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1.
BMC Microbiol ; 20(1): 156, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32527216

RESUMO

BACKGROUND: Interaction of C. albicans with oral bacteria is crucial for its persistence, but also plays a potential role in the infection process. In the oral cavity, it grows as part of dental plaque biofilms. Even though growth and interaction of C. albicans with certain bacterial species has been studied, little is known about its biofilm growth in vitro in the simultaneous presence of Gram-negative and Gram-positive bacteria. The aim was to evaluate the growth of C. albicans in polymicrobial biofilms comprising oral Gram-negative and Gram-positive bacteria. Further, we also aimed to assess the potential of C. albicans in the Candida-bacteria polymicrobial biofilm to elicit cytokine gene expression and cytokine production from human blood cells. RESULTS: C. albicans cell counts increased significantly up to 48 h in polymicrobial biofilms (p < 0.05), while the bacterial counts in the same biofilms increased only marginally as revealed by qPCR absolute quantification. However, the presence of bacteria in the biofilm did not seem to affect the growth of C. albicans. Expression of IL-8 gene was significantly (p < 0.05) higher upon stimulation from biofilm-supernatants than from biofilms in polymicrobial setting. On the contrary, TNF-α expression was significantly higher in biofilms than in supernatants but was very low (1-4 folds) in the monospecies biofilm of C. albicans. ELISA cytokine quantification data was in agreement with mRNA expression results. CONCLUSION: Persistence and enhanced growth of C. albicans in polymicrobial biofilms may imply that previously reported antagonistic effect of A. actinomycetemcomitans was negated. Increased cytokine gene expression and cytokine production induced by Candida-bacteria polymicrobial biofilms and biofilm supernatants suggest that together they possibly exert an enhanced stimulatory effect on IL-8 and TNF-α production from the host.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/fisiologia , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Interleucina-8/genética , Fator de Necrose Tumoral alfa/genética , Sangue/imunologia , Sangue/microbiologia , Candida albicans/imunologia , Humanos , Interleucina-8/metabolismo , Interações Microbianas , Boca/microbiologia , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
2.
J Med Virol ; 89(8): 1435-1441, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28165155

RESUMO

The use of saliva and dried blood spots (DBS) could increase access to HCV diagnosis for high-risk populations, such as HIV-infected individuals, but the performance of these assays has not been well established in this group. This study aims to evaluate HIV status, particularly TCD4+ cell count and viral load, in the performance of anti-HCV testing using DBS and saliva. A total of 961 individuals classified as HCV+, HIV+, or HIV/HCV+, as well as negative controls, donated serum, DBS, and saliva samples for anti-HCV testing using a commercial enzyme immunoassay. Sample volume was modified for DBS and saliva, and an ROC curve was used for cut-off determination in saliva. Anti-HCV sensitivities were greater than 93% using DBS and saliva in the HCV+ group, while they were 83.3% and 95.6% for HCV/HIV+ individuals for DBS and saliva assays, respectively. Specificity varied from 91.7% to 100% using saliva and DBS in HIV monoinfected and control subjects. When only anti-HCV/HCV RNA+ serum samples, that is, true positives, were considered, the sensitivities were 98.3% and 100% for DBS and saliva, respectively, in the HCV+ group and 91.6% and 94.8% for DBS and saliva, respectively, in the HIV/HCV+ group. High absorbance values were observed among those presenting with HCV RNA in serum and low HIV viral load (less than 50 copies/mL). In conclusion, DBS and saliva samples could be used for anti-HCV detection, particularly to identify active HCV cases, but low sensitivity was observed for anti-HCV testing using DBS in the HIV/HCV+ group.


Assuntos
Sangue/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Infecções por HIV/complicações , Anticorpos Anti-Hepatite C/análise , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , Saliva/imunologia , Adulto , Idoso , Contagem de Linfócito CD4 , Dessecação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Inquéritos e Questionários , Carga Viral
3.
J Infect Dis ; 214(5): 722-31, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27247344

