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Electron. j. biotechnol ; 44: 6-13, Mar. 2020. tab, graf, ilus
Article in English | LILACS | ID: biblio-1087627


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.

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
Article in English | LILACS | ID: biblio-954857


Among other applications, immunotherapy is used for the post-exposure treatment and/or prophylaxis of important infectious diseases, such as botulism, diphtheria, tetanus and rabies. The effectiveness of serum therapy is widely proven, but improvements on the immunoglobulin purification process and on the quality control are necessary to reduce the amount of protein aggregates. These may trigger adverse reactions in patients by activating the complement system and inducing the generation of anaphylatoxins. Herein, we used immunochemical methods to predict the quality of horse F(ab′)2 anti-botulinum AB, anti-diphtheric, antitetanic and anti-rabies immunoglobulins, in terms of amount of proteins and protein aggregates. Methods Samples were submitted to protein quantification, SDS-PAGE, Western blot analysis and molecular exclusion chromatography. The anticomplementary activity was determined in vitro by detecting the production of C5a/C5a desArg, the most potent anaphylatoxin. Data were analyzed by one-way ANOVA followed by Tukey's post-test, and differences were considered statistically significant when p < 0.05. Results Horse F(ab′)2 antitoxins and anti-rabies immunoglobulin preparations presented different amounts of protein. SDS-PAGE and Western blot analyses revealed the presence of protein aggregates, non-immunoglobulin contaminants and, unexpectedly, IgG whole molecules in the samples, indicating the non-complete digestion of immunoglobulins. The chromatographic profiles of antitoxins and anti-rabies immunoglobulins allowed to estimate the percentage of contaminants and aggregates in the samples. Although protein aggregates were present, the samples were not able to induce the generation of C5a/C5a desArg in vitro, indicating that they probably contain acceptable levels of aggregates. Conclusions Anti-botulinum AB (bivalent), anti-diphtheric, antitetanic and anti-rabies horse F(ab′)2 immunoglobulins probably contain acceptable levels of aggregates, although other improvements on the preparations must be carried out. Protein profile analysis and in vitro anticomplementary activity of F(ab′)2 immunoglobulin preparations should be included as quality control steps, to ensure acceptable levels of aggregates, contaminants and whole IgG molecules on final products, reducing the chances of adverse reactions in patients.(AU)

Animals , Male , Female , Immunoglobulins/immunology , Immunoglobulin Fab Fragments/isolation & purification , Botulinum Antitoxin/isolation & purification , Rabies Vaccines/analysis , Immunoglobulins , Horses/immunology
Rev. bras. parasitol. vet ; 26(2): 205-210, Apr.-June 2017. graf
Article in English | LILACS | ID: biblio-899280


Abstract In this study, a method for expressing Cryptosporidium hominis GP60 glycoprotein in Escherichia coli for production of polyclonal anti-GP60 IgY in chickens was developed aiming future studies concerning the diagnosis, prevention and treatment of cryptosporidiosis. The full-length nucleotide sequence of the C. hominis gp60 gene was codon-optimized for expression in E. coli and was synthesized in pET28-a vector. Subcloning was performed on several different strains of BL21 E. coli. Temperature, time and inducer IPTG concentration assays were also performed and analyzed using SDS-PAGE. The optimal conditions were observed at a temperature of 37 °C, with overnight incubation and 1 mM of IPTG. Purification was performed by means of affinity chromatography using the AKTA Pure chromatography system and the Hi-Trap™ HP column (GE Healthcare). The recombinant protein GP60 (rGP60) thus generated was used to immunize laying hens owing the production of polyclonal IgY. Western blot and indirect immunofluorescence showed that the polyclonal antibody was capable of binding to rGP60 and to Cryptosporidium parvum sporozoites, respectively. The rGP60 and the IgY anti-rGP60 generated in this study may be used as templates for research and for the development of diagnostic methods for cryptosporidiosis.

Resumo Neste trabalho, foi desenvolvido um método de expressão da glicoproteína GP60 de Cryptosporidium hominis em Escherichia coli visando produzir anticorpos IgY anti-GP60 em galinhas para utilização em estudos futuros com os objetivos de diagnóstico, prevenção e tratamento da criptosporidiose. A sequência completa de nucleotídeos do gene gp60 de C. hominis foi códon-otimizada para expressão em E. coli e sintetizada no vetor pET28-a. A subclonagem foi realizada em várias estirpes diferentes de E. coli BL21. Os ensaios de concentração do indutor IPTG, temperatura e tempo foram realizados e analisados por SDS-PAGE. As condições ótimas de expressão foram observadas em temperatura de 37 °C, incubação durante a noite e 1 mM de IPTG. A purificação da proteína foi realizada por cromatografia de afinidade utilizando o sistema de cromatografia AKTA Pure e a coluna Hi-Trap™ HP (GE Healthcare). A proteína recombinante GP60 (rGP60) foi utilizada para imunizar galinhas poedeiras para produzir IgY policlonal anti-rGP60. Verificou-se por Western blot e por imunofluorescência indireta que o anticorpo policlonal apresentou reatividade com a rGP60 e com esporozoítos de Cryptosporidium parvum, respectivamente. A rGP60 e a IgY anti-rGP60 geradas neste estudo podem ser utilizadas como modelos para o desenvolvimento de ensaios para pesquisa e diagnóstico da criptosporidiose.

