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1.
Molecules ; 26(3)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513993

RESUMO

Amikacin (Amk) analysis and quantitation, for pharmacokinetics studies and other types of investigations, is conventionally performed after extraction from plasma. No report exists so far regarding drug extraction from whole blood (WB). This can represent an issue since quantification in plasma does not account for drug partitioning to the blood cell compartment, significantly underrating the drug fraction reaching the blood circulation. In the present work, the optimization of an extraction method of Amk from murine WB has been described. The extraction yield was measured by RP-HPLC-UV after derivatization with 1-fluoro-2,4-dinitrobenzene, which produced an appreciably stable derivative with a favorable UV/vis absorption. Several extraction conditions were tested: spiked Amk disulfate solution/acetonitrile/WB ratio; presence of organic acids and/or ammonium hydroxide and/or ammonium acetate in the extraction mixture; re-dissolution of the supernatant in water after a drying process under vacuum; treatment of the supernatant with a solution of inorganic salts. The use of 5% (by volume) of ammonium hydroxide in a hydro-organic solution with acetonitrile, allowed the almost quantitative (95%) extraction of the drug from WB.


Assuntos
Amicacina/química , Sangue/metabolismo , Plasma/química , Acetonitrilas/química , Hidróxido de Amônia/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Feminino , Camundongos
2.
J Infect Dis ; 220(10): 1645-1654, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31300818

RESUMO

BACKGROUND: Vaginal candidiasis is common disease affecting women; however, how Candida albicans shift from commensalism towards a pathogenic status remains poorly understood. The present study investigated the vaginal epithelial cell (EC) response dynamics under various conditions. METHODS: Healthy women, asymptomatic C. albicans carriers, and symptomatic patients with vaginal candidiasis were enrolled in this study. ECs in vaginal swabs were analyzed with cytofluorimetric analysis for pattern recognition receptors and intracellular signals, with lactate dehydrogenase assay performed for cell damage, and an enzyme-linked immunosorbent assay for cytokine expression. RESULTS: The level of toll-like receptor 4 (TLR4), TLR2, and erythropoietin-producing hepatoma A2 (EphA2) expression was significantly higher in ECs from asymptomatic and symptomatic subjects compared to healthy subjects. Activation of transcription factors, nuclear factor-κB (NF-κB) and c-Fos-p-38, was observed in ECs from symptomatic and asymptomatic pseudohyphae/hyphae carriers but not from the asymptomatic yeast carriers. EC damage was only observed in symptomatic patients. CONCLUSIONS: The presence of pseudohyphae/hyphae is required to determine vaginal candidiasis; however, it may be not sufficient to induce the pathologic process associated with neutrophil recruitment and EC damage. This study sheds light on the ambiguous role of the hyphal form during vaginal human commensalism.


Assuntos
Candida albicans/crescimento & desenvolvimento , Candidíase Vulvovaginal/patologia , Portador Sadio/imunologia , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Hifas/crescimento & desenvolvimento , Vagina/microbiologia , Adulto , Sobrevivência Celular , Células Epiteliais/fisiologia , Feminino , Humanos , Fatores Imunológicos/análise , Pessoa de Meia-Idade , Adulto Jovem
3.
Infect Immun ; 83(5): 1940-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25712931

