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1.
Vaccimonitor (La Habana, Print) ; 30(2)mayo.-ago. 2021. tab, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1252325

ABSTRACT

El uso de anticuerpos monoclonales en la lucha contra el cáncer se convierte cada día más en la terapia de elección. Para la introducción de anticuerpos monoclonales en mercados internacionales de alta demanda y con elevados requerimientos de calidad se requiere su producción a gran escala. El incremento de la presencia de dímeros en el producto final afecta su calidad y, por tanto, la eficiencia y eficacia del proceso. El objetivo del presente trabajo fue obtener un modelo matemático que permita relacionar el porcentaje de dímeros con las variables de operación de mayor influencia. Se realizó el ajuste de un modelo de regresión lineal múltiple usando el programa Statgraphics Centurion XVII versión 17.2.00. El modelo se validó con lotes de producción, logrando errores relativos inferiores al 20 por ciento. Las variables significativas obtenidas fueron: masa de IgG en el sobrenadante; masa de IgG en el producto de salida del paso de captura de proteína A; pH en el producto de salida del paso de captura de proteína A; pH del producto ajustado y conductividad de salida en la membrana de intercambio aniónico. El modelo permitió encontrar un intervalo de trabajo de las variables de mayor influencia en la formación de dímeros para reducirlos hasta valores inferiores al 3 por ciento(AU)


The use of monoclonal antibodies in the fight against cancer is becoming more and more the selected therapy. The introduction of monoclonal antibodies highly demanded in international markets, with high quality requirements needs the production of monoclonal antibodies on a large scale. The increase of dimers in the final product affects its quality, therefore, the efficiency and effectiveness of the process. The objective of this work was to obtain a mathematical model to relate the percentage of dimers with the most influential operating variables. A multiple linear regression model was obtained using Statgraphics Centurion XVII version 17.2.00 software. The model was validated with new production data with a mean error of validation below 20 percent. The significant variables were: supernatant IgG mass; IgG mass in the effluent from Protein A capture column; pH of the effluent from Protein A capture column; pH of the adjusted product and conductivity of the effluent from anionic exchange membrane. A working interval for each of the influential variables were established, in order to reduce dimers below 3 percent(AU)


Subject(s)
Humans , Mathematical Computing , Data Analysis , Antibodies, Monoclonal/immunology , Neoplasms/mortality , Cuba
2.
Electron. j. biotechnol ; 44: 6-13, Mar. 2020. tab, graf, ilus
Article in English | LILACS | ID: biblio-1087627

ABSTRACT

BACKGROUND: Hot start can greatly improve specificity, sensitivity and yield of PCR. Non-specific amplification can occur in PCR when reaction mixture is prepared at room temperature, because Taq DNA polymerase is active and the primers can hybridize non-specifically. Hot start Taq DNA polymerases remain inactive at room temperature and are activated after heating at 95°C preventing non-specific amplification. Monoclonal antibodies against Taq DNA polymerase is the first line of reagents used for turn on regular Taq DNA polymerase into Hot start one. The goal of this research was to produce and evaluate Hot Start antibodies derived from chicken eggs. RESULTS: We performed affinity purification of yolk immunoglobulin (IgY) and obtained polyclonal Hot Start antibodies. The yield of specific antibodies was 0.36 mg per egg or 0.2% of total yolk antibodies. The protocol for real time measurement and Hot start IgY activity assessment was developed. We found that Hot start IgY can reversibly block Taq DNA polymerase activity at 50°C and have no negative impact neither on the Taq DNA polymerase activity after denaturation nor on the reverse transcriptase. We estimated that 1.0 µg of Hot start IgY effectively blocks 5 U activity of Taq DNA polymerase. CONCLUSIONS: Egg derived Hot Start polyclonal antibodies are the cheapest source of Hot start antibodies, from one immune egg we can isolate 0.36 mg IgY, this quantity is enough for producing 1800 U activity of Hot start Taq DNA Polymerase.


Subject(s)
Egg Yolk/metabolism , Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/immunology , Temperature , Immunoglobulins/isolation & purification , Immunoglobulins/biosynthesis , Immunoglobulins/immunology , Enzyme-Linked Immunosorbent Assay , Polymerase Chain Reaction , Taq Polymerase , Egg Yolk/immunology , Antibodies, Monoclonal/isolation & purification
3.
Braz. j. med. biol. res ; 53(2): e8917, 2020. graf
Article in English | LILACS | ID: biblio-1055492

