106 resultados para leukocytes

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Galectin-1 (Gal-1) is important in immune function and muscle regeneration, but its expression and localization in adult tissues and primary leukocytes remain unclear. To address this, we generated a specific monoclonal antibody against Gal-1, termed alpha hGal-1, and defined a sequential peptide epitope that it recognizes, which is preserved in human and porcine Gal-1, but not in murine Gal-1. Using alpha hGal-1, we found that Gal-1 is expressed in a wide range of porcine tissues, including striated muscle, liver, lung, brain, kidney, spleen, and intestine. In most types of cells, Gal-1 exhibits diffuse cytosolic expression, but in cells within the splenic red pulp, Gal-1 showed both cytosolic and nuclear localization. Gal-1 was also expressed in arterial walls and exhibited prominent cytosolic and nuclear staining in cultured human endothelial cells. However, human peripheral leukocytes and promyelocytic HL60 cells lack detectable Gal-1 and also showed very low levels of Gal-1 mRNA. In striking contrast, Gal-1 exhibited an organized cytosolic staining pattern within striated muscle tissue of cardiac and skeletal muscle and colocalized with sarcomeric actin on I bands. These results provide insights into previously defined roles for Gal-1 in inflammation, immune regulation and muscle biology.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Resistance to chemotherapeutic drugs can be an obstacle to a successful treatment of cancer patients in part associated with individual response and differences in the DNA repair system. The Comet assay is an informative test to investigate DNA damage and repair in cells in response to a variety of DNA-damaging agents, including chemotherapeutic drugs. The aim of this study was to assess leukocytes damage after in-vitro cisplatin treatment and DNA repair action using the Comet assay in 20 patients with melanoma and 20 cancer-free individuals. Leukocytes` DNA damage before and after cisplatin treatment, in three different concentrations, was analyzed. The DNA repair capability was investigated after 1-5 h of in-vitro cells growing without cisplatin. The Comet score of the patients` basal DNA damage was higher than that observed in controls, but the difference was not statistically significant (P=0.85). Although both groups had similar Comet scores to all cisplatin concentrations tested and the DNA repair times, the basal DNA damage (P < 0.001) and cisplatin damages (P < 0.005) were statistically lower than the different repair times investigated. Considering the progressive increase in the Comet score due to repair time, the negative results here observed could be associated with the reduced cell culture incubation that should be better evaluated. Considering the mutagenic action of cisplatin on tumor cells and the importance of individual DNA repair mechanisms in the chemotherapeutic melanoma treatment, the peripheral leukocytes could be particularly useful as a tool for DNA repair response identified by the Comet assay. Melanoma Res 21:99-105 (C) 2011 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To study and characterize the in vivo effect of the lectin from Luetzelburgia auriculata seed on acute inflammation models. The lectin was purified from the crude saline extract by affinity chromatography on a guar-gum matrix. Native, heat-treated, and digested lectin was evaluated for anti-inflammatory activity by using peritonitis and paw edema models. The anti-inflammatory activity was characterized by intravital microscopy, nitric oxide production, and myeloperoxidase activity. The lectin exhibited anti-inflammatory activity (2 mg/kg) on both models, reducing local myeloperoxidase activity. Galactose or heat treatment (100A degrees C, 10 min) reduced anti-inflammatory action. Anti-inflammation involves the inhibition of adhesion and rolling of leukocytes along with augmentation of nitric oxide in serum. The lectin inhibited the edematogenic effect of histamine and prostaglandins (PGE2) but did not alter the chemoattractant effect of IL-8. The results indicate that this lectin is a potent anti-inflammatory molecule. Its effects engage diverse modulatory events.