Animals , Female , Immunoglobulins/immunology , Chickens/immunology , Cryptosporidiosis/diagnosis , Cryptosporidium/chemistry , Recombinant Proteins/metabolism , Recombinant Proteins/chemistry , Cryptosporidiosis/immunology , Escherichia coli/metabolism
Mem. Inst. Oswaldo Cruz ; 110(8): 989-995, Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769835


Leptospirosis is a zoonotic disease caused by pathogenic spirochetes of theLeptospira genus. Vaccination with bacterins has severe limitations. Here, we evaluated the N-terminal region of the leptospiral immunoglobulin-like B protein (LigBrep) as a vaccine candidate against leptospirosis using immunisation strategies based on DNA prime-protein boost, DNA vaccine, and subunit vaccine. Upon challenge with a virulent strain ofLeptospira interrogans, the prime-boost and DNA vaccine approaches induced significant protection in hamsters, as well as a specific IgG antibody response and sterilising immunity. Although vaccination with recombinant fragment of LigBrep also produced a strong antibody response, it was not immunoprotective. These results highlight the potential of LigBrep as a candidate antigen for an effective vaccine against leptospirosis and emphasise the use of the DNA prime-protein boost as an important strategy for vaccine development.

Animals , Cricetinae , Female , Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Bacterial Vaccines/immunology , Leptospira/immunology , Leptospirosis/prevention & control , Vaccination/methods , Adjuvants, Immunologic , Biopsy , Chlorocebus aethiops , Conserved Sequence , Enzyme-Linked Immunosorbent Assay , Immunity, Humoral/immunology , Immunoglobulin A/genetics , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulins/genetics , Immunoglobulins/immunology , Kidney/pathology , Leptospirosis/immunology , Lung/pathology , Mesocricetus , Survival Analysis , Vero Cells , Vaccines, DNA/immunology , Vaccines, Synthetic/immunology , Vaccines, Synthetic/microbiology
Femina ; 42(4): 185-192, jul-ago. 2014.
Article in Portuguese | LILACS | ID: lil-737135


Se ha considerado que el útero gestante es un lugar inmunológicamente privilegiado, donde el feto es protegido del rechazo por el sistema inmune materno, mediante un amplio repertorio de estrategias de evasión que contribuye a la sobrevivencia del feto. La gestación en sí misma constituye un acontecimiento de equilibrio inmunológico y la tolerancia inmunológica permite la progresión del embarazo, donde participan una secuencia sincronizada de eventos que se inicia desde la concepción y fertilización para dar lugar a la implantación y progresa hasta alcanzar un embarazo a término. El sistema inmune es la principal barrera que poseemos para protegernos de las infecciones. Durante la vida intrauterina, el feto está protegido por la madre de las agresiones externas, por lo que no necesita que su sistema inmunológico sea operativo, sin embargo, al nacer, recibe una avalancha de elementos extraños, por lo que necesitará disponer de cierta protección, así como una preparación para ejecutar las defensas necesarias para su protección inmunológica. La inmunidad sérica durante la vida fetal queda limitada a la transferencia a través de la placenta de IgG materna, a pesar de que el feto tiene la facultad de sintetizar inmunoglobulinas desde las primeras etapas de la gestación. Al nacimiento, el niño tiene su sistema inmunológico completo, aunque inmaduro, pero es capaz de responder a los estímulos antigénicos. Tiene múltiples anormalidades en el desarrollo de su sistema inmune, que involucran a los anticuerpos/inmunoglobulinas, complemento y granulocitos pudiendo contribuir a la alta incidencia de sus infecciones. El recién nacido carece de memoria inmunológica debido a que, en condiciones normales, el feto está exento de estímulos producidos por antígenos extraños. Dicha memoria se va adquiriendo a medida que entra en contacto con los diferentes antígenos. Se obtendrá cierta protección a las infecciones entéricas gracias a las IgA que aporta la lactancia materna. La exposición prenatal y postnatal a productos microbianos ambientales que pueden activar la inmunidad innata, puede acelerar el proceso de maduración del sistema inmune.(AU)