ABSTRACT

This study investigates the effect of the overexpression of the placental growth factor (PGF) and hyperoxia on lung development and determines whether anti-PGF antibody ameliorates hyperoxia-mediated impairment of lung development in newborn rats. After exposure to normoxic conditions for seven days, newborn rats subjected to normoxia were intraperitoneally or intratracheally injected with physiological saline, adenovirus-negative control (Ad-NC), or adenovirus-PGF (Ad-PGF) to create the Normoxia, Normoxia+Ad-NC, and Normoxia+Ad-PGF groups, respectively. Newborn rats subjected to hyperoxia were intraperitoneally injected with physiological saline or anti-PGF antibodies to create the Hyperoxia and Hyperoxia+anti-PGF groups, respectively. Our results revealed significant augmentation in the levels of PGF and its receptor Flt-1 in the lung tissues of newborn rats belonging to the Normoxia+Ad-PGF or Hyperoxia groups. PGF overexpression in these groups caused lung injury in newborn rats, while anti-PGF antibody treatment significantly cured the hyperoxia-induced lung injury. Moreover, PGF overexpression significantly increased TNF-α and Il-6 levels in the bronchoalveolar lavage (BAL) fluid of the Normoxia+Ad-PGF and Hyperoxia groups. However, their levels were significantly reduced in the BAL fluid of the Hyperoxia+anti-PGF group. Immunohistochemical analysis revealed that PGF overexpression and hyperoxia treatment significantly increased the expression of the angiogenesis marker, CD34. However, its expression was significantly decreased upon administration of anti-PGF antibodies (compared to the control group under hyperoxia). In conclusion, PGF overexpression impairs lung development in newborn rats while its inhibition using an anti-PGF antibody ameliorates the same. These results provided new insights for the clinical management of bronchopulmonary dysplasia in premature infants.


Subject(s)
Animals , Female , Pregnancy , Rats , Autoantibodies/metabolism , Hyperoxia/metabolism , Lung Injury/metabolism , Placenta Growth Factor/metabolism , Antibodies, Monoclonal/metabolism , Autoantibodies/immunology , Microscopy, Electron, Scanning , Hyperoxia/complications , Hyperoxia/diagnostic imaging , Disease Models, Animal , Lung Injury/pathology , Lung Injury/diagnostic imaging , Placenta Growth Factor/immunology , Animals, Newborn , Antibodies, Monoclonal/immunology
4.
J. bras. pneumol ; 42(3): 203-210, tab, graf
Article in English | LILACS | ID: lil-787489

ABSTRACT

ABSTRACT Objective: Ventilator-associated pneumonia (VAP) is the leading type of hospital-acquired infection in ICU patients. The diagnosis of VAP is challenging, mostly due to limitations of the diagnostic methods available. The aim of this study was to determine whether antibody-coated bacteria (ACB) evaluation can improve the specificity of endotracheal aspirate (EA) culture in VAP diagnosis. Methods: We conducted a diagnostic case-control study, enrolling 45 patients undergoing mechanical ventilation. Samples of EA were obtained from patients with and without VAP (cases and controls, respectively), and we assessed the number of bacteria coated with FITC-conjugated monoclonal antibodies (IgA, IgM, or IgG) or an FITC-conjugated polyvalent antibody. Using immunofluorescence microscopy, we determined the proportion of ACB among a fixed number of 80 bacteria. Results: The median proportions of ACB were significantly higher among the cases (n = 22) than among the controls (n = 23)-IgA (60.6% vs. 22.5%), IgM (42.5% vs. 12.5%), IgG (50.6% vs. 17.5%), and polyvalent (75.6% vs. 33.8%)-p < 0.001 for all. The accuracy of the best cut-off points for VAP diagnosis regarding monoclonal and polyvalent ACBs was greater than 95.0% and 93.3%, respectively. Conclusions: The numbers of ACB in EA samples were higher among cases than among controls. Our findings indicate that evaluating ACB in EA is a promising tool to improve the specificity of VAP diagnosis. The technique could be cost-effective and therefore useful in low-resource settings, with the advantages of minimizing false-positive results and avoiding overtreatment.


RESUMO Objetivo: A pneumonia associada à ventilação mecânica (PAVM) é o principal tipo de infecção adquirida no ambiente hospitalar em pacientes em UTIs. O diagnóstico de PAVM é desafiador, principalmente devido a limitações dos métodos diagnósticos disponíveis. O objetivo deste estudo foi determinar se a avaliação de bactérias revestidas por anticorpos (BRA) pode melhorar a especificidade de culturas de aspirado traqueal (AT) no diagnóstico de PAVM. Métodos: Estudo diagnóstico caso-controle envolvendo 45 pacientes sob ventilação mecânica. Amostras de AT foram obtidas de pacientes com e sem PAVM (casos e controles, respectivamente), e verificamos o número de bactérias revestidas com anticorpos monoclonais conjugados com FITC (IgA, IgM ou IgG) ou anticorpo polivalente conjugado com FITC. Utilizando microscopia de imunofluorescência, foi determinada a proporção de BRA em um número fixo de 80 bactérias. Resultados: A mediana das proporções de BRA foi significativamente maior nos casos (n = 22) que nos controles (n = 23) - IgA (60,6% vs. 22,5%), IgM (42,5% vs. 12,5%), IgG (50,6% vs. 17,5%) e polivalente (75,6% vs. 33,8%) - p < 0,001 para todos. A acurácia dos melhores pontos de corte para o diagnostico de PAVM em relação aos BRA monoclonais e polivalentes foi > 95,0% e > 93,3%, respectivamente. Conclusões: O número de BRA em amostras de AT foi maior nos casos que nos controles. Nossos achados indicam que a avaliação de BRA no AT é uma ferramenta promissora para aumentar a especificidade do diagnóstico de PAVM. A técnica pode ser custo-efetiva e, portanto, útil em locais com poucos recursos, com as vantagens de minimizar resultados falso-positivos e evitar o tratamento excessivo.


