therapeutic decision, to evaluate the association between clinical risk and RS, between lymphovascular invasion (LVI) and RS, and between positive armpit (up to 1 node) and RS. Material and method: Retrospective, observational, descriptive study. We included 68 patients with negative Her2Neu luminal tumors, T1-T2, negative or positive axillary up to 1 node, who performed Oncotype DX between 2009 and 2020 at Hospital Alemán. They were classified into RS less than or equal to 25 and greater than 25 based on the TAILORX study, where it was shown that overall there is no benefit from chemothe- rapy between 0-25. Results: An association was observed between ki67 and RS in 44 (64.7%) patients and it was greater between low ki67 and RS less than or equal to 25 (77.3%). The treatment was based on RS. An association between clinical risk and RS was observed in 43 (63.2%) patients, and it was greater between low clinical risk and RS less than or equal to 25 (87.5%). In 88.8% there was no association between LVI and RS, as well as between positive axillary up to 1 node and RS in 85.7%. Conclusions: It is necessary to offer every patient with a luminal tumor a genomic platform since both ki67 and other clinicopathological factors alone did not prove to be superior or sufficient.

Female , Breast Neoplasms , Therapeutics , Ki-67 Antigen , Drug Therapy , Antigens
Goiânia; SES-GO; 31 ago 2021. 1-9 p. ilus.
Non-conventional in Portuguese | LILACS, ColecionaSUS, CONASS, SES-GO | ID: biblio-1290834


Em janeiro de 2020, os testes para detectar o SARS-CoV-2 em amostras coletadas de pacientes foram desenvolvidos logo após o sequenciamento e divulgação do genoma do vírus (CORMAN et al., 2020) e, desde então, diferentes metodologias de testagem , têm sido empregadas em contextos distintos. Embora sejam o padrão de referência para diagnóstico da infecção aguda pelo SARS-CoV-2, os testes moleculares de reação em cadeia da polimerase (RT-PCR) não podem ser dimensionados para atender às demandas extensas da saúde pública (MINA & ANDERSEN, 2021). O processo é limitado para algumas regiões devido à necessidade de equipamentos sofisticados, operadores extremamente qualificados ao tempo que pode decorrer. Contudo, os testes de antígeno, permitem limitar de forma eficaz a disseminação da COVID-19 e responder a surtos da pandemia. Foram levantadas no estudo as recomendações quanto aos testes de antígeno emitidos pela Organização Mundial da Saúde (OMS), pela Europa, pelo Reino Unido, Estados Unidos, Israel e Brasil.

In January 2020, tests to detect SARS-CoV-2 in samples collected from patients were developed soon after the sequencing and dissemination of the virus genome (CORMAN et al., 2020) and, since then, different testing methodologies, have been used in different contexts. Although they are the reference standard for diagnosing acute SARS-CoV-2 infection, molecular polymerase chain reaction (RT-PCR) tests cannot be scaled to meet the extensive demands of public health (MINA & ANDERSEN, 2021 ). The process is limited to some regions due to the need for sophisticated equipment, extremely qualified operators and the time that may elapse. However, antigen tests effectively limit the spread of COVID-19 and respond to pandemic outbreaks. Recommendations for antigen tests issued by the World Health Organization (WHO), Europe, the United Kingdom, the United States, Israel and Brazil were raised in the study.

Humans , Male , Female , Pregnancy , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , COVID-19/prevention & control , Antigens/administration & dosage
Rev. panam. salud pública ; 45: e87, 2021. tab, graf
Article in Portuguese | LILACS | ID: biblio-1289871