It has been considered the pregnant women`s womb as an immunological exceptional place, where fetus is protected against been rejected because of maternal immune system by means of a wide groups of evasive strategies that help in its survival. Pregnancy itself is an immunological equilibrium state and the immunological tolerance allow the progression of this event, where participate a synchronized sequence of biological events started from conception and fertilization to allow the implantation, and progress until to reach the pregnancy end. The immune system is our main barrier against infections. During intrauterine life fetus is protected by the mother against external aggressions, therefore he don`t need an operative immune system, nevertheless, at birth the new organisms receive an avalanche of strange elements needing some kind of protection as well as a preparation to carry out the necessary defense for his immunological protection. Serum immunity during fetal life is limited to the transference of maternal IgG through placenta, despite fetus capability to synthesize immunoglobulins from first stages of gestation. At birth the babe has a complete immunological system although immature but capable to respond to antigenic stimulus. He has multiples abnormalities in the immune system development that take account antibodies/immunoglobulin, complement and granulocytes contributing to his high incidence of infections. Newborn lack immunological memory because in normal conditions fetus is not stimulated by odd antigens. This memory is acquired through the contact with different antigens. It will be obtained some protection against enteric infections because IgA from maternal lactation. The prenatal and postnatal exposition to environmental microbial products that activate the innate immunity can accelerate the immune system maturing process.(AU)

Female , Pregnancy , Infant, Newborn , Immunoglobulins/immunology , Infant, Newborn/immunology , Infant, Premature/immunology , Fetus/immunology , Immunity, Maternally-Acquired/immunology , Antibodies/immunology , Pregnancy/immunology , B-Lymphocytes/immunology , Adaptive Immunity/immunology , Microbiological Phenomena/immunology , Milk, Human/immunology
Yonsei Medical Journal ; : 999-1004, 2014.
Article in English | WPRIM | ID: wpr-113975


PURPOSE: House dust mites (HDMs) are an important source of indoor allergens associated with asthma, rhinitis and atopic dermatitis. Chicken immunoglobulin (Ig) Y is known to be a good alternative to mice and rabbit antibody production. In this study, we produced IgYs specific to HDMs and investigated their IgE immunoreactivities. MATERIALS AND METHODS: Total IgYs were isolated from the yolks of White Leghorn hens immunized with either Dermatophagoides pteronyssinus or D. farinae protein extract. Control antibodies were separated from the yolks of immunized hens with phosphate buffered saline. IgYs specific to HDMs were analyzed using enzyme-linked immunosorbent assay and Western blotting analysis. RESULTS: The concentration of egg IgY specific to D. farinae in an immunized hen increased and the highest achieved was 661.3 ug/mg (per an egg) on day 47, compared with 760 ug/mg IgY specific to D. pteronyssinus on day 16. The D. pteronyssinus or D. farinae-specific IgY was detected by binding of each mite proteins, and their immunoreactivities were elevated dependent of the specific IgY concentration. CONCLUSION: IgY specific to HDMs may be a promising antibody for immunological diagnosis as well as identification of possible resistance relating to HDM allergy.

Allergens/immunology , Animals , Antibodies/immunology , Chickens , Egg Yolk/immunology , Female , Immunoglobulins/immunology , Pyroglyphidae/immunology
Invest. clín ; 54(3): 257-269, sep. 2013. ilus
Article in English | LILACS | ID: lil-740324


Neuregulins (NRG) are proteins that belong to the family of epidermal growth factors. It is well established that these factors are essential for the development and maintenance of the nervous system. Due to the difficulty of purifying enough quantities of these factors and the lack of specificity from commercially available antibodies, the aim of this work was to produce antibodies against a synthetic peptide capable to detect and identify neuregulin GGFb isoforms. To accomplish this goal, polyclonal antibodies were raised in hens against a synthetic peptide designed from the GGFb1 extracellular sequence. The sequence analysis was made using different epitope-predicting programs. Our results showed that the peptide sequence selected was immunogenic because it was capable of inducing a specific type B immune response in the experimental animal model. These antibodies were also capable of recognizing a recombinant GGF protein and GGF isoforms present in different samples. Our results suggest that the development of immunoglobulin Y (IgY) using synthetic peptides represents, a valuable tool for neuroscience research.

Las Neuregulinas (NRG) son proteínas que pertenecen a la familia de los factores de crecimiento epidermal. Se ha demostrado que estos factores son esenciales para el desarrollo y mantenimiento de la funcionalidad del sistema nervioso. Debido a la dificultad para purificar estas proteínas y la falta de especificidad de los anticuerpos disponibles comercialmente, el objetivo de este trabajo fue producir anticuerpos contra un péptido sintético capaz de detectar e identificar una isoforma de la Neuregulina (GGFb). Para lograr este objetivo, se desarrollaron anticuerpos en gallinas (IgY) contra un péptido sintético diseñado a partir de la secuencia aminoacídica de la región extracelular de GGFb, utilizando programas de predicción de epítopes. Los resultados demuestran que el péptido seleccionado fue immunogénico debido a que estimuló una respuesta inmune específica tipo B en el modelo utilizado. Estos anticuerpos fueron también capaces de reconocer una proteína recombinante e isoformas de GGF presentes en diferentes muestras biológicas. Nuestros resultados demuestran el potencial valor de las inmunoglobulinas Y (IgY) contra péptidos sintéticos como una herramienta de aplicación para la investigación en neurociencia.

