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1.
Eur J Paediatr Dent ; 24(2): 104-111, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37140171

RESUMO

AIM: Parents and caregivers, particularly in Italy, often have limited knowledge about their children's oral health. The primary objective of the study is to evaluate the educational effectiveness of a book on nutrition and prevention of oral diseases entitled "Oral health of mother and child in the first 1000 days of life". MATERIALS: The sample for this study was composed of 103 adult Italian women who were potential caregivers of one or more children (e.g., mothers, grandmothers, babysitters, and educators). The enrolled women completed a preliminary online survey which included questions about their socio-demographic characteristics and their knowledge on oral health in the first 1000 days of life of newborns (30 questions). Following the survey, they received the educational book. After reading it, the participants completed a second online survey with the same 30 questions, to measure any improvement in their knowledge. CONCLUSION: It appears that our educational book about nutrition and prevention of oral diseases was effective in enhancing knowledge among the participants in our study. These findings suggest that this educational resource has the potential to be a valuable tool in preventing oral diseases in paediatric populations. However, further confirmation of these results should be obtained through randomised controlled trials.


Assuntos
Saúde Bucal , Pais , Adulto , Criança , Humanos , Recém-Nascido , Feminino , Escolaridade , Mães , Livros
2.
Sci Rep ; 12(1): 19287, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369463

RESUMO

To analyze the performance of ultra-wide-field (UWF) fundus photography compared with ophthalmoscopy in identifying and classifying retinal diseases. Patients examined for presumed major retinal disorders were consecutively enrolled. Each patient underwent indirect ophthalmoscopic evaluation, with scleral depression and/or fundus biomicroscopy, when clinically indicated, and mydriatic UWF fundus imaging by means of CLARUS 500™ fundus camera. Each eye was classified by a clinical grader and two image graders in the following groups: normal retina, diabetic retinopathy, vascular abnormalities, macular degenerations and dystrophies, retinal and choroidal tumors, peripheral degenerative lesions and retinal detachment and myopic alterations. 7024 eyes of new patients were included. The inter-grader agreement for images classification was perfect (kappa = 0.998, 95% Confidence Interval (95%CI) = 0.997-0.999), as the two methods concordance for retinal diseases diagnosis (kappa = 0.997, 95%CI = 0.996-0.999) without statistically significant difference. UWF fundus imaging might be an alternative to ophthalmoscopy, since it allows to accurately classify major retinal diseases, widening the range of disorders possibly diagnosed with teleophthalmology. Although the clinician should be aware of the possibility that a minority of the most peripheral lesions may be not entirely visualized, it might be considered a first line diagnostic modality, in the context of a full ophthalmological examination.


Assuntos
Retinopatia Diabética , Oftalmologia , Doenças Retinianas , Telemedicina , Humanos , Oftalmoscopia/métodos , Fotografação/métodos , Fundo de Olho , Doenças Retinianas/diagnóstico por imagem , Retinopatia Diabética/diagnóstico
3.
J Appl Genet ; 63(2): 423-428, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35279801

RESUMO

Analysis of the SARS-CoV-2 transcriptome has revealed a background of low-frequency intra-host genetic changes with a strong bias towards transitions. A similar pattern is also observed when inter-host variability is considered. We and others have shown that the cellular RNA editing machinery based on ADAR and APOBEC host-deaminases could be involved in the onset of SARS-CoV-2 genetic variability. Our hypothesis is based both on similarities with other known forms of viral genome editing and on the excess of transition changes, which is difficult to explain with errors during viral replication. Zong et al. criticize our analysis on both conceptual and technical grounds. While ultimate proof of an involvement of host deaminases in viral RNA editing will depend on experimental validation, here, we address the criticism to suggest that viral RNA editing is the most reasonable explanation for the observed intra- and inter-host variability.


