ABSTRACT
Corpúsculos lipídicos são organelas citoplasmáticas envolvidas na produção de eicosanoides em leucócitos. Eicosanoides como as prostaglandinas têm sido envolvidos no controle da resposta inflamatória e imunológica. A saliva de Lutzomyia longipalpis participa do estabelecimento e desenvolvimento da doença pela modulação das respostas hemostática, imunológica e inflamatória do hospedeiro favorecendo a infecção. Entretanto, o papel dos eicosanoides nos momentos iniciais da infecção por Leishmania ainda não foi esclarecido, assim como a participação da saliva neste contexto. Aqui, nós investigamos o papel dos eicosanoides induzidos pela saliva de L. longipalpis e produzidos pela Leishmania infantum chagasi na infecção. O sonicado de glândula salivar (SGS) de L. longipalis induziu um aumento no número de CLs em macrófagos de maneira dose e tempo dependente, o qual esteve correlacionado com o aumento de PGE2 nos sobrenadante de cultura. As enzimas COX-2 e PGE- intase foram co-localizadas nos CLs induzidos pela saliva e a produção de PGE2 foi reduzida pelo tratamento com NS-398, um inibidor de COX-2. Nós verificamos que o SGS rapidamente estimulou a fosforilação de ERK-1/2 e PKC-α e a inibição farmacológica dessas vias inibiu a produção de PGE2 pelos macrófagos estimulados com SGS. Em seguida, nós avaliamos o efeito da saliva de L. longipalpis sobre a produção de eicosanoides durante a infecção por L. i. chagasi no modelo peritoneal murino. Nós observamos que a saliva aumentou a viabilidade intracelular de L. i. chagasi tanto em neutrófilos como em neutrófilos recrutados para a cavidade peritoneal. As células recrutadas para cavidade peritoneal apresentaram maiores níveis da relação PGE2/LTB4 e o pré-tratamento com NS-398 reverteu o efeito da saliva sobre a viabilidade intracelular dos parasitas. Parasitas como Leishmania são capazes de produzir PGs utilizando uma maquinaria enzimática própria. Neste estudo nós descrevemos a dinâmica de formação e a distribuição celular dos CLs em L. i. chagasi bem como a participação desta organela na produção de PGs. A quantidade de CLs aumentou durante a metaciclogênese assim como a expressão de PGF2α sintase (PGFS), sendo esta enzima co-localizada nos CLs. A adição de ácido araquidônico AA à cultura de L. i. chagasi aumentou a quantidade de CLs por parasita, bem como a secreção de PGF2α. A infecção com as diferentes formas de L. i. chagasi não foi capaz de estimular a formação de CLs na célula hospedeira. Por outro lado, os parasitas intracelulares apresentaram maiores quantidades de CLs. A infecção estimulou uma rápida expressão de COX-2, mas não foi detectado aumento na produção de PGF2α nos sobrenadantes. Por fim, nós verificamos a presença do receptor de PGF2α (FP) nos vacúolos parasitóforos de macrófagos infectados com L. i. chagasi. O prétratamento das células com um antagonista do receptor FP inibiu os índices de infecção de forma dose-dependente. Em conjunto, nossos dados apontam que os eicosanoides desempenham um papel crucial para evasão da resposta imune durante os momentos iniciais da infecção por L. i. chagasi com diferentes contribuições do parasita, do vetor e da célula hospedeira neste contexto.