RESUMO O Plano Global de Eliminação da Filariose Linfática, lançado pela Organização Mundial da Saúde em 2000, propõe o uso de testes de detecção de antígeno circulante filarial como ferramenta diagnóstica para avaliação e monitoramento das ações de controle da parasitose. Entretanto, esses testes, apesar de apresentarem alta sensibilidade, não conseguem detectar com eficiência a infecção em seu estágio inicial, quando ainda não existe a presença de helmintos adultos. Considerando essa limitação, a pesquisa de anticorpos antifilariais tem sido apontada como uma alternativa, uma vez que os anticorpos produzidos contra as larvas infectantes do parasito são detectados antes da presença de antígeno circulante filarial. O objetivo deste estudo foi definir o ponto de corte e avaliar a acurácia do kit Filaria Detect™ IgG4 produzido com o antígeno recombinante Wb123 para diagnóstico da filariose linfática no Brasil. Para isso, foi realizado um estudo de avaliação de teste diagnóstico, no qual foram utilizadas 256 amostras de soro: 79 (30,9%) obtidas de indivíduos microfilarêmicos e 177 (60,1%), de indivíduos amicrofilarêmicos e que testaram negativo para os testes imunológicos Bm14 CELISA e Og4C3 ELISA. A definição do ponto de corte ideal, bem como da acurácia do kit Filaria Detect™ IgG4, foi obtida através da construção de curvas ROC, sendo a densidade óptica de 0,239 aquela na qual o teste obteve melhor desempenho, com sensibilidade de 81,0% e especificidade de 96,6%. Os resultados obtidos demonstraram que o kit Filaria Detect™ IgG4 é uma ferramenta promissora para investigação e monitoramento de áreas submetidas ao tratamento em massa para filariose linfática.

ABSTRACT The Global Programme to Eliminate Lymphatic Filariasis, launched by the World Health Organization in the year 2000, proposes the use of circulating filarial antigen tests as a diagnostic tool to assess and monitor initiatives to control filarial infection. However, despite a high sensitivity, these tests are not efficient to detect infection at early stages, before worms have reached the adult stage. Considering this limitation, anti-filarial antibody testing has been suggested as an alternative, given that the antibodies produced against the larvae are detectable before the presence of circulating filarial antigen. The objective of the present study was to determine the diagnostic cut-off and the accuracy of the Filaria Detect™ IgG4 kit employing recombinant Wb123 antigen for diagnosis of lymphatic filariasis in Brazil. For that, we performed a diagnostic evaluation study in which 256 serum samples were analyzed: 79 (30.9%) obtained from microfilaremic individuals and 177 (60.1%) from amicrofilaremic individuals who tested negative with the Bm14 CELISA and Og4C3 ELISA immunologic tests. The ideal cutoff as well as the Filaria Detect™ IgG4 kit accuracy were determined based on ROC curve analyses, with an optical density of 0.239 identified as the cutoff with the best performance, with 81.0% sensitivity and 96.6% specificity. The results show that the Filaria Detect™ IgG4 kit is a promising tool for investigation and monitoring of areas undergoing mass drug administration for lymphatic filariasis.

RESUMEN En el programa mundial de eliminación de la filariasis linfática, puesto en marcha por la Organización Mundial de la Salud en el año 2000, se propone el uso de pruebas de detección del antígeno filárico circulante como instrumento de diagnóstico para la evaluación y el seguimiento de las medidas de control de la parasitosis. Sin embargo, esas pruebas, a pesar de tener un alto grado de sensibilidad, no permiten detectar con eficiencia la infección en su fase inicial, cuando todavía no existen helmintos adultos. En vista de esa limitación, se ha señalado como una opción el estudio de anticuerpos antifiláricos, puesto que los anticuerpos producidos contra las larvas infectantes del parásito se detectan antes de la existencia de antígeno filárico circulante. El objetivo de este estudio fue definir el punto de corte y evaluar la exactitud del estuche Detect™ para pruebas de anticuerpos antifiláricos IgG4, fabricado con el antígeno recombinante Wb123, para el diagnóstico de la filariasis linfática en Brasil. Para ello, se realizó un estudio de evaluación de la prueba diagnóstica, en el cual se utilizaron 256 muestras de suero, a saber, 79 (30,9%) obtenidas de personas microfilarémicas y 177 (60,1%) de personas amicrofilarémicas, que arrojaron resultados seronegativos en las pruebas inmunológicas CELISA Bm14 y ELISA Og4C3. La definición del punto de corte ideal y de la exactitud del estuche Detect™ se obtuvo con la construcción de curvas de la característica operativa del receptor (ROC); una densidad óptica de 0,239 marcó el mejor nivel de desempeño de la prueba, con una sensibilidad de 81,0% y una especificidad de 96,6%. Los resultados obtenidos demostraron que el estuche Detect™ es un instrumento prometedor para la investigación y el seguimiento de las regiones donde se realiza un tratamiento masivo de la filariasis linfática.