Assuntos
COVID-19 , Edição de RNA , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , COVID-19/genética , Humanos , Edição de RNA/genética , SARS-CoV-2/genética , Transcriptoma/genética
4.
Mediators Inflamm ; 2018: 4283672, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29535593

RESUMO

We aim to investigate some of the pathogenetic mediators of the human echinococcosis and to obtain updated epidemiological findings on cases of echinococcosis in Calabria, Southern Italy. Echinococcosis diagnosis was based on imaging, serological investigations, and molecular assay. Indeed, real-time PCR indicated the presence of G2/G3 genotypes of Echinococcus granulosus complex. Regarding pathogenesis, a relevant novel tool of immune depression should be deemed the reduced level of serum MCP-1. Also, we found a previously unreported VEGF, possibly associated with neovascularization requested by the parasite cyst metabolism. Cytokine profiles suggest a bias of the immunity toward Th2 and Treg responses. Nitric oxide levels exhibited a significant decrease one week after therapy versus basal level measured before surgery and/or chemotherapy. An increase of serum total IgE class and IgG4 subclass was found in Echinococcus-positive patients versus controls. Our data demonstrated an endemic spreading, at least in the province of Catanzaro and neighboring Calabria territories, for such parasitosis with the novel issue of the number of female overcoming male cases. In conclusion, the novel findings of this study were the increased VEGF and the reduced serum MCP-1 in the studied cases, as well as the number of Echinococcus-infected females overcoming the infected males.


Assuntos
Quimiocina CCL2/metabolismo , Equinococose/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Equinococose/imunologia , Echinococcus granulosus/imunologia , Echinococcus granulosus/patogenicidade , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th2/imunologia , Células Th2/metabolismo
5.
Parasite Immunol ; 40(4): e12519, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29380393

RESUMO

Manipulation of costimulatory and surface molecules that shape the extent of immune responses by Leishmania is suggested as one of the mechanisms of evading the host's defences. The experiments reported here were designed to evaluate the expressions of CD11b, CD11c, CD14, CD18, CD54, CD80, CD86, CD206, MHC class II and TLR-2 (Toll-like receptor 2) in human macrophages infected with L. amazonensis. Phenotypic evaluation revealed a negative modulation in CD11b, CD11c, CD14, CD18, CD54 and MHC class II molecules, depending on the level of infection. The results showed that as early as 1 hour after infection no reduction in marker expression occurs, whereas after 24 hours, downregulation of these molecules was observed in macrophages. No significant changes were observed in the expressions of CD80, CD86, CD206 and TLR2. Evidence of the differential modulation of markers expression and that after parasite uptake no reduction in surface marker expression occurs indicates that parasite internalization is not involved in the phenomena of down-modulation.


Assuntos
Antígenos CD/biossíntese , Leishmania mexicana/imunologia , Leishmaniose Cutânea/imunologia , Macrófagos/imunologia , Macrófagos/parasitologia , Adulto , Animais , Antígenos CD/imunologia , Antígenos de Superfície/biossíntese , Antígenos de Superfície/imunologia , Antígeno B7-1/biossíntese , Antígeno CD11b/biossíntese , Células Cultivadas , Antígenos de Histocompatibilidade Classe II/biossíntese , Humanos , Leishmaniose Cutânea/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Receptor 2 Toll-Like/biossíntese
6.
J Med Microbiol ; 62(Pt 7): 1081-1085, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23518653

RESUMO

Systemic Bartonella henselae infections are unusual in immunocompetent adults. However, here we report one such case of bartonellosis in a 34-year-old patient, who presented with fever and multinodular splenomegaly. We also describe a novel method of identifying Bartonella henselae by real-time quantitative polymerase chain reaction and sequencing of amplified products. This could prevent splenic bartonellosis being mistaken for lymphoma and thereby avert unnecessary splenectomy.