Animals , Female , Rats , Antibodies, Heterophile/immunology , Chickens/immunology , Immunoglobulins/immunology , Neuregulin-1/immunology , Peptide Fragments/immunology , Antibody Specificity , Antibodies, Heterophile/biosynthesis , Antibodies, Heterophile/isolation & purification , Cells, Cultured , Culture Media, Conditioned , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Epitopes/immunology , Immunoblotting , Immunoglobulins/biosynthesis , Immunoglobulins/isolation & purification , Neuregulin-1/analysis , Peptide Fragments/chemical synthesis , Protein Isoforms/analysis , Protein Isoforms/immunology , Rats, Sprague-Dawley , Recombinant Proteins/immunology , Schwann Cells/immunology , Schwann Cells/metabolism , Sciatic Nerve/cytology
Biomédica (Bogotá) ; 32(1): 145-157, ene.-mar. 2012. ilus, graf
Article in Spanish | LILACS | ID: lil-639819


Hay diversos vínculos entre las parasitosis, especialmente las helmintiasis, y las enfermedades alérgicas, ambas condiciones de importancia epidemiológica en las regiones tropicales. Mientras que se ha especulado con frecuencia los efectos de las enfermedades parasitarias sobre la evolución del sistema inmunitario, no se conocen las fuerzas selectivas que han moldeado la respuesta alérgica y pensamos que incluyen mecanismos evolutivos distintos a los tradicionalmente divulgados. Los helmintos, fuente infecciosa y antigénica inductora de una respuesta parecida a la alérgica, se establecieron como parásitos en huéspedes que ya tenían grupos celulares de inmunidad de tipo 2. Hoy sabemos que un componente esencial en la relación de parasitismo entre los helmintos y sus huéspedes es la inmunosupresión que los primeros inducen, al crear una especie de equilibrio que permite la supervivencia de ambos. El desarrollo de este equilibrio debió incluir adaptaciones de ambos organismos y la supervivencia del parásito podría ser el resultado de la adquisición de mecanismos supresores de la respuesta defensiva, la selección de los huéspedes con menor intensidad de la respuesta de tipo 2, o ambas. Esto, a su vez, sugiere que aunque las infecciones helmínticas hayan influido en la conformación de la inmunidad de tipo 2, no han sido una fuerza selectiva importante en el caso particular de la respuesta alérgica que, a su vez, está más ligada a una exagerada respuesta Th2/IgE.

A variety of links occur between parasites, particularly helminths, and allergic diseases--both common conditions of epidemiological importance in tropical regions. Although speculations are often made about the effects of parasitic diseases on the evolution of the immune system, the selective forces that have shaped the allergic response are unknown and probably include evolutionary mechanisms different to those traditionally reported. Helminths, infectious and antigenic sources that induce allergic-like responses, established themselves as parasites in organisms that already had cell groups related to the type 2 immunity. An essential component in the relationship between helminths and their hosts is that the former induce immunosuppression, creating a kind of balance that allows the survival of both. The development of this equilibrium undoubtedly includes adaptations in both organisms, and the survival of the parasite is the result of (a) acquiring immune suppressor mechanisms and (b) finding hosts with lower intensity of the type 2 response. This in turn suggests that although helminth infections have influenced the formation of type 2 immunity, they have not been an important selective force in the particular case of allergic response. The latter is more related to an exaggerated Th2/IgE response.

Animals , Humans , Hypersensitivity/immunology , Parasitic Diseases/immunology , /immunology , Adaptation, Physiological/immunology , Allergens/immunology , Antibodies, Helminth/immunology , Cytokines/immunology , Disease Susceptibility , Evolution, Molecular , Helminthiasis/immunology , Host-Parasite Interactions/immunology , Immunity, Cellular , Immunity, Innate , Immunoglobulin E/immunology , Immunoglobulin G/immunology , Immunoglobulins/immunology , Invertebrates/immunology , Phylogeny , Receptors, Cytokine/immunology , Species Specificity , Vertebrates/immunology
Pesqui. vet. bras ; 31(3): 247-254, Mar. 2011. ilus
Article in English | LILACS | ID: lil-582688