RESUMO

We recently demonstrated that the secreted aspartyl proteinases (Saps), Sap2 and Sap6, of Candida albicans have the potential to induce the canonical activation of the NLRP3 inflammasome, leading to the secretion of interleukin-1ß (IL-1ß) and IL-18 via caspase-1 activation. We also observed that the activation of caspase-1 is partially independent from the NLRP3 activation pathway. In this study, we examined whether Sap2 and Sap6 are also able to activate the noncanonical inflammasome pathway in murine macrophages. Our data show that both Sap2 and Sap6 can activate caspase-11 through type I interferon (IFN) production. Caspase-11 cooperates to activate caspase-1, with a subsequent increase of IL-1ß secretion. Endocytosis and internalization of Saps are required for the induction of type I IFN production, which is essential for induction of noncanonical inflammasome activation. Our study indicates a sophisticated interplay between caspase-1 and caspase-11 that connects the canonical and noncanonical pathways of inflammasome activation in response to C. albicans Saps.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Candida albicans/enzimologia , Caspases/análise , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Patógeno , Inflamassomos/metabolismo , Inflamação/patologia , Animais , Caspase 1/metabolismo , Caspases Iniciadoras , Linhagem Celular , Endocitose , Feminino , Interferon Tipo I/metabolismo , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL
4.
Eur J Immunol ; 43(3): 679-92, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23280543

RESUMO

In a recent report, we demonstrated that distinct members of the secreted aspartic protease (Sap) family of Candida albicans are able to induce secretion of proinflammatory cytokines by human monocytes, independently of their proteolytic activity and specific pH optima. In particular, C. albicans Sap2 and Sap6 potently induced IL-1ß, TNF-α, and IL-6 production. Here, we demonstrate that Sap2 and Sap6 proteins trigger IL-1ß and IL-18 production through inflammasome activation. This occurs via NLRP3 and caspase-1 activation, which cleaves pro-IL-1ß into secreted bioactive IL-1ß, a cytokine that was induced by Saps in monocytes, in monocyte-derived macrophages and in dendritic cells. Downregulation of NLRP3 by RNA interference strongly reduced the secretion of bioactive IL-1ß. Inflammasome activation required Sap internalization via a clathrin-dependent mechanism, intracellular induction of K(+) efflux, and ROS production. Inflammasome activation of monocytes induced by Sap2 and Sap6 differed from that induced by LPS-ATP in several aspects. Our data reveal novel immunoregulatory mechanisms of C. albicans and suggest that Saps contribute to the pathogenesis of candidiasis by fostering rather than evading host immunity.


Assuntos
Ácido Aspártico Proteases/metabolismo , Candida albicans/enzimologia , Proteínas de Transporte/metabolismo , Inflamassomos/metabolismo , Candida albicans/imunologia , Células Cultivadas , Humanos , Inflamassomos/imunologia , Interleucina-18/biossíntese , Interleucina-1beta/biossíntese , Lisossomos/metabolismo , Modelos Biológicos , Monócitos/imunologia , Monócitos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Potássio/metabolismo , Transdução de Sinais , Superóxidos/metabolismo
5.
Mycopathologia ; 175(1-2): 1-11, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23054331

RESUMO

The animal models available for studying the immune response to genital tract infection require induction of a pseudo estrous state, usually achieved by administration of 17-ß-estradiol. In our experimental model of vaginal candidiasis, under pseudo estrus, different strains of mice were used. We observed major differences in the clearance of Candida albicans infection among the different strains, ascribable to differing susceptibility to estradiol treatment. In the early phase of infection CD1, BALB/c, C57BL/6 albino and C57BL/6 mice were colonized to similar levels, while in the late phase of infection, BALB/c mice, which are considered genetically resistant to C. albicans infection, exhibited greater susceptibility to vaginal candidiasis than CD1 and C57BL/6 albino strains of mice. This was because estradiol induced "per se" enlarged and fluid-filled uteri, more pronounced in infected mice and consistently more evident in BALB/c and C57BL/6 mice than in CD1 mice. Unlike CD1, BALB/c and C57BL/6 mice showed a heavy fungal colonization of the uterus, even though C57BL/6 mice apparently cleared C. albicans from the vagina. The presence of C. albicans in the vagina and uterus was accompanied by a heavy bacterial load. Collectively these observations prompted us to carry out a careful analysis of estradiol effects in a mouse model of vaginal infection.