Subject(s)
Male , Female , Adult , Middle Aged , Aged , Antibodies, Bacterial/isolation & purification , Antibodies, Monoclonal/isolation & purification , Bacteria/isolation & purification , Pneumonia, Ventilator-Associated/diagnosis , Pneumonia, Ventilator-Associated/microbiology , Trachea/microbiology , Trachea/metabolism , Antibodies, Monoclonal/immunology , Bacterial Load , Bacteria/immunology , Intensive Care Units , Reference Values , Reproducibility of Results , Sensitivity and Specificity , Statistics, Nonparametric
5.
Article in English | WPRIM | ID: wpr-149376

ABSTRACT

BACKGROUND/AIMS: To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. METHODS: A total of 107 volunteers were enrolled. All subjects underwent a 13C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. RESULTS: H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups: one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 +/- 646.7 and 604.3 +/- 594.3 mumol/L (p > 0.05), and pH was 3.37 +/- 1.64 and 2.82 +/- 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. CONCLUSIONS: HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.


Subject(s)
Adult , Antibodies, Monoclonal/immunology , Bacterial Proteins/analysis , Biomarkers/analysis , Biopsy , False Negative Reactions , False Positive Reactions , Female , Gastritis, Atrophic/diagnosis , Helicobacter Infections/diagnosis , Helicobacter pylori/enzymology , Humans , Immunologic Tests , Male , Metaplasia , Middle Aged , Predictive Value of Tests , Pyloric Antrum/microbiology , Reproducibility of Results , Time Factors , Urease/analysis , Workflow
6.
ABCD arq. bras. cir. dig ; 28(1): 48-52, 2015. tab, graf
Article in English | LILACS | ID: lil-742757

ABSTRACT

BACKGROUND: Few studies evaluated the association between nutritional disorders, quality of life and weight loss in patients undergoing bariatric surgery. AIM: To identify nutritional changes in patients undergoing bariatric surgery and correlate them with weight loss, control of comorbidities and quality of life. METHOD: A prospective cohort, analytical and descriptive study involving 59 patients undergoing bariatric surgery was done. Data were collected preoperatively at three and six months postoperatively, evaluating nutritional aspects and outcomes using BAROS questionnaire. The data had a confidence interval of 95%. RESULTS: The majority of patients was composed of women, 47 (79.7%), with 55.9% of the series with BMI between 40 to 49.9 kg/m². In the sixth month after surgery scores of quality of life were significantly higher than preoperatively (p<0.05) and 27 (67.5 %) patients had comorbidities resolved, 48 (81.3 %) presented BAROS scores of very good or excellent. After three and six months of surgery 16 and 23 presented some nutritional disorder, respectively. There was no relationship between the loss of excess weight and quality of life among patients with or without nutritional disorders. CONCLUSION: Nutritional disorders are uncommon in the early postoperative period and, when present, have little or no influence on quality of life and loss of excess weight. .


RACIONAL: Poucos estudos avaliam a associação entre distúrbios nutricionais, qualidade de vida e perda de peso em pacientes submetidos à cirurgia bariátrica. OBJETIVO: Identificar alterações nutricionais em pacientes submetidos à cirurgia bariátrica e correlacioná-las com perda de peso, controle de comorbidades e qualidade de vida. MÉTODO: Estudo de coorte, prospectivo, analítico e descritivo envolvendo 59 pacientes submetidos à cirurgia bariátrica. Os dados foram coletados no pré-operatório e aos três e seis meses pós- operatórios, quantificando aspectos nutricionais e utilizando o Bariatric Analysis and Reporting Outcomes System (BAROS) como ferramenta de sucesso. Os dados usaram intervalo de confiança de 95%. RESULTADOS: O total de mulheres foi 47 (79,7%), sendo 55,9% com IMC entre 40-49,9 kg/m². No sexto mês depois da operação os escores de qualidade de vida foram significativamente maiores do que no pré-operatório (p<0,05) e 27 (67,5%) pacientes tinham todas comorbidades resolvidas, 48 (81,3%) apresentaram conceito BAROS muito bom ou excelente. Após três e seis meses 16 e 23 pacientes apresentaram algum distúrbio nutricional, respectivamente. Não houve relação entre a perda do excesso de peso e qualidade de vida entre pacientes com ou sem distúrbio nutricional. CONCLUSÃO: os distúrbios nutricionais são pouco frequentes no pós-operatório precoce e, quando presentes, têm pouca ou nenhuma influência na qualidade de vida e na perda do excesso de peso. .