RESUMO

BACKGROUND: Tonsils play a key role in eliciting immune responses against respiratory pathogens. Little is known about how tonsils contribute to the local immune response after intranasal vaccination. Here, we uniquely report the mucosal humoral responses in tonsils and saliva after intranasal live attenuated influenza vaccine (LAIV) vaccination in children. METHODS: Blood, saliva, and tonsils samples were collected from 39 children before and after LAIV vaccination and from 16 age-matched, nonvaccinated controls. Serum antibody responses were determined by a hemagglutination inhibition (HI) assay. The salivary immunoglobulin A (IgA) level was measured by an enzyme-linked immunosorbent assay. Antibody-secreting cell (ASC) and memory B-cell (MBC) responses were enumerated in tonsils and blood. RESULTS: Significant increases were observed in levels of serum antibodies and salivary IgA to influenza A(H3N2) and influenza B virus strains as early as 14 days after vaccination but not to influenza A(H1N1). Influenza virus-specific salivary IgA levels correlated with serum HI responses, making this a new possible indicator of vaccine immunogenicity in children. LAIV augmented influenza virus-specific B-cell responses in tonsils and blood. Tonsillar MBC responses correlated with systemic MBC and serological responses. Naive children showed significant increases in MBC counts after LAIV vaccination. CONCLUSIONS: This is the first study to demonstrate that LAIV elicits humoral B-cell responses in tonsils of young children. Furthermore, salivary IgA analysis represents an easy method for measuring immunogenicity after vaccination.


Assuntos
Anticorpos Antivirais/análise , Linfócitos B/imunologia , Vacinas contra Influenza/imunologia , Tonsila Palatina/imunologia , Administração Intranasal , Adolescente , Células Apresentadoras de Antígenos/imunologia , Sangue/imunologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Imunoglobulina A/análise , Vacinas contra Influenza/administração & dosagem , Masculino , Saliva/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
4.
Med Microbiol Immunol ; 205(4): 297-314, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26732075

RESUMO

Toxoplasma gondii infection induces a strong and long-lasting immune response that is able to prevent most reinfections but allows tissue cysts. Irradiated, sterilized T. gondii tachyzoites are an interesting vaccine, and they induce immunity that is similar to infection, but without cysts. In this study, we evaluated the cellular immune response in the blood and spleen of mice immunized with this preparation by mouth (v.o.) or intraperitoneally (i.p.) and analyzed the protection after challenge with viable parasites. BALB/c mice were immunized with three i.p. or v.o. doses of irradiated T. gondii tachyzoites. Oral challenge with ten cysts of the ME-49 or VEG strain at 90 days after the last dose resulted in high levels of protection with low parasite burden in the immunized animals. There were higher levels of specific IgG, IgA and IgM antibodies in the serum, and the i.p. immunized mice had higher levels of the high-affinity IgG and IgM antibodies than the orally immunized mice, which had more high-affinity IgA antibodies. B cells (CD19(+)), plasma cells (CD138(+)) and the CD4(+) and CD8(+) T cell populations were increased in both the blood and spleen. Cells from the spleen of the i.p. immunized mice also showed antigen-induced production of interleukin-10 (IL-10), interferon gamma (IFN-γ) and interleukin 4 (IL-4). The CD4(+) T cells, B cells and likely CD8(+) T cells from the spleens of the i.p. immunized mice proliferated with a specific antigen. The protection was correlated with the spleen and blood CD8(+) T cell, high-affinity IgG and IgM and antigen-induced IL-10 and IL-4 production. Immunization with irradiated T. gondii tachyzoites induces an immune response that is mediated by B cells and CD4(+) and CD8(+) T cells, with increased humoral and cellular immune responses that are necessary for host protection after infection. The vaccine is similar to natural infection, but free of tissue cysts; this immunity restrains infection at challenge and can be an attractive and efficient model for vaccine development in toxoplasmosis.


Assuntos
Sangue/imunologia , Imunidade Celular , Vacinas Protozoárias/imunologia , Baço/imunologia , Toxoplasma/imunologia , Administração Oral , Animais , Anticorpos Antiprotozoários/sangue , Linfócitos B/imunologia , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Imunidade Humoral , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Injeções Intraperitoneais , Masculino , Camundongos Endogâmicos BALB C , Vacinas Protozoárias/administração & dosagem , Subpopulações de Linfócitos T/imunologia , Toxoplasmose Animal/prevenção & controle , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
5.
J Nanosci Nanotechnol ; 16(5): 4762-70, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27483820

RESUMO

Gold nanoparticles (GNPs) are synthesized using the medicinal plant Leucas Aspera extract (LAE) and poly lactic acid-co-poly ethylene glycol-co-poly lactic acid (PLA-PEG-PLA) copolymer by water-in-oil (W/O) emulsion method. The proposed method of W/O emulsion technique involves synthesis of GNPs and loading of Leucas Aspera extract on to the PLA-PEG-PLA copolymer matrix simultaneously. The synthesized GNPs are characterized by Fourier transform infra-red (FTIR) spectroscopy, dynamic light scattering (DLS), X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The GNPs-LAE loaded polymer NPs are examined for the in vitro cytotoxicity on South African green monkey's kidney cells. The GNPs-LAE loaded polymer nanoconjugates exhibit maximum up to 95% of cell viability with 100 µg concentration of GNPs in the sample. The GNPs-LAE loaded polymer NPs exhibit better anti-inflammatory activity when compared to the pure LAE.


