979 resultados para Immunoglobulin Isotypes


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Background: Cytosine-phosphate-guanosine oligodeoxynucleotide (CpG-ODN) has been used successfully to induce immune responses against viral and intracellular organisms in mammals. The main objective of this study was to test the effect of CpG-ODN on antigen presenting cells of young foals. Methods: Peripheral blood monocytes of foals (n = 7) were isolated in the first day of life and monthly thereafter up to 3 months of life. Adult horse (n = 7) monocytes were isolated and tested once for comparison. Isolated monocytes were stimulated with IL-4 and GM-CSF (to obtain dendritic cells, DC) or not stimulated (to obtain macrophages). Macrophages and DCs were stimulated for 14-16 hours with either CpG-ODN, LPS or not stimulated. The stimulated and non-stimulated cells were tested for cell surface markers (CD86 and MHC class II) using flow cytometry, mRNA expression of cytokines (IL-12, IFNα, IL-10) and TLR-9 using real time quantitative RT-PCR, and for the activation of the transcription factor NF-κB p65 using a chemiluminescence assay. Results: The median fluorescence of the MHC class II molecule in non-stimulated foal macrophages and DCs at birth were 12.5 times and 11.2 times inferior, respectively, than adult horse cells (p = 0.009). That difference subsided at 3 months of life (p = 0.3). The expression of the CD86 co-stimulatory molecule was comparable in adult horse and foal macrophages and DCs, independent of treatment. CpG-ODN stimulation induced IL-12p40 (53 times) and IFNα (23 times) mRNA expression in CpG-ODN-treated adult horse DCs (p = 0.078), but not macrophages, in comparison to non-stimulated cells. In contrast, foal APCs did not respond to CpG-ODN stimulation with increased cytokine mRNA expression up to 3 months of age. TLR-9 mRNA expression and NF-kB activation (NF-kB p65) in foal DCs and macrophages were comparable (p > 0.05) to adult horse cells. Conclusion: CpG-ODN treatment did not induce specific maturation and cytokine expression in foal macrophages and DCs. Nevertheless, adult horse DCs, but not macrophages, increased their expression of IL-12 and IFNα cytokines upon CpG-ODN stimulation. Importantly, foals presented an age-dependent limitation in the expression of MHC class II in macrophages and DCs, independent of treatment. © 2007 Flaminio et al; licensee BioMed Central Ltd.

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Venoms from snakes of the Bothrops genus are proteolytic, coagulant, hemorrhagic and nephrotoxic, causing edema, necrosis, hemorrhage and intense pain at the bite site, besides systemic alterations. Many adjuvants have been added to the venom used in the sensitization of antiserum-producer animals to increase antigenic induction and reduce the envenomation pathological effects. Gamma radiation from 60Co has been used as an attenuating agent of the venoms toxic properties. The main objective was to study, comparatively, clinical and laboratory aspects of goats inoculated with bothropic (Bothrops jararaca) venom, natural and irradiated from a 60Co source. Twelve goats were divided into two groups of six animals: GINV, inoculated with 0.5mg/kg of natural venom; and GIIV, inoculated with 0.5mg/kg of irradiated venom. Blood samples were collected immediately before and one, two, seven, and thirty days after venom injection. Local lesions were daily evaluated. The following exams were carried out: blood tests; biochemical tests of urea, creatinine, creatine kinase (CK), aspartate amino-transferase (AST) and alanine amino-transferase (ALT); clotting time; platelets count; and total serum immunoglobulin measurement. In the conditions of the present experiment, irradiated venom was less aggressive and more immunogenic than natural venom.

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The study evaluated the efficiency of diagnostic laboratory methods to detect anti-Toxoplasma gondii antibodies in paired serum and aqueous humour samples from experimentally infected pigs. 18-mixed breed pigs were used during the experiment; these were divided into two groups, G1 (infected group, n = 10) and G2 (uninfected group, n = 8). Infection was performed with 4 × 10 4 VEG strain oocysts at day 0 by the oral route in G1 animals. All pigs were euthanized at day 60, when retina, aqueous humour, and blood samples were collected. Anti-T. gondii antibody levels were assessed in serum (s) and aqueous humour (ah) by indirect immunofluorescence assay (IFA), modified agglutination test (MAT), m-ELISA (using crude membranes from T. gondii tachyzoites as antigen) and r-ELISA (using rhoptries from T. gondii tachyzoites as antigen). Polymerase chain reactions (PCR) of samples from the retina were performed by using Tox4 and Tox5 primers. Antibody titers of G1 animals ranged from 128 to 1024 and from 16 to 256 in serum and aqueous humour, respectively. There were differences in the correlation coefficients between IFA(s) × IFA (ah) (r = 0.62, P = 0.05), MAT(s) × MAT (ah) (r = 0.97, P < 0.0001); however, there was no significant difference between r-ELISA(s) × r-ELISA (ah) (r = 0.14, P = 0.7). Antibodies present in serum and aqueous humour recognized similar antigens. Samples of retina were positive by PCR in 30% (3/10) of infected pigs. G2 animals remained without antibody levels and were PCR negative throughout the experiment. These results suggest that the use of a combination of tests and immunoblotting for paired aqueous humour and serum samples could improve the sensitivity and specificity for the diagnosis of ocular toxoplasmosis. © 2007 Elsevier Ltd. All rights reserved.