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purpose of the present trial was to compare the percentages of necrotic and apoptotic polymorphonuclear leukocytes (PMNL) in goat milk with low and high somatic cell count (SCC). Twenty eight milk samples were collected from 20 lactating goats, determined to be negative in bacteriological examination, and divided in three groups, according to their SCC: samples with SCC lower than 500 x 10(3) cells/mL; between 500 and 1500 x 10(3) cells/mL; and higher than 1500 x 10(3) cells/m L. SCC was performed in an automatic somatic cell counter. Apoptosis and necrosis were quantified using dual-color flow cytometry with fluorescein labeled annexin-V and propidium iodide (PI). Results of the present study showed a significant positive correlation between the percentage of the viable PMNL and milk SCC(r = 0.495, P=0.008), as well as a significant negative correlation between apoptotic PMNL and milk SCC(r = -0.486, P = 0.009). Results also pointed out lower PMNL viability rates due to higher apoptosis rates in milk samples with SCC lower than 5 x 10(5) cells/mL. (C) 2011 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We have previously demonstrated that mononuclear leukocytes from patients with sickle cell disease (SCD) release higher amounts of superoxide compared with normal controls. The aim of this study was to further study the NADPH oxidase system in these patients by investigating gene expression of NADPH oxidase components, phosphorylation of p47(phox) component, and the release of cytokines related to NADPH oxidase activation in mononuclear leukocytes from patients with SCD. gp91(phox) gene expression was significantly higher in monocytes from SCD patients compared with normal controls (P = 0.036). Monocytes from SCD patients showed higher levels of p47 phox phosphorylation compared with normal controls. INF-gamma release by lymphocytes from SCD patients was significantly higher compared with normal controls, after 48 h culture with phytohemagglutinin (P = 0.02). The release of TNF-alpha by monocytes from SCD patients and normal controls was similar after 24 and 48 h culture with lipopolysaccharide (P > 0.05). We conclude that monocytes from SCD patients show higher levels of gp91(phox) gene expression and p47(phox) phosphorylation, along with increased IFN-gamma release by SCD lymphocytes. These findings help to explain our previous observation showing the increased respiratory burst activity of mononuclear leukocytes from SCD patients and may contribute to inflammation and tissue damage in these patients.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background & aim: To compare the effect of fish oil-based (FO) lipid emulsions (LE) for parenteral administration with standard LE and a new FO containing LE composed of four different oils on the antigen presentation and inflammatory variables. Methods: Phytohemagglutinin (PHA) activated human mononuclear leukocytes were cultured with different LE - Control: without LE; SO: soybean oil; SO/FO: soybean and FO (4:1); MCT/SO: medium chain triglycerides and SO (1:1); MCT/SO/FO: MCT/SO and FO (4:1) and SMOF: a new LE containing FO. Cytokine production was evaluated by ELISA, the expression of antigen-presenting and co-stimulatory surface molecules were analyzed by flow cytometry and lymphocyte proliferation was assessed by H(3)-Thymidine incorporation, after tetanus toxoid-induced activation. Results: All LE decreased the HLA-DR and increased CD28 and CD152 expression on monocytes/macrophages and lymphocytes surface (p < 0.05). SO/FO and MCT/SO/FO decreased lymphocyte proliferation (p<0.05). All LE decreased IL-2 product ion, but this effect was enhanced with MCT/SO/FO and SMOF (p < 0.05). MCT/SOTO decreased IL-6 and increased IL-10, whereas SO had the opposite effect (p < 0.05). Conclusion: FO LE inhibited lymphocyte proliferation and had an anti-inflammatory effect. These effects seem to be enhanced when FO is mixed with MCT/SO. SMOF had a neutral impact on lymphocyte proliferation and IL-6 and IL-10 production.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work investigated the functional role of nuclear factor-kappa B (NF-kappa B) in respiratory burst activity and in expression of the human phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase genes CYBB, CYBA, NCF1, and NCF2. U937 cells with a stably transfected repressor of NF-kappa B (IKB alpha-S32A/S36A) demonstrated significantly lower superoxide release and lower CYBB and NCF1 gene expression compared with control U937 cells. We further tested Epstein-Barr virus (EBV)-transformed B cells from patients with anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID), an inherited disorderof NF-kappa B function. Superoxide release and CYBB gene expression by EDA-ID cells were significantly decreased compared with healthy cells and similar to cells from patients with X-linked chronic granulomatous disease (X91 degrees CGD). NCF1 gene expression in EDA-ID S321 cells was decreased compared with healthy control cells and similar to that in autosomal recessive (A47 degrees) CGD cells. Gel shift assays demonstrated loss of recombinant human p50 binding to a NF-kappa B site 5` to the CYBB gene in U937 cells treated with NF-kappa B inhibitors, repressor-transfected U937 cells, and EDA-ID patients cells. Zymosan phagocytosis was not affected by transfection of U937 cells with the NF-kappa B repressor. These studies show that NF-kappa B is necessary for CYBB and NCF1 gene expression and activation of the phagocyte NADPH oxidase in this model system.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

