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1.
Front Immunol ; 12: 661241, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122419

RESUMO

As a relatively successful pathogen, several parasites can establish long-term infection in host. This "harmonious symbiosis" status relies on the "precise" manipulation of host immunity and metabolism, however, the underlying mechanism is still largely elusive. Immunometabolism is an emerging crossed subject in recent years. It mainly discusses the regulatory mechanism of metabolic changes on reprogramming the key transcriptional and post-transcriptional events related to immune cell activation and effect, which provides a novel insight for understanding how parasites regulate the infection and immunity in hosts. The present study reviewed the current research progress on metabolic reprogramming mechanism exploited by parasites to modulate the function in various immune cells, highlighting the future exploitation of key metabolites or metabolic events to clarify the underlying mechanism of anti-parasite immunity and design novel intervention strategies against parasitic infection.


Assuntos
Células Dendríticas/imunologia , Linfócitos/imunologia , Macrófagos/imunologia , Doenças Parasitárias/imunologia , Plasmodium/imunologia , Schistosoma/imunologia , Trypanosoma/imunologia , Animais , Células Dendríticas/metabolismo , Células Dendríticas/parasitologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Linfócitos/metabolismo , Linfócitos/parasitologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Doenças Parasitárias/metabolismo , Doenças Parasitárias/parasitologia , Plasmodium/fisiologia , Schistosoma/fisiologia , Trypanosoma/fisiologia
2.
Immunity ; 52(3): 528-541.e7, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32160525

RESUMO

Helminths, allergens, and certain protists induce type 2 immune responses, but the underlying mechanisms of immune activation remain poorly understood. In the small intestine, chemosensing by epithelial tuft cells results in the activation of group 2 innate lymphoid cells (ILC2s), which subsequently drive increased tuft cell frequency. This feedforward circuit is essential for intestinal remodeling and helminth clearance. ILC2 activation requires tuft-cell-derived interleukin-25 (IL-25), but whether additional signals regulate the circuit is unclear. Here, we show that tuft cells secrete cysteinyl leukotrienes (cysLTs) to rapidly activate type 2 immunity following chemosensing of helminth infection. CysLTs cooperate with IL-25 to activate ILC2s, and tuft-cell-specific ablation of leukotriene synthesis attenuates type 2 immunity and delays helminth clearance. Conversely, cysLTs are dispensable for the tuft cell response induced by intestinal protists. Our findings identify an additional tuft cell effector function and suggest context-specific regulation of tuft-ILC2 circuits within the small intestine.


Assuntos
Cisteína/imunologia , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Leucotrienos/imunologia , Nippostrongylus/imunologia , Infecções por Strongylida/imunologia , Animais , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/imunologia , Araquidonato 5-Lipoxigenase/metabolismo , Cisteína/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Imunidade Inata/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-17/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/parasitologia , Intestino Delgado/citologia , Intestino Delgado/metabolismo , Leucotrienos/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/parasitologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Nippostrongylus/fisiologia , Infecções por Strongylida/parasitologia
3.
Parasitol Int ; 73: 101948, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31247308

RESUMO

This study aimed to evaluate nucleoside triphosphate diphosphohydrolase (NTPDase) and adenosine deaminase (ADA) activities in lymphocytes from rats supplemented or not with curcumin 30 days prior to experimental infection with Trypanosoma evansi. Thirty-two adult male Wistar rats were divided in four groups. The pre-infection group 20 (PreI20) received orally 20 mg/kg of curcumin and pre-infection group 60 (PreI60) received orally 60 mg/kg of curcumin for 30 days prior inoculation with T. evansi. The infected e non-infected control groups received only oral vehicle for 30 days. Trypanosoma evansi infected groups were inoculated intraperitoneally with 0.2 ml of blood with 1 × 106 parasites. After inoculation the treatment of the groups continued until the day of euthanasia (15 days). The results showed that curcumin pre-treatment, with both doses, reduced (P < .05) NTPDase and increased (P < .05) ADA activity in lymphocytes of treated groups when compared to untreated and infected animals (control). The results of this study support the evidence that the regulation of ATP and adenosine levels by NTPDase and ADA activities appear to be important to modulate the immune response in T. evansi infection, once the treatment with curcumin maintained the NTPDase activity reduced and enhanced ADA activity in lymphocytes. It is possible to conclude that the use of curcumin prior to infection with T. evansi induces immunomodulatory effects, favoring the response against the parasite.