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West syndrome is a severe epilepsy, occurring in infancy, that comprises epileptic seizures known as spasms, in clusters, and a unique EEG pattern, hypsarrhythmia, with psychomotor regression. Maturation of the brain is a crucial component. The onset is within the first year of life, before 12 months of age. Patients are classified as cryptogenic (10 to 20%), when there are no known or diagnosed previous cerebral insults, and symptomatic (80 to 90%), when associated with pre-existing cerebral damages. The time interval from a brain insult to infantile spasms onset ranged from 6 weeks to 11 months. West syndrome has a time-limited natural evolutive course, usually disappearing by 3 or 4 years of age. In 62% of patients, there are transitions to another age-related epileptic encephalopathies, the Lennox-Gastaut Syndrome and severe epilepsy with multiple independent foci. Spontaneous remission and remission after viral infections may occur. Therapy with ACTH and corticosteroids are the most effective. Reports about intravenous immunoglobulins action deserve attention. There is also immune dysfunction, characterized mainly by anergy, impaired cell-mediated immunity, presence of immature thymocytes in peripheral blood, functional impairment of T lymphocytes induced by plasma inhibitory factors, and altered levels of immunoglobulins. Changes in B lymphocytes frequencies and increased levels of activated B cells have been reported. Sensitized lymphocytes to brain extract were also described. Infectious diseases are frequent and may, sometimes, cause fatal outcomes. Increase of pro-inflamatory cytokines in serum and cerebrospinal fluid of epileptic patients were reported. Association with specific HLA antigens was described by several authors (HLA-DR7, HLA-A7, HLA-DRw52, and HLA-DR5). Auto-antibodies to brain antigens, of several natures (N-methyl-d-aspartate glutamate receptor, gangliosides, brain tissue extract, synaptic membrane, and others), were described in epileptic patients and in epileptic syndromes. Experimental epilepsy studies with anti-brain antibodies demonstrated that epileptiform discharges can be obtained, producing hyperexcitability leading to epilepsy. We speculate that in genetically prone individuals, previous cerebral lesions may sensitize immune system and trigger an autoimmune disease. Antibody to brain antigens may be responsible for impairment of T cell function, due to plasma inhibitory effect and also cause epilepsy in immature brains. © 2008 Bentham Science Publishers Ltd.

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Considered as one of the main agents of the tripanossomiases, Trypanosoma evansi causes a disease generically know as surra, with wide geographic occurence. This work has the aim to study the electrophoretic profile of the acute phase proteins of goats, experimentally infected with T. evansi. Ten crossbread female goats, around 4 months of age, clinically healthy and serum negative for the presence of antibodies anti-T. evansi (IFAT) were used. The animals were divided in two groups: six were inoculated (G1) intravenously with 2,38 × 10 6 tripomastigotes of T. evansi and four were kept as noninfected controls. The blood for serum was collected daily until the 14 days after inoculation (DAI), weekly up to the 98 th DAI and every two weeks up to the 364 th DAI. The serum proteins were separacted by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDSPAGE). Twenty-one proteins were found in the serum of the goats, eight were nominally identified; phosphorylase, transferrin, albumin, antitrypsin, acid glicoprotein, haptoglobin, hemoglobin, and light chain immunoglobulin.

