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The COVID-19 pandemic has imposed urgency to answer numerous questions about the control of viral infections and the dual immune response of protection of and damage to the host, with the purpose of finding specific and efficient treatments and strategies for prevention of infection. The association between severe cases of the disease and overactivation of the immune response has raised the hypotheses that the inflammatory response participates in the pathogenesis of SARS-CoV-2 infection, and that neutrophils are important effector cells of such response. In this sense, neutrophils are potential targets for pharmacological interventions to treat this infection. The present paper briefly describes the neutrophil biology and discusses the possible roles that neutrophils play in the pathogenesis of COVID-19, based on literature data.

Immune functions in teleosts are straightly influenced by environmental temperature. Low temperatures usually affect negatively the immune status of fishes favoring the incidence of diseases. Immune cells in fishes are protected from peroxidation by dietary vitamin E. Innate immune defenses of Piaractus mesopotamicus were evaluated in fish fed with diets supplemented with vitamin E for 45 days. The fish endured decreases in environmental fluctuations of temperature for 24 and 72 h. The most effects were observed at the 24th hour, in which the level of plasma cortisol increased independently of dietary supplement of vitamin E and a lessening of MNL and a raise of GL counting were observed in fish fed with supplemented diets. The lowest SL variation was observed in fish fed with the maximum level of vitamin E, but the dietary vitamin E decreased the HAC. However, the stressing condition increased HAC. Dietary vitamin E used in the present experimental conditions did not present remarkable effects on the immune frame of pacu to cope with environmental thermal fluctuations but other investigations concerning the vitamin half-life and its association with unsaturated dietary lipids seem to be fundamental.

Bothrops snake venoms contain biologically active components, including L-amino acid oxidases (LAAO) that induce significant leukocyte accumulation at inflammatory sites characterized by early neutrophil infiltration. As it remains unclear how snake venoms modulate neutrophil activation and chemokine production, here we examined whether Bothrops moojeni crude venom (BmV) and its LAAO (BmooLAAO-I) affect expression of the surface activation markers CD11b and CD66b, production of the chemokines CCL2/MCP-1, CCL5/RANTES, CXCL8/IL-8, CXCL9/MIG, and CXCL-10/IP-10, and activation of oxidative burst in human neutrophils. Cell viability, expression of activation markers, and chemokine production were assessed by flow cytometry, while the oxidative burst response was measured by chemiluminescence. BmV at 50 and 75 µg/mL reduced CXCL8/IL-8 (p < 0.001 and p < 0.01, respectively) and CCL2/MCP-1 production (p < 0.05), while BmooLAAO-I at the same concentrations reduced only CCL2/MCP-1 production (p < 0.01). These effects were accompanied by CD11b upregulation (p < 0.05 for 50 and 75 µg/mL BmV; p < 0.01 for 50 and 75 µg/mL BmooLAAO-I) and CD66b downregulation (p < 0.05 for 50 and 75 µg/mL BmV). Both BmV and BmooLAAO-I at concentrations ranging from 0.625 to 5 µg/mL suppressed the oxidative burst of neutrophils stimulated with phorbol 12-myristate 13-acetate, while BmooLAAO-I at 2.5 and 5 µg/mL also suppressed the neutrophil response stimulated with opsonized zymosan. Considering that neutrophils participate in the pathogenesis of autoimmune and inflammatory diseases, the findings reported herein indicate that BmV and BmooLAAO-I are potential immunomodulating agents.

Made available in DSpace on 2019-10-06T16:19:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The pathogenesis of sepsis involves complex systems and multiple interrelationships between the host and pathogen producing high mortality rates in various animal species. In this study, hematological disturbances, innate immunity and survival during the septic process in Piaractus mesopotamicus inoculated with Aeromonas hydrophila were studied. For this aim, fish blood samples were taken from control and infected groups 1, 3, 6, and 9 h post-inoculation (HPI). Leukogram showed reduction in the number of leukocytes and thrombocytes, followed by cessation of leukocyte chemotaxis 6 HPI and severe morphological changes in leukocytes and erythrocytes. At 3 HPI production of reactive oxygen species increased and at 6 HPI decreased. There was no change in serum lysozyme concentration and lytic activity of the complement system, despite the progressive increase in serum lytic activity and bacterial agglutination. Finally, the changes in clinical signs due to aeromonosis and increasing septicemia resulted in a reduction in survival to 57.14% after 36 HPI. It was possible concluded that these hematological and immune are crucial event in the worsening of sepsis in P. mesopotamicus, and these findings are utility for diagnosing and understanding the pathophysiology sepsis in pacu induced by A. hydrophila. Department of Veterinarian Pathology Faculty of Agrarian and Veterinarian Sciences São Paulo State University Unesp Institute of Biodiversity and Forests Federal University of Western Pará UFOPA Pará Aquaculture Center of UNESP, Jaboticabal Clinical Analysis Laboratory Veterinary Hospital Federal University of Uberlândia (UFU) Department of Clinical Toxicological and Bromatological Analyses Ribeirão Preto School of Pharmaceutical Sciences University of São Paulo (USP) Department of Veterinarian Pathology Faculty of Agrarian and Veterinarian Sciences São Paulo State University Unesp Aquaculture Center of UNESP, Jaboticabal FAPESP: 2011/20280-2 FAPESP: 2014/10231-2 CNPq: 441054/2014-5

Made available in DSpace on 2019-10-06T16:15:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Understanding how stress and corticosteroid modulates the innate immune response is one of the keys to improving productivity and reducing losses in intensive aquaculture. Thus, we investigated the effects of dietary corticosteroids (7 days; long-term exposure) and transport (4 h; short-term stress) on stress and innate immune response in pacu. For this end, fish were fed with diets containing dexamethasone (100 mg kg −1 ) or hydrocortisone (200 mg kg −1 ), followed by transport, and then were intraperitoneally inoculated with heat-killed Aeromonas hydrophila or PBS (sham-inoculation). Fish were sampled after a 7-day feeding period, immediately post-transport and 24 h post-transport and inoculation. The dietary treatment of corticosteroids decreased resting cortisol levels by inhibiting the production of cortisol on the hypothalamus pituitary interrenal-axis. Further, both corticosteroids reduced hematocrit, red blood cells, haemoglobin and hemolytic activity of the complement, while they increased glucose levels and serum lysozyme concentrations. The transport increased cortisol and glucose levels and reduced the humoral immune defenses such as serum lysozyme concentration and hemolytic activity of the complement system. Interestingly, the hemolytic activity of the complement system increased sharply in fish fed with corticosteroids immediately post-transport, when they had their HPI-axis partially suppressed by the corticosteroids. This finding suggests a stimulatory effect of the catecholamines released during the transport on the activity of the complement system. Our results are highly valuable to understanding the stress and innate immune responses to long-term exposure to corticosteroids and short-term stress in fish and may provide insights into how corticosteroids modulate the innate immune system. Universidade Estadual Paulista UNESP – Centro de Aquicultura (CAUNESP), Via de Acesso Prof. Paulo Donato Castelane, 14.884-900 Departamento de Análises Clínicas Toxicológicas e Bromatológicas Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade de São Paulo Universidade Estadual Paulista UNESP – Faculdade de Ciências Agrárias e Veterinárias, Via de Acesso Prof. Paulo Donato Castelane, 14.884-900 Universidade Estadual Paulista UNESP – Centro de Aquicultura (CAUNESP), Via de Acesso Prof. Paulo Donato Castelane, 14.884-900 Universidade Estadual Paulista UNESP – Faculdade de Ciências Agrárias e Veterinárias, Via de Acesso Prof. Paulo Donato Castelane, 14.884-900