Assuntos
Nucleotídeos de Adenina/metabolismo , Adenosina Trifosfatases/metabolismo , Curcumina/metabolismo , Imunomodulação/efeitos dos fármacos , Tripanossomíase/metabolismo , Ração Animal/análise , Animais , Curcumina/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Linfócitos/parasitologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Trypanosoma/fisiologia
4.
Commun Biol ; 2: 152, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31044177

RESUMO

Metabolic reprogramming is an important feature of host-pathogen interactions and a hallmark of tumorigenesis. The intracellular apicomplexa parasite Theileria induces a Warburg-like effect in host leukocytes by hijacking signaling machineries, epigenetic regulators and transcriptional programs to create a transformed cell state. The molecular mechanisms underlying host cell transformation are unclear. Here we show that a parasite-encoded prolyl-isomerase, TaPin1, stabilizes host pyruvate kinase isoform M2 (PKM2) leading to HIF-1α-dependent regulation of metabolic enzymes, glucose uptake and transformed phenotypes in parasite-infected cells. Our results provide a direct molecular link between the secreted parasite TaPin1 protein and host gene expression programs. This study demonstrates the importance of prolyl isomerization in the parasite manipulation of host metabolism.


Assuntos
Proteínas de Transporte/genética , Transformação Celular Neoplásica/genética , Interações Hospedeiro-Patógeno/genética , Proteínas de Membrana/genética , Peptidilprolil Isomerase de Interação com NIMA/genética , Proteínas de Protozoários/genética , Theileria/genética , Hormônios Tireóideos/genética , Animais , Antiprotozoários/farmacologia , Transporte Biológico , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/metabolismo , Bovinos , Linhagem Celular Transformada , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica , Glucose/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Linfócitos/efeitos dos fármacos , Linfócitos/enzimologia , Linfócitos/parasitologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Redes e Vias Metabólicas/genética , Peptidilprolil Isomerase de Interação com NIMA/antagonistas & inibidores , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Naftoquinonas/farmacologia , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Theileria/efeitos dos fármacos , Theileria/enzimologia , Theileria/crescimento & desenvolvimento , Hormônios Tireóideos/metabolismo , Proteínas de Ligação a Hormônio da Tireoide
5.
Parasitol Res ; 118(5): 1479-1491, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30798368

RESUMO

Toxoplasma gondii has the ability to infect various nucleated cell types in different hosts. The aim of the present study was to investigate which chicken blood cells were targeted by T. gondii in a mixed blood cell culture similar to in vivo conditions and to evaluate parasite-host cell interactions. The study consisted of two subsequent experiments. In experiment 1, we applied T. gondii tachyzoites (ME49) at a multiplicity of infection of 1 tachyzoite per blood cell and examined parasite replication, cytokine, and inducible nitric oxide synthase (iNOS) mRNA expression between 1 h and 48 h post-infection (p.i.) by quantitative PCR. By using T. gondii RH-GFP tachyzoites expressing the green fluorescent protein (GFP) in experiment 2, we aimed for visualizing infected cells by confocal laser scanning microscopy (CLSM) and flow cytometric analysis at 24 h p.i. The parasite replication curve showed a massive decrease of parasite stages until 24 h p.i. followed by an approximately plateau phase. We observed mainly significantly increased iNOS mRNA expression levels in T. gondii-infected culture compared to uninfected cells. Flow cytometry and CLSM data confirmed monocytes/macrophages as main target cells for T. gondii. Moreover, different lymphocytes like B cells and cytotoxic T cells seem to be targeted to a low extent. Our findings indicate that monocytes/macrophages play a key role during T. gondii infection in chicken as host cells and triggering of immune response. To the best of our knowledge, this is the first report of a mixed chicken blood cell culture experimentally infected with T. gondii.


Assuntos
Galinhas/parasitologia , Linfócitos/parasitologia , Macrófagos/parasitologia , Toxoplasma/crescimento & desenvolvimento , Animais , Citocinas/biossíntese , Citocinas/genética , Citometria de Fluxo , Interações Hospedeiro-Parasita , Microscopia Confocal , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Reação em Cadeia da Polimerase em Tempo Real , Toxoplasma/genética
7.
Parasitol Res ; 116(8): 2159-2166, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28560572