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Autoimmune bullous dermatoses are diseases in which blisters and vesicles are the primary and fundamental types of skin lesion. Their classification is based on the location of the blister: intraepidermal and subepidermal. Patients produce autoantibodies against self-specific structures of the skin detectable by immunofluorescence techniques, immunoblotting and ELISA. Recent advances in molecular and cellular biology have brought to knowledge these self-antigens, against which patients are sensitized, and which are found in epidermis or in the dermo-epidermal junction. These are low incidence, but high morbidity diseases that may be fatal. The aim of this article is to review and describe the progress of four autoimmune vesiculobullous disorders: endemic pemphigus foliaceous (wild fire), pemphigus vulgaris, bullous pemphigoid and dermatitis herpetiformis. ©2009 by Anais Brasileiros de Dermatologia.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Background: Protein-calorie malnutrition (PCM) is the most common type of malnutrition. PCM leads to immunodeficiency and consequent increased susceptibility to infectious agents. In addition, responses to prophylactic vaccines depend on nutritional status. This study aims to evaluate the ability of undernourished mice to mount an immune response to a genetic vaccine (pVAXhsp65) against tuberculosis, containing the gene coding for the heat shock protein 65 from mycobacteria. Methods: Young adult female BALB/c mice were fed ad libitum or with 80% of the amount of food consumed by a normal diet group. We initially characterized a mice model of dietary restriction by determining body and spleen weights, hematological parameters and histopathological changes in lymphoid organs. The ability of splenic cells to produce IFN-gamma and IL-4 upon in vitro stimulation with LPS or S. aureus and the serum titer of specific IgG1 and IgG2a anti-hsp65 antibodies after intramuscular immunization with pVAXhsp65 was then tested. Results: Dietary restriction significantly decreased body and spleen weights and also the total lymphocyte count in blood. This restriction also determined a striking atrophy in lymphoid organs as spleen, thymus and lymphoid tissue associated with the small intestine. Specific antibodies were not detected in mice submitted to dietary restriction whereas the well nourished animals produced significant levels of both, IgG1 and IgG2a anti-hsp65. Conclusion: 20% restriction in food intake deeply compromised humoral immunity induced by a genetic vaccine, alerting, therefore, for the relevance of the nutritional condition in vaccination programs based on these kinds of constructs. © 2009 Ishikawa et al; licensee BioMed Central Ltd.

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The aim of this study was to determine the serum concentrations of immunoglobulin G, TP and the γ globulin electrophoretic fraction, as well as the enzymatic activities of GGT and ALP. This was done in order to explore the possibility of using changes in activities of these enzymes as indirect indicators of adequate humoral immunity and/ or failure of immune passive transfer in lambs. Pearson correlation was performed between variable of four groups of age during the first 30 days of life. Blood samples (191) from lambs from 21 different farms in Araçatuba region- São Paulo. The following tests were perfomed: radial immunodiffusion, spectrophotometry and electrophoresis to stain the amount of IgG, TP and γ globulin, respectively. GGT and ALP values were determinate using commercial kits. There was a statistically significant correlation between ALP and GGT. The same correlation was observed from TP, IgG and GGT. A positive γ globulin correlation was found between GGT, IgG and TP. ALP activity cannot be used as an indicator of immune passive transfer.

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Toxoplasma gondii is the causative intracellular protozoan of toxoplasmosis in human being and animals. Members of the Felidae family are considered the single definitive host for the infection; both wild and domestic cats are able to excrete oocysts in the environment. Wild cats maintained in captivity may serve as source of infection for other clinically susceptible animals in the same environment. The aim of this study was to determine the frequency of T. gondii IgG antibodies in 57 neotropical felids (1 Leopardus geoffroyi; 3 Puma yagouaroundi; 17 Leopardus wiedii; 22 Leopardus tigrinus; and 14 Leopardus pardalis) kept at the Bela Vista Biological Sanctuary, Itaipu Binacional, Southern Brazil, by the modified agglutination test (MAT) using titer 16 as cut-off point. Seropositivity was observed in 38/57 (66.67%; 95% CI 53.66-77.51%) samples, with higher frequency in ocelots (71.43%). Wild-caught felids were three times more likely to be infected when compared to zoo-born animals (P≤ 0.05) and age of wild-caught animals (P= 0.6892; 95% CI. = 0.7528-1.66) was not significant as a risk factor for the infection, the same occurring with zoo-born animals (P= 0.05; 95% CI. = 0.6267-24.052). These results suggest that, despite efforts to control T. gondii infection in zoo facilities, such as individual pens, hygiene monitoring, veterinary care and pre-frozen meat offered as food, non-domestic felids kept in captivity, particularly the wild-caught specimens, may be invariably exposed to infection due to other environmental sources. © 2010 Elsevier B.V.

