10 research outputs found

    Congenital Transmission of Toxoplasma gondii After Experimental Reinfection With Brazilian Typical Strains in Chronically Infected Sheep

    Get PDF
    Toxoplasma gondii is a cause of congenital diseases, miscarriages and stillbirths in production animals. In Brazil, non-archetypal genotypes of the parasite may be related to severe disease. Experimental infection with T. gondii was studied in sheep to analyse congenital transmission-related parameters in reinfections with different Brazilian parasite strains. Thirteen T. gondii-seronegative sheep were orally infected with 2 × 103oocysts for the primary infection: G1 (4 animals) were inoculated with TgCatBr71 strain (Type BrI genotype) and G2 andG3 (5 and 4 animals, respectively) withTgCatBr60 strain (Type BrIII genotype). After chronification of infection, the animals were impregnated. A second infection was performed after 60 days of gestation. TheG1 andG3 animals were inoculated withTgCatBr60BrIII and the G2 animals withTgCatBr71 BrI oocysts. The effects of reinfection were compared with a control group (5 animals) through physical examination, ultrasound imaging and serology. Ovine experimental infections were evaluated using mouse bioassays, molecular analysis, serological tests, histopathology, and immunohistochemistry. No abortions occurred; a seropositive lamb and a mummified fetus from G2-BrIIIxBrI were produced. The vertical transmission rate detected in lambs from chronically infected sheep was 31.6% (6/19). It is demonstrated that reinfection and subsequent congenital transmission occured in one sheep with a primary Brl infection challenged with BrIII genotype of T. gondii. In a twin pregnancy from G2-BrIIIxBrI, congenital transmission from a latent infection was detected in both lambs. Congenital transmission could not be tracked in three lambs. Overall, previous T. gondii infection may fail to protect against congenital transmission from a reinfection and primary infection induced insufficient protection against vertical transmission which must be taken into account in decision-making for the use of seropositive animals as breeders. Similar trials with larger groups and contemplating host cellular immune response studies should be conducted to evaluate the actual impact of T. gondii reinfection involving different strains in sheep

    Liver transcriptomic networks reveal main biological processes associated with feed efficiency in beef cattle

    Get PDF
    Abstract\ud \ud Background\ud The selection of beef cattle for feed efficiency (FE) traits is very important not only for productive and economic efficiency but also for reduced environmental impact of livestock. Considering that FE is multifactorial and expensive to measure, the aim of this study was to identify biological functions and regulatory genes associated with this phenotype.\ud \ud \ud Results\ud Eight genes were differentially expressed between high and low feed efficient animals (HFE and LFE, respectively). Co-expression analyses identified 34 gene modules of which 4 were strongly associated with FE traits. They were mainly enriched for inflammatory response or inflammation-related terms. We also identified 463 differentially co-expressed genes which were functionally enriched for immune response and lipid metabolism. A total of 8 key regulators of gene expression profiles affecting FE were found. The LFE animals had higher feed intake and increased subcutaneous and visceral fat deposition. In addition, LFE animals showed higher levels of serum cholesterol and liver injury biomarker GGT. Histopathology of the liver showed higher percentage of periportal inflammation with mononuclear infiltrate.\ud \ud \ud Conclusion\ud Liver transcriptomic network analysis coupled with other results demonstrated that LFE animals present altered lipid metabolism and increased hepatic periportal lesions associated with an inflammatory response composed mainly by mononuclear cells. We are now focusing to identify the causes of increased liver lesions in LFE animals.The authors thank Fundação de Apoio a Pesquisa do Estado de São Paulo\ud (FAPESP) for financial support (process. numbers: 2014/02493-7; 2014/07566-\ud 2) and scholarship for PA Alexandre (2012/14792-3; 2014/00307-1). HN\ud Kadarmideen thanks EU-FP7 Marie Curie Actions – Career Integration Grant\ud (CIG-293511) for partially funding his time spent on this research. The authors\ud thank Dr. JF Medrano for the technical advice on RNAseq and experimental\ud design

    Proliferative response of peripheral blood mononuclear cells against autologous red blood cell membranes of dogs recently immunized