Humans , Reagent Kits, Diagnostic , Elephantiasis, Filarial/diagnosis , Immunoglobulin G/immunology , Antigens/immunology , Brazil , Predictive Value of Tests , Reproducibility of Results , ROC Curve , Sensitivity and Specificity
São Paulo; s.n; s.n; 2021. 108 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1396837


O Plasmodium vivax é a espécie mais comum de parasita causador da malária humana encontrada fora da África, com maior endemicidade na Ásia, América Central e do Sul e Oceania. Embora o Plasmodium falciparum cause a maioria do número de mortes, o P. vivax pode levar à malária grave e resultar em morbimortalidade significativa. O desenvolvimento de uma vacina protetora será um passo importante para a eliminação da malária. Recentemente, uma formulação contendo as três variantes alélicas da proteína circumsporozoíta de P. vivax (PvCSP - All epitopes) induziu proteção parcial em camundongos após desafio com esporozoíto híbrido Plasmodium berghei (Pb), no qual as repetições centrais do PbCSP foram substituídas por repetições PvCSP-VK210 (esporozoítos Pb/Pv). No presente estudo, a proteína quimérica PvCSP contendo as variantes alélicas (VK210, VK247 e P. vivax-like) fusionadas com a proteína de nucleocapsídeo do vírus da caxumba (formando partículas semelhantes a nucleocapsídeos ou do inglês, NLP - Núcleo Like Particles) na ausência (NLP-CSPR) ou na presença do domínio C-terminal (CT) conservado da PvCSP (NLP-CSPCT). Para a realização do estudo selecionamos os adjuvantes Poly (I:C), um RNA sintético de dupla fita, agonista do receptor Toll do tipo 3 (TLR3) ou o adjuvante Montanide ISA 720, uma emulação óleo em agua. Para obter uma forte resposta imune, a levedura Pichia pastoris foi usada para expressar as proteínas recombinantes na forma de NLPs. Camundongos foram imunizados com cada uma das proteínas recombinantes em combinação com os adjuvantes citados. Embora ambas as NLPs tenham sido capazes de gerar uma forte resposta imune, com altos níveis de títulos e longevidade, apenas a formulação contendo a proteína NLP-CSPCT na presença do adjuvante Poly (I:C) foi selecionada para ser explorada em experimentos futuros. Esta proteína em combinação com o adjuvante Poly (I:C) induziu alta frequência de células secretoras de anticorpos específicas para o antígeno homólogo nos dias 5 e 30, no baço e na medula óssea, respectivamente. Altos títulos de IgG contra as 3 variantes de PvCSP foram detectados nos soros. Posteriormente camundongos imunizados com NLP-CSPCT foram desafiados com esporozoítos Pb/Pv e a parasitemia no 5º dia demonstrou proteção estéril em 30% dos camundongos desafiados. Portanto, a formulação vacinal gerada neste estudo tem potencial para ser explorada no desenvolvimento de uma vacina universal contra a malária causada por P. vivax

Plasmodium vivax is the most common species of human malaria parasite found outside Africa, with high endemicity in Asia, Central and South America, and Oceania. Although Plasmodium falciparum causes the majority of deaths, P. vivax can lead to severe malaria and result in significant morbidity and mortality. The development of a protective vaccine will be a major step toward malaria elimination. Recently, a formulation containing the three allelic variants of the P. vivax circumsporozoite protein (PvCSP--All epitopes) showed partial protection in mice after a challenge with the hybrid Plasmodium berghei (Pb) sporozoite, in which the PbCSP central repeats were replaced by the VK210 PvCSP repeats (Pb/Pv sporozoite). In the present study, the chimeric PvCSP allelic variants (VK210, VK247, and P. vivax-like) were fused with the mumps virus nucleocapsid protein (assembling into nucleo like particles - NLP) in the absence (NLP-CSPR) or presence of the conserved C-terminal (CT) domain of PvCSP (NLP-CSPCT). To carry out the study, we selected the adjuvants Poly (I:C), a synthetic double-stranded RNA, Toll-like receptor 3 (TLR3) agonist or Montanide ISA 720 adjuvant, an oil-water emulation. To elicit stronger immune response, Pichia pastoris yeast was used to produce the NLPs. Mice were immunized with each recombinant protein in combination with above. Although both NLPs were able to generate stronger immune response, with high antibodies titer levels and longevity, formulation containing NLP-CSPCT in the presence of Poly (I:C) was selected to be explored in future experiments. NLP-CSPCT with Poly (I:C) adjuvant presented a high frequency of antigen-specific antibody-secreting cells (ASCs) on days 5 and 30, respectively, in the spleen and bone marrow. Moreover, high IgG titers against all PvCSP variants were detected in the sera. Later, immunized mice with NLP-CSPCT were challenged with Pb/Pv sporozoites. Sterile protection was observed in 30% of the challenged mice. Therefore, this vaccine formulation use has the potential to be a good candidate for the development of a universal vaccine against P. vivax malaria.