Assuntos
Sangue/imunologia , Medicamentos de Ervas Chinesas/química , Ouro/toxicidade , Lactatos/química , Nanopartículas Metálicas/toxicidade , Nanoconjugados/toxicidade , Polietilenoglicóis/química , Absorção Fisico-Química , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/síntese química , Sangue/efeitos dos fármacos , Chlorocebus aethiops , Difusão , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/toxicidade , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Nanocápsulas , Nanoconjugados/administração & dosagem , Nanoconjugados/química , Tensoativos/química , Células Vero
6.
Vet Pathol ; 53(5): 1095-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26574559

RESUMO

Semenogelins are proteins originating in the seminal vesicle and are useful markers for the presumptive identification of human semen. Detection of semenogelin can be done with a commercially available membrane test. In this study, a commercially available membrane test for human semenogelin proteins was used to assess for cross-reactivity in dog bodily fluids to allow for the potential utilization for detection of human semen in dog bodily fluids. The authors analyzed canine semen and other bodily fluids, including urine, saliva, vaginal secretions, fecal material, and blood. They also examined the distribution of human semenogelin I transcripts in the canine testis, prostate, and several bodily fluids by reverse transcription polymerase chain reaction. No cross-reactivity was observed in the canine bodily fluids tested except for a single rectal swab, which was negative on a second test. Further testing should be done to validate the use of this kit for screening samples from dogs suspected to have been victims of sexual abuse.


Assuntos
Bem-Estar do Animal , Fitas Reagentes , Sêmen/imunologia , Proteínas Secretadas pela Vesícula Seminal/imunologia , Animais , Sangue/imunologia , Secreções Corporais/imunologia , Reações Cruzadas/imunologia , Cães , Fezes , Feminino , Humanos , Masculino , Transtornos Parafílicos/diagnóstico , Saliva/imunologia , Urina , Vagina/metabolismo
7.
Eur J Clin Microbiol Infect Dis ; 31(6): 1271-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22120419

RESUMO

We have identified impaired neutrophils in elderly individuals which could be involved with Candida-related denture stomatitis (DS), an oral infection predominantly caused by Candida albicans, affecting especially elderly individuals using dental prosthesis. However, specific mechanisms performed by neutrophil contributing to the susceptibility of the elderly to DS are not fully understood. This study evaluated activation features of blood neutrophils from elderly and young individuals with DS. Blood neutrophils cultured with C. albicans from elderly subjects secreted decreased levels of CXCL8. However, C. albicans challenged-neutrophils from DS patients produced high IL-4 and IL-10, and low GM-CSF levels, regardless of age. Additional elastase activity of neutrophils from both elderly groups was detected after incubation with C. albicans, but only neutrophils from elderly DS demonstrated high myeloperoxidase activity. Therefore, DS patients have affected neutrophils, and the advance of age intensifies these damages. In summary, individuals with Candida-related denture stomatitis presented variation in the neutrophil phenotype and activation. Such alterations were more intense in neutrophils from infected elderly individuals.


Assuntos
Sangue/imunologia , Candida albicans/imunologia , Candidíase Bucal/imunologia , Ativação de Neutrófilo , Estomatite sob Prótese/imunologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Candida albicans/patogenicidade , Células Cultivadas , Citocinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/metabolismo , Peroxidase/metabolismo
8.
Malar J ; 10: 104, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21527045

RESUMO

BACKGROUND: Antibody responses to malaria antigens reflect exposure to parasites, and seroprevalence correlates with malaria transmission intensity. Antibodies are routinely measured in sera or on dried blood spots but a non-invasive method would provide extra utility in sampling general populations. Saliva is already in use in the detection of plasma-derived IgM and IgG to viral infections. In this study, antibodies to Plasmodium falciparum merozoite antigens were compared between blood and saliva samples from the same individuals in unlinked surveys conducted in Tanzania and The Gambia. METHODS: In Tanzania, 53 individuals provided paired fingerprick blood and saliva sample using two commercially available sampling devices. In the Gambia, archived plasma and saliva samples collected from 200 children in the Farafenni area in a cross-sectional survey were analyzed.IgG antibodies against P. falciparum antigens, Merozoite Surface Protein-1 (MSP-119) and Apical membrane Antigen (AMA-1) were measured by ELISA in paired saliva and blood samples from both sites. Antibody levels were compared as continuous optical density (OD) values and by sero-positivity. RESULTS: Significant correlations between saliva and plasma antibody levels were seen in Tanzania for both antigens, AMA-1(r2 range 0.93 to 0.89, p < 0.001) and MSP-119 (r2 range 0.93 to 0.75, p < 0.001), with a weaker correlation for results from The Gambia (r2range 0.64 to 0.63, p < 0.01). When assessed as seropositivity and compared with plasma, sensitivity and specificity were good with saliva antibody levels to both AMA-1 and MSP-1(19) (sensitivity range 64-77% and specificity range 91-100% & 47-67% and 90-97% respectively) over the different sample sets. CONCLUSIONS: These data demonstrate anti-malarial antibodies can be detected in saliva and correlate strongly with levels in plasma. This non-invasive relatively simple collection method will be potentially useful for general population surveys, and particularly in migratory populations or those with infrequent contact with health services or opposed to blood withdrawal. Further studies will be needed to optimize collection methods, standardize volumes and content and develop controls.