Subject(s)
Animals , Humans , Mice , Antibodies, Monoclonal/immunology , Antigens, Tumor-Associated, Carbohydrate/immunology , Neoplasms/immunology , Polysaccharides/immunology , Antibody-Dependent Cell Cytotoxicity , Cell Line, Tumor , Epitopes , Fas Ligand Protein/analysis , Fas Ligand Protein/immunology , Glycosylation , Mice, Inbred BALB C , Mice, Inbred DBA , Mannose/analysis , Vaccination
7.
Article in English | WPRIM | ID: wpr-210701

ABSTRACT

Orientia tsutsugamushi, a causative pathogen of Scrub typhus, is a gram-negative intracellular bacterium. Outer membrane vesicles (OMVs) are produced from the membrane of bacteria and play many roles related to the survival of the pathogen. However, there have been no reports confirming whether O. tsutsugamushi indeed produce OMVs. O. tsutsugamushi boryong was cultured in ECV-304 cells for the purification of OMVs. Western blot analysis and immunoenrichment using anti-O. tsutsugamushi monoclonal antibody and electron microscopy were employed for identification and characterization of OMVs. We confirm the presence of OMVs derived from O. tsutsugamushi, and also found that those OMVs contain a major surface antigen of 56-kDa protein and variant immunogenic antigens.


Subject(s)
Antibodies, Monoclonal/immunology , Antigens, Bacterial/immunology , Antigens, Surface/immunology , Cell Line , Cell Membrane/immunology , Humans , Microscopy, Electron , Orientia tsutsugamushi/immunology , Scrub Typhus/diagnosis , Secretory Vesicles/immunology
8.
Article in English | WPRIM | ID: wpr-99846

ABSTRACT

Mucosal-associated invariant T (MAIT) cells and natural killer T (NKT) cells are known to play crucial roles in a variety of diseases, including autoimmunity, infectious diseases, and cancers. However, little is known about the roles of these invariant T cells in acute cholecystitis. The purposes of this study were to examine the levels of MAIT cells and NKT cells in patients with acute cholecystitis and to investigate potential relationships between clinical parameters and these cell levels. Thirty patients with pathologically proven acute cholecystitis and 47 age- and sex-matched healthy controls were enrolled. Disease grades were classified according to the revised Tokyo guidelines (TG13) for the severity assessment for acute cholecystitis. Levels of MAIT and NKT cells in peripheral blood were measured by flow cytometry. Circulating MAIT and NKT cell numbers were significantly lower in acute cholecystitis patients than in healthy controls, and these deficiencies in MAIT cells and NKT cell numbers were associated with aging in acute cholecystitis patients. Notably, a reduction in NKT cell numbers was found to be associated with severe TG13 grade, death, and high blood urea nitrogen levels. The study shows numerical deficiencies of circulating MAIT and NKT cells and age-related decline of these invariant T cells. In addition, NKT cell deficiency was associated with acute cholecystitis severity and outcome. These findings provide an information regarding the monitoring of these changes in circulating MAIT and NKT cell numbers during the course of acute cholecystitis and predicting prognosis.


Subject(s)
Aged , Antibodies, Monoclonal/immunology , Case-Control Studies , Cholecystitis, Acute/diagnosis , Female , Flow Cytometry , Humans , Leukocytes, Mononuclear/cytology , Male , Middle Aged , Natural Killer T-Cells/cytology , Patients , Prognosis , Severity of Illness Index , T-Lymphocyte Subsets/cytology
9.
Article in English | WPRIM | ID: wpr-115860

ABSTRACT

BACKGROUND: Bone marrow biopsies are routinely performed for staging patients with B-cell non-Hodgkin lymphoma (NHL). In addition to histomorphological studies, ancillary tools may be needed for accurate diagnosis. We investigated the clinical utility of multiparameter flow cytometric examination of bone marrow aspirates. METHODS: A total of 248 bone marrow specimens from 232 patients diagnosed with B-cell NHL were examined. Monoclonal antibodies directed against CD19, CD20, CD10 (or CD5), and kappa and lambda immunoglobulins were used. Multi-stage sequential gating was performed to select specific cells of interest, and the results were compared with bone marrow histology. RESULTS: The concordance rate between histomorphology and flow cytometry was 91.5% (n=227). Eight cases (3.2%) were detected by flow cytometry alone and were missed by histomorphology analysis, and 6 of these 8 cases showed minimal bone marrow involvement (0.09-2.2%). The diagnosis in these cases included large cell lymphoma (n=3), mantle cell lymphoma (n=3), and mucosa-associated lymphoid tissue (MALT) lymphoma (n=2). Thirteen cases were histopathologically positive and immunophenotypically negative, and the diagnoses in these cases included diffuse large cell lymphoma (n=7), T-cell/histiocyte-rich large B-cell lymphoma (n=2), anaplastic lymphoma kinase (ALK)-positive large B-cell lymphoma (n=1), follicular lymphoma (n=1), MALT lymphoma (n=1), and unclassifiable lymphoma (n=1). CONCLUSIONS: Multi-color flow cytometry can be a useful method for assessing bone marrow in staging NHL and also plays a complementary role, especially in detecting small numbers of lymphoma cells.