Diffuse Cutaneous Leishmaniasis (LCD) is a rare clinical manifestation of Leishmaniasis, characterized by a number of macrophages heavily parasitized and low inflammatory reaction. In Brazil, Leishmania (Leishmania) amazonensis is the main specie involved in LCD cases. It has been described that the exposure and recognition of phosphatidylserine (PS) on the surface of apoptotic cells phagocytosed by macrophages is a macrophage deactivation mechanism dependent on TGF-pi and PGE2 (Fadok et al. 1998). Morover, it was demonstrated by Barcinski and colleagues that L. amazonensis amastigotes expose PS on its surface, in a mechanism called Apoptotic Mimicry." In this context, our goal was to investigate the exposure of PS on the surface of L. amazonensis isolates obtained from LCD patients and its role during the infection of macrophages. Initially, peritoneal macrophages from FI mice (BALB/c x C57BL/6) stimulated with thioglycolate were infected with different L. amazonensis strains isolated from patients with Localized Cutaneous Leishmaniasis (LCL) or LCD. The exposure of PS on the surface of amastigotes was determined by flow cytometry using staining to annexin V and propidium iodide. Isolates from LCD patients showed higher PS exposure than the isolates from LCL patients 24 hours after infection. Then, we evaluated whether the differences of PS exposure in amastigotes would correlate with the infectivity of different isolates. Percentage of infected macrophages and infection index were higher in cultures using amastigotes from LCD patients compared to the ones infected with amastigotes from LCL cases. Furthermore, cultures infected with LCD isolates showed no difference to the LCL isolates regarding TGF>pl and nitric oxide production, suggesting that other immuneregulatory mechanisms are involved in this process...
Subject(s)
Humans , Blood Cells/immunology , Eicosanoids/antagonists & inhibitors , Leishmania/pathogenicity , Psychodidae/parasitologyABSTRACT
O desenvolvimento da rinite alérgica (RA) e da asma requer uma interação entre ambiente, sistema imunológico e susceptibilidade genética. Enquanto a rinite induzida por pólen é a mais característica doença alérgica mediada pela imunoglobulina E, na RA perene os desencadeantes da alergia são mais contínuos e levam à inflamação constante. Várias células e mediadores coordenam e mantêm essa inflamação. Embora a histamina ainda seja um dos principais mediadores da reação alérgica, muitos outros mediadores produzidos por diferentes tipos celulares estão envolvidos. Assim, a intrincada interação entre esses mediadores, citocinas, quimiocinas, neuropeptídeos, moléculas de adesão e várias células na forma de uma rede complexa leva ao desenvolvimento de sintomas específicos e à hiper-reatividade não específica presente na RA. A asma é caracterizada por graus variáveis de inflamação crônica e alterações estruturais nas vias aéreas que incluem denudação epitelial, metaplasia das células caliciformes, espessamento subepitelial, aumento da massa do músculo liso nas vias aéreas, aumento das glândulas brônquicas, angiogênese, e alterações nos componentes da matriz extracelular envolvendo as pequenas e grandes vias aéreas. Acredita-se que a inflamação crônica inicie e perpetue ciclos de dano e reparo tecidual na asma, embora o remodelamento também possa ocorrer em paralelo com a inflamação. Ao mesmo tempo em que RA e asma apresentam várias semelhanças em termos de perfil e resposta das células inflamatórias e dos mediadores, o remodelamento como observado na asma não é característico da RA. Na asma, as relações entre inflamação e remodelamento das vias aéreas e função pulmonar estão sendo melhor compreendidas. Uma variedade de células inflamatórias e células estruturais atuam na coordenação da inflamação e das mudanças estruturais na asma. O aumento da responsividade das vias aéreas é um marcador substituto de inflamação e pode refletir o desenvolvimento de mudanças estruturais nas vias aéreas. Tal aumento persistente da responsividade brônquica aponta para a ocorrência de remodelamento parcialmente resistente à terapia.