Made available in DSpace on 2020-12-12T01:50:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Sepsis is a systemic process with multifactorial pathophysiology that affects most animal species. It is responsible for high rates of morbidity and mortality. This work aimed to study the biochemical and neuroendocrine changes of the sepsis process in Piaractus mesopotamicus after Aeromonas hydrophila inoculation analyzing changes in blood leukocyte and differences in neuroendocrine-biochemical modulation using RNA-seq. Fish showed hypercortisolemia, inhibition of glucose absorption, followed by hypocortisolemia and then hyperglycemia. Thyroid hormones (T3 and T4) showed immediate decrease in serum and T4 increased 6 h post-inoculation (HPI). Sepsis-induced hormonal alterations triggered changes in the metabolic pathways increasing protein and lipid catabolism, use of transient anaerobic glycolysis and liver injury. A reference transcriptome was constructed based on blood leukocytes from P. mesopotamicus. The assembly resulted in total 266,272 contigs with a N50 of 2786 bp. There was a reorganization of plasma membrane of leukocytes at the beginning of the septic process with increased expression of neuroendocrine receptors and with continuous flow of neurotransmitters, hormones and solutes with compensatory regulation at 6 HPI. Three and nine HPI seemed to be critical, the expression of a number of transcription factors was increased, including the modulatory DEGs related to glucocorticoid and thyroid hormones induced and suppressed (FDR < 0.05). Neuroendocrine modulation can regulate leukocytes and biochemical parameters of peripheral blood, being important sources for the study of the pathophysiology of sepsis. These finding highlights the importance of further studies focusing on biochemical-neuroendocrine changes in blood leukocytes and systemic sepsis. Department of Veterinarian Pathology Faculty of Agrarian and Veterinarian Sciences São Paulo State University, Unesp, Jaboticabal Institute of Biodiversity and Forests Federal University of Western Pará UFOPA Department of Genetics and Evolutionary Biology Institute of Biosciences São Paulo University USP Educational Foundation of Penápolis FUNEPE, Penápolis Aquaculture Center of UNESP, Jaboticabal Department of Animal Science São Paulo University USP ESALQ Clinical Analysis Laboratory Veterinary Hospital Federal University of Uberlândia UFU, Uberlândia Department of Clinical Analyses Toxicology and Food Sciences School of Pharmaceutical Sciences of Ribeirão Preto University of São Paulo USP Instituto del Mar del Perú IMARPE Department of Veterinarian Pathology Faculty of Agrarian and Veterinarian Sciences São Paulo State University, Unesp, Jaboticabal Aquaculture Center of UNESP, Jaboticabal FAPESP: 2011/20280-2 FAPESP: 2015/12143-6 CNPq: 441054/2014-5

Monocytes are key cells in the immune dysregulation observed during human immunodeficiency virus (HIV) infection. The events that take place specifically in monocytes may contribute to the systemic immune dysfunction characterized by excessive immune activation in infected individuals, which directly correlates with pathogenesis and progression of the disease. Here, we investigated the immune dysfunction in monocytes from untreated and treated HIV + patients and associated these findings with epigenetic changes. Monocytes from HIV patients showed dysfunctional ability of phagocytosis and killing, and exhibited dysregulated cytokines and reactive oxygen species production after M. tuberculosis challenge in vitro. In addition, we showed that the expression of enzymes responsible for epigenetic changes was altered during HIV infection and was more prominent in patients that had high levels of soluble CD163 (sCD163), a newly identified plasmatic HIV progression biomarker. Among the enzymes, histone acetyltransferase 1 (HAT1) was the best epigenetic biomarker correlated with HIV - sCD163 high patients. In conclusion, we confirmed that HIV impairs effector functions of monocytes and these alterations are associated with epigenetic changes that once identified could be used as targets in therapies aiming the reduction of the systemic activation state found in HIV patients.

In this study, we show that induced spawning causes stress, an intense loss of epithelia and immunosuppression, decreasing physical and humoral protection in fish, effects that were prevented or improved in fish bathed with Aloe vera. A. vera has several medicinal properties, including wound healing and immunostimulatory effects, which we observed in this study. Fish bathed with A. vera had a higher number of epidermal goblet cells and, in general, an improved wound healing rate compared with the control after induced spawning. These effects might be related to (1) the stimulation of leukocyte activity, represented here by the increased leukocyte respiratory activity triggered by A. vera (leukocytes are recognized as playing an important role in wound repair); (2) the antimicrobial properties of A. vera, which decrease wound infection and accelerate the healing process; and (3) several mechanisms that explain the healing effect of A. vera (increased collagen synthesis, rate of epithelialization, and anti-inflammatory and moisturizing effects). Our results also suggest that caution is necessary during the induced spawning process, especially during stripping, and A. vera bathing is recommended after intensive aquaculture operations.

Background The objective of this study was to evaluate the effect of three contraceptive pills containing ethinylestradiol (EE) (20 or 30 mcg) in combination with drospirenone (DRSP) and levonorgestrel (LNG) on plasma concentration of adhesion molecules vascular cell adhesion molecule -1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin. Study Design A cross-sectional study was conducted with 72 participants (18–30 years old) distributed into three groups that used oral contraceptives containing EE 20 or 30 mcg combined with DRSP 3 mg or EE 30 mcg/LNG 150 mcg for at least 6 months. The control group was comprised of nonusers of contraceptives. Soluble VCAM-1, soluble ICAM-1 and soluble E-selectin were evaluated by enzyme-linked immunosorbent assay. Results Compared to the control group, a significant decrease was found in VCAM-1 and ICAM-1 concentrations with use of DRSP/20 EE and LNG/30 EE. Conclusions DRSP/20 EE and LNG/30 EE induce favorable changes in endothelial function.

Chrysobalanus icaco L. is an underexplored plant found in tropical areas around the globe. Currently, there is no apparent information regarding the effects C. icaco fruits may exert in vivo or potential role in health promotion. This study aimed at providing evidence regarding the in vivo influence of this fruit on antigenotoxicity, antimutagenicity, and oxidative stress in rats. Male Wistar rats were treated with 100, 200, or 400 mg/kg body weight (bw)/d C. icaco fruit for 14 d. Doxorubicin (DXR, 15 mg/kg bw, ip) was used for DNA damaging and as an oxidant to generate reactive oxygen species (ROS). Genomic instability was assessed by the comet assay and micronucleus (MN) test, while antioxidant activity was determined by oxidative burst of neutrophils. Chrysobalanus icaco fruit polyphenols were quantified and characterized by high-performance liquid chromatography coupled to a diode array detector and tandem mass spectrometer (HPLC-DAD-MS/MS). The concentrations of 19 chemical elements were determined by inductively coupled plasma–mass spectroscopy (ICP-MS). Significant amounts of polyphenols, magnesium, and selenium were found in C. icaco fruit. This fruit displayed in vivo antioxidant activity against DXR-induced damage in rat peripheral blood neutrophils, antigenotoxicity in peripheral blood cells, and antimutagenicity in bone-marrow cells and peripheral blood cells. Correlation analyses between endpoints examined indicated that the mechanism underlying chemopreventive actions of C. icaco fruit was attributed to inhibition of NADPH oxidase complex manifested as low levels of DNA damage in animals exposed to DXR. Data indicate that phytochemicals and minerals in C. icaco fruit protect DNA against damage in vivo associated with their antioxidant properties.

Evaluation of the respiratory burst induced by receptors Fc R and CR was carried out in peripheral blood neu- trophils (PBN) in rheumatoid arthritis (RA) patients with active and inactive disease. Simultaneously, cooperation be- tween these receptors and their expression, PBN chemotaxis, and complement system systemic activity were also investi- gated. Neutrophils were stimulated with IC-IgG opsonized with normal human serum (NHS) or not, or with IC-IgG op- sonized with RA human serum (RAHS). ROS production was increased in neutrophils of patients with active or inactive RA stimulated of IC-IgG opsonized with NHS compared to the response of the cells mediated by ICIgG. However, there was poor Fc R/CR cooperation in these RA neutrophils, as indicated by decreased ROS production upon stimulation with IC-IgG opsonized with RAHS. In the case of active RA patients, neutrophils presented significantly higher CR1 and CR3 expression, as well as slight elevation in CD32 and CD16 expression. Positive correlations between Fc R and CR, com- plement alternative pathway activation, and increased RA serum chemotaxic activity were only detected in active RA pa- tients. Taken together, these results indicate that several abnormalities of the complement system exist at the systemic level, namely impaired membrane receptor cooperation, alternative pathway activation, and presence of pre-existing chemoattractant factors in the serum, as reflected by the neutrophil function in the particular case of active RA patients. All, these abnormalities may synergistically contribute to RA pathogenesis.