Subject(s)
Antibodies, Monoclonal/immunology , Antigens, CD19/immunology , Antigens, CD20/immunology , Bone Marrow/pathology , Female , Flow Cytometry , Humans , Immunophenotyping , Lymphoma, B-Cell/pathology , Male , Neoplasm Staging , Neprilysin/immunology
10.
Rev. cuba. farm ; 48(4)oct.-dic. 2014.
Article in Spanish | LILACS, CUMED | ID: lil-748783

ABSTRACT

La administración de drogas que bloquean el sistema del factor de crecimiento epidérmico y su receptor ha demostrado efectos beneficiosos en pacientes con tumores sólidos de origen epitelial. Cada día resulta más frecuente el uso de múltiples modalidades terapéuticas para combatir estos tumores, las cuales incluyen la asociación de agentes blanco y cirugía. Los agentes que actúan sobre dicho sistema pudieran causar trastornos de la cicatrización al bloquear vías del sistema que también intervienen en la cicatrización de las heridas. El objetivo de este artículo es revisar y comentar acerca del conocimiento de la relación entre el uso de las drogas anti-EGF/EGFR y los trastornos en la cicatrización de las heridas. La búsqueda bibliográfica se realizó en PubMed y Google (solo en español e inglés) y se tuvo en cuenta cualquier publicación encontrada hasta enero del 2014. Se incluyeron los anticuerpos monoclonales cetuximab, panitumumab y nimotuzumab; las pequeñas moléculas erlotinib y gefitinib y las vacunas terapéuticas contra el cáncer CIMAvax EGF y HER-1. Se hace especial énfasis en los biofarmacéuticos nimotuzumab, CIMAvax EGF y HER-1; producidos en el Centro de Inmunología Molecular, La Habana, Cuba, debido a su amplio uso en Cuba y otros países de América Latina. No se encontraron evidencias de relación entre el uso de estos productos y la aparición de trastornos en la cicatrización de las heridas. Dado que los tratamientos anti-EGF/EGFR también inhiben la proliferación celular que induce el drenaje de las heridas y la migración celular inducida por las radiaciones, se sugiere que el tratamiento anti-EGF/EGFR no debe suspenderse, ni antes ni después de la cirugía y sus posibles efectos deben ser vigilados. Obviamente, se necesitan ulteriores investigaciones por parte de los farmacólogos no clínicos y clínicos, oncólogos clínicos y cirujanos oncológicos para entender mejor los procesos fisiopatológicos de cicatrización en los cánceres de origen epitelial(AU)


The use of blocking drugs for epidermal growth factor and its receptor system has shown beneficial effects in patients with solid tumors of epithelial origin. It is increasingly common to use a multi-modal treatment approach towards solid tumors, often including the association of target agents and surgical resection. Some target agents can impair wound healing or cause increasing risk of perioperative complications if they block system pathways that may intervene in wound healing. The objective of this paper was to review and comment on the existing knowledge about the relationship between the use of anti-EGF/EGFR drugs and the disorders in wound healing. Citations from PubMed and Google (English and Spanish languages only) regardless of the date of publication were reviewed to identify potentially useful articles until January 2014. Monoclonal antibodies cetuximab, panitumumab, nimotuzumab; the small molecules erlotinib and gefitinib, and the therapeutic cancer vaccines called CIMAvax EGF and HER-1. Special emphasis was made on biopharmaceuticals nimotuzumab, CIMAvax EGF and HER-1, all of them produced at the Center of Molecular Immunology, Havana, Cuba, because of their extensive use in Cuba and many Latin-American countries. No evidence of association between the use of these products and the occurrence of complications in wound healing was found. Given that the anti-EGF/EGFR treatments also inhibit the tumor cell proliferation that wound drainage induces and the radiation-induced cell migration, it is suggested that that the administration of this kind of drugs should be kept before and after the surgery and consequently, its possible effects must be under surveillance. Obviously, non-clinical and clinical pharmacologists, clinical oncologists and surgeons need further researches for better understanding the pathophysiological wound healing processes in epithelial cancers(AU)


Subject(s)
Humans , Male , Female , Wound Healing , Cancer Vaccines/therapeutic use , Antibodies, Monoclonal/immunology , Neoplasms/surgery , Cuba
11.
Salud pública Méx ; 56(6): 619-624, nov.-dic. 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-733340