Assuntos
Candida albicans/fisiologia , Candidíase Vulvovaginal/imunologia , Candidíase Vulvovaginal/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Estrogênios/metabolismo , Camundongos , Animais , Candidíase Vulvovaginal/genética , Feminino , Especificidade da Espécie
6.
J Immunol ; 183(1): 191-200, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19542430

RESUMO

Rheumatoid arthritis (RA) is a chronic and debilitating autoimmune disease characterized by chronic joint inflammation with subsequent cartilage and bone destruction. RA is emerging as a model of IL-17-driven autoimmune inflammatory disease. IL-17 is a marker for Th17 cells, with its master regulator being the retinoic acid receptor-related orphan receptor (RORgammat) regulated by STAT3 signaling. Glucuronoxylomannan (GXM), a polysaccharide representing the main component of the capsular material of the opportunistic yeast Cryptococcus neoformans, exhibits potent immunosuppressive properties both in vitro and in vivo. The present study investigates the effects of GXM treatment on the progression of collagen-induced arthritis. GXM suppressed clinical signs of collagen-induced arthritis and blocked joint erosion progression. This effect was mediated by down-regulation of key cytokines involved in the pathogenesis of RA such as TNF-alpha and IL-1beta, and up-regulation of the inhibitory cytokine IL-10. Moreover, a reduction of IL-6 and TGF-beta, which inhibit Th17 differentiation with consequent decreased IL-17 production at the local and systemic level, was observed. The effect of GXM on Th17 differentiation mirrored the reduction in STAT3 activation and inhibition of RORgammat synthesis. Consequently, this work highlights the beneficial properties of an efficacious compound that could eventually be destined to the clinic.


Assuntos
Artrite Reumatoide/imunologia , Cryptococcus neoformans/imunologia , Citocinas/biossíntese , Imunossupressores/administração & dosagem , Mediadores da Inflamação/metabolismo , Interleucina-17/fisiologia , Polissacarídeos/administração & dosagem , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Antígenos de Fungos/administração & dosagem , Antígenos de Fungos/imunologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/epidemiologia , Artrite Experimental/imunologia , Artrite Experimental/patologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Reabsorção Óssea/imunologia , Reabsorção Óssea/patologia , Colágeno Tipo II/toxicidade , Citocinas/antagonistas & inibidores , Citocinas/fisiologia , Imunossupressores/imunologia , Incidência , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/fisiologia , Interleucina-17/antagonistas & inibidores , Masculino , Camundongos , Camundongos Endogâmicos DBA , Osteoclastos/imunologia , Osteoclastos/patologia , Polissacarídeos/imunologia , Polissacarídeos/uso terapêutico , Ligante RANK/biossíntese , Ligante RANK/genética , Índice de Gravidade de Doença , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Auxiliares-Indutores/patologia
7.
Microorganisms ; 9(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34946178

RESUMO

Candida albicans is a commensal fungus of the vaginal mucosa and the principal etiological agent of vaginal candidiasis. Vaginal dysbiosis has been reported during vulvovaginal candidiasis (VVC), with a progressive decrease in Lactobacillus crispatus population and an increase in L. iners population. To date, the role of L. iners in VVC pathogenesis remains scarcely explored. Herein we investigated the in vitro effect of L. iners cell-free supernatant (CFS) on the ability of C. albicans to form biofilms. Biomass and metabolic activity were measured by crystal violet and XTT assays. Further, light microscopy was performed to determine the effect of L. iners CFS on biofilm cellular morphology. We found that L. iners CFS induced a significant increase in biofilm formation by C. albicans clinical isolates which were categorized as moderate or weak biofilm producers. This effect was associated with an enhancement of hyphal/pseudohyphal growth, and the expression levels of HWP1 and ECE1, which are typical hyphae-associated genes, were upregulated. Overall, these results suggest that L. iners contributes to the pathogenesis of VVC and highlight the complexity of the interaction between C. albicans and vaginal lactobacilli. Understanding these interactions could prove essential for the development of new strategies for treating VVC.