Background: Very few studies have investigated, in the elderly, the effect of rheumatic inflammatory states on phagocyte function and free radical production. The objective of this article is to evaluate phagocytosis by neutrophils and the production of nitric oxide (·NO) by monocytes in elderly women recruited among patients of the Brazilian Public Health System. Methods: Forty patients aged more than 60 years with rheumatic inflammatory diseases were studied. Phagocytosis was measured by flow cytometry. ·NO production was measured by the total nitrite assay and conventional inflammation markers were determined. Data were analyzed with the Mann–Whitney nonparametric test and P

To determine the relation between neutrophil function and the clinical characteristics of systemic lupus erythematosus (SLE), the superoxide anion (O2-) production by neutrophils, mediated by FcgammaR and FcgammaR/CR cooperation, was studied in 64 SLE patients classified according to their prevalent clinical manifestations. Three clinically distinct patterns were designated: (1) manifestations associated with the occurrence of cytotoxic antibodies (SLE-I group); (2) manifestations associated with circulating immune complexes (IC; SLE-II group), and (3) manifestations associated with IC and cytotoxic antibodies (SLE-III group). O2- production was evaluated by a lucigenin-dependent chemiluminescent assay in neutrophils stimulated with IC-IgG opsonized or not with complement. No difference in O2- production was observed when neutrophil responses from healthy controls were compared to the unclassified patients. However, when the SLE patient groups were considered, the following differences were observed: (1) SLE-I neutrophils showed lower O2- production mediated by the IgG receptor (FcgammaR) with the cooperation of complement receptors (FcgammaR/CR) than observed in the SLE-II, SLE-III, and healthy groups; (2) neutrophils from the SLE-II group showed a decreased [Formula: see text] production mediated by FcgammaR/CR compared to the SLE-III group, (3) SLE-III neutrophils produced more O(2)(-) than neutrophils from the SLE-II and control groups, and (4) CR showed inefficiency in mediating the O2- production by neutrophils from the SLE-I group. Comparative experiments on the kinetics of chemiluminescence (CL; Tmax and CLmax) disclosed differences only for the SLE-I group. Taken together, these results suggest that differences in oxidative metabolism of neutrophils mediated by FcgammaR/CR may reflect an acquired characteristic of disease associated with distinct clinical manifestations.

In this study, we assessed whether weight gain influenced the systemic lupus erythematosus (SLE) onset and/or outcome, and examined the role that reactive oxygen species (ROS) production by neutrophils played in the SLE onset and/or outcome. Female control (C57BL/6) and lupus-prone B6.MRL/lpr mice (CM and LPM, respectively) at 4 weeks old were fed standard diet or standard diet plus cafeteria diet during 12 weeks. SLE diagnosis relied on the presence of both antinuclear antibodies (ANA) and renal abnormalities. We found that the percentage of weight gain in CM and LPM increased as a function of the length of cafeteria diet feeding period, but it was not associated with energy intake. Cafeteria diet-fed CM and LPM at 8 and 12 weeks old were overweight, while CM and LPM at 16 weeks old were obese. Compared with standard diet-fed CM and LPM, cafeteria diet-fed CM and LPM exhibited elevated glucose and total cholesterol levels, and diminished triglycerides levels. Standard diet-fed 16-week-old LPM and cafeteria diet-fed 12-week-old LPM had nephritis, characterized by the increased interstitial infiltration of leukocytes. Cafeteria diet-induced weight gain rose the frequency of homogeneous and speckled ANA staining patterns in the 12- and 16-week-old LPM groups. Together, these results indicated that weight gain anticipated the SLE onset. In addition, neutrophils from cafeteria diet-fed 8-week-old LPM exhibited augmented ROS production capacity; in standard diet-fed LPM, such rise occurred only in the 16-week-old group. Thus, the neutrophil ROS production capacity was increased before the SLE onset and during its outcome. Overweight and obese CM and LPM displayed elevated levels of kidney, liver, heart, and spleen lipid peroxidation. In conclusion, cafeteria diet-induced weight gain is associated with the increased production of ANA and neutrophil-derived ROS, which may contribute to accelerate the SLE onset.

Os receptores para IgG fazem uma importante ligacao entre as respostas imunes humoral e celular. Estes receptores medeiam varias respostas biologicas tais como: fagocitose, endocitose, captura e clearance de imunocomplexos, citotoxicidade e liberacao de mediadores inflamatorios. Os Fcy R humanos pertencem a superfamilia das imunoglobulinas e tres classes principais destes receptores sao descritas, as quais apresentam varias isoformas. Estas moleculas diferem quanto a afinidade e especificidade para os isotipos de IgG, distribuicao celular, sinalizacao intracelular e pesos moleculares. Alem disso, o polimorfismo genetico e responsavel por variacoes entre os individuos. A diversidade estrutural e funcional dos Fcy R faz destas moleculas importantes alvos para a imunoterapia. A ativacao e desativacao de celulas efetoras via Fcy R pode ser explorada para o desenvolvimento de novas terapias para o câncer, doencas infecciosas e desordens auto-imunes. Esta revisao descreve detalhes estruturais e funcionais, relevância clinica e alguns usos terapeuticos dos Fcy R.

We have investigated the individual role of FcgammaR and CR, as well as their cooperation, in mediating the oxidative burst and degranulation of neutrophils of Brazilian systemic lupus erythematosus (SLE) patients. Neutrophils were stimulated with the immune complexes (IC)-IgG or -F(ab')2, opsonized or not with normal or SLE human serum. The oxidative burst was decreased in neutrophils of active SLE patients compared to healthy controls when this response was mediated by FcgammaR and/or CR, while the degranulation was unaffected. The SLE hypocomplementemia did not affect the oxidative burst mediated only by CR. FcgammaRII and CR1 expression on neutrophils of active SLE patients was reduced, while the expression of FcgammaRIII and CR3 was unaffected. These results suggest that the different FcgammaR and CR may be involved or cooperate in different ways in the mediation of the oxidative burst and the degranulation. Moreover, the decreased oxidative burst of neutrophils of active SLE patients may not depend only on SLE hypocomplementemia for IC opsonization. These observations are directed at the understanding of how each of these immune system components (FcgammaR, CR and complement) influences the precise biological neutrophil responses both in physiological and pathological conditions. Since the Brazilian population comprises many races, these results are important because they are directed at a specific population of SLE patients.

In this study, we aimed to investigate whether the distribution of the FcγRIIa and FcγRIIIb polymorphisms determines susceptibility to systemic lupus erythematosus (SLE) and acts as predictors of SLE clinical manifestations in the Brazilian patients. A total of 157 patients that fulfilled the American College of Rheumatology classification criteria for SLE and 160 healthy volunteers were included in this study. FCGR2A and FCGR3B genotypes were determined by polymerase chain reaction-based allotyping methods with allele-specific primers; the clinical features were obtained from the patients' official medical records. In the case of FcγRIIa polymorphism, it was observed association of the allele FCGR2A-R-131 (p = 0.02, odds ratio (OR)=1.44) and genotype RR-131 (p = 0.03, OR = 2.09) with SLE. These associations were higher with allele (p 0.01, OR = 1.67) as well genotype (p = 0.01, OR = 2.85) when lupus nephritis was considered. In contrast, the allele FCGR2A-H-131 was associated with susceptibility to arthritis and anti-DNA antibodies (p = 0.05 for both). As for FcγRIIIb polymorphism, skewing did not differ significantly between patients and controls, however the genotype FCGR3B*02*02 was associated with susceptibility to arthritis (p = 0.02) and malar rash (p = 0.03), but no association with nephritis was found. The results demonstrate that FcγRIIa polymorphism is associated with susceptibility to SLE in Brazilian patients, whereas for FcγRIIIb polymorphism no association was found. However, notably, both polymorphisms present allelic variants that influence the clinical manifestations and may contribute to the pathogenesis of the disease. In addition, to our knowledge, this is the first study considering the frequency of FcγRIIIb polymorphism in Brazilian SLE patients.