ABSTRACT

Objetivo. Conocer la seroprevalencia y detección de infección primaria por citomegalovirus (CMV) mediante prueba de avidez de inmunoglobulina G (IgG) durante el primer trimestre del embarazo en el Hospital General de Morelia, Michoacán. Material y métodos. Se estudiaron 177 pacientes mediante prueba de Elisa modificada, la cual utiliza inmunoanálisis quimioluminiscente de micropartículas (CMIA) para detección de anti-CMV (IgG e inmunoglobulina M [IgM]) e IgG avidez. Resultados. Del total de pruebas, 90.4% resultaron positivas para IgG; de éstas, 2.3% resultaron reactivas a IgM. En este segundo grupo, la prueba de IgG avidez reportó avidez baja en 1.1% y alta en el mismo porcentaje; 9.6% fueron seronegativas. Conclusiones. Se encontró similitud con lo publicado en México. Los profesionales de la salud deben conocer los algoritmos para el diagnóstico y manejo oportuno de la infección por CMV mediante la prueba de avidez de IgG.


Objective. To determine the seroprevalence and detection of primary infection by cytomegalovirus (CMV) with immunoglobulin G (IgG) avidity test during the first quarter of pregnancy in the General Hospital in Morelia, Michoacan. Materials and methods. A total of 177 patients were studied employing a modified Elisa test using a chemiluminescent microparticle immunoassay (CMIA) for the detection of CMV antibodies (IgG and immunoglobulin M [IgM]), and IgG avidity. Results. 90.4% were positive for IgG, and of these, 2.3% were also reactive for IgM, and in this group the IgG avidity test reported low avidity for 1.1% and higher avidity in the same percentage. 9.6% were seronegative. Conclusions. Similarity was found with published studies in Mexico. Health professionals should know the clinical algorithms for diagnosis and proper management of CMV infection using the IgG avidity test.


Subject(s)
Animals , Humans , Male , Mice , Antibodies, Monoclonal/immunology , Neoplasms/enzymology , Thymidine Phosphorylase/analysis , Enzyme-Linked Immunosorbent Assay , Floxuridine/metabolism , Fluorouracil/metabolism , Mice, Inbred BALB C , Thymidine Phosphorylase/immunology , Thymidine Phosphorylase/isolation & purification
12.
Article in English | WPRIM | ID: wpr-121886

ABSTRACT

This study was undertaken to characterize the properties of a 100 kDa somatic antigen from Metagonimus yokogawai. Monoclonal antibodies (mAbs) were produced against this 100 kDa antigen, and their immunoreactivity was assessed by western blot analysis with patients' sera. The mAbs against the 100 kDa antigen commonly reacted with various kinds of trematode antigens, including intestinal (Gymnophalloides seoi), lung (Paragonimus westermani), and liver flukes (Clonorchis sinensis and Fasciola hepatica). However, this mAb showed no cross-reactions with other helminth parasites, including nematodes and cestodes. To determine the topographic distribution of the 100 kDa antigen in worm sections, indirect immunoperoxidase staining was performed. A strong positive reaction was observed in the tegumental and subtegumental layers of adult M. yokogawai and C. sinensis. The results showed that the 100 kDa somatic protein of M. yokogawai is a common antigen which recognizes a target epitope present over the tegumental layer of different trematode species.


Subject(s)
Animals , Antibodies, Helminth/immunology , Antibodies, Monoclonal/immunology , Antigens, Helminth/immunology , Clonorchis sinensis/immunology , Cross Reactions/immunology , Fasciola hepatica/immunology , Female , Helminth Proteins/immunology , Heterophyidae/immunology , Immunologic Tests , Mice , Mice, Inbred BALB C , Paragonimus westermani/immunology , Trematode Infections/diagnosis
13.
J. bras. med ; 101(6)nov.-dez. 2013. ilus
Article in Portuguese | LILACS | ID: lil-712204

ABSTRACT

As dificuldades diagnósticas entre mesotelioma pleural e adenocarcinoma metastático na pleura exigem estudo amplo. Os autores ilustram um caso clínico cujo diagnóstico só foi estabelecido após realização de toracotomia, com retirada de material para análise imuno-histoquímica. A diferenciação diagnóstica é de fundamental importância, uma vez que envolvem conduta terapêutica e prognóstico distintos. O estudo adequado deve utilizar material obtido através de toracoscopia ou toracotomia e empregar coloração imuno-histoquímica, estudos com anticorpos monoclonais, microscopia eletrônica e pesquisa de marcadores tumorais.


The diagnosis difficulties distinguishing mesothelioma from pleural metastatic adenocarcinoma request wide study. The authors illustrate a clinical case whose diagnosis was only established after thoracotomy removing material for immune-histochemical analysis. The diagnosis differentiating is very important, because involves distinct treatment and prognosis. The appropriate study should use material obtained through thoracoscopy or thoracotomy and submitted to immune-histochemical coloration, studies with monoclonal antibodies, electronic microscopy and research of tumor makers.