RESUMO

Apoptosis of infected host macrophages by Leishmania spp. is mainly addressed as one of the survival mechanisms of the parasite. However, there is no eligible data about whether tumor suppressor p53 could induce the apoptosis of host lymphocytes-treated Leishmania major via the mitochondrial intrinsic pathway. In this study, the amastigotes of L. major obtained from ten cutaneous leishmaniases (CL) patients were separately isolated and cultured in N.N.N and RPMI 1640 media. L. major was definitely confirmed by targeting Cyt b gene following sequencing. Subsequently, 2-3 × 106 lymphocytes obtained from ten healthy individuals were isolated and co-cultured with 1-2 × 106 L. major promastigotes. Following 6 h of exposure time, the enzymatic activity of caspase-3 was determined by fluorometric assay in each L. major-treated lymphocytes and cell control (only lymphocyte). The mRNA expressions of Bax, Bcl-2, p53, and caspase-3 genes were assessed by quantitative real-time-PCR analysis following 6 to 9 h of exposure times. The Bcl-2 mRNA expression in L. major-treated lymphocytes was 100-fold down-regulated relative to cell control. The mRNA expressions of p53 and caspase-3 were over-expressed 1.8- and 3.2-fold up-regulated relative to control lymphocytes, respectively. The Bax/Bcl-2 ratio and caspase-3 activity were higher than the control group (Pv <0.05). The current new findings indicate that the apoptotic effects of L. major-treated host lymphocytes dependent on p53 tumor suppressor via mitochondrial pathway may probably address as an auxiliary survival mechanism of L. major in CL patients. However, here is much work ahead to figure out the multiple functions played by apoptosis in the evasion of L. major.


Assuntos
Apoptose , Caspase 3/metabolismo , Leishmania major/fisiologia , Leishmaniose Cutânea/parasitologia , Linfócitos/parasitologia , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo , Adolescente , Adulto , Animais , Apoptose/efeitos dos fármacos , Criança , Ativação Enzimática , Feminino , Humanos , Leishmaniose Cutânea/enzimologia , Masculino , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Adulto Jovem , Proteína X Associada a bcl-2/genética
8.
Sci Rep ; 7(1): 2343, 2017 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-28539607

RESUMO

Liver granulomatous inflammation and fibrosis were the primary pathological changes observed during Schistosoma japonicum (S. japonicum) infection. In the present study, the characteristics of IL-9 were investigated in the liver of S. japonicum infection C57BL/6 mice. Immunofluorescence, qRT-PCR, and ELISA results demonstrated that the expression of IL-9 significantly increased after infection (P < 0.01). FACS results indicated that the peak of IL-9+ Th9 cells in the liver mononuclear cells appeared at the early phase of infection (week 5), except that Th9 cells, CD8+ Tc cells, NKT and γδT cells could secrete IL-9 in this model. Although IL-9 neutralization has a limited effect on liver granulomatous inflammation, it could decrease the level of fibrosis-associated factor, PC-III, in the serum of infected mice (P < 0.05). Taken together, our results indicated that IL-9 was an important type of cytokine involved in the progression of S. japonicum infection-induced hepatic damage.


Assuntos
Interleucina-9/genética , Fígado/metabolismo , Fígado/parasitologia , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/parasitologia , Animais , Células Cultivadas , Feminino , Expressão Gênica , Granuloma/genética , Granuloma/metabolismo , Granuloma/parasitologia , Interações Hospedeiro-Parasita , Inflamação/genética , Inflamação/metabolismo , Inflamação/parasitologia , Interleucina-9/sangue , Interleucina-9/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/parasitologia , Linfócitos/metabolismo , Linfócitos/parasitologia , Camundongos Endogâmicos C57BL , Esquistossomose Japônica/genética , Esquistossomose Japônica/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Auxiliares-Indutores/parasitologia
9.
Mucosal Immunol ; 9(1): 275-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26129648

RESUMO

Group 2 innate lymphoid cells (ILC2s) have an important role in acute allergic lung inflammation. Given their distribution and function, lung ILC2s are hypothesized to coordinate epithelial responses to the external environment; however, how barrier surveillance is linked to ILC2 activation remains unclear. Here, we demonstrate that alveolar type II cells are the main source of interleukin (IL)-33 and thymic stromal lymphopoietin (TSLP) generated in response to chitin or migratory helminths. IL-33 and TSLP synergistically induce an interferon regulatory factor 4 (IRF4)-IL-9 program in ILC2s, and autocrine IL-9 promotes rapid IL-5 and IL-13 production required for optimal epithelial responses in the conducting airways. Thus, ILC2s link alveolar function to regulation of airway flow, revealing a key interaction between resident lymphoid and structural cells that might underlie similar organizational hierarchies in other organs.