Animals , Female , Mice , Plasmodium vivax/classification , Vaccines, Virus-Like Particle/analysis , RNA, Double-Stranded , Malaria, Vivax/pathology , Malaria Vaccines , Toll-Like Receptor 3 , Malaria/pathology , Antibody-Producing Cells/classification , Antigens/adverse effects
Chinese Journal of Biotechnology ; (12): 2293-2306, 2021.
Article in Chinese | WPRIM | ID: wpr-887797


Mouse hybridoma monoclonal antibody is the most commonly used antibody in immunology because of its stable source, easy preparation in later stage and high yield. The traditional time-consuming and laborious hybridoma preparation technology could not meet the growing market demand. In this paper, we describe the rapid preparation techniques involved in antigen design and screening, B cell enrichment and screening, transgenic myeloma cells, fusion technology improvement, positive hybridoma cell screening and rapid detection of monoclonal antibody performance, to provide a reference for rapid preparation of mouse hybridoma monoclonal antibody.

Animals , Antibodies, Monoclonal , Antigens , B-Lymphocytes , Hybridomas , Mice
Braz. arch. biol. technol ; 64(spe): e21210127, 2021. tab, graf
Article in English | LILACS | ID: biblio-1285571


Abstract The rapid and accurate diagnosis of tuberculosis (TB), especially considering limited resources, is still a challenge. Development of new methodologies and tests are needed to overcome several disadvantages of the available standard tests. We evaluated the diagnostic potential of two antigens specific for Mycobacterium tuberculosis, the CFP10 and ESAT6 recombinant proteins, and developed stable formulations thereof. Sensitivity and specificity of the delayed-type hypersensitivity (DTH) skin testing and the induction of gamma interferon production (IFN-γ) by lymphocytes, as a non-invasive test, were evaluated using the CFP10 and ESAT6 protein formulations. The recombinant proteins produced by our group presented a high DTH response and the ability to differentiate between tuberculosis infection, BCG vaccination, and the contact with non-tuberculous mycobacteria (NTM). The production of IFN-γ by stimulation with individual and combined proteins was detected in a panel of 40 individuals and showed a specificity of 100% and a sensitivity of 90% when the two proteins were used together. Lyophilized formulations were stable under all conditions, while soluble formulations were stable under freezing at -20 ºC and -80 ºC. The proposed formulations containing the ESAT6 and CFP10 recombinant antigens constitute satisfactory tools for TB testing, suitable to be developed and implemented in a large-scale trial.

Tuberculosis/diagnosis , Interferon-gamma , Mycobacterium tuberculosis/isolation & purification , Antigens/chemistry
Rio de Janeiro; s.n; 2021. 117 p. ilus.
Thesis in Portuguese | LILACS | ID: biblio-1349190