Considering that human neutrophil FcγRIIa and FcγRIIIb receptors interact synergistically with CR3 in triggering neutrophil functional responses, allelic polymorphisms in these receptors might influence such interactions. We assessed whether FcγRIIIb polymorphisms affect FcγR/CR cooperation in mediating the neutrophil oxidative burst (OB), in particular the FcγRIIIb/CR3 cooperation that occurs via lectin-saccharide-like interactions. The OB of human neutrophil antigen (HNA)-1a-, HNA-1b-, and HNA-1a/-1b-neutrophils stimulated with immune complexes, opsonized or not with serum complement, was measured by the luminol-enhanced chemiluminescence assay. Compared with HNA-1a-neutrophils, HNA-1b-neutrophils exhibited reduced FcγR-stimulated OB, but increased FcγR/CR-stimulated OB. It suggests that (i) FcγR and CR cooperate more effectively in HNA-1b-neutrophils, and (ii) the HNA-1b allotype influences the FcγRIIIb cooperation with FcγRIIa, but not with CR3. HNA-1a- and HNA-1b-neutrophils exhibited similar OB responses elicited via CR3 alone or via FcγR/CR-independent pathways. In addition, the level of FcγRIIIb, FcγRIIa, and CR3 expression did not differ significantly among the neutrophil groups studied. Together, these results demonstrate that the HNA-1b allotype influences the functional cooperation between FcγRIIIb and FcγRIIa, and suggest that the difference in the glycosylation pattern between HNA-1a and HNA-1b does not affect the FcγRIIIb cooperation with CR3.

Immune responses mediated by complement receptors (CR) are impaired in patients with systemic lupus erythematosus (SLE). Regarding CR3 (CD11b/CD18), the CD11b subunit is encoded by the ITGAM gene and a single nucleotide polymorphism (G230A; rs1143679) in ITGAM changes an arginine to a histidine at position 77 (R77H). We assessed whether the variant R77H, rs1143679 within ITGAM, is associated with the risk to developing SLE and the clinical manifestations of Brazilian SLE patients.The rs1143679 was genotyped by SSP-PCR in 157 patients with SLE and 147 healthy individuals. Clinical and laboratorial manifestations were obtained from the official medical records according the criteria of the American College of Rheumatology.The 77H variant was associated with susceptibility to SLE (OR=1.8); the frequencies of the minor allele A were 0.25 (SLE) and 0.15 (healthy) (p0.01). In addition, the minor allele A was associated with lupus nephritis (p=0.02) and antiphospholipid antibodies (p=0.04).These results showed that the rs1143679 variant is also associated with the risk to SLE in our population and with the risk to specific clinical manifestations, as nephritis and presence of antiphospholipid antibodies. These results may have implications for discussing the association of this polymorphism with the IC deposition in SLE.

Glucocorticoids have been used in the treatment of a variety of inflammatory processes including autoimmune diseases. However, the influence of low-dose glucocorticoids on the respiratory burst activity of neutrophils has not been studied. The aim of this work was to study the effect of treatment with low-dose prednisone on the oxidative burst of rat peripheral blood neutrophils. Wistar male rats were treated with prednisone by gavage (28, 87 or 257 microg/animal/day) for 7 or 15 days. These doses are equivalent to 10, 30 or 90 mg/adult human ( approximately 70 kg)/day, respectively. Sera from normal rats were used to opsonize zymosan (opZy). Neutrophils (1x10(5)) were stimulated by opZy and the oxidative burst of control or treated rat cells was measured by luminol-dependent chemiluminescence (CL). Prednisone did not affect the CL of rat neutrophils for either period of treatment, or any studied doses, when compared with controls. These results suggest that the low-dose prednisone has no effect on the oxidative burst mediated by complement receptors during the rat neutrophil phagocytosis of complement-opZy.

O sistema complemento desempenha um papel importante no transporte e eliminação de imunocomplexos (IC) circulantes. No entanto, existem circunstâncias em que os mecanismos envolvidos não são eficientes, favorecendo a deposição dos IC em órgãos específicos. Tais complexos depositados estimulam a fagocitose pelos polimorfonucleares neutrófilos, com conseqüente produção de radicais de oxigênio e liberação de enzimas lisossomais, e contribuem para a lesão tecidual local. Nesta revisão, damos ênfase ao papel do complemento, bem como dos neutrófilos, na patogênese das doenças por imunocomplexos.

Oreochromis niloticus bred in net cages were supplemented with cell wall of Saccharomyces cerevisiae (Sc) (0.3%) or chromium carbochelate (Cr) (18 mg/kg of feed) or in association (Sc + Cr), for 90 days. After this period, acute inflammation was induced in the swim bladder by inoculation of 3 × 10(8) CFU of inactivated Streptococcus agalactiae, and another group received 0.65% saline solution (control). Twelve, 24, and 48 h after stimulation, the inflammation was evaluated through total and differential counting of accumulated cells, and through leukocyte respiratory burst in the blood, cortisolemia, glycemia and serum lysozyme concentration. The results showed that there were greater total numbers of cells in the exudate of fish inoculated with inactivated bacterium than in those injected with saline solution, with predominance of lymphocytes, thrombocytes, macrophages and granulocytes. Tilapia supplemented with Cr presented increased total numbers of cells with significant accumulation of lymphocytes and reductions in cortisolemia and glycemia, but the different treatments did not have any influence on leukocyte respiratory burst or serum lysozyme concentration. Tilapia supplemented with Sc and the Cr + Sc association did not present significant changes to the variables evaluated, despite higher accumulation of lymphocytes in the inflammatory exudate from fish treated with Sc. The results indicate that tilapia bred in net cages and supplemented with Cr presented higher total accumulation of cells at the inflammatory focus, thus indicating an increase in the inflammatory response induced by the bacterium, probably due to the reduction in cortisolemia and higher glucose consumption. Thus, supplementation with Cr had beneficial action, which facilitated development of acute inflammation induced by the bacterium, but did not affect neither leukocyte respiratory burst in the blood nor serum lysozyme concentration.

Purpose: Evaluating the concentration of the�lipoproteins HDL, LDL, VLDL, triglycerides and total cholesterol in the serum of women who use oral combined contraceptives containing anti-androgenic progestogen in comparison to control group. Method: Cross-sectional study developed with 47 women (18 to 30 years), distributed into two groups of patients who used oral contraceptive drugs containing 20 or 30 ?g de Ethinylestradiol (EE) combined to Drospirenone (DRSP), compared to a control group. The serum levels of lipids (Total cholesterol, Triglycerides and HDL) were quantified through Trinder�s method. The levels of LDL and VLDL were obtained through mathematical formulas. Results: In the users of DRSP/30EE there was an increase in the levels of total cholesterol, triglycerides, HDL and VLDL in relation to control group. In the users of DRSP/20EE, there was an increase in the levels of total cholesterol and HDL. Conclusion: The anti-androgenic progestogen drospirenone was not effective to counterbalance the beneficial effect of the�estrogen on the levels of the lipoprotein HDL.

SUMMARYToxoplasma gondiistimulates a potent pro-inflammatory response and neutrophils are involved in early infection. Galectin-3 (Gal-3) is an endogenous modulator of inflammatory processes and anti-infective agents, but its interaction with neutrophils inT. gondiiinfection is still unclear. Here, we evaluated the role of Gal-3 in peritoneal inflammation, reactive oxygen species (ROS) production by neutrophils and survival, afterin vivo T. gondiiinfection with virulent RH strain, using Gal-3 deficient and wild type mice. Animals were inoculated with thioglycollate or tachyzoites, and peritoneal cells were harvested for analysis of the influx of leukocytes. Neutrophils were isolated from peritoneal exudates from infected mice and stimulated with phorbol myristate acetate (PMA) to evaluate ROS production by luminol-dependent chemiluminescence assay. Our results showed that: (1) Gal-3 upregulates peritoneal inflammation, with enhanced recruitment of neutrophils and lymphocytes after thioglycollate stimulation, but does not influence the enhanced neutrophil influx after earlyT. gondiiinfection; (2) Gal-3 upregulates ROS generation by inflammatory peritoneal neutrophils from infected mice, but downregulates its production in non-infected mice and (3) Gal-3 does not influence the survival of mice after infection with the virulentT. gondiistrain. In conclusion, Gal-3 is essential for ROS generation by neutrophils in the initial acute phase ofT. gondiiinfection and this phenomenon may constitute an attempt to control parasite growth duringin vivoinfection with theT. gondiivirulent strain.