Assuntos
Células Epiteliais/imunologia , Fatores Reguladores de Interferon/imunologia , Interleucina-9/imunologia , Linfócitos/imunologia , Pneumonia/imunologia , Infecções por Strongylida/imunologia , Animais , Líquido da Lavagem Broncoalveolar/química , Quitina , Citocinas/genética , Citocinas/imunologia , Células Epiteliais/parasitologia , Regulação da Expressão Gênica , Imunidade Inata , Fatores Reguladores de Interferon/genética , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-33/genética , Interleucina-33/imunologia , Interleucina-5/genética , Interleucina-5/imunologia , Interleucina-9/genética , Pulmão/imunologia , Pulmão/parasitologia , Linfócitos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nippostrongylus/imunologia , Nippostrongylus/parasitologia , Pneumonia/induzido quimicamente , Pneumonia/genética , Pneumonia/patologia , Cultura Primária de Células , Mucosa Respiratória/imunologia , Mucosa Respiratória/parasitologia , Transdução de Sinais , Infecções por Strongylida/genética , Infecções por Strongylida/parasitologia , Infecções por Strongylida/patologia , Linfopoietina do Estroma do Timo
10.
J Exp Med ; 212(6): 875-82, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25964370

RESUMO

Group 2 innate lymphoid cells (ILC2s) are often found associated with mucosal surfaces where they contribute to protective immunity, inappropriate allergic responses, and tissue repair. Although we know they develop from a common lymphoid progenitor in the bone marrow (BM), the specific lineage path and transcriptional regulators that are involved are only starting to emerge. After ILC2 gene expression analysis we investigated the role of Bcl11b, a factor previously linked to T cell commitment, in ILC2 development. Using combined Bcl11b-tom and Id2-gfp reporter mice, we show that Bcl11b is expressed in ILC2 precursors in the BM and maintained in mature ILC2s. In vivo deletion of Bcl11b, by conditional tamoxifen-induced depletion or by Bcl11b(-/-) fetal liver chimera reconstitution, demonstrates that ILC2s are wholly dependent on Bcl11b for their development. Notably, in the absence of Bcl11b there is a concomitant expansion of the RORγt(+) ILC3 population, suggesting that Bcl11b may negatively regulate this lineage. Using Nippostrongylus brasiliensis infection, we reveal that the absence of Bcl11b leads to impaired worm expulsion, caused by a deficit in ILC2s, whereas Citrobacter rodentium infection is cleared efficiently. These data clearly establish Bcl11b as a new factor in the differentiation of ILC2s.


Assuntos
Linfócitos/citologia , Proteínas Repressoras/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/microbiologia , Células da Medula Óssea/parasitologia , Linhagem da Célula , Citrobacter rodentium , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Humanos , Fígado/embriologia , Linfócitos/microbiologia , Linfócitos/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nippostrongylus
11.
Gastroenterology ; 148(7): 1417-26, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25747597

RESUMO

BACKGROUND & AIMS: Intraepithelial lymphocytes that express the γδ T-cell receptor (γδ IELs) limit pathogen translocation across the intestinal epithelium by unknown mechanisms. We investigated whether γδ IEL migration and interaction with epithelial cells promote mucosal barrier maintenance during enteric infection. METHODS: Salmonella typhimurium or Toxoplasma gondii were administered to knockout (KO) mice lacking either the T cell receptor δ chain (Tcrd) or CD103, or control TcrdEGFP C57BL/6 reporter mice. Intravital microscopy was used to visualize migration of green fluorescent protein (GFP)-tagged γδ T cells within the small intestinal mucosa of mice infected with DsRed-labeled S typhimurium. Mixed bone marrow chimeras were generated to assess the effects of γδ IEL migration on early pathogen invasion and chronic systemic infection. RESULTS: Morphometric analyses of intravital video microscopy data showed that γδ IELs rapidly localized to and remained near epithelial cells in direct contact with bacteria. Within 1 hour, greater numbers of T gondii or S typhimurium were present within mucosae of mice with migration-defective occludin KO γδ T cells, compared with controls. Pathogen invasion in Tcrd KO mice was quantitatively similar to that in mice with occludin-deficient γδ T cells, whereas invasion in CD103 KO mice, which have increased migration of γδ T cells into the lateral intercellular space, was reduced by 63%. Consistent with a role of γδ T-cell migration in early host defense, systemic salmonellosis developed more rapidly and with greater severity in mice with occludin-deficient γδ IELs, relative to those with wild-type or CD103 KO γδ IELs. CONCLUSIONS: In mice, intraepithelial migration to epithelial cells in contact with pathogens is essential to γδ IEL surveillance and immediate host defense. γδ IEL occludin is required for early surveillance that limits systemic disease.