Foi padronizado um ensaio imunoenzimático do tipo indireto para detecção de imunoglobulina A (ELISA IgA) anti- Campylobacter fetus subp. venerealis em muco cérvico- vaginal bovino utilizando um extrato protéico de Campylobacter fetus subsp. venerealis produzido pelo método de extração ácida pelo tampão de glicina (0,2M; pH2,2). A média dos valores de densidade ótica (DO450) foi de 0,143±0,09. As bandas protéicas dos antígenos de Campylobacter fetus subsp. venerealis e de Campylobacter fetus subsp. fetus melhor reconhecidas pela IgA do muco cérvico- vaginal migraram em 42,6 kDa mas a proteina evidenciada em 93 kDa foi reconhecida exclusivamente pelo Campylobacter fetus subsp. venerealis. Os anticorpos presentes na amostra de muco vaginal testada no “immunoblotting” que apresentou resultado positivo no ELISA IgA, reconheceu antígenos de C. jejuni subsp. jejuni e C. fetus subsp. fetus.

An indirect enzyme-linked immunosorbent assay was developed to detect antigenspecific secretory IgA antibodies to Campylobacter fetus subsp. venerealis in bovine vaginal mucus with a protein extract of the Campylobacter fetus subsp. venerealis by the acid glycine extraction method. Mean optical density measurement (λ=450 nm) was 0.143±0.9. The most immunoreactive protein bands of the Campylobacter fetus subsp. venerealis or Campylobacter fetus subsp. fetus recognized by IgA in immunoblotting, using bovine vaginal mucus samples, migrate at 42.6 kDa. The protein that migrates at 93 kDa was recognized exclusively for C. fetus subsp. venerealis. A positive vaginal mucus sample of a cow from negative herd recognized antigens of C. jejuni subsp. jejuni e C. fetus subsp. fetus.

Animals , Cattle/classification , Campylobacter fetus/immunology , Immunoglobulins/immunology , Immunoenzyme Techniques/methods
Mem. Inst. Oswaldo Cruz ; 106(1): 32-37, Feb. 2011. ilus, graf, tab
Article in English | LILACS | ID: lil-578813


In America, there are two species of Trypanosoma that can infect humans: Trypanosoma cruzi, which is responsible for Chagas disease and Trypanosoma rangeli, which is not pathogenic. We have developed a model of vaccination in mice with T. rangeli epimastigotes that protects against T. cruzi infection. The goal of this work was to study the pattern of specific immunoglobulins in the peritoneum (the site of infection) and in the sera of mice immunized with T. rangeli before and after challenge with T. cruzi. Additionally, we studied the effects triggered by antigen-antibodies binding and the levels of key cytokines involved in the humoral response, such as IL-4, IL-5 and IL-6. The immunization triggered the production of antibodies reactive with T. cruzi in peritoneal fluid (PF) and in serum, mainly IgG1 and, to a lesser magnitude, IgG2. Only immunized mice developed specific IgG3 antibodies in their peritoneal cavities. Antibodies were able to bind to the surface of the parasites and agglutinate them. Among the cytokines studied, IL-6 was elevated in PF during early infection, with higher levels in non-immunized-infected mice. The results indicate that T. rangeli vaccination against T. cruzi infection triggers a high production of specific IgG isotypes in PF and sera before infection and modulates the levels of IL-6 in PF in the early periods of infection.

Animals , Mice , Antibodies, Protozoan/immunology , Antigens, Protozoan/immunology , Chagas Disease/immunology , Immunoglobulins/immunology , /immunology , Protozoan Vaccines/immunology , Trypanosoma rangeli/immunology , Antibodies, Protozoan/blood , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique, Indirect , Hemagglutination Tests , Interleukins/immunology , Mice, Inbred BALB C
Braz. j. med. biol. res ; 43(12): 1215-1224, Dec. 2010. ilus, tab
Article in English | LILACS | ID: lil-568996


Rubinstein-Taybi syndrome (RTS) is a rare developmental disorder characterized by craniofacial dysmorphisms, broad thumbs and toes, mental and growth deficiency, and recurrent respiratory infections. RTS has been associated with CREBBP gene mutations, but EP300 gene mutations have recently been reported in 6 individuals. In the present study, the humoral immune response in 16 RTS patients with recurrent respiratory infections of possible bacterial etiology was evaluated. No significant differences between patients and 16 healthy controls were detected to explain the high susceptibility to respiratory infections: normal or elevated serum immunoglobulin levels, normal salivary IgA levels, and a good antibody response to both polysaccharide and protein antigens were observed. However, most patients presented high serum IgM levels, a high number of total B cell and B subsets, and also high percentiles of apoptosis, suggesting that they could present B dysregulation. The CREBBP/p300 family gene is extremely important for B-cell regulation, and RTS may represent an interesting human model for studying the molecular mechanisms involved in B-cell development.