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This work was conducted to verity the possibility to identify adult sheep that are resistant to parasites by using a parasitological marker (direct), immunological markers (indirect) or by the association of both types of markers. Twenty ewes were sampled monthly for blood and faeces, from July of 1998 to June of 1999. Faecal egg counts (FEC) was chosen as parasitological marker. The number of peripheral eosinophils, IgE and IgG anti-Haemonchus contortus were used as immunological markers. Sheep could be classified as resistant or susceptible by FEC. Both peripheral eosinophils and specific IgE data could be joined to FEC in order to identify resistant or susceptible animals. The number of peripheral eosinophils was the only immunological maker that was able to classify high and low FEC ewes in two different groups.

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Introduction: The autologous serum skin test (ASST) may suggest an autoimmune etiology in chronic urticaria (CU). A new laboratory technique called basophil activation test (BAT) has been currently employed for its diagnosis. Objective: To analyze ASST in relation to BAT as well as to evaluate interleukin 3 (IL3) receptors (CD123) and non-specific immunoglobulin G (IgG) autoantibodies bound to basophils in patients with chronic urticaria. Methods: We studied 33 adults with CU and mean age of 42.5 + 14 years. After stimulation by serum from patients with CU, CD63 expression on basophils from one atopic donor was analyzed by flow cytometry. Furthermore, we investigated CD123 and IgG autoantibody expressions. Results: The odds ratio (OR) between ASST and BAT was 1.00 (95% confidence interval [CI]: 0.22 to 4.5). The ASST for autoimmune CU diagnosis showed an accuracy of 54.5%, sensitivity of 66%, specificity of 33%, positive predictive value of 63%, and negative predictive value of 36%. There was no statistical difference between the studied groups as to mean non-specific IgG and CD123 expressions (for a p < 0.05). Discussion: This study demonstrated that ASST has low accuracy in the diagnosis of autoimmune CU. Concerning other analyzed aspects, there was no statistical difference between positive ASST and negative ASST. Conclusions: Due to insufficient studies in this area and the relevance of this issue, further investigation is required.

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Over the last decade, several studies were conducted on the gastrointestinal changes associated to chronic heart failure. This article presents a literature review on the physiopathology and clinical consequences of pathological digestive changes of heart failure patients. Structural and functional abnormalities of the gastrointestinal tract, such as edema of absorptive mucosa and intestinal bacterial overgrowth, have been leading to serious clinical consequences. Some of these consequences are cardiac cachexia, systemic inflammatory activation and anemia. These conditions, alone or in combination, may lead to worsening of the pre-existing ventricular dysfunction. Although currently there is no therapy specifically earmarked for gastrointestinal changes associated to heart failure, the understanding of digestive abnormalities is germane for the prevention and management of systemic consequences.

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Objective: To report the case of a child diagnosed with antiphospholipid syndrome associated with severe thrombocytopenia, and to review the literature on the subject. Case description: Child aged nine years and eight months old with severe thrombocytopenia associated with a positive anticardiolipin antibody. Data were collected by clinical history, physical examination, and laboratorial exams. Diagnosis was confirmed according to criteria established for the antiophospholipid syndrome, associated with the presence of the most common manifestations of the syndrome in children: livedo reticularis and thrombocytopenia. Comments: The antiphospholipid syndrome is an uncommon pediatric disease, and clinical manifestations such as decreased platelet number should be considered.

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This research was conducted with objective to evaluate the effect of different zinc (Zn) sources and doses in the diet for Santa Ines sheep. Forty lambs at weaning, with 18.4 kg of body weight were supplemented with three different sources of zinc (zinc oxide (ZnO), zinc amino acid and zinc proteinate) and three doses of zinc (200, 400 and 600 mg/kg DM) added to the basal diet. At every 28 days, animals were weighted and blood samples were collected for analyses of zinc (Zn), alkaline phosphatase and immunoglobulin G (IgG) and M (IgM). At the end of experiment, liver samples were collected for determination of the hepatic zinc levels. Zinc was analyzed with atomic absorption spectrophotometer, while phosphatase alkaline and immunoglobulins G and M were analyzed using Laborlab and Bioclin kits, respectively. There was no effect of diets on phosphatase alkaline levels and hepatic zinc, but there was difference in the plasmatic zinc levels and IgG and IgM levels. Based on the accumulation of hepatic zinc, the estimate of the zinc bioavailability, through the regression equation, showed that supplementation with organic and inorganic sources of zinc did not differ in the diet of Santa Ines sheep. © 2012 Sociedade Brasileira de Zootecnia.