Assuntos
Translocação Bacteriana , Quimiotaxia de Leucócito , Células Epiteliais/imunologia , Mucosa Intestinal/imunologia , Linfócitos/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Salmonelose Animal/imunologia , Salmonella typhimurium/patogenicidade , Toxoplasmose Animal/imunologia , Animais , Antígenos CD/genética , Transplante de Medula Óssea , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/parasitologia , Interações Hospedeiro-Patógeno , Imunidade Inata , Cadeias alfa de Integrinas/deficiência , Cadeias alfa de Integrinas/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/parasitologia , Linfócitos/metabolismo , Linfócitos/microbiologia , Linfócitos/parasitologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ocludina/deficiência , Ocludina/efeitos dos fármacos , Permeabilidade , Receptores de Antígenos de Linfócitos T gama-delta/deficiência , Receptores de Antígenos de Linfócitos T gama-delta/efeitos dos fármacos , Salmonelose Animal/genética , Salmonelose Animal/metabolismo , Salmonelose Animal/microbiologia , Salmonella typhimurium/imunologia , Fatores de Tempo , Toxoplasmose Animal/genética , Toxoplasmose Animal/parasitologia , Quimeras de Transplante , Virulência
12.
Rev Chilena Infectol ; 31(5): 549-54, 2014 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-25491453

RESUMO

INTRODUCTION: During malaria infection, both parasite and host are under the effects of oxidative stress due to the increased production of reactive oxygen species, which can induce DNA damage by its genotoxic effects. OBJECTIVE: To evaluate genotoxic effects in human lymphocytes in a cohort of patients with malaria from Medellin and Quibdó. METHODS: We performed an observational cross sectional study in 100 individuals with malaria and 100 healthy controls. Patients infected with Plasmodium consulting the Institute Colombiano of Medicina Tropical of Medellin and the Hospital Ismael Roldán Valencia of Quibdó were included. Genotoxic effects (genetic damage) was analysed by electrophoresis using alkaline single cell gel (Commet assay). RESULTS: The average of tail length of malaria samples (26.9±9.8) was significantly higher than of controls (14.8±3.2) (p<0.01). CONCLUSION: In our study population, malaria infection was associated with increased genotoxicity, while other variables such as smoking, antimalarial treatment, and occupation were not.


Assuntos
Dano ao DNA/genética , Linfócitos/parasitologia , Malária Falciparum/genética , Malária Vivax/genética , Estresse Oxidativo/genética , Estudos de Casos e Controles , Colômbia , Estudos Transversais , Feminino , Humanos , Malária Falciparum/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Masculino , Plasmodium falciparum , Plasmodium vivax , Fatores de Risco , Fumar
13.
Rev. chil. infectol ; Rev. chil. infectol;31(5): 549-554, oct. 2014. graf, tab
Artigo em Espanhol | LILACS | ID: lil-730271

RESUMO

Introduction: During malaria infection, both parasite and host are under the effects of oxidative stress due to the increased production of reactive oxygen species, which can induce DNA damage by its genotoxic effects. Objective: To evaluate genotoxic effects in human lymphocytes in a cohort of patients with malaria from Medellin and Quibdó. Methods: We performed an observational cross sectional study in 100 individuals with malaria and 100 healthy controls. Patients infected with Plasmodium consulting the Institute Colombiano of Medicina Tropical of Medellin and the Hospital Ismael Roldán Valencia of Quibdó were included. Genotoxic effects (genetic damage) was analysed by electrophoresis using alkaline single cell gel (Commet assay). Results: The average of tail length of malaria samples (26.9 ± 9.8) was significantly higher than of controls (14.8 ± 3.2) (p < 0.01). Conclusion: In our study population, malaria infection was associated with increased genotoxicity, while other variables such as smoking, antimalarial treatment, and occupation were not.


Introducción: Durante la infección de la malaria, tanto el parásito como el hospedero están bajo los efectos de estrés oxidativo, dado que se aumenta la producción de especies reactivas del oxígeno, las cuales pueden inducir daños en el ADN debido a su gran efecto genotóxico. Objetivo: Evaluar el efecto genotóxico en linfocitos humanos en una cohorte de pacientes con malaria de Medellín y Quibdó. Métodos: Se realizó un estudio observacional transversal en 100 personas con malaria y 100 controles sanos. Se incluyeron pacientes infectados con Plasmodium, que consultaron en el Instituto Colombiano de Medicina Tropical de Medellín y el Hospital Ismael Roldán Valencia de Quibdó. Se realizó una valoración transversal del efecto (daño genético) mediante electro-foresis en gel de células individuales (ensayo Cometa). Resultados: El promedio de longitud de la cola de los pacientes (26,9 ± 9,8) fue significativamente mayor que la media de los controles sanos (14,8 ± 3,2) (p < 0,01). Conclusión: Se evidenció en la población de estudio que la infección por malaria generó genotoxicidad, no así variables como tabaquismo, tratamiento antimalárico y ocupación.