Introdução: Os testes rápidos para diagnóstico de malária (RDTs) mais usados se baseiam na identificação do antígeno HRP2 de P. falciparum. O antígeno HRP3, também presente no P. falciparum é um análogo estrutural do antígeno HRP2 e por isso pode ter reação cruzada com o HRP2 nesses testes. O antígeno HRP2 é expresso pelo gene pfhrp2, enquanto o antígeno HRP3 é expresso pelo gene pfhrp3. São crescentes os estudos que relatam deleções naturais dos genes pfhrp2 e pfhrp3 em P. falciparum em diversos países endêmicos para malária, inclusive em países que fazem fronteira com o Brasil. No país foi descrita a presença de isolados mutantes circulando na região da Bacia do Rio Amazonas. A confirmação da presença de parasitos com essas deleções em áreas endêmicas do país é fundamental, visto que indivíduos infectados por P. falciparum com deleção dos genes pfhrp2/3 podem apresentar resultados falso negativo no RDT. O objetivo deste estudo foi investigar a prevalência de deleções dos genes pfhrp2/3 em amostras de pacientes infectados com P. falciparum de área endêmica de malária no Brasil no período de 2003 a 2016, e bem como identificar a população acometida e a diferenciação clínica entre indivíduos infectados por parasitos com deleção e parasitos sem deleção. Métodos: Foram analisadas amostras procedentes do biorrepositório do Laboratório de Doenças Parasitárias do Instituto Oswaldo Cruz coletadas no período de 2003 a 2016 no município de Barcelos (AM) de indivíduos sintomáticos e assintomáticos infectados por P. falciparum. O diagnóstico de Plasmodium spp. foi realizado através da detecção do gene 18S de rRNA por PCR. O controle de qualidade do DNA foi realizado pela amplificação de msp1 e msp2. A detecção dos genes pfhrp2 e pfhrp3 foi realizada de acordo com protocolos publicados e bem padronizados pela OMS. Resultados: Foram selecionadas 82 amostras, 28 amostras apresentaram deleção exclusiva do gene pfhrp2, 19, deleção exclusiva do gene pfhrp3 e 15 dupla deleção. Infecção assintomática ocorreu com mais frequência em indivíduos mais velhos e com grande número episódios prévios da doença. A chance de um indivíduo assintomático estar infectado por um parasito com dupla deleção foi maior do que entre os sintomáticos. Conclusão: A alta prevalência de parasitos com deleções de pfhrp2/3 encontrada no município de Barcelos é motivo de preocupação e mostram a necessidade de se implementar um programa de vigilância para monitorar e mapear deleções de pfhrp2/3 nesta área e em outros locais da região amazônica. O padrão clínico pode estar associado às deleções encontradas nos parasitos infectantes.

Introduction: The most used rapid tests for the diagnosis of malaria are based on the identification of the P. falciparum antigen HRP2. The HRP3 antigen, also present in P. falciparum, is a structural analogue of the HRP2 antigen and, therefore, may cross-react with HRP2 in these tests. The HRP2 antigen is expressed by the pfhrp2 gene, while the HRP3 antigen is expressed by the pfhrp3 gene. Studies reporting natural deletions of the pfhrp2 and pfhrp3 genes in P. falciparum are growing in several countries endemic for malaria, including countries bordering Brazil. In the country, the presence of mutant isolates circulating in the Amazon River Basin region has been described. Confirmation of the presence of parasites with these deletions in other endemic areas of the country is fundamental, since individuals infected with P. falciparum with deletion of the pfhrp2/3 genes can present false negative result in the RDT. The objective of this study was to investigate the deletions of the pfhrp2/3 genes in samples from patients infected with P. falciparum in an endemic area for malaria in Brazil from 2003 to 2016, in order to describe the prevalence of the gene (s) ( s) deleted in the studied endemic area; as well as to identify the affected population and the clinical differentiation between individuals infected by parasites with deletion and parasites without deletion. Methods: Samples from the biorepository of the Laboratory of Parasitic Diseases of the Oswaldo Cruz Institute collected from 2003 to 2016 in the municipality of Barcelos (AM) from symptomatic and asymptomatic individuals infected with P. falciparum were analyzed. The diagnosis of Plasmodium spp. was performed by detecting the 18S rRNA gene by PCR. DNA quality control was performed by amplifying msp1 and msp2. The detection of the pfhrp2 and pfhrp3 genes was carried out according to published protocols and well standardized by the WHO. Results: 82 samples were selected, 28 samples showed exclusive deletion of the pfhrp2 gene, 19, exclusive deletion of the pfhrp3 gene and 15 double deletion. Asymptomatic infection occurred more frequently in older individuals and with a large number of previous episodes of the disease. The chance of an asymptomatic individual being infected by a parasite with double deletion was greater than among symptomatic individuals. Conclusion: The high prevalence of parasites with deletions of fhrp2/3 found in the municipality of Barcelos is a cause for concern and shows the need to implement a surveillance program to monitor and map deletions of pfhrp2 / 3 in this area and elsewhere in the Amazon region. The clinical pattern may be associated with the deletions found in the infectious parasites.