Adolescent , Child , Child, Preschool , Female , Humans , Male , Young Adult , Antibodies, Monoclonal/analysis , B-Lymphocytes/immunology , Immunity, Humoral/immunology , Immunoglobulins/analysis , Respiratory Tract Infections/immunology , Rubinstein-Taybi Syndrome/immunology , Antibodies, Monoclonal/immunology , Case-Control Studies , CREB-Binding Protein/genetics , Immunity, Humoral/genetics , Immunoglobulins/immunology , Recurrence
Sudan Medical Journal. 2008; 44 (1-3): 35-41
in English | IMEMR | ID: emr-108415


Although antibodies are essential mediators of immunity, high levels of IgG antibodies against a wide range of blood-stage antigens of P. falciparum are poor predictors of clinical protection. It is the qualitative and the functional specificity of the antibodies to malaria antigens that predict the development of a clinically potent protective immunity. The objective of this work is to study the pattern of IgG sub-class in healthy and malaria-infected adults resident in a malaria-endemic area in Sudan. Total plasma IgG and IgG subclasses [IgG1, 2, 3 and 4] against the C-terminal region of the MSA-1[19] antigen of Plasmodium falciparum were measured by a quantitative enzyme-linked immunosorbent assay [ELISA] in 30 adult patients presenting to the emergency department with cerebral malaria [CM]. The levels of IgG antibody profile in CM patients were compared with those in patients with uncomplicated acute malaria [n=20] and in clinically healthy asymptomatic volunteers [n=20]. Total plasma IgG level was significantly higher in CM patients. The level of the sub-class IgG1 antibody against MSA-119 was significantly lower in patients infected with P. falciparum; the lowest values being observed in CM patients and the highest values in the clinically healthy volunteers. Our data suggest that acquisition of IgG1 antibody to MS A-1[19] is associated with a clinically protective immunity and that low production or defective IgG1 response may be associated with severe form of malaria in adults

Humans , Male , Female , Adult , Malaria, Cerebral/immunology , Immunoglobulins/immunology , Immunity, Humoral
J Health Popul Nutr ; 2007 Dec; 25(4): 465-8
Article in English | IMSEAR | ID: sea-719


The role of specific immunoglobulins at mucosal sites in imparting protection against disease, such as rotavirus-associated diarrhoea, is well-established. Oral immunoglobulin therapy with egg yolk-derived anti-rotavirus immunoglobulins has previously been shown to achieve moderate therapeutic effect in diarrhoea due to rotavirus in a clinical trial. Here, data on the therapeutic potential of the same immunoglobulin preparation in an infant mouse model of rotavirus-induced diarrhoea is presented. The use of an animal model has allowed therapy to be evaluated with higher doses of immunoglobulins and has suggested that an improved therapeutic effect can be achieved by increasing the dose in the clinical setting.

Animals , Animals, Suckling , Antibodies, Viral/biosynthesis , Antigens, Viral/immunology , Diarrhea/immunology , Disease Models, Animal , Egg Yolk/immunology , Humans , Immunization, Passive , Immunoglobulins/immunology , Mice , Mice, Inbred BALB C , Random Allocation , Rotavirus/immunology , Rotavirus Infections/immunology
Rev. Inst. Med. Trop. Säo Paulo ; 49(2): 97-101, Mar.-Apr. 2007. tab, ilus
Article in English | LILACS | ID: lil-449795


Since there are no studies evaluating the participation of the complement system (CS) in Jorge Lobo's disease and its activity on the fungus Lacazia loboi, we carried out the present investigation. Fungal cells with a viability index of 48 percent were obtained from the footpads of BALB/c mice and incubated with a pool of inactivated serum from patients with the mycosis or with sterile saline for 30 min at 37 °C. Next, the tubes were incubated for 2 h with a pool of noninactivated AB+ serum, inactivated serum, serum diluted in EGTA-MgCl2, and serum diluted in EDTA. The viability of L. loboi was evaluated and the fungal suspension was cytocentrifuged. The slides were submitted to immunofluorescence staining using human anti-C3 antibody. The results revealed that 98 percent of the fungi activated the CS by the alternative pathway and no significant difference in L. loboi viability was observed after CS activation. In parallel, frozen histological sections from 11 patients were analyzed regarding the presence of C3 and IgG by immunofluorescence staining. C3 and IgG deposits were observed in the fungal wall of 100 percent and 91 percent of the lesions evaluated, respectively. The results suggest that the CS and immunoglobulins may contribute to the defense mechanisms of the host against L. loboi.