Assuntos
Anticorpos Antiprotozoários/análise , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Plasmodium falciparum/imunologia , Saliva/imunologia , Adolescente , Antígenos de Protozoários , Sangue/imunologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Gâmbia , Humanos , Imunoglobulina G/análise , Lactente , Proteínas de Membrana , Proteína 1 de Superfície de Merozoito , Plasma/imunologia , Proteínas de Protozoários , Estudos Soroepidemiológicos , Tanzânia
9.
Cells ; 10(11)2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34831361

RESUMO

Vascular grafts (VG) are medical devices intended to replace the function of a diseased vessel. Current approaches use non-biodegradable materials that struggle to maintain patency under complex hemodynamic conditions. Even with the current advances in tissue engineering and regenerative medicine with the tissue engineered vascular grafts (TEVGs), the cellular response is not yet close to mimicking the biological function of native vessels, and the understanding of the interactions between cells from the blood and the vascular wall with the material in operative conditions is much needed. These interactions change over time after the implantation of the graft. Here we aim to analyze the current knowledge in bio-molecular interactions between blood components, cells and materials that lead either to an early failure or to the stabilization of the vascular graft before the wall regeneration begins.


Assuntos
Prótese Vascular , Sangue/imunologia , Imunidade , Animais , Materiais Biocompatíveis/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Humanos , Falha de Tratamento
10.
J Clin Microbiol ; 48(3): 908-14, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20042630

RESUMO

Sodium polyanethole sulfonate (SPS; trade name, Liquoid) is a constituent in culture media used to grow bacteria from blood samples from patients suspected of bacteremia. SPS prevents the killing of bacteria by innate cellular and humoral factors. We analyzed the effect of SPS on the three complement activation pathways: the classical, alternative, and lectin pathways, respectively. Inhibition of complement activity by SPS is caused by a blocking of complement activation and is not a result of complement consumption. The classical pathway is inhibited at SPS concentrations greater than 0.1 mg/ml, and complete inhibition is seen at 0.4 mg/ml. An SPS concentration of 0.5 mg/ml completely inhibits the binding of C1q and subsequent incorporation of C3, C4, and C9. The same was observed for the alternative pathway with an inhibition at SPS concentrations from 0.1 mg/ml and a complete inhibition from 0.4 mg/ml. Here, properdin binding was completely absent, and no incorporation of C3 and C9 was observed. In contrast, the lectin complement pathway remains unaffected at these SPS concentrations, and inhibition is first observed from 0.7 mg/ml. A complete inhibition required concentrations greater than 1 mg/ml. SPS is used in growth media (e.g., BACTEC and BacT/Alert) at concentrations from 0.3 to 0.5 mg/ml. The well-known finding that certain bacteria are growth inhibited by blood factors could therefore be a consequence of the lectin pathway, which is not inhibited at these concentrations. In addition, our findings also open up the possibility of a new assay for the assessment of the functional capacity of the lectin complement pathway.


Assuntos
Técnicas Bacteriológicas/métodos , Sangue/imunologia , Ativação do Complemento/efeitos dos fármacos , Proteínas do Sistema Complemento/imunologia , Meios de Cultura/química , Fatores Imunológicos/farmacologia , Polianetolsulfonato/farmacologia , Bactérias/isolamento & purificação , Sangue/microbiologia , Humanos
11.
J Sci Food Agric ; 90(1): 168-74, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20355027