8.
Cells ; 10(9)2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34571877

RESUMO

Glucocorticoids are the most powerful anti-inflammatory and immunosuppressive pharmacological drugs available, despite their adverse effects. Glucocorticoid-induced leucine zipper (GILZ) is a glucocorticoid-induced gene that shares several anti-inflammatory properties with glucocorticoids. Although immunosuppressive effects of glucocorticoids on neutrophils remain poorly understood, we previously demonstrated that GILZ suppresses neutrophil activation under glucocorticoid treatment. Here, we sought to explore the regulation of Toll-like receptor 2 (TLR2) by the synthetic glucocorticoid dexamethasone (DEX) on neutrophils and the associated GILZ involvement. Peripheral blood neutrophils were isolated from wild type and GILZ-knock-out (KO) mice. TLR2 was found to be downregulated by the in vivo administration of glucocorticoids in wild type but not in GILZ-KO neutrophils, suggesting the involvement of GILZ in TLR2 downregulation. Accordingly, the TLR2-associated anti-fungal activity of neutrophils was reduced by DEX treatment in wild type but not GILZ-KO neutrophils. Furthermore, GILZ did not interact with NF-κB but was found to bind with STAT5, a pivotal factor in the regulation of TLR2 expression. A similar modulation of TLR2 expression, impaired phagocytosis, and killing activity was observed in circulating human neutrophils treated in vitro with DEX. These results demonstrate that glucocorticoids reduce the ability of neutrophils to respond to infections by downregulating TLR2 via GILZ, thereby reducing critical functions.


Assuntos
Dexametasona/farmacologia , Regulação para Baixo/efeitos dos fármacos , Neutrófilos/imunologia , Receptor 2 Toll-Like/metabolismo , Fatores de Transcrição/genética , Animais , Dexametasona/administração & dosagem , Glucocorticoides/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/citologia , Neutrófilos/metabolismo , Fator de Transcrição STAT5/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
Front Microbiol ; 11: 718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32373104

RESUMO

Vaginal infections affect 70% of women during their lifetimes and account for millions of annual doctors' visits. These infections are predominantly represented by vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV). Although standard antimicrobial agents remain the major strategy for the prevention and treatment of vaginal infections, both VVC and BV are difficult to treat due to high rates of resistance and recurrence, high probability of complications, and negative effects on the vaginal microbiota. This review focuses on a new approach of yeast-based probiotics for the prevention and/or treatment of these common vaginal infections.

10.
Front Microbiol ; 11: 2085, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983061

RESUMO

Staphylococcus aureus infections associated with implanted medical devices are difficult to treat and require long-lasting antibiotic therapies, especially when device removal is not possible or easy such as in the case of joint prostheses. Biofilm formation is a major cause of treatment failure and infection recurrence. This study aimed to test, for the first time, the in vitro combination of tedizolid plus rifampicin on methicillin-sensitive (MSSA ATCC 6538) and methicillin-resistant (MRSA ATCC 43300) S. aureus mature biofilm. Here, we demonstrated that the combination of tedizolid with rifampicin significantly disaggregated pre-formed biofilm of both strains, reduced their metabolic activity and exerted bactericidal activity at clinically meaningful concentrations. Notably, tedizolid was able to completely prevent the emergence of resistance to rifampicin. Moreover these effects were similar to those obtained with daptomycin plus rifampicin, a well-known and widely used combination. Preliminary results on some MRSA clinical isolates confirmed the efficacy of this combination in reducing biofilm biomass and preventing rifampicin resistance onset. Further in vivo studies are needed to confirm the validity of this promising therapeutic option that can be useful against biofilm-associated S. aureus infections.