O uso de medicamentos antimamíticos específicos para vacas no período seco é indicado para prevenção de infecções na lactação seguinte. Não obstante, a ação das células envolvidas no período de secagem tem fundamental importância para a involução da glândula mamária e seu restabelecimento para a lactação subseqüente. A indisponibilidade de tais medicamentos para uso em cabras tem resultado na extrapolação do uso de produtos recomendados para vacas sem que se considerem as particularidades e diferenças anátomo-fisiológicas entre as espécies bovina e caprina. O presente estudo teve por objetivo avaliar a influência de cinco antimamíticos específicos para vacas secas sobre a função dos fagócitos provenientes de leite caprino. Para tal, fez-se o isolamento de células somáticas de 20 amostras de leite provenientes de 10 cabras lactantes, sem antecedentes de tratamento de mamite nos últimos 30 dias, sob condições higiênico-sanitárias de colheita e com resultados negativos ao cultivo microbiológico do leite. As células aderidas a lamínulas de vidro foram confrontadas com formulações contendo princípios ativos disponíveis no mercado como Gentamicina (M1), Cefalônio Anidro (M2), Ampicilina (M3), Cloxacilina Benzatínica (M4) e Cefapirina Benzatínica (M5). Avaliou-se, por microscopia, a fagocitose de partículas de Zymosan. As médias dos índices de fagocitose das células submetidas ao tratamento com M2 (15,12% ± 16,22), M3 (6,02% ± 7,96), M4 (4,54% ± 5,45) e M5 (2,47% ± 4,64) foram menores (p<0,001) que a média dos índices de fagocitose do grupo controle (40,67% ± 19,68). A média dos índices de fagocitose das células submetidas ao tratamento com M2 foi maior (p<0,05) que as médias dos tratamentos com M3, M4 e M5 enquanto estas foram estatisticamente iguais entre si. As amostras celulares submetidas ao medicamento M1 exibiram adesão insuficiente ou ausente às lamínulas, inviabilizando a avaliação da fagocitose por meio da técnica utilizada. Os resultados obtidos permitem concluir que os medicamentos estudados exerceram influência negativa sobre os fagócitos do leite, porém, esta interferência sobre as funções das células somáticas não pode por si só determinar o insucesso da terapia proposta para o período seco, pois deve ser considerada, outrossim, a eficácia do princípio ativo sobre o patógeno causador do processo infeccioso.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Chelonia mydas is a sea turtle that feeds and nests on the Brazilian coast and a disease called fibropapillomatosis is a threat to this species. Because of this, it is extremely necessary to determine a methodology that would enable the analysis of blood leukocyte function in these sea turtles. In order to achieve this aim, blood samples were collected from C. mydas with or without fibropapillomas captured on the São Paulo north coast. Blood samples were placed in tubes containing sodium heparin and were transported under refrigeration to the laboratory in sterile RPMI 1640 cell culture medium. Leukocytes were separated by density gradient using Ficoll-PaqueTM Plus, Amershan Biociences®. The following stimuli were applied in the assessment of leukocyte function: Phorbol Miristate-Acetate (PMA) for oxidative burst activity evaluation and Zymosan A (Saccharomyces cerevisiae) Bio Particles®, Alexa Fluor® 594 conjugate for phagocytosis evaluation. Three cell populations were identified: heterophils, monocytes and lymphocytes. Monocytes were the cells responsible for phagocytosis and oxidative burst.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background and Aims: Schistosomiasis is an intravascular parasitic disease associated with inflammation. Endothelial cells control leukocyte transmigration and vascular permeability being modulated by pro-inflammatory mediators. Recent data have shown that endothelial cells primed in vivo in the course of a disease keep the information in culture. Herein, we evaluated the impact of schistosomiasis on endothelial cell-regulated events in vivo and in vitro. Methodology and Principal Findings: The experimental groups consisted of Schistosoma mansoni-infected and age-matched control mice. In vivo infection caused a marked influx of leukocytes and an increased protein leakage in the peritoneal cavity, characterizing an inflamed vascular and cellular profile. In vitro leukocyte-mesenteric endothelial cell adhesion was higher in cultured cells from infected mice as compared to controls, either in the basal condition or after treatment with the pro-inflammatory cytokine tumor necrosis factor (TNF). Nitric oxide (NO) donation reduced leukocyte adhesion to endothelial cells from control and infected groups; however, in the later group the effect was more pronounced, probably due to