Subject(s)
Humans , Pleural Neoplasms/diagnosis , Mesothelioma/diagnosis , Immunohistochemistry , Thoracotomy/instrumentation , Microscopy, Electron/instrumentation , Antibodies, Monoclonal/immunology
14.
Mem. Inst. Oswaldo Cruz ; 108(5): 616-622, ago. 2013. tab, graf
Article in English | LILACS | ID: lil-680767

ABSTRACT

The humoral immune response plays an important role in the clearance of Giardia lamblia. However, our knowledge about the specific antigens of G. lamblia that induce a protective immune response is limited. The purpose of this study was to identify and characterise the immunogenic proteins of G. lamblia in a mouse model. We generated monoclonal antibodies (moAbs) specific to G. lamblia (1B10, 2C9.D11, 3C10.E5, 3D10, 5G8.B5, 5F4, 4C7, 3C5 and 3C6) by fusing splenocytes derived from infected mice. Most of these moAbs recognised a band of ± 71 kDa (5G8 protein) and this protein was also recognised by serum from the infected mice. We found that the moAbs recognised conformational epitopes of the 5G8 protein and that this antigen is expressed on the cell surface and inside trophozoites. Additionally, antibodies specific to the 5G8 protein induced strong agglutination (> 70-90%) of trophozoites. We have thus identified a highly immunogenic antigen of G. lamblia that is recognised by the immune system of infected mice. In summary, this study describes the identification and partial characterisation of an immunogenic protein of G. lamblia. Additionally, we generated a panel of moAbs specific for this protein that will be useful for the biochemical and immunological characterisation of this immunologically interesting Giardia molecule.


Subject(s)
Animals , Mice , Antibodies, Monoclonal/immunology , Antibodies, Protozoan/immunology , Antigens, Protozoan/immunology , Giardia lamblia/immunology , Protozoan Proteins/immunology , Blotting, Western , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Giardiasis/immunology , Giardiasis/parasitology
15.
Biol. Res ; 46(3): 275-280, 2013. ilus, graf
Article in English | LILACS | ID: lil-692194

ABSTRACT

Galectin-8 belongs to a family of mammalian lectins that recognize glycoconjugates present on different cell surface components and modulate a variety of cellular processes. A role of Gal-8 in the immune system has been proposed based on its effects in immune cells, including T and B lymphocytes, as well as the presence of anti-Gal-8 autoantibodies in the prototypic autoimmune disease systemic lupus erythematosus (SLE). We have previously described that Gal-8 induces apoptosis in activated T cells interacting with certain β1 integrins and this effect is counteracted by the anti-Gal-8 autoantibodies. Given that Gal-8 can potentially interact with several glycoproteins, here we analyzed the β2 integrin Lymphocyte Function-Associated Antigen-1 (LFA-1), which is involved in leukocyte cell adhesion and immunological synapses. We show by GST-pull down assays that Gal-8 interacts with LFA-1 and this interaction is inhibited by anti-Gal-8 autoantibodies isolated from SLE patients. In cell adhesion assays, Gal-8 precluded the interaction of LFA-1 with its ligand Intracellular Adhesion Molecule-1 (ICAM-1). These results suggest that Gal-8 can exert immunosuppressive action not only by inducing apoptosis in activated T cells but also by negatively modulating the crucial function of LFA-1 in the immune system, while function-blocking autoantibodies counteract these effects.


Subject(s)
Humans , Galectins/metabolism , Intercellular Adhesion Molecule-1/metabolism , Lupus Erythematosus, Systemic/immunology , Lymphocyte Function-Associated Antigen-1/metabolism , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/metabolism , Autoantibodies/immunology , Autoantibodies/metabolism , Cell Adhesion
16.
Article in English | WPRIM | ID: wpr-142100

ABSTRACT

The follicle-associated epithelium (FAE) of Peyer's patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens.


Subject(s)
Animals , Antibodies, Monoclonal/immunology , Cattle , Fetus , Hybridomas , Ileum/ultrastructure , Intestinal Mucosa/immunology , Peyer's Patches/immunology
17.
Article in English | WPRIM | ID: wpr-142097

ABSTRACT

The follicle-associated epithelium (FAE) of Peyer's patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens.