11.
Sci Rep ; 10(1): 1978, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029862

RESUMO

Bacterial vaginosis (BV) is one of the most common vaginal infections among women of childbearing age. Gardnerella vaginalis (G. vaginalis) is a keystone microorganism present in more than 95% of all BV cases. The first step of the infection process in BV is mediated by interaction of microorganisms with epithelial cells (ECs). However, the role of these cells in BV pathogenesis is largely unknown. The present study aimed to investigate the vaginal EC response during BV. Twenty healthy women and 34 women with BV were enrolled in this study. The number of ECs in the vaginal swab was counted and analyzed for intracellular signals and apoptosis by flow cytometry. Cell damage was evaluated by lactate dehydrogenase assay. Compared to that in healthy donors, the percentage of exfoliated vaginal ECs was increased in women with BV, and an absence of neutrophils was observed in both groups. Activation signals, such as p-IκBα and c-Fos were unmodulated in the vaginal ECs of women with BV. Moreover, EC damage and apoptosis were significantly increased in patients with BV. Apoptosis was related to caspase-3 activation and the presence of G. vaginalis. This study provides the first evidence of a direct involvement of G. vaginalis in the apoptotic process of vaginal ECs during BV. This effect was mediated by caspase-3 activation, and G. vaginalis appeared to be one of causes for inducing EC apoptosis in BV. Hence, our findings suggest a possible explanation for the increased exfoliation of ECs in the vagina during BV.


Assuntos
Apoptose/imunologia , Células Epiteliais/patologia , Gardnerella vaginalis/imunologia , Vagina/patologia , Vaginose Bacteriana/imunologia , Adulto , Estudos de Casos e Controles , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Feminino , Gardnerella vaginalis/isolamento & purificação , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Vagina/citologia , Vagina/imunologia , Vagina/microbiologia , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/patologia , Adulto Jovem
12.
J Glob Antimicrob Resist ; 23: 4-8, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32810638

RESUMO

OBJECTIVES: The aim of this study was to report on in vitro tests of antibacterial activity of ceftazidime/avibactam in combination against planktonic or biofilm KPC carbapenemase-producing Klebsiella pneumoniae (KPC-Kp), the rate of KPC-Kp blood isolates in University of Perugia Hospital over a 5-year period, and their antimicrobial susceptibility patterns. METHODS: The antibacterial activity of ceftazidime/avibactam in combination with other antimicrobials was assessed against planktonic and biofilm bacteria by Etest and checkerboard assay. A retrospective review of laboratory data was performed to evaluate the rate of KPC-Kp from blood samples and their antimicrobial susceptibility patterns. RESULTS: Between 2014 and 2019, 130/4241 (3.1%) KPC-Kp were identified from blood cultures. Their rate increased from 2.3% in 2014-2015 to 4.5% over the last 3 years. Overall, 4.6% (6/130) of KPC-Kp isolates were susceptible to meropenem, 65.4% (85/130) to colistin, 65.1% (84/129) to tigecycline, 34.6% (45/130) to amikacin, 36.2% (42/116) to gentamicin, 40.2% (39/97) to fosfomycin and 91.5% (65/71) to ceftazidime/avibactam. Five of six ceftazidime/avibactam-resistant KPC-Kp were isolated from patients not treated with ceftazidime/avibactam. Synergism was detected both by Etest and checkerboard assay for the combination of ceftazidime/avibactam plus meropenem against planktonic isolates, whilst lower bactericidal activity was observed in biofilm KPC-Kp isolates. CONCLUSIONS: Our in vitro data suggest that the combination of ceftazidime/avibactam plus meropenem has a synergistic antibacterial activity against planktonic bacteria, whilst a lower activity was detected against biofilm, suggesting worse clinical outcomes whenever biofilm infections are present. Further analyses are required to confirm these results before extending them to clinical practice.