Made available in DSpace on 2015-11-03T15:29:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-08-01. Added 1 bitstream(s) on 2015-11-04T10:14:49Z : No. of bitstreams: 1 S1519-69842014000300698.pdf: 1767980 bytes, checksum: e13401c991d40d349a5ca6ce478836c4 (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Os efeitos da β-glucana sobre as respostas imunes inatas e a sobrevivência foram estudados em pacu experimentalmente infectado com Aeromonas hydrophila. Peixes alimentados com dietas contendo 0,1% e 1% de β-glucana foram injetados com 1 × 108 CFU de A. hydrophila após 7 dias de alimentação. A sobrevivência de peixes foi maior nos dois grupos tratados em comparação ao grupo controle (26,7% e 21,2%, respectivamente). A atividade respiratória de leucócitos e a atividade hemolítica do complemento – via alternativa estavam elevadas após desafio bacteriano independentemente da concentração de β-glucana. A atividade de lisozima foi maior após a infecção e mostrou um aumento gradual de acordo com a concentração do imunoestimulante. Observou-se um aumento significativo na contagem de leucócitos totais após o desafio bacteriano e influência de β-glucana. A mesma resposta foi observada para trombócitos, linfócitos, eosinófilos, leucócito PAS positivo e monócitos. Com exceção de neutrófilos, que diminuíram frente ao mais alto nível do imunoestimulante e não se alteraram após a infecção, as outras células aumentaram após a exposição à A. hydrophila. A β-glucana não afetou os níveis de proteína total do soro, que aumentaram após o desafio bacteriano. Conclui-se que a administração de β-glucana em pacu pode aumentar a proteção contra A. hydrophila, por alterações nas respostas imunes de não-específicas. Effects of beta-glucan on innate immune responses and survival were studied in pacu experimentally infected with Aeromonas hydrophila. Fish fed diets containing 0, 0.1% and 1% beta-glucan were injected with A. hydrophila. beta-glucan enhanced fish survival in both treated groups (26.7% and 21.2% of the control, respectively). Leukocyte respiratory burst and alternative complement pathway activities were elevated after bacterial challenge regardless the beta-glucan concentration. Lysozyme activity was higher after infection and showed a gradual increase as beta-glucan concentration increased. A significant elevation in WBC count was observed either after bacterial challenge or by influence of beta-glucan separately. The same response was observed in the number of thrombocytes, lymphocytes, eosinophils, LG-PAS positive cell and monocytes. It can be concluded that feeding pacu with beta-glucan can increase protection against A. hydrophila, due to changes in non-specific immune responses. Universidade de São Paulo, Faculdade de Ciências Farmacêuticas de Ribeirão Preto Universidade Estadual Paulista, Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal Universidade Estadual Paulista, Departamento de Zootecnia, Faculdade de Ciências Agrárias e Tecnológicas de Dracena Universidade Estadual Paulista, Centro de Aquicultura da Unesp de Jaboticabal

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:52Z No. of bitstreams: 1 S1516-35982012000200001.pdf: 193560 bytes, checksum: 31b88fe3ed171fa971fa6c738b1259a6 (MD5) Made available in DSpace on 2013-08-22T19:07:52Z (GMT). No. of bitstreams: 1 S1516-35982012000200001.pdf: 193560 bytes, checksum: 31b88fe3ed171fa971fa6c738b1259a6 (MD5) Previous issue date: 2012-02-01 Made available in DSpace on 2013-09-30T17:42:07Z (GMT). No. of bitstreams: 2 S1516-35982012000200001.pdf: 193560 bytes, checksum: 31b88fe3ed171fa971fa6c738b1259a6 (MD5) S1516-35982012000200001.pdf.txt: 21853 bytes, checksum: 835852dd72b4563d54362a3ed7180191 (MD5) Previous issue date: 2012-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:12:40Z No. of bitstreams: 2 S1516-35982012000200001.pdf: 193560 bytes, checksum: 31b88fe3ed171fa971fa6c738b1259a6 (MD5) S1516-35982012000200001.pdf.txt: 21853 bytes, checksum: 835852dd72b4563d54362a3ed7180191 (MD5) Made available in DSpace on 2014-05-20T13:12:40Z (GMT). No. of bitstreams: 2 S1516-35982012000200001.pdf: 193560 bytes, checksum: 31b88fe3ed171fa971fa6c738b1259a6 (MD5) S1516-35982012000200001.pdf.txt: 21853 bytes, checksum: 835852dd72b4563d54362a3ed7180191 (MD5) Previous issue date: 2012-02-01 The objective of this study was to evaluate the methodology to establish the hemolytic activity of alternative complement pathway as an indicator of the innate immunity in Brazilian fish pacu (Piaractus mesopotamicus), in addition to verifying the influence of β-glucan as an immunostimulant. Fish were fed with diets containing 0, 0.1 and 1% β-glucan, during seven days, and then inoculated with Aeromonas hydrophila. Seven days after the challenge, they were bled for serum extraction. The methodology consisted of a kinetic assay that allows calculating the required time for serum proteins of the complement to promote 50% lysis of a rabbit red blood cell suspension. The method developed in mammals was successfully applied for pacu and determined that the hemolytic activity of the proteins of the complement system (alternative pathway) increased after the pathogen challenge, but was not influenced by the β-glucan treatment. Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista Faculdade de Zootecnia Universidade de São Paulo Faculdade de Ciências Farmacêuticas de Ribeirão Preto Toxicológicas e Bromatológicas Universidade Estadual Paulista Centro de Aquicultura Universidade Estadual Paulista Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista Faculdade de Zootecnia Universidade Estadual Paulista Centro de Aquicultura

Liposomes have been employed as potential drug carriers. However, after their in vivo administration, they can be destabilized by proteins of complement system, contributing to the clearance of vesicles from blood circulation. Antioxidant flavonoids such as quercetin have been reported to be beneficial to human health, but their low water solubility and bioavailability limit their enteric administration. Therefore, the development of appropriate flavonoid-carriers could be of great importance to drug therapy. The aim of the present study was to evaluate the activation of human complement system proteins by liposomes composed of soya phosphatidylcholine (SPC) and cholesterol (CHOL) or cholesteryl ethyl ether (CHOL-OET) loaded with quercetin or not. The consumption of complement, via classical (CP) and alternative (AP) pathways, by different vesicles was evaluated using a hemolytic assay and quantitative determination of iC3b and natural antibodies deposited on empty liposomal surfaces by ELISA. The main results showed that empty liposomes composed of large amounts of CHOL consumed more complement components than the others for both CP and AP. Furthermore, replacement of CHOL with CHOL-OET reduced complement consumption via both CP and AP. Incorporation of quercetin did not change CP and AP consumption. Deposition of iC3b, IgG and IgM in vesicles composed of SPC:CHOL-OET at a molar ratio of 1.5:1 was lower compared to the others. Taken together, these observations suggest that liposomes composed of SPC:CHOL-OET at a molar ratio of 1.5:1 are the most appropriate among the vesicles studied herein to be used as a drug carrier system in further investigations.