The development of AR and asthma requires an interaction between the environment, imune system and genetic susceptibility. While pollen-induced rhinitis is the most characteristic IgE mediated allergic disease, in perennial allergic rhinitis the allergic triggers are more continuous, and lead to on going inflammation. Several cells and mediators orchestrate and maintain this inflammation. Although histamine is still one of the major mediators of the allergic reaction, many other mediators produced by different cell types are involved. Thus, the intricate interaction amongst these mediators, cytokines, chemokines, neuropeptides, adhesion molecules and various cells in the form of a complex network leads to the development of specific symptoms and the non specific hyperreactivity of allergic rhinitis. Asthma is characterized by variable degrees of chronic inflammation and structural alterations in the airways which include epithelial denudation, goblet cell metaplasia, subepithelial thickening, increased airway smooth muscle mass, bronchial gland enlargement, angiogenesis, and alterations in extracellular matrix components, involving large and small airways. Chronic inflammation is thought to initiate and perpetuate cycles of tissue injury and repair in asthma, although remodeling may also occur in parallel with inflammation. While AR and asthma share several similarities in the inflammatory cell and mediator profiles and responses, remodeling as seen in asthma is not characteristic of AR. In asthma, the relationships of airway inflammation, remodeling and lung function are becoming better understood. A variety of inflammatory cells and structural cells play a role in orchestrating the inflammation and structural changes in asthma. Increased airway responsiveness is a surrogate marker of inflammation and may reflect the development of structural changes in the airways. Such persistent increased bronchial responsiveness indicates remodeling which is partly resistant to therapy.
Subject(s)
Humans , Child, Preschool , Child , Airway Remodeling , Asthma , Cytokines , Blood Cells/immunology , Histamine , Inflammation Mediators , Rhinitis, Allergic , Diagnostic Techniques and Procedures , Inflammation , Methods , PatientsABSTRACT
INTRODUCTION: The innate immune response is the first mechanism of protection against Trypanosoma cruzi, and the interaction of inflammatory cells with parasite molecules may activate this response and modulate the adaptive immune system. This study aimed to analyze the levels of cytokines and chemokines synthesized by the whole blood cells (WBC) and peripheral blood mononuclear cells (PBMC) of individuals seronegative for Chagas disease after interaction with live T. cruzi trypomastigotes. METHODS: IL-12, IL-10, TNF-α, TGF-β, CCL-5, CCL-2, CCL-3, and CXCL-9 were measured by ELISA. Nitrite was determined by the Griess method. RESULTS: IL-10 was produced at high levels by WBC compared with PBMC, even after incubation with live trypomastigotes. Production of TNF-α by both PBMC and WBC was significantly higher after stimulation with trypomastigotes. Only PBMC produced significantly higher levels of IL-12 after parasite stimulation. Stimulation of cultures with trypomastigotes induced an increase of CXCL-9 levels produced by WBC. Nitrite levels produced by PBMC increased after the addition of parasites to the culture. CONCLUSIONS: Surface molecules of T. cruzi may induce the production of cytokines and chemokines by cells of the innate immune system through the activation of specific receptors not evaluated in this experiment. The ability to induce IL-12 and TNF-α contributes to shift the adaptive response towards a Th1 profile.
INTRODUÇÃO: A resposta imune inata é o primeiro mecanismo de proteção contra o Trypanosoma cruzi e a interação de células inflamatórias com moléculas do parasita pode ativar esta resposta e modular a resposta adaptativa. O objetivo deste trabalho foi analisar os níveis de citocinas e quimiocinas sintetizados por células do sangue total (WBC) e células mononucleares do sangue periférico (PBMC) de voluntários soronegativos para doença de Chagas depois da interação com Trypanosoma cruzi. MÉTODOS: IL-12, IL-10, TNF-α, TGF-β, CCL5, CCL2, CCL3, CXC-9 foram avaliados por ELISA. Níveis de nitrito foram determinados pelo método de Griess. RESULTADOS: Foram produzidos altos níveis de IL-10 por WBC quando comparado aos sintetizados por PBMC, inclusive após incubação com tripomastigotas. A produção de TNF-α foi significativamente maior nas culturas de PBMC e WBC após estímulo com o parasita. O aumento significativo dos níveis de IL-12 foi observado apenas em PBMC depois do estímulo com tripomastigotas. A adição de tripomastigotas nas culturas induziu aumento dos níveis de CXCL9 produzidos por WBC. Os níveis de nitrito produzidos pelos PBMCs de todos os voluntários após a adição de parasito nas culturas aumentaram. CONCLUSÕES: Moléculas de superfície do parasito podem induzir a produção de citocinas e quimiocinas pelas células da resposta imune inata através da ativação dos receptores específicos não avaliados neste experimento. A habilidade de induzir IL-12 e TNF-α contribui para direcionar uma resposta imune adaptativa de perfil Th1.