Assuntos
Feminino , Humanos , Masculino , Dano ao DNA/genética , Linfócitos/parasitologia , Malária Falciparum/genética , Malária Vivax/genética , Estresse Oxidativo/genética , Estudos de Casos e Controles , Colômbia , Estudos Transversais , Malária Falciparum/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Plasmodium falciparum , Plasmodium vivax , Fatores de Risco , Fumar
14.
Bioorg Med Chem ; 22(15): 4338-46, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24909679

RESUMO

East Coast fever (ECF) is a tick-borne disease caused by the parasite Theileria parva which infects cattle. In Sub-Saharan Africa it leads to enormous economic costs. After a bite of a tick, sporozoites invade the host lymphocytes and develop into schizonts. At this stage the parasite transforms host lymphocytes resulting in the clonal expansion of infected lymphocytes. Animals develop a lymphoma like disorder after infection which is rapidly fatal. Hitherto, a few drugs of the quinone type can cure the disease. However, therapy can only be successful after early diagnosis. The genera Theileria and Plasmodium, which includes the causative agent of human malaria, are closely related apicomplexan parasites. Enzymes of the hypusine pathway, a posttranslational modification in eukaryotic initiation factor EIF-5A, have shown to be druggable targets in Plasmodium. We identified the first enzyme of the hypusine pathway from T. parva, the deoxyhypusine synthase (DHS), which is located on chromosome 2 of the Muguga strain. Transcription is significantly increased in schizonts. The expressed T. parva DHS reveals an open reading frame (ORF) of 370 amino acids after expression in Escherichia coli Rosetta cells with a molecular size of 41.26 kDa and a theoretical pI of 5.26. Screening of the Malaria Box which consists of 400 active compounds resulted in a novel heterocyclic compound with a guanyl spacer which reduced the activity of T. parva DHS to 45%. In sum, the guanyl residue seems to be an important lead structure for inhibition of Theileria DHS. Currently, more different guanyl analogues from the Malaria Box are tested in inhibitor experiments to determine their efficacy.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH/antagonistas & inibidores , Plasmodium/enzimologia , Theileria parva/enzimologia , Sequência de Aminoácidos , Animais , Bovinos , Clonagem Molecular , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Escherichia coli/metabolismo , Guanina/química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/metabolismo , Humanos , Cinética , Linfócitos/parasitologia , Dados de Sequência Molecular , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Plasmodium/genética , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Theileria parva/genética
15.
Infect Immun ; 82(5): 1786-92, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24549329

RESUMO

Theileria parva is a tick-transmitted apicomplexan parasite that infects cattle and African buffalo. In cattle, it causes a fatal lymphoproliferative disease called East Coast fever. The polymorphic immunodominant molecule (PIM) is expressed by two stages of the parasite: the sporozoite, which is inoculated by the tick to infect mammalian lymphocytes, and the schizont, the established intralymphocytic stage. Here, we demonstrate that monoclonal antibodies (MAb) to PIM can reduce the ability of sporozoites to infect bovine lymphocytes in vitro. This reduction appears to be due to blocking of sporozoite attachment by binding of the MAb to several regions of PIM. Interestingly, one MAb, which recognizes an epitope in the central variable region of PIM, did not inhibit sporozoite infectivity. We also demonstrate that PIM antigen, as a recombinant molecule, can also reduce sporozoite infectivity in vitro by blocking both attachment and internalization of sporozoites. Electron microscopic studies showed that PIM is present in microspheres below the sporozoite surface and is transported to the parasite surface soon after contact with bovine lymphocytes. The results suggest that at least two sporozoite molecules, PIM and the previously described p67, are involved in the entry of T. parva into mammalian lymphocytes.


Assuntos
Antígenos de Protozoários/metabolismo , Bovinos , Regulação da Expressão Gênica/fisiologia , Linfócitos/parasitologia , Proteínas de Protozoários/metabolismo , Esporozoítos/fisiologia , Theileria parva/fisiologia , Animais , Anticorpos Monoclonais , Antígenos de Protozoários/genética , Transporte Proteico , Proteínas de Protozoários/genética
16.
PLoS One ; 8(10): e76996, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24116194