    No full text
    Embora faltem evidências diretas da relação causal entre a vacinação recente e o desenvolvimento da anemia hemolítica imunomediada (AHIM) em cães, pode ser identificada uma associação temporal entre elas. Constituem-se em objetivos deste trabalho avaliar: a presença de imunoglobulinas (IgG e IgM) e complemento (C3>) na superfície eritrocitária e o potencial do estímulo mitogênico de membranas eritrocitárias autólogas sobre os linfócitos periféricos de cães nos momentos pré-vacinal (imediatamente antes da vacinação com vacinas polivalente e antirrábica) e pós-vacinal (28 a 38 dias após a imunização). Vinte e um cães adultos e hígidos, machos e fêmeas, foram submetidos à anamnese, exame físico e avaliações laboratoriais nos dois momentos do estudo. O teste da antiglobulina direta (n=15) foi realizado com o reagente de Coombs polivalente, nas diluições de 1:2 a 1:8. A detecção de imunoglobulinas (IgG, IgM) e complemento (C3) na superfície de eritrócitos por citometria de fluxo (n=21) foi realizada utilizando anticorpos anti-IgG de cão produzido em ovelha cadeia pesada, anti-IgM produzido em cabra e anti-C3 de cão produzido em cabra, todos conjugados com fluoresceína de isotiocianato (FITC). As células mononucleares do sangue periférico foram isoladas por gradiende, marcadas com CFSE e estimuladas com Concanavalina A (ConA) e com membranas eritrocitárias autólogas em duas concentrações (ME1 e ME2). Foi utilizado o Índice de Proliferação (IP) como indicador da proliferação celular, obtido pela divisão das intensidades de fluorescência obtidas por citometria de fluxo das amostras basal e estimulada. As comparações das variáveis \"hemácias marcadas com anti-Ig/C3\" e \"IP de linfócitos\" foram realizadas utilizando-se o t-Student para amostras pareadas. As comparações dos IP de linfócitos frente aos diferentes antígenos (Con A, ME1 e ME2) foram realizadas por meio da ANOVA com medidas repetidas. Quando houve diferença significante entre os índices, foram realizadas comparações múltiplas (teste de Bonferroni). Foi considerado um nível de significância de 5%. Observou-se que os cães se encontravam em boas condições de saúde, nos dois momentos do estudo, com as variáveis hematológicas e bioquímicas mantidas próximas entre si e resultado do teste da antiglobulina direta negativo (n=21). A porcentagem de hemácias marcadas com IgG e IgM nos momentos pré-vacinal (1,06±0,49% e 1,42±1,59%) e pós-vacinal (0,83±0,56% e 1,35±1,71%) não foi alterada, com p=0,261 e p=0,699, respectivamente. A porcentagem de hemácias com C3 na superfície no momento pós-vacinação (0,40±0,38%) foi, em média, menor do que no momento pré-vacinação (0,71±0,33%), com p=0,019. Os índices de proliferação obtidos com a ConA, ME1 e ME2 no momento pré-vacinal (2,15±0,83; 1,03±0,07; 1,05±0,11) e pós- vacinal (2,13±0,58; 1,02±0,05; 1,02±0,05) não se modificaram, com p=0,935; p=0,845 e p=0,222, respectivamente. Em ambos os momentos, os índices de proliferação celular observados com o uso de ConA foram, em media, maiores do que os índices com ME1 e ME2 (p<0,001). A baixa porcentagem de hemácias com IgG, IgM ou C3 na superfície e a ausência de resposta proliferativa dos linfócitos quando estimulados com membranas eritrocitárias, indicam que, neste experimento, não houve nenhuma evidência de que o estímulo vacinal pudesse estar relacionado ao desenvolvimento da AHIM.Despite the lack of evidence regarding a causal link between recent vaccination and development of immune mediated hemolytic anemia (IMHA) in dogs, a temporal association between them has been identified in some cases. The aim of this study was to evaluate: the presence of immunoglobulins (IgG and IgM) and complement (C3) on the surface of red blood cells and the potential for mitogenic stimulation of peripheral lymphocytes against autologous red blood cell membranes on dogs at pre-vaccination (immediately prior to vaccination with polyvalent and anti-rabies vaccines) and post-vaccination (after 28 and 38 days after vaccination). Twenty-one healthy adult dogs (both males and females) were subjected to physical examination and complementary laboratory exams in the aforementioned two instances of the study (i.e. pre-vaccination and post-vaccination). Direct antiglobulin test (n=15) was performed using the polyvalent Coombs reagent in 1:2 to 1:8 dilutions. Immunoglobulins (IgG, IgM) detection and identification of complement (C3) on the surface of red blood cells were done by flow cytometry (n=21) using antibodies anti-dog IgG heavy chain produced in sheep, anti-dog IgM produced in goat and anti-dog C3 produced in goat - all in conjunction with fluorescein isothiocyanate (FITC). The peripheral blood mononuclear cells were isolated by gradient, labeled with CFSE and stimulated with concanavalin A (Con A) and autologous erythrocyte membranes in two concentrations (EM1 and EM2). The Proliferation Index (PI), used as an indicator of cell proliferation, was obtained by dividing the fluorescence intensities of basal and stimulated samples, both obtained by flow cytometry. A comparison was made between the variables \"labeled red blood cells with anti-Ig/C3\" and \"PI lymphocyte\" using the paired Student\'s t-test. Comparisons of PI lymphocytes to different antigens (Con A, EM1 and EM2) were performed using ANOVA of repeated measures. Whenever significant differences between the indices were found, multiple comparisons (Bonferroni test) were then performed. A 5% significance level was considered. At the two instances of the study, dogs were presented in good health status with both hematological and biochemical variables kept close together and negative results for direct antiglobulin test (n=21). The percentage of red blood cells labeled with IgG and IgM in the pre-vaccination (1.06±0.49% and 1.42±1.59%) and post-vaccination (0.83±0.56% and 1.35±1.71%) were kept similar, with p=0.261 and p=0.699, respectively. The percentage of erythrocytes with C3 on the surface at the time post-vaccination (0.40±0.38%) was on average lower than in the pre-vaccination (0.71±0.33%), p=0.019. The proliferation index obtained with ConA, ME1 and ME2 in the pre-vaccination (2.15±0.83, 1.03±0.07, 1.05±0.11) and post-vaccination (2.13±0.58, 1.02±0.05, 1.02±0.05) did not differ significantly, with p=0.935, p=0.845 and p=0.222, respectively. In both instances, rates of cell proliferation observed with the use of ConA were, on average, higher than the rates with ME1 and ME2 (p<0.001). The low percentage of erythrocytes with IgG, IgM or C3 on the surface and the absence of lymphocyte proliferative response when stimulated with erythrocyte membranes, indicate that, at least in this experiment, there is no evidence of any association between vaccine stimulation and development of IMHA in dogs