Subject(s)
Animals , Antibodies, Monoclonal/immunology , Cattle , Fetus , Hybridomas , Ileum/ultrastructure , Intestinal Mucosa/immunology , Peyer's Patches/immunology
18.
Mem. Inst. Oswaldo Cruz ; 107(6): 713-719, set. 2012. ilus, tab
Article in English | LILACS | ID: lil-649484

ABSTRACT

Protein tyrosine phosphatases (PTPs) play an essential role in the regulation of cell differentiation in pathogenic trypanosomatids. In this study, we describe a PTP expressed by the non-pathogenic protozoan Trypanosoma rangeli (TrPTP2). The gene for this PTP is orthologous to the T. brucei TbPTP1 and Trypanosoma cruzi (TcPTP2) genes. Cloning and expression of the TrPTP2 and TcPTP2 proteins allowed anti-PTP2 monoclonal antibodies to be generated in BALB/c mice. When expressed by T. rangeli epimastigotes and trypomastigotes, native TrPTP2 is detected as a ~65 kDa protein associated with the parasite's flagellum. Given that the flagellum is an important structure for cell differentiation in trypanosomatids, the presence of a protein responsible for tyrosine dephosphorylation in the T. rangeli flagellum could represent an interesting mechanism of regulation in this structure.


Subject(s)
Animals , Mice , Antibodies, Monoclonal/immunology , Flagella/enzymology , Protein Tyrosine Phosphatases/metabolism , Trypanosoma rangeli/enzymology , Immunization , Mice, Inbred BALB C , Phylogeny , Protein Tyrosine Phosphatases/genetics , Trypanosoma rangeli/genetics , Trypanosoma rangeli/immunology
19.
Braz. j. med. biol. res ; 45(7): 583-590, July 2012. ilus
Article in English | LILACS | ID: lil-639469

ABSTRACT

Human cytomegalovirus glycoprotein B (gB) represents a target for diagnosis and treatment in view of the role it plays in virus entry and spread. Nevertheless, to our knowledge, rare detection of a gB antigen has been reported in transplant patients and limited information is available about diagnostic gB monoclonal antibodies (mAbs). Our aim was to develop gB mAbs with diagnostic potential. Hydrophilic gB peptides (ST: amino acids 27-40, SH: amino acids 81-94) of favorable immunogenicity were synthesized and used to immunize BALB/c mice. Two mAbs, named ZJU-FH6 and ZJU-FE6, were generated by the hybridoma technique and limited serial dilution and then characterized by indirect ELISA, Western blotting, immunoprecipitation, and immunohistochemical staining. The mAbs displayed high titers of specific binding affinities for the ST and SH synthetic peptides at an mAb dilution of 1:60,000 and 1:240,000, respectively. Western blotting and immunoprecipitation indicated that these mAbs recognized both denatured and native gB of the Towne and AD169 strains. The mAbs, when used as the primary antibody, showed positive staining in cells infected with both Towne and AD169 strains. The mAbs were then tested on patients submitted to allogeneic hematopoietic stem cell transplantation. The gB antigen positivity rates of the patients tested using ZJU-FH6 and ZJU-FE6 were 62.0 and 63.0%, respectively. The gB antigen showed a significant correlation with the level of pp65 antigen in peripheral blood leukocytes. In conclusion, two potential diagnostic gB mAbs were developed and were shown to be capable of recognizing gB in peripheral blood leukocytes in a reliable manner.


Subject(s)
Animals , Humans , Mice , Antibodies, Monoclonal , Antibodies, Viral/immunology , Cytomegalovirus Infections/diagnosis , Cytomegalovirus/immunology , Viral Envelope Proteins/immunology , Antibodies, Monoclonal/immunology , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Hematopoietic Stem Cell Transplantation , Immunohistochemistry , Immunoprecipitation , Mice, Inbred BALB C , Sensitivity and Specificity
20.
Mem. Inst. Oswaldo Cruz ; 107(2): 155-162, Mar. 2012. graf, tab
Article in English | LILACS | ID: lil-617059

ABSTRACT

The interleukin (IL)-2R alpha chain (CD25) is expressed on regulatory T cells (Treg), which constitute more than 85 percent of the CD25+ T cell population in a naïve mouse. CD25 is also expressed on effector T cells in mice suffering from an acute infection by the obligate intracellular protozoan parasite, Toxoplasma gondii. Lethal toxoplasmosis is accompanied by a significant loss of Treg in mice naturally susceptible to toxoplasmosis. The present study was done to explore the role of Treg cells using an anti-CD25 antibody-mediated depletion in mice naturally resistant to toxoplasmosis. Although a significant decrease in the percentage of Treg cells was observed following anti-CD25 monoclonal antibody injections, the depletion of CD25+ cells during acute toxoplasmosis did not significantly increase the mortality of Swiss OF1 mice and no significant difference was observed in the brain parasitic load between the mice in the depleted-infected and isotype-infected groups. We found no significant difference between the titres of total IgG in the sera of the mice from the two groups in the chronic phase. However, CD25+ cells depletion was followed by significantly higher levels of IL-12 in the serum of depleted mice than in that of mice injected with the isotype control antibody.


Subject(s)
Animals , Female , Mice , Antibodies, Monoclonal/immunology , /immunology , T-Lymphocytes, Regulatory/cytology , Toxoplasma/immunology , Toxoplasmosis/immunology , Acute Disease , Parasite Load , T-Lymphocytes, Regulatory/immunology , Toxoplasmosis/mortality , Toxoplasmosis/pathology
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