RESUMO

Theileria equi has a biphasic life cycle in horses, with a period of intraleukocyte development followed by patent erythrocytic parasitemia that causes acute and sometimes fatal hemolytic disease. Unlike Theileria spp. that infect cattle (Theileria parva and Theileria annulata), the intraleukocyte stage (schizont) of Theileria equi does not cause uncontrolled host cell proliferation or other significant pathology. Nevertheless, schizont-infected leukocytes are of interest because of their potential to alter host cell function and because immune responses directed against this stage could halt infection and prevent disease. Based on cellular morphology, Theileria equi has been reported to infect lymphocytes in vivo and in vitro, but the specific phenotype of schizont-infected cells has yet to be defined. To resolve this knowledge gap in Theileria equi pathogenesis, peripheral blood mononuclear cells were infected in vitro and the phenotype of infected cells determined using flow cytometry and immunofluorescence microscopy. These experiments demonstrated that the host cell range of Theileria equi was broader than initially reported and included B lymphocytes, T lymphocytes and monocyte/macrophages. To determine if B and T lymphocytes were required to establish infection in vivo, horses affected with severe combined immunodeficiency (SCID), which lack functional B and T lymphocytes, were inoculated with Theileria equi sporozoites. SCID horses developed patent erythrocytic parasitemia, indicating that B and T lymphocytes are not necessary to complete the Theileria equi life cycle in vivo. These findings suggest that the factors mediating Theileria equi leukocyte invasion and intracytoplasmic differentiation are common to several leukocyte subsets and are less restricted than for Theileria annulata and Theileria parva. These data will greatly facilitate future investigation into the relationships between Theileria equi leukocyte tropism and pathogenesis, breed susceptibility, and strain virulence.


Assuntos
Linfócitos B/imunologia , Linfócitos/imunologia , Macrófagos/imunologia , Linfócitos T/imunologia , Theileria/imunologia , Theileriose/imunologia , Animais , Linfócitos B/parasitologia , Eritrócitos/imunologia , Eritrócitos/parasitologia , Citometria de Fluxo , Cavalos , Interações Hospedeiro-Parasita/imunologia , Imunofenotipagem , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/parasitologia , Linfócitos/parasitologia , Macrófagos/parasitologia , Microscopia de Fluorescência , Parasitemia/imunologia , Parasitemia/parasitologia , Esquizontes/imunologia , Esquizontes/fisiologia , Imunodeficiência Combinada Severa/sangue , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Imunodeficiência Combinada Severa/parasitologia , Especificidade da Espécie , Esporozoítos/imunologia , Esporozoítos/fisiologia , Linfócitos T/parasitologia , Theileria/fisiologia , Theileria annulata/imunologia , Theileria annulata/fisiologia , Theileria parva/imunologia , Theileria parva/fisiologia , Theileriose/parasitologia
17.
Adv Exp Med Biol ; 785: 9-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23456833

RESUMO

The family of innate lymphoid cells (ILCs) comprises of natural killer (NK) cells, Rorγt-dependent ILCs (lymphoid tissue inducer (LTi) cells, ILC22, and ILC17), and type 2 ILCs. Apart from a common requirement for inhibitor of DNA binding 2 (Id2) expression and common γ-chain (γc) signaling, the differentiation of ILC populations is regulated by distinct transcription factors. ILCs play fundamental roles in processes such as cytotoxicity, lymphoid organogenesis, intestinal homeostasis, immunity against infections, and wound healing. However, the dysregulation of ILCs has been implicated in autoimmune and inflammatory diseases. Here, we will review the recent advances in ILC development and their roles in immunity and disease, with a primary focus on type 2 ILCs.


Assuntos
Helmintíase/imunologia , Imunidade Inata , Proteína 2 Inibidora de Diferenciação/imunologia , Linfócitos/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Animais , Diferenciação Celular , Citocinas/biossíntese , Citocinas/imunologia , Citotoxicidade Imunológica , Expressão Gênica/imunologia , Helmintíase/parasitologia , Helmintos/imunologia , Humanos , Imunofenotipagem , Proteína 2 Inibidora de Diferenciação/genética , Linfócitos/classificação , Linfócitos/parasitologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Transdução de Sinais
18.
PLoS One ; 7(9): e45766, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23049855

RESUMO

Visceral leishmaniasis (VL) is one of the most important parasitic diseases with approximately 350 million people at risk. Due to the non availability of an ideal drug, development of a safe, effective, and affordable vaccine could be a solution for control and prevention of this disease. In this study, a potential Th1 stimulatory protein- Triose phosphate isomerase (TPI), a glycolytic enzyme, identified through proteomics from a fraction of Leishmania donovani soluble antigen ranging from 89.9-97.1 kDa, was assessed for its potential as a suitable vaccine candidate. The protein- L. donovani TPI (LdTPI) was cloned, expressed and purified which exhibited the homology of 99% with L. infantum TPI. The rLdTPI was further evaluated for its immunogenicity by lymphoproliferative response (LTT), nitric oxide (NO) production and estimation of cytokines in cured Leishmania patients/hamster. It elicited strong LTT response in cured patients as well as NO production in cured hamsters and stimulated remarkable Th1-type cellular responses including IFN-ã and IL-12 with extremely lower level of IL-10 in Leishmania-infected cured/exposed patients PBMCs in vitro. Vaccination with LdTPI-DNA construct protected naive golden hamsters from virulent L. donovani challenge unambiguously (∼90%). The vaccinated hamsters demonstrated a surge in IFN-ã, TNF-á and IL-12 levels but extreme down-regulation of IL-10 and IL-4 along with profound delayed type hypersensitivity and increased levels of Leishmania-specific IgG2 antibody. Thus, the results are suggestive of the protein having the potential of a strong candidate vaccine.