Assuntos
Infecções por Bartonella/microbiologia , Bartonella henselae/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Esplenopatias/microbiologia , Adulto , Antibacterianos/uso terapêutico , DNA Bacteriano , Feminino , Humanos , Imunocompetência
7.
Scand J Immunol ; 74(2): 165-75, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21517930

RESUMO

Hypoxia (low oxygen tension) is a common feature of inflamed and infected tissues. The influence of hypoxia on macrophage responses to micro-organisms has only recently been studied. This study demonstrates that hypoxia induced macrophages to control Leishmania amazonensis, an intracellular parasite that causes cutaneous and cutaneous metastatic lesions. The mechanisms that contribute to the control of macrophages against L. amazonensis infection under a hypoxic microenvironment are not known. Nitric oxide, TNF-α, IL-10 or IL-12 is not responsible for the decrease in parasitism under hypoxia. Live L. amazonensis entry or exocytosis of internalized particles as well as energetic metabolism was not impaired in infected macrophages; no apoptosis-like death was detected in intracellular parasites. Reactive oxygen species (ROS) is likely to be involved, because treatment with antioxidants N-acetylcysteine (NAC) and ebselen inhibits the leishmanicidal effect of macrophages under hypoxia. Leishmania amazonensis infection induces macrophages to express hypoxia-inducible factor-1 (HIF-1α) and -2 (HIF-2α). Data indicate that hypoxia affects the microbial activities and protein expression of macrophages leading to a different phenotype from that of the normoxic counterpart and that it plays a role in modulating Leishmania infection.


Assuntos
Hipóxia/imunologia , Leishmaniose Cutânea/imunologia , Macrófagos/imunologia , Acetilcisteína/farmacologia , Animais , Azóis/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/imunologia , Feminino , Sequestradores de Radicais Livres/farmacologia , Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Interleucina-10/imunologia , Interleucina-12/imunologia , Isoindóis , Leishmaniose Cutânea/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/imunologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Compostos Organosselênicos/farmacologia , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/imunologia
8.
J Parasitol ; 94(6): 1415-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18576874

RESUMO

Recently, our group demonstrated that mouse lesions infected with Leishmania amazonensis are hypoxic. Evidence indicates the negative impact of hypoxia on the efficacy of a variety of chemotherapeutic agents against tumors, fungi, bacteria, and malaria parasites. In the present study, comparison of the effect of antileishmanial drugs on L. amazonensis-infected macrophages under normoxic and hypoxic conditions was performed. We compared the effect of 5% oxygen tension with a tension of 21% oxygen on peritoneal murine macrophage cultures infected with the parasite and treated with glucantime, amphotericin B, or miltefosine. Analysis of the infection index (percentage of infected macrophages x number of amastigotes per macrophage), dose-dependent efficacy of drugs, and IC(50) values demonstrated that hypoxia conferred a small, but significant, resistance to all 3 antileishmanial drugs. The present finding suggests that in vitro assays under hypoxia should not be neglected in drug studies.


Assuntos
Antiprotozoários/farmacologia , Leishmania mexicana/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Oxigênio/metabolismo , Anfotericina B/farmacologia , Animais , Hipóxia Celular/fisiologia , Relação Dose-Resposta a Droga , Concentração Inibidora 50 , Leishmania mexicana/metabolismo , Macrófagos Peritoneais/metabolismo , Meglumina/farmacologia , Antimoniato de Meglumina , Camundongos , Camundongos Endogâmicos BALB C , Compostos Organometálicos/farmacologia , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacologia
9.
Diagn Microbiol Infect Dis ; 50(3): 159-66, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15541600

RESUMO

Previous studies demonstrated that live Bartonella quintana often induces angioproliferative lesions in humans. It modulates endothelial cell apoptotic and inflammatory patterns, thus inducing a very early overexpression of caspase 8 and Apaf-1 and increasing mRNA production of TNF-alpha, interleukin-8, and E-selectin. However, starting at 10 hours postinfection, the bacteria provoke antiapoptotic effects that induce an increase of bcl-2 gene transcription. To gain further insight into the cellular mechanisms that regulate apoptosis, survival and proliferation, we studied the modulation of mitogen-activated protein kinase (MAPK) and the activation state of cdc2 kinase, which regulates progression into mitosis. Confocal microscopy findings indicated a maximum rate of Bartonella entry into host cells between postinfection hours 6 and 10. Live bacteria caused substantially higher apoptosis of human umbilical vein endothelial cells-cryopreserved (HUVEC-C) than heat- and trypsin-inactivated microorganisms. During the first 6 hours postinfection, B. quintana triggered a peak of apoptosis, induced activation of p38 MAPK and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), with bacterial clusters appearing at the cellular surface of the HUVEC-C. However, at 8 to 24 hours postinfection, B. quintana was internalized and inhibited proapoptotic signals such as p38 MAPK and SAPK/JNK while inducing antiapoptotic signals. Indeed, expression of the bcl-2 gene and the increase of the bcl-2 kinase active form was concomitant to activation of mitosis, as shown by cdc2 protein activation. These data thus suggest that mechanisms that induce mitotic activity and inhibit apoptotic signals may contribute to the ability of B. quintana to cause vascular proliferation.