Iron and oxidative stress have a regulatory interplay. During the oxidative burst, phagocytic cells produce free radicals such as hypochlorous acid (HOCl). Nevertheless, scarce studies evaluated the effect of either iron deficiency anemia (IDA) or anemia of chronic disease (ACD) on phagocyte function in the elderly. The aim of the present study was to determine the oxidative burst, phagocytosis, and nitric oxide (•NO) and HOCl, reactive species produced by monocytes and neutrophils in elderly with ACD or IDA. Soluble transferrin receptor, serum ferritin, and soluble transferrin receptor/log ferritin (TfR-F) index determined the iron status. The study was constituted of 39 patients aged over 60 (28 women and 11 men) recruited from the Brazilian Public Health System. Oxidative burst fluorescence intensity per neutrophil in IDA group and HOCl generation in both ACD and IDA groups were found to be lower (p

Hypocomplementaemia and low expression of CR1 on erythrocytes (E) of patients with systemic lupus erythematosus (SLE) are associated with defective clearance of circulating immune complexes (IC) and so they may have pathogenic significance. Here, we investigated whether the reduced CR1/E in SLE patients per se might affect the binding of IC to CR1/E. First, we analysed the expression of CR1 on E of active (n = 30) and inactive (n = 34) SLE patients using a FITC-conjugated mouse anti-CR1 monoclonal antibody E11 and flow cytometry. Both groups of patients had a significantly reduced CR1/E expression compared with healthy controls (n = 40). It was also observed that the number of E bearing CR1 was reduced in both groups of SLE patients studied. Second, we determined the functional activity of CR1/E by measuring the binding to E of FITC-bovine serum albumin (BSA)/rabbit anti-BSA complexes, formed at equivalence, which were opsonized with complement from normal human serum (NHS). On the other hand, we did not find differences between the patient and control groups in the ability of E to bind IC/NHS. There was also a positive correlation between the CR1/E expression and the number of E bearing CR1 in control and inactive SLE groups, which was not observed in the group of active SLE patients. Considering the involvement of low levels of complement and CR1/E expression on complex processing, in this in vitro model the results show that an effective coating of the complexes with complement is sufficient to bind them preferentially to CR1 over normal levels of receptor expression.

When neutrophil phagocytes are stimulated by IgG containing immune complexes (IgG-IC), with or without the participation of the complement system, they show a sharp increase in oxygen uptake and begin to release large quantities of superoxide anions (O2-) and hydrogen peroxide (H2O2) into the surrounding medium. The aim of the present investigation was to provide insights into the production and release of O2- by rabbit neutrophils activated with immune complexes (IC) containing IgG antibodies of different functional affinity, opsonized and not opsonized by complement system components. For this purpose, two populations of polyclonal anti-ovalbumin (OVA) IgG antibodies with different functional affinity, 5 x 10(8) M(-1) and 2 x 10(7) M(-1), were prepared. The production of O2- was measured spectrophotometrically by a method using the superoxide dismutase-inhibited reduction of ferricytochrome C to the ferrous form. The activation of complement by different IgG-IC was determined by estimating the total residual haemolytic activity of the alternative and classical pathways in sera treated with different concentrations of anti-OVA IgG/ OVA immune complexes formed at equivalence. The results showed that: 1) antibody functional affinity influenced O2- production and the complement-fixing activity induced by the IC. In general, the higher functional affinity antibodies were more efficient in stimulating the respiratory burst of neutrophils and in activating complement by the classical and alternative pathways than the lower functional affinity antibodies at all IC concentrations tested; 2) complement components incorporated into the immune complex lattice caused an increase in the stimulatory activity of both IgG antibodies to produce O2- (approximately equal to 15% for the IC of IgG with Ka = 5 x 10(8) M(-1) and approximately equal to 7% for the IC of IgG with Ka = 2 x 10(7) M(-1)). This effect was dependent on antibody affinity and concentration; 3) there was a direct relationship between the overall level of complement activation, antibody affinity and superoxide production by neutrophils. Thus, we conclude that antibody affinity influences immune complex lattice formation, modulating its three-dimensional structure and the disposition of Fc fragments interfering with the antibody's biological properties. These results can help understand the precise role of antibody functional affinity in antigen-antibody complex diseases and define the immunochemical characteristics of pathogenic complexes.

We have established a luminol- and a lucigenin-dependent CL methods to investigate the role of the receptors for Fc portion of IgG (FcgammaR) and/or complement receptors (CR) in mediating the oxidative burst in neutrophils from systemic lupus erythematosus (SLE) patients compared with healthy controls. In the luminol-CL system, all the reactive oxygen species (ROS) are responsible for light production, whereas in the lucigenin-CL system, only the first ROS generated, converts the lucigenin into an unstable intermediate molecule, which also emits light. First, neutrophils from healthy controls and SLE patients were stimulated with different IC opsonized or not with complement from normal human serum (NHS) or SLE serum, in presence of 10(-4) M luminol. This method was able to differentiate the role of the FcgammaR, CR and FcgammaR/CR co-operation in mediating the oxidative burst, as well as show that the oxidative burst mediated by these receptors was reduced in neutrophils from SLE patients. Second, neutrophils from healthy controls and SLE patients were stimulated with different IC, opsonized or not with NHS, in presence of 10(-3) M lucigenin. In this case, the lucigenin-CL system was also able to differentiate the role of FcgammaR and FcgammaR/CR co-operation, as well as show differences among healthy controls and two different groups of SLE patients according to their clinical manifestations. In conclusion, we have established two sensitive CL systems to study the role of FcgammaR and/or CR in stimulating the oxidative burst of neutrophils, which can be applied in monitoring the involvement of these receptors in the immunopathogenesis of SLE.

Introdução: A sepse é uma condição clínica, caracterizada como disfunção inflamatória sistêmica em resposta a uma infecção, que pode levar a morte. As armadilhas extracelulares de neutrófilos (NETs) são estruturas com formato de redes e compostas por proteínas de neutrófilos sobre um arcabouço de DNA. A depuração das NETs é mediada por desoxirribonucleases (DNases), que degradam esse arcabouço. Estudos realizados por nosso grupo de pesquisa demostram um aumento da concentração de NETs no plasma de pacientes com sepse. Além disso, diversos trabalhos mostram que a degradação de NETs por DNases recombinantes melhoram o desfecho de animais com sepse. Objetivo: Analisar a modulação da atividade DNase e a expressão dessas enzimas em animais saudáveis ou com modelo de sepse experimental. Metodologia: Utilizando o modelo de ligadura e punção do ceco (CLP) analisamos a mortalidade causada pelo modelo e os níveis de citocinas no plasma dos animais, além dos níveis de NETs e a atividade DNase no baço, fígado, circulação sistêmica e no lavado peritoneal. Também no baço, fígado, e no lavado peritoneal foi analisado a expressão dos genes para as DNases 1, X e γ. Além disso, verificamos em cultivo de células aderentes do baço se as NETs isoladas e o LPS podem interferir na liberação de DNases. Adicionalmente, utilizando o modelo de sepse induzida por injeção de LPS, verificamos a influência desta toxina na atividade e expressão de DNases no lavado peritoneal. Resultados: O modelo de sepse por CLP proporcionou a mortalidade de 100% dos animais em até 48h após o procedimento, também houve aumento dos níveis das citocinas TNF-α, IL-1β e IL-6 no plasma desses animais. Os níveis de NETs foram aumentados na circulação, baço, fígado e no lavado peritoneal dos animais com sepse. A atividade DNase dos animais com sepse aumentou no lavado e na circulação após o procedimento, enquanto no baço e fígado permaneceu estável. No baço, foi observado redução da expressão de todas as DNases analisadas, em contrapartida no fígado ocorreu aumento da expressão da DNase 1 e γ, no lavado peritoneal foi observado redução da expressão da DNase γ. Além disso, ambos os estímulos (LPS e NETs) diminuíram a secreção dessas enzimas em células aderentes do baço. Dessa forma, hipotetizamos que o aumento da atividade DNase observado no lavado dos animais sépticos induzidos por CLP, não correspondem as DNases endógenas. Então foi analisado através do modelo com injeção intraperitoneal de LPS, um aumento da atividade da DNase apenas no tempo de 12h após a sepse. Além disso neste modelo, a DNase 1 apresentou aumento de expressão em 12 horas e a DNase γ teve um aumento de expressão em 6 horas seguida por diminuição nos tempos posteriores. Conclusões: Nossos resultados mostram que em animais que passaram pela indução de sepse por CLP há um aumento da atividade Dnase no local da infecção, esse aumento parece ser dependente da presença de bactérias. Além disso, demonstramos que durante a sepse há modulação da expressão de DNases, que parece ser mediada pelo LPS. Introduction: Sepsis is characterized as life-threatening inflammatory dysfunction in response to an infection, which can lead to death. Extracellular neutrophil traps (NETs) are net-like structures composed of neutrophil proteins on a DNA scaffold. The clearance of NETs is mediated by deoxyribonucleases (DNases), which degrade this backbone. Studies carried out by our research group show an increase in the concentration of NETs in the plasma of patients with sepsis. In addition, several studies show that the degradation of NETs by recombinant DNases improves the outcome of animals with sepsis. Objective: Analyze the modulation of DNase activity and the expression of these enzymes in healthy or in an experimental sepsis model animals. Methodology: Using the cecum ligation and puncture (CLP) model, we analyzed the mortality caused by sepsis and the levels of cytokines in the plasma of the animals. Also, we evaluated NETs levels and DNase activity in spleen, liver, systemic circulation and peritoneal cavity. In addition, we analyzed the expression of DNases 1, X and γ genes in spleen, liver, and peritoneal lavage. Furthermore, we verified whether NETs and LPS can interfere with the release of DNases by adherent spleen cells. Using the LPS-induced sepsis model, we verified whether this substance can influence the activity and expression of DNases in peritoneal cavity. Results: The CLP model of sepsis provided the mortality of 100% of the animals within 48 hours after the procedure and increased the levels of cytokines TNF-α, IL-1β and IL-6 in the plasma of CLP animals. NETs levels were increased in the circulation, spleen, liver and peritoneal lavage of animals with sepsis. The DNase activity of the animals with sepsis increased in the lavage and in the circulation after the procedure, while in the spleen and liver did not show any difference. In the spleen, a reduction in the expression of all DNases analyzed was observed, in contrast, in the liver, there was an increase in the expression of DNase 1 and γ, in the peritoneal lavage, a reduction in the expression of DNase γ was observed. We observed that both stimuli (LPS and NETs) decrease the secretion of these enzymes by these cells. These results led us to the hypothesis that the increase in DNase activity observed in the washing of septic animals induced by CLP does not correspond to endogenous DNases. Thus, it was analyzed that in the endotoxin model, through the intraperitoneal injection of LPS, there was an increase in DNase activity only at the time of 12 h after sepsis. It was also possible to observe a different pattern of DNase expression in this model, DNase 1 showed an increase in expression at 12 hours and DNase γ had an increase in expression at 6 hours followed by a decrease. Conclusions: Our results show that in animals that underwent sepsis induction by CLP there is an increase in Dnase activity at the site of infection, this increase seems to be dependent on the presence of bacteria. Furthermore, we demonstrated that during sepsis there is modulation of DNase expression, which seems to be mediated by LPS.