RESUMO

BACKGROUND: Tea (Camellia sinensis L.) is consumed all over the world and in especially large quantities in Japan and China, where it has been used not only as a daily beverage but also for medicinal purposes for thousands of years. Tea has been found to exhibit various bioregulatory activities, including antiallergic, anticarcinogenic, antimetastatic, antioxidative, antihypertensive, antihypercholesterolemic, anti-dental caries and antibacterial effects, and to influence intestinal flora. RESULTS: Cha Chuukanbohon Nou 6 is a tea cultivar improved by the National Institute of Vegetable and Tea Science (NIVTS) in Japan. On comparing chemical constituents of 11 varieties of tea leaves by high-performance liquid chromatography, we found two new major compounds in Cha Chuukanbohon Nou 6. Nuclear magnetic resonance spectroscopy revealed these compounds to be theogallin and 1,2-di-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-beta-D-glucopyranose. The two were similar in chemical structure to strictinin, an inhibitor of immunoglobulin (Ig) production. Thus their effects on the production of Igs by peripheral blood lymphocytes were tested. Both compounds, like strictinin, inhibited IgE production. CONCLUSION: The results suggest Cha Chuukanbohon Nou 6 to be the basis of an antiallergic beverage.


Assuntos
Camellia sinensis/química , Ácido Gálico/análogos & derivados , Taninos Hidrolisáveis/isolamento & purificação , Imunoglobulina E/biossíntese , Imunossupressores/isolamento & purificação , Linfócitos/efeitos dos fármacos , Extratos Vegetais/química , Ácido Quínico/análogos & derivados , Formação de Anticorpos/efeitos dos fármacos , Sangue/imunologia , Camellia sinensis/genética , Cromatografia Líquida de Alta Pressão , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Ácido Gálico/farmacologia , Genótipo , Humanos , Taninos Hidrolisáveis/química , Taninos Hidrolisáveis/farmacologia , Imunossupressores/química , Imunossupressores/farmacologia , Linfócitos/metabolismo , Estrutura Molecular , Fenóis/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Folhas de Planta/genética , Ácido Quínico/química , Ácido Quínico/isolamento & purificação , Ácido Quínico/farmacologia , Chá/química
12.
Diagn Microbiol Infect Dis ; 97(3): 115038, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32444155

RESUMO

Salivary antibodies are useful in surveillance and vaccination studies. However, low antibody levels and degradation by endonucleases are problematic. Oral flocked swabs are a potential non-invasive alternative for detecting viral antibodies. Seroprevalence for Cytomegalovirus (CMV), Varicella-Zoster virus (VZV), Epstein-Barr virus (EBV), Measles and Mumps IgG antibodies were determined from 50 matched serum, saliva and swabs samples from healthy volunteers using commercial ELISAs. CMV IgG, VZV IgG, and EBV EBNA-1 IgG, VCA IgG, and Measles IgG swab versus serum sensitivities were 95.8%, 96.0%, 92.1%, 95.5%, 84.5%, respectively, and swabs correlated well with saliva. Sensitivity of Mumps IgG in swabs and saliva was poor at 60.5%, and 68.2%, respectively. Specificities for IgG antibodies were 100% for CMV, EBV and Mumps, but could not be determined for VZV and Measles due to exclusively seropositive volunteers. Except for Mumps IgG, swabs correlate well with serum, are easy to self-collect and are stable at room temperature.


Assuntos
Anticorpos Antivirais/análise , Imunoglobulina G/análise , Mucosa Bucal/imunologia , Vírus/isolamento & purificação , Adulto , Sangue/imunologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Saliva/imunologia , Manejo de Espécimes , Vírus/imunologia
13.
BMC Microbiol ; 8: 206, 2008 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-19038023

RESUMO

BACKGROUND: Aggregatibacter actinomycetemcomitans is an oral bacterium associated with aggressive forms of periodontitis. Increasing evidence points to a link between periodontitis and cardiovascular diseases, however, the underlying mechanisms are poorly understood. This study investigated the pathogenic potential of free-soluble surface material, released from live planktonic and biofilm A. actinomycetemcomitans cells. RESULTS: By employing an ex vivo insert model (filter pore size 20 nm) we demonstrated that the A. actinomycetemcomitans strain D7S and its derivatives, in both planktonic and in biofilm life-form, released free-soluble surface material independent of outer membrane vesicles. This material clearly enhanced the production of several proinflammatory cytokines (IL-1 beta, TNF-alpha, IL-6, IL-8, MIP-1 beta) in human whole blood, as evidenced by using a cytokine antibody array and dissociation-enhanced-lanthanide-fluorescent-immunoassay. In agreement with this, quantitative real-time PCR indicated a concomitant increase in transcription of each of these cytokine genes. Experiments in which the LPS activity was blocked with polymyxin B showed that the stimulatory effect was only partly LPS-dependent, suggesting the involvement of additional free-soluble factors. Consistent with this, MALDI-TOF-MS and immunoblotting revealed release of GroEL-like protein in free-soluble form. Conversely, the immunomodulatory toxins, cytolethal distending toxin and leukotoxin, and peptidoglycan-associated lipoprotein, appeared to be less important, as evidenced by studying strain D7S cdt/ltx double, and pal single mutants. In addition to A. actinomycetemcomitans a non-oral species, Escherichia coli strain IHE3034, tested in the same ex vivo model also released free-soluble surface material with proinflammatory activity. CONCLUSION: A. actinomycetemcomitans, grown in biofilm and planktonic form, releases free-soluble surface material independent of outer membrane vesicles, which induces proinflammatory responses in human whole blood. Our findings therefore suggest that release of surface components from live bacterial cells could constitute a mechanism for systemic stimulation and be of particular importance in chronic localized infections, such as periodontitis.