Assuntos
Apoptose/fisiologia , Bartonella quintana/patogenicidade , Células Endoteliais/citologia , Células Endoteliais/microbiologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitose/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteína Quinase CDC2/fisiologia , Linhagem Celular , Células Endoteliais/enzimologia , Ativação Enzimática , Regulação da Expressão Gênica/fisiologia , Genes bcl-2/fisiologia , Humanos , Fatores de Tempo
10.
Diagn Microbiol Infect Dis ; 45(2): 107-15, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12614981

RESUMO

Bartonella quintana is an epicellular bacterium, which in vivo as well as in vitro, invades endothelial cells and develops within them inducing proliferative effects that play a pivotal role in neovascular manifestation of this disease. We investigated the effect of live Bartonella quintana and its LPS on apoptosis and inflammatory response in HUVEC-C, an endothelial cell line. The kinetics of the programmed cell death of Bartonella quintana-infected HUVEC-C showed a peculiar course. Even if early during infection apoptosis reached a peak after 6 h, later on apoptosis was inhibited. Such apoptosis inhibition was not observed during Bartonella quintana lipopolysaccharide treatment because LPS-stimulated HUVEC-C did progress to cell death. Evaluation of multiple cell signal transduction pathways revealed an overexpression of Apaf 1 and caspase 8 in HUVEC-C after 2 h of infection, and of bcl-2 starting from 10 h post Bartonella quintana infection. Moreover, Bartonella quintana and its LPS showed a different effect on the activation of genes involved in inflammatory response as revealed by molecular analysis of host cells. Bartonella quintana appears to be able to inhibit programmed cell death, inducing intracellular signals leading to survival and proliferation through the bcl-2 gene, despite the early increase of inflammatory status induced in endothelial cells. This mechanism, together with a poor endotoxin ability to stimulate strong inflammatory response, could contribute to the capability of the bacteria to persist intracellularly, causing chronic disease and producing neovascular manifestations.


Assuntos
Apoptose , Bartonella quintana/patogenicidade , Endotélio/microbiologia , Linhagem Celular , Selectina E/isolamento & purificação , Endotélio/citologia , Endotélio/imunologia , Humanos , Inflamação/microbiologia , Interleucina-8/isolamento & purificação , Lipopolissacarídeos/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/isolamento & purificação , Febre das Trincheiras/imunologia , Fator de Necrose Tumoral alfa/isolamento & purificação
11.
Free Radic Biol Med ; 30(11): 1234-42, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11368921

RESUMO

The cytotoxins produced by phagocytic cells lacking peroxidases such as macrophages remain elusive. To elucidate macrophage microbicidal mechanisms in vivo, we compared the lesion tissue responses of resistant (C57Bl/6) and susceptible (BALB/c) mice to Leishmania amazonensis infection. This comparison demonstrated that parasite control relied on lesion macrophage activation with inducible nitric oxide synthase expression (iNOS), nitric oxide synthesis, and extensive nitration of parasites inside macrophage phagolysosomes at an early infection stage. Nitration and iNOS expression were monitored by confocal microscopy; nitric oxide synthesis was monitored by EPR. The main macrophage nitrating agent was shown to be peroxynitrite derived because parasite nitration occurred in the virtual absence of polymorphonuclear cells (monitored as peroxidase activity) and was accompanied by protein hydroxylation (monitored as 3-hydroxytyrosine levels). In vitro studies confirmed that peroxynitrite is cytotoxic to parasites whereas nitric oxide is cytostatic. The results indicate that peroxynitrite is likely to be produced close to the parasites and most of it reacts with carbon dioxide to produce carbonate radical anion and nitrogen dioxide whose concerted action leads to parasite nitration. In parallel, some peroxynitrite decomposition to the hydroxyl radical should occur due to the detection of hydroxylated proteins in the healing tissues. Consequently, peroxynitrite and derived radicals are likely to be important macrophage-derived cytotoxins.