Assuntos
Anti-Infecciosos , Infecções por Klebsiella , Antibacterianos/farmacologia , Compostos Azabicíclicos , Proteínas de Bactérias , Biofilmes , Ceftazidima/farmacologia , Humanos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plâncton , Estudos Retrospectivos , beta-Lactamases
13.
Microorganisms ; 8(9)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847138

RESUMO

Bacterial vaginosis (BV) is characterized by the presence of a polymicrobial biofilm where Gardnerella vaginalis plays a key role. Previously, we demonstrated that Saccharomyces cerevisiae CNCM (French National Collection of Cultures of Microorganisms) I-3856 is helpful in resolving experimental simulated BV in mice. In this study, we analyzed its capacity to affect G. vaginalis biofilms and to potentiate the activity of standard antimicrobial agents. We also investigated the anti-biofilm activity of Lacticaseibacillus rhamnosus GG (ATCC 53103), a well-known strain for its intestinal healthy benefits. Biofilm biomass was assessed by crystal violet staining, and G. vaginalis viability was assessed by a colony forming unit (CFU) assay. Here, for the first time, we demonstrated that S. cerevisiae CNCM I-3856 as well as L. rhamnosus GG were able (i) to significantly inhibit G. vaginalis biofilm formation, (ii) to markedly reduce G. vaginalis viability among the biomass constituting the biofilm, (iii) to induce disaggregation of preformed biofilm, and (iv) to kill a consistent amount of bacterial cells in a G. vaginalis preformed biofilm. Furthermore, S. cerevisiae CNCM I-3856 strongly potentiates the metronidazole effect on G. vaginalis biofilm viability. These results suggest that S. cerevisiae CNCM I-3856 as well as L. rhamnosus GG could be potential novel therapeutic agents against bacterial vaginosis.

14.
J Leukoc Biol ; 83(5): 1286-94, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18252869

RESUMO

In this study, we analyzed the possibility that Indinavir (IDV), a well-known protease inhibitor (PI) used in highly active antiretroviral therapy, could affect immune response against the opportunistic fungus Cryptococcus neoformans. In particular, the quality of dendritic cell (DC) response was analyzed. The results reported here show that IDV treatment induces an expansion of DC with CD8alpha phenotype in spleens of infected hosts. Splenic CD11c+ DC expressed elevated costimulatory molecules such as CD40 and CD80, showed an increased expression of mRNA for proinflammatory cytokines, and secreted abundant IL-12. Integration of all aforementioned regulatory effects results in development of an efficient, T cell-protective response that reflects a consistent reduction in fungus colonization at a cerebral level. These results could help to elucidate the immunoregulatory activity of PI and point out the beneficial effects of IDV in regulating DC functions and antifungal activity. Therefore, although new PI are being introduced in the clinical setting, nevertheless, given its low cost and proven efficacy, IDV could still be considered a potential key compound in the treatment of HIV in resource-limited settings.


Assuntos
Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Cryptococcus neoformans/efeitos dos fármacos , Células Dendríticas/imunologia , Inibidores da Protease de HIV/farmacologia , Indinavir/farmacologia , Animais , Antifúngicos/uso terapêutico , Antígeno B7-1/biossíntese , Antígeno B7-1/efeitos dos fármacos , Antígenos CD40/biossíntese , Antígenos CD40/efeitos dos fármacos , Antígenos CD8/análise , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/microbiologia , Feminino , Citometria de Fluxo , Indinavir/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C
15.
Front Microbiol ; 10: 2669, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803172

RESUMO

In acute vulvovaginal candidiasis (VVC), the fungus Candida albicans activates inflammasome receptors of vaginal epithelial cells through the production of virulence and immuno-inflammatory factors. Here, we show that in VVC patients, genes encoding some of the above factors (SAP2, SAP5, SAP6, ECE1, and HWP1) are expressed in a correlated fashion. Cytological observations pointed out that pseudohyphal filaments with yeast cells are dominant at the acidic vaginal pH, and this is coupled with co-expression, at roughly similar level, of SAP2, a typical yeast and ECE1, a typical hyphae-associated genes. In contrast, vigorous hyphal growth dominated at the neutral vaginal pH of mice experimentally infected with C. albicans isolates from VVC subjects, and this is coupled with a high ratio of ECE1 to SAP2 expression. We suggest that the pseudohyphal rather than true hyphal cells of C. albicans play a critical role in VVC, possibly through the activity of multiple inflammasome inducers.