O melanoma é um câncer de pele caracterizado pela alta mortalidade devido à resistência à quimioterapia e à capacidade metastática. Aproximadamente metade dos casos de melanoma maligno apresenta mutações que ativam o gene BRAF, na maioria das vezes envolvendo a substituição V600E. Dessa forma, os inibidores de BRAF, como o Vemurafenibe, têm sido utilizados no tratamento deste tipo de câncer. Apesar da resposta inicial às opções terapêuticas ser satisfatória, a maioria dos pacientes apresenta remissão da doença em um curto período de tempo. Avaliar como mediadores lipídicos interferem nos mecanismos de resistência é uma estratégia para novos tratamentos mais efetivos ao melanoma resistente. Dessa forma, o nosso objetivo foi avaliar o papel dos mediadores lipídicos na resistência das linhagens de células de melanoma humano ao Vemurafenibe. Neste trabalho, demonstramos que as linhagens de melanoma humano (A375, SK-MEL-29, WM35 e WM278) e os melanócitos são capazes de produzir diferentes mediadores lipídicos quando estimulados in vitro e que, dentre elas, as linhagens metastáticas (A375 e SK-MEL-29), tanto as parentais (P) quanto as resistentes (R), sintetizam concentrações maiores desses compostos. Além disso, observamos através do ensaio de Azul de tripan e em modelo 3D utilizando esferoides que o tratamento das células metastáticas (A375P e R e SK-MEL-29P e R) com PGD2 diminuiu a proliferação celular e interferiu na produção das citocinas IL-6, IL-8 e IL-10 de modo independente dos receptores DP1 e DP2. Ainda, observamos que a PGJ2, metabólito da PGD2, também reduziu in vitro a proliferação das células de melanoma A375P e SK-MEL-29 P e R, por uma via independente do receptor PPAR. Dessa forma, investigamos possíveis vias metabólicas que poderiam estar perturbadas nas células A375P e R após o tratamento com PGD2. Nossas análises mostraram que vias como metabolismo de xenobióticos, metabolismo de cisteína e metionina e a transferência via carnitina foram especificamente perturbadas nesta comparação e, portanto, sugerem que as diferenças fenotípicas após tratamento com PGD2 sejam resultado de alterações nestas vias metabólicas. Portanto, nossos resultados contribuem para o desenvolvimento de novas terapêuticas que possibilitem a prevenção ou retardamento das metástases e, consequentemente, melhor prognóstico da doença. Melanoma is a skin cancer characterized by high mortality due to resistance to chemotherapy and metastatic capacity. Approximately half of the cases of malignant melanoma have mutations that activate the BRAF gene, mainly involving the V600E substitution. Thus, BRAF inhibitors, such as Vemurafenib, have been used to treat this type of cancer. Although the initial response rate is effective, disease progression and tumor resistance rapidly occurs in the majority of patients. Assessing how lipid mediators interfere with resistance mechanisms is a strategy for new, more effective treatments for resistant melanoma. Thus, our objective was to evaluate the role of lipid mediators in the resistance of human melanoma cell lines to Vemurafenib. In this work we demonstrate that human melanoma cell lines (A375, SK-MEL-29, WM35 and WM278) and melanocytes are able to produce different lipid mediators when stimulated in vitro and that, among them, metastatic cells (A375 and SK- MEL-29), both parental (P) and resistant (R), synthesize higher concentrations of these compounds. In addition, we observed through the trypan blue assay and in a 3D model using spheroids that the treatment of metastatic cells (A375P and R and SK-MEL-29P and R) with PGD2 decreased cell proliferation and interfered with the cytokines production (IL- 6, IL-8 and IL-10) independently of DP1 and DP2 receptors. Furthermore, we observed that PGJ2, a metabolite of PGD2, also reduced the proliferation of A375P and SK-MEL-29P and R melanoma cells in vitro, via a PPAR receptor-independent pathway. Thus, we investigated possible metabolic pathways that could be disturbed in A375P and R cells after treatment with PGD2. Our analyzes showed that pathways such as xenobiotic metabolism, cysteine and methionine metabolism and transfer via carnitine were specifically disturbed in this comparison and therefore suggest that phenotypic differences after treatment with PGD2 are the result of changes in these metabolic pathways. Therefore, our results contribute to the development of new therapies that enable the prevention or delay of metastasis and, consequently, a better prognosis of the disease.