Assuntos
Aggregatibacter actinomycetemcomitans/imunologia , Toxinas Bacterianas/imunologia , Biofilmes , Sangue/imunologia , Chaperonina 60/imunologia , Lipopolissacarídeos/imunologia , Periodontite/imunologia , Aggregatibacter actinomycetemcomitans/genética , Aggregatibacter actinomycetemcomitans/metabolismo , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/farmacologia , Sangue/efeitos dos fármacos , Chaperonina 60/metabolismo , Chaperonina 60/farmacologia , Citocinas/sangue , Citocinas/genética , Citocinas/imunologia , Expressão Gênica , Humanos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/imunologia , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Periodontite/microbiologia , Transporte Proteico
14.
J Clin Virol ; 43(3): 287-91, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18783984

RESUMO

BACKGROUND: Numerous immunological approaches exist to diagnose dengue or detect dengue virus (DENV) infections. OBJECTIVES: To determine the best immunological markers and specimen types for dengue diagnosis and for measuring incidence of DENV infection in community-based studies. STUDY DESIGN: In one study, acute- and convalescent-phase samples were collected from hospitalized suspected pediatric dengue cases in Managua, Nicaragua, from September 2003 to February 2004. A second study examined specimens collected in a community setting in Managua before and after the 2003-2004 dengue season to measure incidence of DENV infection. In both studies, detection of anti-DENV IgM, IgA, and IgG in serum, filter-paper blood spots, and saliva was compared to a gold standard performed on serum samples. RESULTS: For dengue diagnosis, the highest sensitivity and specificity was obtained by measuring IgM or IgA in serum or filter-paper blood spots; intermediate and poor results were obtained in saliva for IgM and IgA, respectively. Detection of IgG alone in serum, filter-paper blood spots, or saliva functioned best for measuring DENV infection. CONCLUSIONS: Detection of IgM and IgA in serum and filter-paper blood spots yielded optimal results for diagnosis of dengue cases, whereas IgG was the best marker for measuring incidence of DENV infection.


Assuntos
Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Sangue/imunologia , Dengue/diagnóstico , Saliva/imunologia , Soro/imunologia , Adolescente , Criança , Pré-Escolar , Dengue/epidemiologia , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina A/sangue , Imunoglobulina G/análise , Imunoglobulina G/sangue , Imunoglobulina M/análise , Imunoglobulina M/sangue , Lactente , Masculino , Nicarágua/epidemiologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Testes Sorológicos
15.
Colloids Surf B Biointerfaces ; 67(1): 41-5, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18786815

RESUMO

A novel O-butyryl chitosan (OBCS)-grafted polypyrrole (PPy) film was described. The immobilization was accomplished by photocrosslinking the OBCS onto PPy films under ultraviolet light irradiation. The surfaces of OBCS-grafted PPy film were characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and electron spectroscopy for chemical analysis (ESCA). The blood compatibility of the OBCS-grafted PPy film was evaluated by platelet-rich plasma (PRP) contacting experiments and protein adsorption experiments in vitro. These results have demonstrated that the surface with immobilized OBCS shows much less platelet adhesive and fibrinogen adsorption compared to the control surface. The bulk conductivity values of PPy films were measured by a modified four-probe method. The composite films have both good blood compatibility and high electrical conductivity that make them suitable for using as potential biomaterials, such as electrically conducting blood vessel and functionally haemocompatible substrate of biosensor used directly in whole blood.