Considerando que não existe nenhum estudo avaliando a participação do sistema complemento (SC) na doença de Jorge Lobo e sua atividade sobre o fungo Lacazia loboi, realizamos o presente trabalho. Os fungos foram obtidos dos coxins plantares de camundongos BALB/c com índice de viabilidade de 48 por cento e, em seguida, foram incubados com pool de soro inativado de pacientes ou com solução salina estéril (SSE) por 30 min, a 37 °C. Os tubos foram incubados, por 2 h, com pool de soro AB+ sem inativar, inativado, diluído em EGTA-MgCl2 e EDTA. A viabilidade do L. loboi foi avaliada e a suspensão fúngica foi citocentrifugada. As lâminas foram submetidas à técnica de imunofluorescência empregando o anticorpo anti-C3 humano. Os resultados revelaram que 98 por cento dos fungos ativaram o SC pela via alternativa e que não houve diferença significante na viabilidade do L. loboi após ativação do SC. Em paralelo, cortes histológicos congelados de 11 pacientes foram avaliados quanto à presença de C3 e IgG, pela técnica de imunofluorescência. Foram encontrados depósitos de C3 e de IgG na parede dos fungos em 100 por cento e 91 por cento das lesões avaliadas, respectivamente. Os resultados sugerem que o SC e as imunoglobulinas poderiam contribuir nos mecanismos de defesa do hospedeiro contra o L. loboi.

Humans , Animals , Mice , Complement Activation/physiology , Complement System Proteins/physiology , Immunoglobulins/immunology , Paracoccidioides/physiology , Complement Activation/immunology , /immunology , /physiology , Complement System Proteins/immunology , Fluorescent Antibody Technique , Mice, Inbred BALB C , Paracoccidioides/immunology
Arq. gastroenterol ; 44(1): 44-48, jan.-mar. 2007. graf
Article in English | LILACS | ID: lil-455960


BACKGROUND: Surgical treatment of hemorrhagic complication in schistosomal portal hypertension in our hospital is an esophagogastric devascularization procedure with splenectomy. Infectious risks and immunological alterations imputed to splenectomy may have significant importance. To minimize the consequences of spleen absence, the use of subtotal splenectomy and spleen auto-transplantation were stimulated. AIM: To verify the immunologic alterations imposed by this procedure in our patients. METHOD: Twenty-eight patients with schistosomal portal hypertension and previous history of upper digestive bleeding due to esophagogastric varices rupture underwent elective esophagogastric devascularization and splenectomy. They were prospectively studied before esophagogastric devascularization procedure with splenectomy, 15 and 30 days, 3 and 6 months after the procedure. T and B-lymphocytes, CD4 and CD8 subpopulations were determinated by monoclonal antibodies. Immunoglobulins A, M, G and C3, C4 components of the complement were determinated by radial immunodiffusion. RESULTS: We observed important reduction of all immune cells, increase of IgG and normal levels of IgM, IgA, C3 and C4 at preoperative. CD4/CD8 relation was normal. Six months after esophagogastric devascularization procedure with splenectomy, significant increase in T-lymphocytes, CD4, CD8 and B-lymphocytes were observed. CD4/CD8 relation remained normal. We noted significant increase in C3. IgA, IgM, IgG and C4 had increased, but without significant difference. CONCLUSION: Esophagogastric devascularization procedure with splenectomy determines an increase in T and B-lymphocytes, CD4 and CD8 subpopulations without compromising immunoglobulins and components of complement levels.

RACIONAL: A cirurgia de desconexão ázigo-portal com esplenectomia é utilizada no tratamento da complicação hemorrágica varicosa dos esquistossomóticos hepatoesplênicos com hipertensão do sistema portal, no Serviço de Fígado e Hipertensão Portal da Santa Casa de São Paulo. Envolvendo a esplenectomia, os riscos infecciosos e alterações imunológicas imputados a ela têm importância significativa. A esplenectomia subtotal e o auto-implante esplênico foram alternativas descritas para minimizar as conseqüências da esplenectomia nesses doentes. OBJETIVO: Avaliar o estado imunológico dos esquistossomóticos hepatoesplênicos e qual a alteração imunológica imposta pelo procedimento nesses doentes. MÉTODO: Vinte e oito esquistossomóticos com hipertensão portal e episódio hemorrágico varicoso foram estudados prospectivamente antes, 15 e 30 dias e 3 e 6 meses após a desconexão ázigo-portal com esplenectomia. Realizou-se contagem de linfócitos T, B, células CD4+ e CD8+ através de anticorpos monoclonais e dosagem das imunoglobulinas A, M, G e frações C3 e C4 do sistema complemento por imunodifusão radial. RESULTADOS: Obteve-se diminuição importante de todas as células, aumento de IgG e níveis normais de IgM, IgA, C3 e C4 no pré-operatório. A relação CD4+/CD8+ foi normal. Seis meses após a cirurgia, houve aumento significativo do número de linfócitos T, CD4+, CD8+ e linfócitos B. A relação CD4+/CD8+ manteve-se normal, sem variação. Houve aumento significativo nos níveis de C3. IgA, IgM, IgG e C4 também aumentaram, mas sem diferença significativa. CONCLUSÃO: Os linfócitos T, suas subpopulações CD4+ e CD8+, e os linfócitos B estão diminuídos no pré-operatório. Decorridos 6 meses da desconexão ázigo-portal com esplenectomia houve aumento do número de linfócitos T, das subpopulações CD4+ e CD8+, e dos linfócitos B. Após a desconexão ázigo-portal com esplenectomia não houve alteração das dosagens de imunoglobulinas nem diminuição do sistema complemento.