a reduced NO production. Inhibition of control endothelial NO synthase (eNOS) increased leukocyte adhesion to a level similar to the one observed in the infected group. Besides, the adhesion of control leukocytes to endothelial cells from infected animals is similar to the result of infected animals, confirming that schistosomiasis alters endothelial cells function. Furthermore, NO production as well as the expression of eNOS were reduced in cultured endothelial cells from infected animals. On the other hand, the expression of its repressor protein, namely caveolin-1, was similar in both control and infected groups. Conclusion/Significance: Schistosomiasis increases vascular permeability and endothelial cell-leukocyte interaction in vivo and in vitro. These effects are partially explained by a reduced eNOS expression. In addition, our data show that the disease primes endothelial cells in vivo, which keep the acquired phenotype in culture.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: Leukotriene B(4) (LTB(4)) is a potent inflammatory mediator that also stimulates the immune response. In addition, it promotes polymorphonuclear leukocyte phagocytosis, chemotaxis, chemokinesis and modulates cytokines release. Regarding chemical instability of the leukotriene molecule, in the present study we assessed the immunomodulatory activities conferred by LTB(4) released from microspheres (MS). A previous oil-in-water emulsion solvent extraction-evaporation method was chosen to prepare LTB(4)-loaded MS. Results: In the mice cremasteric microcirculation, intraescrotal injection of 0.1 ml of LTB(4)-loaded MS provoked significant increases in leukocyte rolling flux, adhesion and emigration besides significant decreases in the leukocyte rolling velocity. LTB(4)-loaded MS also increase peroxisome proliferator-activated receptor-alpha (PPAR alpha) expression by murine peritoneal macrophages and stimulate them to generate nitrite levels. Monocyte chemoattractant protein-I (MCP-I) and nitric oxide (NO) productions were also increased when human umbilical vein and artery endothelial cells (HUVECs and HUAECs, respectively) were stimulated with LTB(4)-loaded MS. Conclusion: LTB(4)-loaded MS preserve the biological activity of the encapsulated mediator indicating their use as a new strategy to modulate cell activation, especially in the innate immune response.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objective: This study aims to investigate the effects of low-level laser therapy (LLLT) on muscle regeneration. For this purpose, the anterior tibialis muscle of 48 male Wistar rats received AlGaInP laser treatment (785 nm) after surgically-induced injury. Background Data: Few studies have been conducted on the effects of LLLT on muscle regeneration at different irradiation doses. Materials and Methods: The animals were randomized into four groups: uninjured rats (UN); uninjured and laser-irradiated rats (ULI); injured rats (IN); and injured and laser-irradiated rats (ILI). The direct contact laser treatment was started 24 h after surgery. An AlGaInP diode laser emitting 75 mW of continuous power at 785 nm was used for irradiation. The laser probe was placed at three treatment points to deliver 0.9 J per point, for a total dose of 2.7 J per treatment session. The animals were euthanized after treatment sessions 1, 2, and 4. Mounted sections were stained with hematoxylin and eosin and used for quantitative morphological analysis, in which the number of leukocytes and fibroblasts were counted over an area of 4480 mu m(2). The data were statistically analyzed by analysis of variance (ANOVA) and the Bonferroni t-test. Results: Quantitative data showed that the number of both polymorphonuclear and mononuclear leukocytes in the inflammatory infiltrate at the injury site was smaller in the ILI(1), ILI(2), and ILI(4) subgroups compared with their respective control subgroups (IN(1), IN(2), and IN(4)) for sessions 1, 2, and 4, respectively (p < 0.05). On the other hand, the number of fibroblasts increased after the fourth treatment session (p < 0.05). With regard to the regeneration of muscle fibers following injury, only after the fourth treatment session was it possible to find muscle precursor cells such as myoblasts and some myotubes in the ILI(4) subgroup. Conclusion: During the acute inflammatory phase, the AlGaInP laser treatment was found to have anti-inflammatory effects, reducing the number of leukocytes at the injury site and accelerating the regeneration of connective tissue.