    Increased plasma lipids in triple-negative breast cancer and impairment in HDL functionality in advanced stages of tumors

    No full text
    Abstract The association between plasma lipids and breast cancer (BC) has been extensively explored although results are still conflicting especially regarding the relationship with high-density lipoprotein cholesterol (HDLc) levels. HDL mediates cholesterol and oxysterol removal from cells limiting sterols necessary for tumor growth, inflammation, and metastasis and this may not be reflected by measuring HDLc. We addressed recently diagnosed, treatment-naïve BC women (n = 163), classified according to molecular types of tumors and clinical stages of the disease, in comparison to control women (CTR; n = 150) regarding plasma lipids and lipoproteins, HDL functionality and composition in lipids, oxysterols, and apo A-I. HDL was isolated by plasma discontinuous density gradient ultracentrifugation. Lipids (total cholesterol, TC; triglycerides, TG; and phospholipids, PL) were determined by enzymatic assays, apo A-I by immunoturbidimetry, and oxysterols (27, 25, and 24-hydroxycholesterol), by gas chromatography coupled with mass spectrometry. HDL-mediated cell cholesterol removal was determined in macrophages previously overloaded with cholesterol and 14C-cholesterol. Lipid profile was similar between CTR and BC groups after adjustment per age. In the BC group, lower concentrations of TC (84%), TG (93%), PL (89%), and 27-hydroxicholesterol (61%) were observed in HDL, although the lipoprotein ability in removing cell cholesterol was similar to HDL from CRT. Triple-negative (TN) BC cases presented higher levels of TC, TG, apoB, and non-HDLc when compared to other molecular types. Impaired HDL functionality was observed in more advanced BC cases (stages III and IV), as cholesterol efflux was around 28% lower as compared to stages I and II. The altered lipid profile in TN cases may contribute to channeling lipids to tumor development in a hystotype with a more aggressive clinical history. Moreover, findings reinforce the dissociation between plasma levels of HDLc and HDL functionality in determining BC outcomes

    The Prolonged Activation of the p65 Subunit of the NF-Kappa-B Nuclear Factor Sustains the Persistent Effect of Advanced Glycation End Products on Inflammatory Sensitization in Macrophages

    No full text
    Advanced glycation end products (AGEs) prime macrophages for lipopolysaccharide (LPS)-induced inflammation. We investigated the persistence of cellular AGE-sensitization to LPS, considering the nuclear content of p50 and p65 nuclear factor kappa B (NFKB) subunits and the expression of inflammatory genes. Macrophages treated with control (C) or AGE-albumin were rested for varying intervals in medium alone before being incubated with LPS. Comparisons were made using one-way ANOVA or Student t-test (n = 6). AGE-albumin primed macrophages for increased responsiveness to LPS, resulting in elevated levels of TNF, IL-6, and IL-1beta (1.5%, 9.4%, and 5.6%, respectively), compared to C-albumin. TNF, IL-6, and IL-1 beta secretion persisted for up to 24 h even after the removal of AGE-albumin (area under the curve greater by 1.6, 16, and 5.2 times, respectively). The expressions of Il6 and RelA were higher 8 h after albumin removal, and Il6 and Abca1 were higher 24 h after albumin removal. The nuclear content of p50 remained similar, but p65 showed a sustained increase (2.9 times) for up to 24 h in AGE-albumin-treated cells. The prolonged activation of the p65 subunit of NFKB contributes to the persistent effect of AGEs on macrophage inflammatory priming, which could be targeted for therapies to prevent complications based on the AGE–RAGE–NFKB axis
    corecore