16.
Front Microbiol ; 10: 1469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354640

RESUMO

Oropharyngeal candidiasis is a common opportunistic mucosal infection of the oral cavity, mainly caused by an overgrowth of Candida albicans. This infection can inhibit nutritional intakes and strongly affect quality of life. To date, standard therapeutic strategies involving the administration of antifungal drugs can bring several side effects, not least the emergence of drug-resistant strains. The purpose of this study is to investigate the effectiveness of Saccharomyces cerevisiae CNCM I-3856 (live or inactivated cells) against oropharyngeal candidiasis. Our results show that administration of S. cerevisiae CNCM I-3856 (live or inactivated cells) in the oral cavity of C57BL/6J mice resulted in a protective effect against oropharyngeal candidiasis. The strongest effect was obtained with live S. cerevisiae CNCM I-3856. This was related to: (1) a decrease in C. albicans load in the oral cavity, esophagus, stomach, and duodenum; (2) an early resolution of inflammatory process in the tongue; (3) a marked reduction in C. albicans virulence factors; and (4) a consistent increase in neutrophil antimicrobial capacity. These findings suggest that S. cerevisiae products are potentially beneficial in the treatment of oropharyngeal candidiasis.

17.
Infect Immun ; 76(9): 4359-67, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18591233

RESUMO

Mannoproteins are cell wall components of pathogenic fungi and play major virulence and immunogenic roles with both their mannan and protein moieties. The 65-kDa mannoprotein (MP65) of Candida albicans is a beta-glucanase adhesin recognized as a major target of the human immune response against this fungus, and its recombinant product (rMP65; devoid of the mannan moiety) is presently under consideration as a vaccine candidate. Here we investigated cellular and molecular aspects of the interaction of rMP65 with human antigen-presenting cells. We also assessed the ability of rMP65 to initiate a T-cell response. Both the native mannosylated MP65 (nMP65) and the recombinant product were efficiently bound and taken up by macrophages and dendritic cells. However, contrarily to nMP65, rMP65 did not induce tumor necrosis factor alpha and interleukin-6 release from these cells. On the other hand, rMP65 was rapidly endocytosed by both macrophages and dendritic cells, in a process involving both clathrin-dependent and clathrin-independent mechanisms. Moreover, the RGD sequence inhibited rMP65 uptake to some extent. After internalization, rMP65 partially colocalized with lysosomal membrane-associated glycoproteins 1 and 2. This possibly resulted in efficient protein degradation and presentation to CD4(+) T cells, which proliferated and produced gamma interferon. Collectively, these results demonstrate that the absence of the mannan moiety does not deprive MP65 of the capacity to initiate the pattern of cellular and molecular events leading to antigen presentation and T-cell activation, which are essential features for further consideration of MP65 as a potential vaccine candidate.


Assuntos
Candida albicans/imunologia , Células Dendríticas/imunologia , Ativação Linfocitária , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes/imunologia , Linfócitos T/imunologia , Proliferação de Células , Células Cultivadas , Citocinas/biossíntese , Humanos , Lisossomos/química , Macrófagos/imunologia , Mananas/metabolismo , Glicoproteínas de Membrana/química , Proteínas Recombinantes/química
18.
PLoS One ; 13(7): e0201436, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30063729