Adolescent , Adult , Female , Humans , Male , Middle Aged , Esophageal and Gastric Varices/surgery , Gastrointestinal Hemorrhage/etiology , Hypertension, Portal/surgery , Schistosomiasis mansoni/surgery , Splenectomy/methods , B-Lymphocytes/immunology , Esophageal and Gastric Varices/etiology , Esophageal and Gastric Varices/immunology , Follow-Up Studies , Gastrointestinal Hemorrhage/immunology , Gastrointestinal Hemorrhage/surgery , Hypertension, Portal/etiology , Hypertension, Portal/immunology , Immunoglobulins/blood , Immunoglobulins/immunology , Prospective Studies , Schistosomiasis mansoni/complications , Schistosomiasis mansoni/immunology , T-Lymphocytes/immunology , Treatment Outcome
Article in English | WPRIM | ID: wpr-36290


Infectious bursal disease (IBD) is an acute and highly contagious disease of young chickens caused by Birnavirus. Mortality of infected birds can be best prevented if injected with antibodies. The present study was an attempt to raise specific hyper-immune polyclonal antibodies against IBD virus in Pakistan. Commercial layers divided into four groups were injected with IBD vaccine subcutaneously according to four different treatment regimens. Eggs were collected daily and antibodies were purified from yolk with dextran sulphate. Titers of antibodies in serum and yolk were evaluated with enzyme linked immunosorbant assay and agar gel precipitation test. Antibody titers were significantly higher in yolk than serum. Eggs collected at 28 days post-vaccination had maximum antibody titers. Of treatment regimens, T3 was found to be most effective for hyperimmunization. Lyophilized antibodies stored at 4oC did not lose their activity till the end of experiment. IBD virus infected birds were injected with purified antibodies which induced 92% recovery as compared to control birds. The study implicates that the purified antibodies may be useful as a therapeutic agent to cure IBD infected birds.

Animals , Antibodies, Viral/blood , Birnaviridae Infections/immunology , Chickens , Egg Yolk/immunology , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Immunization/methods , Immunoglobulins/immunology , Immunotherapy/methods , Infectious bursal disease virus/immunology , Poultry Diseases/immunology , Precipitin Tests/veterinary , Viral Vaccines/immunology
Rev. Soc. Bras. Med. Trop ; 38(2): 137-141, mar.-abr. 2005. tab, graf
Article in Portuguese | LILACS | ID: lil-396328


O presente trabalho avaliou o perfil de anticorpos em amostras de soro de 37 pacientes com diagnóstico clínico confirmado ou compatível com leishmaniose tegumentar americana atendidos no Hospital de Clínicas da Universidade Federal de Uberlândia, MG. Os perfis das classes de imunoglobulinas e subclasses de IgG foram analisados pelo teste ELISA indireto, utilizando-se antígeno solúvel de Leishmania (Leishmania) amazonensis. A avidez dos anticorpos foi determinada pelo tratamento com uréia a 6 M, após incubação dos soros com o antígeno. Observou-se que 97 por cento, 94,6 por cento, 57,5 e 21,5 por cento das amostras testadas apresentaram anticorpos anti-Leishmania das classes IgE, IgG, IgA e IgM, respectivamente e, os perfis das subclasses de IgG demonstraram, IgG1>IgG3>IgG2>IgG4. Os anticorpos IgE anti-Leishmania de alta avidez corresponderam a 44,4 por cento. Por outro lado, IgG e IgA anti-Leishmania foram em sua maioria (62,8 e 47,8 por cento, respectivamente), de média avidez. A variação do perfil de isotipos, bem como a avidez das imunoglobulinas refletiu a complexidade da resposta imune humoral contra a leishmaniose tegumentar americana.

Humans , Animals , Male , Female , Adult , Middle Aged , Antibodies, Protozoan/blood , Immunoglobulin Isotypes/blood , Immunoglobulins/blood , Leishmania braziliensis/immunology , Leishmaniasis, Cutaneous/blood , Antibody Affinity , Biomarkers/blood , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G/blood , Immunoglobulin G/classification , Immunoglobulin G/immunology , Immunoglobulin Isotypes/immunology , Immunoglobulins/immunology , Leishmaniasis, Cutaneous/immunology