Assuntos
Materiais Biocompatíveis , Sangue/imunologia , Condutividade Elétrica , Histocompatibilidade/imunologia , Polímeros , Pirróis , Materiais Biocompatíveis/química , Quitosana/química , Humanos , Polímeros/química , Pirróis/química , Espectroscopia de Infravermelho com Transformada de Fourier
16.
JDR Clin Trans Res ; 3(1): 65-75, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-30938653

RESUMO

Polymorphonuclear neutrophils (PMNs) are the primary leukocytes present in the healthy and inflamed oral cavity. While unique PMN activation states have been shown to differentiate health and periodontitis, little is known about the changes in PMN activation states that occur during the transition from periodontal health to gingivitis. The objective of this study was to characterize oral and circulatory PMNs during induction and resolution of experimental gingivitis. Healthy volunteers were recruited to undergo experimental gingivitis. Clinical assessment of pocket depths, bleeding on probing, gingival index, and plaque index, as well as flow cytometric analysis of CD (cluster of differentiation) activation markers on blood and oral PMNs, was performed weekly. All clinical parameters increased significantly during the induction period and returned to baseline levels during the resolution phase. During the induction phase, while oral PMN counts increased, oral PMN activation state based on surface expression of CD63, CD11b, CD16, and CD14 was diminished compared to those seen in health and during the resolution phase. PMNs in circulation during onset showed increased activation based on CD55, CD63, CD11b, and CD66a. Using clinical parameters and oral PMN counts assessed at day 21, we noted 2 unique disease patterns where one-third of subjects displayed an exaggerated influx of oral PMNs with severe inflammation compared to the majority of the population who experienced a moderate level of inflammation and PMN influx. This supports the notion that PMN influx and severe inflammatory changes during gingivitis could identify subjects at risk for the development of severe gingival inflammation and progression toward destructive periodontitis. This study demonstrates that oral PMN activation states are reduced in gingivitis and suggest that only in periodontitis do PMNs become hyperactivated and tissue damaging. Knowledge Transfer Statement: Our article creates a paradigm for future studies of the evolution of essential oral and circulatory biomarkers to identify individuals at risk to develop periodontitis at an early stage of periodontal disease, which is reversible upon proper oral hygiene practices and dental treatments.


Assuntos
Gengivite/imunologia , Boca/imunologia , Ativação de Neutrófilo , Neutrófilos/fisiologia , Adolescente , Adulto , Biofilmes , Biomarcadores , Sangue/imunologia , Índice de Placa Dentária , Feminino , Citometria de Fluxo , Bolsa Gengival , Voluntários Saudáveis , Humanos , Contagem de Leucócitos , Masculino , Modelos Biológicos , Índice Periodontal , Adulto Jovem
17.
J Clin Virol ; 102: 77-83, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29525634

RESUMO

BACKGROUND: A reliable population screening strategy for hepatitis C virus (HCV) infection may be based in easy-to-use point-of-care (POC) tests for HCV antibodies, but validation data is needed before their potential widespread use in primary care or outreach practice. Besides, the sensitivity of these POC tests in patients with spontaneous or treatment-induced viral clearance is unknown. OBJECTIVES: To test the performance of a non-invasive POC anti-HCV test (OraQuick HCV rapid test) in oral mucosal transudate (OMT) and fingerstick blood from patients with known anti-HCV serostatus and with or without active viremia (after treatment-induced clearance). STUDY DESIGN: A risk factor questionnaire was collected from 317 consecutive patients (anti-HCV positive/HCV-RNA positive n = 107; anti-HCV positive/HCV-RNA negative after antiviral treatment n = 107; anti-HCV negative with other liver diseases n = 109) before performing the OraQuick HCV rapid test in OMT (n = 317) and fingerstick blood (n = 251). We calculated the sensitivity and specificity of the test by using anti-HCV serostatus as the reference gold-standard. RESULTS: Among all anti-HCV seropositive patients, the clinical sensitivity and specificity of the OraQuick HCV rapid test in OMT was 89.9% and 100%, respectively. In fingerstick blood, the sensitivity improved to 98.8%. The sensitivity was higher in OMT (97.2%) in anti-HCV seropositive patients who were viremic as compared to that in non-viremic individuals (82.2%). In contrast, there were no significant differences in sensitivity between viremic and non-viremic individuals when testing fingerstick blood. Finally, extension of the read time to 40 min enhanced the sensitivity, especially in OMT (up to 94.7%) and in the subgroup of non-viremic, anti-HCV-positive patients (up to 90.1%). CONCLUSIONS: The OraQuick HCV rapid test in OMT has a high sensitivity and specificity for detecting active HCV infection that decreases substantially in anti-HCV positive/HCV-RNA negative patients with treatment-induced viral clearance. For these individuals, extension of read times and testing fingerstick blood showed improved sensitivity.