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: Adult-type hypolactasia, the physiological decline of lactase some time after weaning, was previously associated with the LCT -13910C>T polymorphism worldwide except in Africa. Lactase non-persistence is the most common phenotype in humans, except in northwestern Europe with its long history of pastoralism and milking. We had previously shown association of LCT -13910C>T polymorphism with adult-type hypolactasia in Brazilians; thus, we assessed its frequency among different Brazilian ethnic groups. Methods: We investigated the ethnicity-related frequency of this polymorphism in 567 Brazilians [mean age, 42.1 +/- 16.8 years; 157 (27.7%) men]; 399 (70.4%) White, 50 (8.8%) Black, 65 (11.5%) Brown, and 53 (9.3%) Japanese-Brazilian. DNA was extracted from leukocytes; LCT -13910C>T polymorphism was analyzed by PCR-restriction fragment length polymorphism. Results: Prevalence of the CC genotype associated with hypolactasia was similar (57%) among White and Brown groups; however, prevalence was higher among Blacks (80%) and those of Japanese descent (100%). Only 2 (4%) Blacks had TT genotype, and 8 (16%) had the CT genotype. Assuming an association between CC genotype and hypolactasia, and CT and TT genotypes with lactase persistence, 356 (62.8%) individuals had hypolactasia and 211 (37.2%) had lactase persistence. The White and Brown groups had the same hypolactasia prevalence (similar to 57%); nevertheless, was 80% among Black individuals and 100% among Japanese-Brazilians (P < 0.01). Conclusion: The lactase persistence allele, LCT -13910T, was found in about 43% of both White and Brown and 20% of the Black Brazilians, but was absent among all Japanese Brazilians studied.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Objectives: To analyze the effects of low-level laser therapy (LLLT), 670 nm, with doses of 4 and 7 J/cm(2), on the repair of surgical wounds covered by occlusive dressings. Background Data: The effect of LLLT on the healing process of covered wounds is not well defined. Materials and Methods: For the histologic analysis with HE staining, 50 male Wistar rats were submitted to surgical incisions and divided into 10 groups (n=5): control; stimulated with 4 and 7 J/cm(2) daily, for 7 and 14 days, with or without occlusion. Reepithelization and the number of leukocytes, fibroblasts, and fibrocytes were obtained with an image processor. For the biomechanical analysis, 25 rats were submitted to a surgical incision and divided into five groups (n=5): treated for 14 days with and without occlusive dressing, and the sham group. Samples of the lesions were collected and submitted to the tensile test. One-way analysis of variance was performed, followed by post hoc analysis. A Tukey test was used on the biomechanical data, and the Tamhane test on the histologic data. A significance level of 5% was chosen (p <= 0.05). Results: The 4 and 7J/cm(2) laser with and without occlusive dressing did not alter significantly the reepithelization rate of the wounds. The 7 J/cm(2) laser reduced the number of leukocytes significantly. The number of fibroblasts was higher in the groups treated with laser for 7 days, and was significant in the covered 4 J/cm(2) laser group. Conclusions: Greater interference of the laser-treatment procedure was noted with 7 days of stimulation, and the occlusive dressing did not alter its biostimulatory effects.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: Human Papillomavirus, HPV, is the main etiological factor for cervical cancer. Different studies show that in women infected with HPV there is a positive correlation between lesion grade and number of infiltrating macrophages, as well as with IL-10 higher expression. Using a HPV16 associated tumor model in mice, TC-1, our laboratory has demonstrated that tumor infiltrating macrophages are M2-like, induce T cell regulatory phenotype and play an important role in tumor growth. M2 macrophages secrete several cytokines, among them IL-10, which has been shown to play a role in T cell suppression by tumor macrophages in other tumor models. In this work, we sought to establish if IL-10 is part of the mechanism by which HPV tumor associated macrophages induce T cell regulatory phenotype, inhibiting anti-tumor activity and facilitating tumor growth. Results: TC-1 tumor cells do not express or respond to IL-10, but recruit leukocytes which, within the tumor environment, produce this cytokine. Using IL-10 deficient mice or blocking IL-10 signaling with neutralizing antibodies, we observed a significant reduction in tumor growth, an increase in tumor infiltration by HPV16 E7 specific CD8 lymphocytes, including a population positive for Granzyme B and Perforin expression, and a decrease in the percentage of HPV specific regulatory T cells in the lymph nodes. Conclusions: Our data shows that in the HPV16 TC-1 tumor mouse model, IL-10 produced by tumor macrophages induce regulatory phenotype on T cells, an immune escape mechanism that facilitates tumor growth. Our results point to a possible mechanism behind the epidemiologic data that correlates higher IL-10 expression with risk of cervical cancer development in HPV infected women.