Parasitic Diseases , Plasmodium falciparum , Prevalence , Genes , Malaria , Antigens
Mem. Inst. Oswaldo Cruz ; 116: e200560, 2021. graf
Article in English | LILACS | ID: biblio-1154882


BACKGROUND Anisakis simplex antigens present immunomodulatory properties by the induction of tolerogenic dendritic cells (DCs) in mice. OBJECTIVES To study the capacity of DCs stimulated with A. simplex excretory-secretory (ES) or crude extract (CE) to generate Tregs. To investigate in vitro effects of antigens on the metabolic activity of splenocytes induced by LPS or CpG. METHODS Phenotypic and functional characterization of T cells co-cultured with A. simplex-pulsed DCs was performed by flow cytometry. Lymphocyte mitochondrial respiratory activity was estimated by the Alamar Blue® Assay. FINDINGS In C57BL/6J, CD4+CD25-Foxp3+ and CD8+CD25-Foxp3+ populations increased by CE-stimulated-DCs. In BALB/c, CE-stimulated-DCs caused the expansion of CD4+CD25+Foxp3+IL-10+ and CD8+CD25+Foxp3+IL-10+. IFN-γ expression raised in BALB/c CD4+CD25+ and CD4+CD25- for CE and ES, respectively. ES-stimulated-DCs increased CD4+CD25+ Foxp3+ and CD8+CD25- Foxp3+ expression in T cells. The association of ES or CE with LPS produced the increase in splenocyte activity in C57BL/6J. The association of CE with CpG decreased the proliferation caused by CpG in C57BL/6J. MAIN CONCLUSIONS A. simplex increase the frequency of Tregs, which in turn produce IL-10 and IFN-γ. The host genetic base is essential in the development of anti-Anisakis immune responses (Th2, Th1, Treg).

Animals , Mice , Anisakis , T-Lymphocytes, Regulatory , Antigens/metabolism , Bone Marrow , Dendritic Cells , Forkhead Transcription Factors , Interleukin-2 Receptor alpha Subunit , Larva , Mice, Inbred BALB C , Mice, Inbred C57BL
Rev. Méd. Clín. Condes ; 31(3/4): 256-269, mayo.-ago. 2020. ilus, tab
Article in Spanish | LILACS | ID: biblio-1223737


Las vacunas son altamente efectivas en prevenir enfermedades infecciosas a través del desarrollo en el individuo de una respuesta inmune protectora, sin desarrollar la enfermedad. Los distintos tipos de vacunas producen diferentes tipos de respuestas inmunes y variadas estrategias se han desarrollado para mejorar esta respuesta. El sistema inmune sufre cambios con la edad y esta inmunosenecencia altera la capacidad de responder frente a ellas. Por otro lado, si bien el sistema inmune puede reconocer elementos presentes en las vacunas y montar respuestas de hipersensibilidad ante ellos, las alergias a las vacunas son raras, teniendo que distinguirlas adecuadamente de otro tipo de reacciones. En caso que un paciente presente una reacción compatible con alergia, es importante conocer todos los componentes de la vacuna para realizar un estudio adecuado.

Vaccines are highly effective in preventing infectious diseases through the development in the individual a protective immune response, without developing the disease. Different types of vaccines produce different types of immune responses, and varied strategies have been developed to improve this response. The immune system undergoes changes with age, and this inmunosenescence alters the ability to respond to them. On the other hand, although the immune system can recognize elements present in vaccines and establish hypersensitivity responses to them, vaccine allergies are rare, having to properly distinguish them from other types of reactions. In the event that a patient has an allergy-compatible reaction, it is important to know all the components of the vaccine to conduct a proper study.

Humans , Vaccines/adverse effects , Vaccines/immunology , Immunization/adverse effects , Hypersensitivity/immunology , Immunity/immunology , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/immunology , Vaccines, Inactivated/adverse effects , Vaccines, Inactivated/immunology , Immunosenescence , Anaphylaxis/immunology , Antigens/immunology
Acta bioquím. clín. latinoam ; 54(4): 407-414, jul. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1149030