Assuntos
Sangue/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/análise , Hepatite C/diagnóstico , Imunoensaio/normas , Saliva/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/uso terapêutico , Testes Diagnósticos de Rotina/normas , Feminino , Hepacivirus/isolamento & purificação , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
18.
J Virol Methods ; 133(1): 1-5, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16360219

RESUMO

Hepatitis C (HCV) is common in developing countries, where blood sampling and expensive sophisticated methods for detection are less available. Hemodialysis patients have high prevalence of HCV and may resemble sick populations in developing countries in relation to immunosuppression and antibodies production. For these reasons anti-HCV antibodies were assayed in saliva of hemodialysis patients by ImmunoComb II assay that is less laborious, relatively inexpensive and easy to perform If the findings are confirmed by larger studies this method may be useful especially in developing countries. Serum and saliva samples were obtained from 37 hemodialysis patients and assayed by ImmunoComb II kit. In positive PCR patients the saliva test had 100% sensitivity, which was as good as serum anti-HCV Axsym testing. Saliva testing had a similar or better specificity than the serum method.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/análise , Hepatite C/epidemiologia , Imunoensaio/métodos , RNA Viral/análise , Saliva/imunologia , Idoso , Sangue/imunologia , Feminino , Hepatite C/diagnóstico , Hepatite C/imunologia , Humanos , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , RNA Viral/genética , Kit de Reagentes para Diagnóstico , Diálise Renal/efeitos adversos , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
19.
Biomaterials ; 104: 258-68, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27472163

RESUMO

Endothelial cell activation resulting from biomaterial contact or biomaterial-induced blood activation may in turn also affect hemostasis and inflammatory processes in the blood. Current in vitro hemocompatibility assays typically ignore these modulating effects of the endothelium. This study describes a co-incubation system of human whole blood, biomaterial and endothelial cells (ECs) that was developed to overcome this limitation. First, human endothelial cells were characterized in terms of their expression of coagulation- and inflammation-relevant markers in response to various activators. Subsequently, their capacity to regulate hemostasis as well as complement and granulocyte activation was monitored in a hemocompatibility assay. After blood contact, quiescent ECs exhibited anticoagulant and anti-inflammatory properties. When they were co-incubated with surfaces exhibiting pro-coagulant or pro-inflammatory characteristics, the ECs down-regulated coagulation but not complement or leukocyte activation. Analysis of intracellular levels of the endothelial activation markers E-selectin and tissue factor showed that co-incubation with model surfaces and blood significantly increased the activation state of ECs. Finally, the coagulation- and inflammation-modulating properties of the ECs were tested after blood/biomaterial exposure. Pre-activation of ECs by biomaterials in the blood induced a pro-coagulant and pro-inflammatory state of the ECs, wherein the pro-coagulant response was higher for biomaterial/blood pre-activated ECs than for TNF-α-pre-activated cells. This work provides evidence that biomaterials, even without directly contacting the endothelium, affect the endothelial activation state with and have consequences for plasmatic and cellular reactions in the blood.


Assuntos
Materiais Biocompatíveis/química , Sangue/imunologia , Técnicas de Cocultura/métodos , Citocinas/imunologia , Células Endoteliais/imunologia , Mediadores da Inflamação/imunologia , Células Cultivadas , Humanos , Teste de Materiais
20.
Trop Biomed ; 32(2): 247-56, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26691253

RESUMO

Visceral leishmaniasis (VL) is a tropical neglected disease endemic in 98 countries and affects more than 58 000 individuals per year. Several serological tests are available for VL diagnosis, including an immunochromatographic (IC) test with the rK39 antigen and finger prick-collected blood, a rapid and low-invasive test. Here, we investigate the possibility to use saliva as a non-invasive source of biological material for the rK39 IC test. Blood samples from 84 patients with suspected VL were screened by the rK39 IC test, and 29 were confirmed as being infected by a positive rK39 IC test and the presence of amastigotes on smears slides or parasite DNA (detected using PCR-RFLP) from bone marrow aspirate. The rK39 IC test using saliva samples was positive for 17 of the 29 confirmed VL cases (58.6%). The amount of Leishmania-specific IgG or total IgG, as evaluated by an immunoenzymatic assay, was higher in the saliva of patients who had rK39 IC test positivity using saliva, whereas the amount of Leishmania-specific IgA or total IgA was similar to the healthy donors. These results suggest that saliva is not an appropriated material for diagnosing VL with this test.


Assuntos
Anticorpos Antiprotozoários/análise , Antígenos de Protozoários/imunologia , Cromatografia de Afinidade/métodos , Leishmania/imunologia , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/imunologia , Saliva/imunologia , Adolescente , Adulto , Idoso , Sangue/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
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