Subject(s)
Adolescent , Adult , Animals , Humans , Young Adult , Blood Cells/parasitology , Chagas Disease/immunology , Chemokines/biosynthesis , Cytokines/biosynthesis , Immunity, Innate/immunology , Trypanosoma cruzi/immunology , Blood Cells/immunology , Chlorocebus aethiops , Enzyme-Linked Immunospot Assay , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/parasitology , Nitrites/analysis , Vero CellsABSTRACT
The mainstay of management of severe beta-thalassemia remains lifelong blood transfusion. The development of one or more alloantibody against specific red cell minor antigens is a common complication of chronic transfusion therapy. Delayed hemolytic transfusion reactions are due to alloantibodies cause increased blood requirement in transfusiondependent beta-thalassemia patients. This study was performed to detect the frequency and predominant pattern of alloimmunization in the target population. This is a cross-sectional study carried out on 133 transfusion- dependent beta-thalassemia patients referring to Shafa hospital-Ahvaz. Antibody screening and identification technique employed was tube method. All panel test phases were done at immunohematology laboratory of Iranian Blood Transfusion Organization. Among the selected patients, 66 were males [49.1%] and 67 were females [50.9%], with a mean age of 17.63 years [SD +/- 7.6]. The antibody screening panel was positive in 42 patients [31.57%], of whom 25 patients [59.52%] had alloantibody and 17 patients [40.50%] additionally had autoantibody. The predominant patterns of alloimmunization were anti-Rh [55%] and anti-Kell [33%]. Frequency of alloimmunization were significant with increasing duration of transfusion [P=0.01], history of splenectomy [P=0.03] and beta-thalassemia intermedia [P=0.02]. Alloimmunization was a common complication in our transfusion-dependent beta-thalassemia patients. It's recommended that before embarking on transfusion therapy, patients should have extended red cell antigen typing that includes at least Rh and Kell blood grouping, in order to help reduce the likelihood of development of immunological responses later
Subject(s)
Humans , Male , Female , Adolescent , Isoantibodies , Blood Group Antigens , Blood Cells/immunology , Prevalence , Cross-Sectional Studies , Blood Transfusion/adverse effects , beta-ThalassemiaABSTRACT
This work evaluated the acute inflammatory response induced by injections of 0.5 mL saline solution (control), 500 µg carrageenin and 0.5 mL thioglycollate 3 percent in the swim bladder of juvenile tambacu hybrid. Fish were distributed in three treatments, three replications and acclimated for a period of 10 days before assay. The cell characterization from the inflammatory exudate was performed in Giemsa and PAS stained smears. Carrageenin, injected in fish, showed an increase on the total number of cells in the inflammatory exudate when compared to saline and thioglycollate injected. Whereas, for carrageenin-injected fish, the percentage of thrombocyte was higher than thioglycollate. On the other hand, granulocyte percentage in thioglycollate-injected fish was higher than the ones injected using carrageenin. Carrageenin provoked the highest migration of macrophage to the inflammatory site. The PAS method confirmed the presence of three types of granulocytes: eosinophilic granular cell (EGC) type 1 with the characteristics of a special granulocytic cell commonly found in the circulating blood; EGC type 2 shorter than the last one and neutrophil. This study contributes to a better understanding of the inflammatory response and infectious processes in native fish.