Resumen La identificación inequívoca del antígeno D en medicina transfusional es de vital importancia para evitar reacciones postransfusionales y la enfermedad hemolítica del recién nacido. Es común el uso de reactivos serológicos monoclonales o tarjetas de gel y su interpretación está definida por cruces, de acuerdo con la reacción serológica. El propósito de este estudio fue determinar la frecuencia del factor Rh y las variantes del antígeno D en una población afroecuatoriana. Se trató de un estudio descriptivo, transversal con muestreo aleatorio simple de 541 pobladores. Para la tipificación del factor Rh se utilizó la metodología en tubo con antisueros monoclonales y para la detección de las variantes de D se utilizaron tarjetas de gel IDCoombs Anti-IgG. Las lecturas se verificaron mediante el análisis del índice kappa. Se aplicó estadística descriptiva y el análisis de Chi cuadrado para establecer la relación de las variables y su significación. Se identificó una frecuencia del 92% de individuos Rh(D) positivo y un 8% Rh(D) negativo. El 4,80% de los individuos presentaban la variante D débil y el 79% reacciones serológicas entre 2 y 3(+) indicativas de otras variantes del antígeno D. El fenotipo más común fue el R0/R0. Estos datos demuestran la necesidad de confirmar la existencia de variantes del antígeno D en esta población para un mejor manejo de la sangre. Una limitante constituye la disponibilidad de técnicas moleculares para la genotipificación de D; sin embargo, se podría implementar la fenotipificación RHCE como estrategia pretransfusional.

Abstract The unequivocal identification of D antigen in transfusion medicine is of vital importance to avoid post-transfusion reactions and hemolytic disease of the newborn. The use of monoclonal serological reagents or gel cards is common and their interpretation is defined according to the serological reaction by crosses. The purpose of this study was to determine the frequency of Rh factor and D antigen variants in the Afro-Ecuadorian population. This was a descriptive, cross-sectional study with simple random sampling of 541 residents. Tube typing with monoclonal antisera was used to typify Rh factor and ID-Coombs Anti-IgG gel cards were used to detect D variants, and the readings were verified by analysis of the kappa index. Descriptive statistics and Chi-square analysis were applied for the relationship of the variables and their significance. A frequency of 92% of Rh(D) positive individuals and 8% Rh(D) negative individuals were identified. Almost 5% (4.80%) of the individuals presented the weak D variant and 79% serological reactions between 2-3(+) indicative of other D antigen variants, the most common phenotype being R0/R0. These data demonstrate the need to confirm the existence of D antigen variants in this population for better management and availability of blood. A limitation is the availability of molecular techniques for D genotyping, however, RHCE phenotyping could be implemented as a pretransfusion strategy.

Resumo A identificação inequívoca do antígeno D na medicina transfusional é de vital importância para evitar reações pós-transfusionais e a doença hemolítica do recém-nascido. É comum o uso de reagentes sorológicos monoclonais ou cartões de gel e sua interpretação é definida por cruzamentos de acordo com a reação sorológica. O objetivo deste estudo foi determinar a frequência do fator Rh e as variantes do antígeno D numa população afro-equatoriana. Foi um estudo descritivo, transversal, com amostragem aleatória simples de 541 residentes. Para a tipagem do fator Rh foi utilizada a metodologia em tubo com anti-soros monoclonais e para a detecção das variantes de D, os cartões de gel ID-Coombs Anti-IgG. As leituras foram verificadas por análise do índice kappa. Foi aplicada estatística descritiva e para estabelecer a relação das variáveis e sua significação se utilizou a análise do qui-quadrado. Identificando uma frequência de 92% dos indivíduos Rh (D) positivos e 8% Rh (D) negativos. 4,80% dos indivíduos apresentavam a variante D fraca e 79% reações sorológicas entre 2 e 3(+) indicativas de outras variantes do antígeno D, sendo o fenótipo mais comum o R0/R0. Esses dados demonstram a necessidade de confirmar a existência de variantes do antígeno D nessa população para melhor gerenciamento e disponibilidade de sangue. Uma limitação é a disponibilidade de técnicas moleculares para a genotipagem de D, no entanto, a fenotipagem de RHCE poderia ser implementada como uma estratégia de pré-transfusão.

Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Rh-Hr Blood-Group System/analysis , Rh-Hr Blood-Group System/blood , Antigens/analysis , Population , Rh-Hr Blood-Group System , Blood , Infant, Newborn , Cross-Sectional Studies , Transfusion Medicine , Indicators and Reagents , Infant, Newborn, Diseases/prevention & control , Antigens