Estima-se que aproximadamente 38 milhões de pessoas ao redor do mundo são portadoras do vírus da imunodeficiência adquirida (HIV, do inglês human immunodeficiency virus) e que em torno de 2 milhões de novas infecções ocorram por ano. No Brasil, desde o início da epidemia de AIDS (síndrome da imunodeficiência adquirida, do inglês acquired immunodeficiency syndrome) até junho de 2018, foram registrados 926.742 casos. Desses casos, 327.655 óbitos foram identificados tendo como causa básica a síndrome. Nessa perspectiva, ferramentas diagnósticas para detecção rápida e eficaz da infecção são essenciais para a contenção da doença. Descreve-se nessa dissertação a validação de um kit para diagnóstico rápido que utiliza a metodologia de imunocromatografia para detecção de anticorpos anti-HIV 1/2, chamado \"Imuno-Rápido HIV\", da empresa WAMA Diagnóstica. O produto teve seu desempenho comparado ao de outro kit disponível no mercado, que utiliza a mesma metodologia (Comercial A) e ao da técnica de quimioluminescência, tomada como padrão para esse ensaio. Realizaram-se os testes de sensibilidade e especificidade clínicas, utilizando 734 amostras de soro e sangue total. Foram realizados diversos testes para avaliação do kit quanto sensibilidade, especificidade, repetibilidade, reprodutibilidade, bem como estudos para estimar e/ou determinar seu prazo de validade. O kit avaliado apresentou sensibilidade clínica de 100% e especificidade clínica de 99,77%. Em relação à repetibilidade e reprodutibilidade, em 100% das vezes os resultados intra e inter-ensaio foram coincidentes e o mesmo continuou apresentando bons resultados quando submetido aos testes de estabilidade acelerada e real, apontando que o prazo de validade do produto seja de pelo menos 18 meses. O produto não sofreu interferências frente a amostras hemolisadas, lipêmicas, ictéricas e congeladas e descongeladas várias vezes. Em relação à especificidade analítica, o teste não sofreu interferência significativa em amostras reagentes para Fator Reumatoide (FR), Hepatite C (HCV), Hepatite B (HBsAg), e apresentou pequena interferência (2%) para pacientes gestantes (HCG positivo). O kit Imuno-Rápido HIV mostrou-se capaz de detectar anticorpos anti-HIV, apresentando sensibilidade e especificidade dentro dos padrões desejáveis, e eficácia comparável a outros kits do mercado, podendo ser uma ferramenta importante para detecção da infecção pelo HIV na população. It is estimated that almost 38 million people around the world are living with HIV and about 2 million new infections occur every year. In Brazil, since the beginning of the AIDS epidemic up to June, 2018, 926,742 cases were reported, of which 327,655 led to death by the syndrome. With this scenario, diagnostic tools for quick and effective detection of the infection are indispensable for the disease contention. This work describes the validation process of a kit for rapid diagnostic of HIV infection, which relies on immunochromatography method for detection of anti-HIV 1/2 antibodies, called \"Imuno-Rápido HIV\", by WAMA Diagnóstica. This product\'s performance was compared to another commercially available kit, that uses the same method and technology (Commercial A), and also to the technique of chemiluminescence, taken as the standard for this assay. Clinical sensitivity and specificity tests were performed using 734 serum and whole blood samples. Several tests were performed to evaluate the product regarding sensitivity, specificity, repeatability, reproducibility and estimation/determination of shelf life. The kit presented 100% clinical sensitivity and 99,77% clinical specificity. Regarding repeatability and reproducibility, 100% of the times the intra and inter-assay results were in accordance to the expected. Test performance was good even when submitted to the temperature stress in the accelerated stability assay. This result was confirmed by the real time stability test, that showed that the kit has a shelf-life of at least 18 months. The product didn\'t show interference from hemolyzed, lipemic, icteric or frozen/thawed samples. Regarding analytical specificity, the kit didn\'t cross react with rheumatoid factor (RF), Hepatitis C (HCV) and Hepatitis B (HBsAg) reactive samples. It presented slight interference in pregnant women samples (around 2%). Thus, Imuno-Rápido HIV has shown to be able to successfully detect anti-HIV antibodies with high sensitivity and specificity, within desirable standards, an efficacy comparable to other products of the marker, meaning it can be an important tool for early HIV detection in population in general.

Neutrófilos são a primeira linha de defesa do sistema imunológico, eles produzem substâncias microbicidas, tais como espécies reativas de oxigênio (ERO), são capazes de eliminar patógenos e possuem papel importante em processos inflamatórios fisiológicos e patológicos. No entanto, os efeitos benéficos e nocivos mediados por esta célula dependem, em grande parte, do equilíbrio redox, que se estabelece entre a produção de ERO e a ação de antioxidantes. A quebra deste equilíbrio leva ao estresse oxidativo, capaz de causar danos pelas ERO sobre as estruturas biológicas. Sendo assim, a regulação das funções dos neutrófilos é um importante alvo terapêutico. O objetivo deste trabalho foi avaliar a ação de produtos naturais - extrato bruto, frações e subfrações - oriundas da Antártica na regulação do metabolismo oxidativo de neutrófilos humanos. Para este propósito, o extrato bruto da alga Palmaria decipiens, nove (9) frações do fungo endofítico Aspergillus unguis e nove (9) subfrações deste foram estudadas. As amostras foram avaliadas quanto à atividade scavenger, utilizando-se o 2,2-difenil-?-picrilhidrazil; à citotoxidade aos neutrófilos, por análise da viabilidade celular com o ensaio de exclusão do Azul de Trypan; e ao efeito sobre a produção de ERO pelos neutrófilos, medida por quimiluminescência dependente de luminol, utilizando-se forbol-12-miristato-13-acetato como estímulo para os neutrófilos. Os resultados mostraram que: 1) nenhuma das amostras apresentou atividade scavenger; 2) a viabilidade celular manteve-se igual ou maior que 90% quando neutrófilos foram expostos às frações FR5, FR6*, FR8, e às subfrações contendo 100% Acetato de Etila, 10% Acetato de Etila:Hexano, 20% Acetato de Etila:Hexano e 40% Acetato de Etila:Hexano; 3) dentre as frações que mostraram viabilidade celular maior que 90%, a inibição da produção de ERO pelos neutrófilos foi observada com a FR5 (51%), a FR6* (20%), a subfração 100% Hexano (73%), a subfração 20% Acetato de Etila/Hexano (42%) e a subfração 40% Acetato de Etila/Hexano (38%). Os resultados mostram que algumas das frações e subfrações do fungo endofítico Aspergillus unguis apresentaram inibição da produção de ERO pelos neutrófilos humanos entre (20 a 73%). Esta inibição não é por atividade scavenger de radiciais de oxigênio, sugerindo que este efeito regulador sobre o neutrófilo possa resultar da atividade dos componentes nestas frações sobre outras vias metabólicas desta célula. A partir destes resultados, faz-se necessário identificar a composição destas frações e seus efeitos sobre vias metabólicas e sobre outras funções efetoras dos neutrófilos. A contribuição deste estudo é a procura por moléculas bioativas, capazes de regular parcialmente as respostas do neutrófilo, para restabelecer o equilíbrio funcional desta célula em estados patológicos, diminuindo seus efeitos nocivos sem prejuízo do seu papel crucial para a homeostase. Neutrophils are the first line of defense of the immune system, they produce microbicidal substances, such as reactive oxygen species (ROS), able to eliminate pathogens and play important roles in physiological and pathological inflammatory processes. However, the beneficial and harmful effects mediated by this cell depend on the redox balance, which is established between the production of ROS and the action of antioxidants. The imbalance leads to oxidative stress capable of causing damage by ROS on biological structures. Thus, the regulation of neutrophil functions is an important therapeutic target. The aim of this work was to evaluate the action of natural products - crude extract, fractions and subfractions - originating from Antarctica environment in the regulation of the oxidative metabolism of human neutrophils. For this purpose, the crude extract of the Palmaria decipiens algae, nine (9) fractions of the endophytic fungus Aspergillus unguis and nine (9) subfractions from this fungus were studied. The samples were evaluated for scavenger activity using 2,2-diphenyl-?-picrylhydrazyl; cytotoxicity to neutrophils, by cellular viability analysis with the Trypan Blue exclusion assay; and to the effect on neutrophil production of ROS, as measured by luminol-dependent chemiluminescence, using phorbol 12-myristate 13-acetate as a stimulus for neutrophils. The results showed that: 1) none of the samples had scavenger activity; 2) the cell viability remained equal to or greater than 90% when neutrophils were exposed to fractions FR5, FR6*, FR8, and subfractions containing 100% Ethyl Acetate, 10% Ethyl Acetate:Hexane, 20% Ethyl Acetate:Hexane and 40% Ethyl Acetate:Hexane; 3) among the fractions that showed cellular viability greater than 90%, the inhibition of ROS production by neutrophils was observed with FR5 (51%), FR6* (20%), subfraction 100% Hexane (73%), the subfraction 20% Ethyl acetate / Hexane (42%) and subfraction 40% Ethyl acetate / Hexane (38%). The results show that some of the fractions and subfractions of the endophytic fungus Aspergillus unguis showed inhibition of ROS production by human neutrophils between (20 to 73%). This inhibition is not by scavenger activity of oxygen radicals, suggesting that this regulatory effect on the neutrophil may result from the activity of the components in these fractions on other metabolic pathways of this cell. From these results, it is necessary to identify the composition of these fractions and their effects on metabolic pathways and on other effector functions of neutrophils. The contribution of this study is the search for bioactive molecules, able to partially regulate neutrophil responses, to restore the functional balance of this cell in pathological states, reducing its harmful effects without prejudice to its crucial role for homeostasis.