Assuntos
Carbonatos/metabolismo , Radicais Livres/metabolismo , Leishmania infantum/patogenicidade , Leishmaniose/metabolismo , Macrófagos/parasitologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/biossíntese , Ácido Peroxinitroso/metabolismo , Tirosina/análogos & derivados , Animais , Dióxido de Carbono/metabolismo , Cromatografia Líquida de Alta Pressão , Di-Hidroxifenilalanina/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Hidroxilação , Leishmaniose/patologia , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Confocal , Microscopia de Fluorescência , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II , Peroxidase/metabolismo , Tirosina/metabolismo
12.
Rev Inst Med Trop Sao Paulo ; 40(4): 237-40, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9876437

RESUMO

In this study we investigated the effect of 8-Bromoguanosine, an immunostimulatory compound, on the cytotoxicity of macrophages against Leishmania amazonensis in an in vitro system. The results showed that macrophages treated with 8-Bromoguanosine before or after infection are capable to reduce parasite load, as monitored by the number of amastigotes per macrophage and the percentage of infected cells (i.e. phagocytic index). Since 8-Bromoguanosine was not directly toxic to the promastigotes, it was concluded that the ribonucleoside induced macrophage activation. Presumably, 8-Bromoguanosine primed macrophages by inducing interferon alpha and beta which ultimately led to L. amazonensis amastigote killing. The results suggest that guanine ribonucleosides may be useful to treat infections with intracellular pathogens.


Assuntos
Adjuvantes Imunológicos/farmacologia , Morte Celular/efeitos dos fármacos , Guanosina/análogos & derivados , Leishmania , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Animais , Guanosina/farmacologia , Leishmania/efeitos dos fármacos , Camundongos
13.
Rev Soc Bras Med Trop ; 29(5): 419-24, 1996.
Artigo em Português | MEDLINE | ID: mdl-8966306

RESUMO

A study was carried out to identify Leishmania species involved in skin lesions of patients from Cosmópolis and Indaiatuba, State of São Paulo, Brazil. The epidemiological data of cutaneous leishmaniasis in two cities suggested a epidemic situation in 1994. The lesions were clinically characteristic of cutaneous leishmaniasis and five out six patients responded positively to Montenegro's intradermal test. The histopathology of skin lesions were characterized by two patterns: exudative-cellular reaction and exudative granulomatous reaction. The clinical and histopathological parameters suggested Leishmania (Viannia) braziliensis as the possible etiologic agent. In agreement, it was difficult to isolate and maintain the parasite in the laboratory. Characterization by in situ hybridization with kDNA amastigotes from lesions fragments confirmed that Leishmania (Viannia) braziliensis was the parasite responsible for the studied cutaneous lesions.


Assuntos
Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Adulto , Animais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Braz. j. med. biol. res ; 29(7): 853-62, July 1996. ilus, graf
Artigo em Inglês | LILACS | ID: lil-181497

RESUMO

Activated macrophages simultaneously synthesize nitric oxide and superoxide anion which can react with each other producing peroxynitrite. Consequently, it has been difficult to assess the precise contribution of each of the formed reactive oxygen- and nitrogenderived species to the microbicidal activities of macrophages, particularly in vivo. To explore this problem, we are examining the formation and potential roles of nitrogen-derived intermediates in Leishmania amazonensis murine infection. Thus far, our results have demonstrated that peroxynitrite is a potent leishmanicidal agent in vitro and that both nitric oxide and peroxynitrite are formed during infection of susceptible BALB/c mouse strain. Nitric oxide was detected as the nitrosyl-hemoglobin complex by electron paramagnetic resonance analysis of blood drawn from mice at different times of infection, and it was shown to increase with the evolution of the disease. These results will be discussed in the context of the dual physiological role of nitric oxide either as a signaling molecule or as a deleterious agent.