Assuntos
Leishmania donovani/enzimologia , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/parasitologia , Triose-Fosfato Isomerase/química , Animais , Linhagem Celular , Proliferação de Células , Clonagem Molecular , Cricetinae , Citocinas/metabolismo , Feminino , Glicólise , Humanos , Imunoglobulina G/química , Interferon-alfa/metabolismo , Interleucina-12/metabolismo , Interleucina-4/metabolismo , Leucócitos Mononucleares/enzimologia , Linfócitos/citologia , Linfócitos/parasitologia , Masculino , Mesocricetus , Óxido Nítrico/química , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Triose-Fosfato Isomerase/imunologia
19.
Histol Histopathol ; 27(8): 1109-20, 2012 08.
Artigo em Inglês | MEDLINE | ID: mdl-22763883

RESUMO

Schistosoma mansoni synthesizes glycoconjugates which interact with galectin-3, eliciting an intense humoral immune response. Moreover, it was demonstrated that galectin-3 regulates B cell differentiation into plasma cells. Splenomegaly is a hallmark event characterized by polyclonal B cell activation and enhancement of antibody production. Here, we investigated whether galectin-3 interferes with spleen organization and B cell compartment during chronic schistosomiasis, using wild type (WT) and galectin-3-/- mice. In chronically-infected galectin-3-/- mice the histological architecture of the spleen, including white and red pulps, was disturbed with heterogeneous lymphoid follicles, an increased number of plasma cells (CD19-B220-/lowCD138+) and a reduced number of macrophages (CD19-B220-Mac-1+CD138-) and B lymphocytes (CD19+B220+/highCD138-), compared with the WT infected mice. In the absence of galectin-3 there was an increase of annexin-V+PI- cells and a major presence of apoptotic cells in spleen compared with WT infected mice. In spleen of WT infected mice galectin-3 was largely expressed in lymphoid follicles and extrafollicular sites. Thus, we propose that galectin-3 plays a role in splenic architecture, controlling distinct events such as apoptosis, macrophage activity, B cell differentiation and plasmacytogenesis in the course of S. mansoni infection.


Assuntos
Galectina 3/fisiologia , Doenças Parasitárias em Animais/patologia , Schistosoma mansoni/patogenicidade , Esquistossomose mansoni/patologia , Esplenopatias/patologia , Animais , Apoptose , Linfócitos B/citologia , Linfócitos B/metabolismo , Diferenciação Celular , Doença Crônica , Modelos Animais de Doenças , Feminino , Galectina 3/deficiência , Granuloma/patologia , Interações Hospedeiro-Patógeno , Imunofenotipagem , Linfócitos/parasitologia , Linfócitos/patologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças Parasitárias em Animais/imunologia , Doenças Parasitárias em Animais/parasitologia , Plasmócitos/metabolismo , Plasmócitos/parasitologia , Plasmócitos/patologia , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Esplenopatias/imunologia , Esplenopatias/parasitologia
20.
Int Immunopharmacol ; 11(11): 1668-79, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21875692

RESUMO

Leishmaniasis is caused by protozoan parasites of the genus Leishmania and causes a wide spectrum of clinical manifestations ranging from self-healing cutaneous lesions to the fatal visceral form. The use of pentavalent antimony, the mainstay of therapy of Leishmaniasis is now limited by its toxicity and alarming increase in unresponsiveness, especially in the Indian subcontinent. Furthermore, other anti-leishmanial drugs are unaffordable in many affected countries and as vaccination based approaches have not yet proved to be effective, chemotherapy remains the only alternative, emphasizing the need for identifying novel drug targets. In this review, we have described the different host immune signaling pathways that could be considered as potential drug targets for Leishmania chemotherapy.


Assuntos
Antiprotozoários/uso terapêutico , Interações Hospedeiro-Parasita/imunologia , Imunomodulação , Leishmaniose/tratamento farmacológico , Leishmaniose/imunologia , Animais , Antiprotozoários/administração & dosagem , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/parasitologia , Humanos , Leishmania/efeitos dos fármacos , Leishmania/fisiologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/parasitologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/parasitologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/parasitologia
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