Este estudo avaliou a resposta inflamatória aguda induzida por injeções de 0,5 mL de solução salina (controle), 500 µg de carragenina e 0,5 mL de tioglicolato a 3 por cento na bexiga natatória de juvenis do híbrido tambacu. Os peixes foram distribuídos em três tratamentos, três repetições e aclimatados durante 10 dias antes do ensaio. A caracterização das células do exsudato inflamatório foi feita após coloração com Giemsa e PAS. Peixes injetados com carragenina apresentaram maior número de células no exsudato inflamatório do que com salina e tioglicolato. A porcentagem de trombócitos no exsudato foi maior nos injetados com carragenina quando comparada com a dos injetados com tioglicolato. Por outro lado, o percentual de granulócitos foi maior em animais injetados com tioglicolato do que em animais injetados com carragenina. A carragenina provocou maior migração de macrófagos para o foco inflamatório. O método de PAS confirmou a presença de três tipos de granulócitos: célula granular eosinofílica (CGE) tipo 1 com as características da célula granulocítica especial encontrada no sangue, CGE tipo 2, menor do que esta última, e de neutrófilos. Este estudo contribui para o melhor entendimento da resposta inflamatória e dos processos infecciosos em peixes nativos.
Subject(s)
Animals , Female , Male , Blood Cells/immunology , Cell Movement/immunology , Exudates and Transudates/immunology , Fish Diseases/immunology , Fishes/immunology , Inflammation/veterinary , Acute Disease , Carrageenan , Chimera , Fish Diseases/chemically induced , Fish Diseases/pathology , Inflammation/chemically induced , Inflammation/immunology , Inflammation/pathology , ThioglycolatesABSTRACT
Because low tumor necrosis factor-alpha (TNF-alpha) production has been reported in malnourished children, in contrast with high production of TNF-alpha in experimental protein-energy malnutrition, we reevaluated the production of TNF-alpha in whole blood cultures from children with primary malnutrition free from infection, and in healthy sex- and age-matched controls. Mononuclear cells in blood diluted 1:5 in endotoxin-free medium released TNF-alpha for 24 h. Spontaneously released TNF-alpha levels (mean ± SEM), as measured by enzyme immunoassay in the supernatants of unstimulated 24-h cultures, were 10,941 ± 2,591 pg/ml in children with malnutrition (N = 11) and 533 ± 267 pg/ml in controls (N = 18) (P < 0.0001). TNF-alpha production was increased by stimulation with lipopolysaccharide (LPS), with maximal production of 67,341 ± 16,580 pg/ml TNF-alpha in malnourished children and 25,198 ± 2,493 pg/ml in controls (P = 0.002). In control subjects, LPS dose-dependently induced TNF-alpha production, with maximal responses obtained at 2000 ng/ml. In contrast, malnourished patients produced significantly more TNF-alpha with 0.02-200 ng/ml LPS, responded maximally at a 10-fold lower LPS concentration (200 ng/ml), and presented high-dose inhibition at 2000 ng/ml. TNF-alpha production a) was significantly influenced by LPS concentration in control subjects, but not in malnourished children, who responded strongly to very low LPS concentrations, and b) presented a significant, negative correlation (r = -0.703, P = 0.023) between spontaneous release and the LPS concentration that elicited maximal responses in malnourished patients. These findings indicate that malnourished children are not deficient in TNF-alpha production, and suggest that their cells are primed for increased TNF-alpha production.
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Tumor Necrosis Factor-alpha , Blood Cells/immunology , Child Nutrition Disorders/immunology , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/immunology , Case-Control Studies , Cells, CulturedABSTRACT
The pathogenesis of aplastic anemia in Thailand was studied by using in vitro progenitor cells culture. In 37 patients who had active disease, the numbers of colonies derived from erythroid and granulocyte-macrophage progenitor cells (BFU-E and CFU-GM) were markedly decreased both in the blood and bone marrow as compared to normal controls. Co-culture of patients' cells with normal blood cells was performed in order to verify an immunologically mediated mechanism. In 8 of 26 patients, there were very low numbers of colonies both BFU-E and CFU-GM in the blood and bone marrow with significant suppression of colony formation in co-culture. Suppressor cells may have caused the aplasia in these patients. The rest had low colony formation and no suppression in co-culture. These patients may have absent or defective stem cells. None had normal colony formation. Therefore, aplastic anemia in Thailand may result mostly from defects involving the stem cells. Only some patients had cell mediated suppression of hematopoiesis as detected by co-culture.