Assuntos
Animais , Camundongos , Técnicas In Vitro , Leishmania mexicana/metabolismo , Leishmaniose/metabolismo , Nitritos/metabolismo , Óxido Nítrico/metabolismo , Peróxidos/metabolismo , Ânions/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Espécies Reativas de Oxigênio/metabolismo , Radicais Livres , Hemoglobinas/biossíntese , Leishmania major/efeitos dos fármacos , Leishmania major/imunologia , Leishmania major/metabolismo , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/imunologia , Leishmaniose/imunologia , Ativação de Macrófagos , Camundongos Endogâmicos BALB C , Nitritos/farmacologia , Nitrogênio/fisiologia , Nitrogênio/metabolismo , Oxidantes/metabolismo , Óxido Nítrico/farmacologia , Óxido Nítrico/fisiologia , Óxido Nítrico/síntese química , Peróxidos/farmacologia , Superóxidos/metabolismo , Tirosina/biossíntese
16.
Infect Immun ; 61(5): 2131-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-7683002

RESUMO

Monoclonal antibodies directed against Leishmania (Leishmania) amazonensis amastigotes were produced. One monoclonal antibody (1C3) selected by indirect immunofluorescence reacted with both amastigotes and promastigotes of L. (L.) amazonensis. Glycolipid extraction from L. (L.) amazonensis amastigotes and separation by high-performance thin-layer chromatography followed by immunoblotting demonstrated that 1C3 reacts with two glycosphingolipids which migrate chromatographically similarly to ceramide-N-acetylneuraminic acid (GM1) and ceramide-N-tetrose-di-acetylneuraminic acid (GD1a). The antibody did not react with glycosphingolipids from L. (L.) amazonensis promastigotes. Immunoprecipitation of 125I- and 35S-methionine-labeled promastigotes demonstrated that 1C3 recognizes gp63 from L. (L.) amazonensis promastigotes. Biosynthetic incorporation of labeled lipids by L. (L.) amazonensis amastigotes indicated that the glycosphingolipids reactive with 1C3 contain oleic acid in their structures. Surface labeling with galactose oxidase and sodium boro[3H]hydride indicated that galactose is present in 1C3-reactive antigens, strongly suggesting that these glycosphingolipids are localized on the surface of L. (L.) amazonensis amastigotes. Inhibition experiments of macrophage infection implicated the 1C3-reactive glycosphingolipids from L. (L.) amazonensis amastigotes in Leishmania invasion. The role of gp63 in promastigote-macrophage attachment was also demonstrated by inhibition experiments performed with 1C3, consistent with data from the literature.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Glicoesfingolipídeos/imunologia , Leishmania mexicana/imunologia , Animais , Antígenos de Protozoários/biossíntese , Antígenos de Protozoários/química , Epitopos , Leishmania mexicana/citologia , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C
17.
Braz. j. med. biol. res ; 23(6/7): 573-6, 1990. ilus
Artigo em Inglês | LILACS | ID: lil-92205

RESUMO

Antigens of the nematode Nippostrongylus brasiliensis were fractionated by SDS-PAGE under reducing conditions, transferred electrophoretically onto nitrocelluose and converted to antigen-bound nitrocellulose particles for use in vitro proliferation assays. Mesenteric lymph node cells from unfected rats were analyzed for reactivity against the fractionated antigens, revealing a range of different molecular weight antigens. Ian addition, when supernatants from these cultures were assyed for IL3, further reactive antigens wee detected. The results demonstrated that these approaches are useful for the identification of T-cell reactive components of a complex mixture of parasite antigens in helminth infections, where the cellular nature of protection is not well defined


Assuntos
Ratos , Animais , Antígenos de Helmintos/imunologia , Técnicas In Vitro , Infecções por Nematoides/imunologia , Nippostrongylus/imunologia , Linfócitos T/fisiologia , Immunoblotting , Linfonodos/citologia , Ratos Wistar
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