RESUMO

Vaginal candidiasis is a common disorder in women of childbearing age, caused primarily by the dimorphic fungus Candida albicans. Since C. albicans is a normal commensal of the vaginal mucosa, a long-standing question is how the fungus switches from being a harmless commensal to a virulent pathogen. Work with human subjects and in mouse disease models suggests that host inflammatory processes drive the onset of symptomatic infection. Fungal cell wall molecules can induce inflammation through activation of epithelial and immune receptors that trigger pro-inflammatory cytokines and chemokines, but pathogenic fungi can evade recognition by masking these molecules. Knowledge about which cell wall epitopes are available for immune recognition during human infection could implicate specific ligands and receptors in the symptoms of vaginal candidiasis. To address this important gap, we directly probed the surface of fungi present in fresh vaginal samples obtained both from women with symptomatic Candida vaginitis and from women that are colonized but asymptomatic. We find that the pro-inflammatory cell wall polysaccharide ß-glucan is largely masked from immune recognition, especially on yeast. It is only exposed on a small percentage of hyphal cells, where it tends to co-localize with enhanced levels of chitin. Enhanced ß-glucan availability is only found in symptomatic patients with strong neutrophil infiltration, implicating neutrophils as a possible driver of these cell wall changes. This is especially interesting because neutrophils were recently shown to be necessary and sufficient to provoke enhanced ß-glucan exposure in C. albicans, accompanied by elevated immune responses. Taken together, our data suggest that the architecture of C. albicans cell wall can be altered by environmental stress during vaginal candidiasis.


Assuntos
Candida albicans/imunologia , Candidíase Vulvovaginal/imunologia , Epitopos/imunologia , Polissacarídeos Fúngicos/imunologia , Hifas/imunologia , Infiltração de Neutrófilos , Neutrófilos/imunologia , Adulto , Candida albicans/patogenicidade , Candidíase Vulvovaginal/patologia , Feminino , Humanos , Hifas/patogenicidade , Pessoa de Meia-Idade
19.
Virulence ; 9(1): 954-966, 2018 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-29683763

RESUMO

In this study, we demonstrate, for the first time, that Saccharomyces cerevisiae-based probiotic shows an inhibitory effect on Gardnerella vaginalis infection. This effect is likely due to several actions: direct interference with adherence to vaginal tissues, inhibition of sialidase activity, reduction of vaginal epithelial exfoliation. Gardnerella vaginalis does not induce vaginal inflammation and no inflammatory cytokines were, indeed, produced, by the mouse vagina, neither by Gardnerella vaginalis and by the probiotic. Collectively, our data incite to further investigations on Saccharomyces cerevisiae probiotic as a potential prophylactic or therapeutic agent in the vaginosis caused by Gardnerella vaginalis.


Assuntos
Gardnerella vaginalis/fisiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Probióticos/administração & dosagem , Saccharomyces cerevisiae/fisiologia , Vaginose Bacteriana/tratamento farmacológico , Animais , Antibiose , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Vagina/microbiologia , Vaginose Bacteriana/microbiologia
20.
J Microbiol Immunol Infect ; 51(2): 220-225, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28711440

RESUMO

BACKGROUND: Mycoplasmas are frequently isolated from the genital tract. New molecular PCR-based methods for the detection of mycoplasmas can better define the real epidemiology of these microorganisms. The aim of this study was to evaluate the prevalence of mycoplasmas in a population of childbearing age women by means of PCR. METHODS: This 21-month multicentre observational study was conducted at four Italian clinical microbiology laboratories. Women reporting symptoms of vaginitis/cervicitis, or with history of infertility, pregnancy, miscarriage or preterm birth were included. Detection of Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma hominis, Mycoplasma genitalium was performed from cervical swabs by means of a commercially available multiplex real-time PCR. RESULTS: a total of 1761 women fulfilled the inclusion criteria and were included in the study. The overall prevalence was: U. parvum 38.3%, U. urealyticum 9%, M. hominis 8.6% and M. genitalium 0.6%. The proportion of foreign patients positive for U. parvum was significantly higher compared to Italian patients (37% vs 30.1%, p = 0.007) and also for overall mycoplasma colonization (53.4% vs 45.8%, p = 0.011). The number of symptomatic patients positive for M. hominis was significantly higher than that of negative controls (2.9% vs 1%, p = 0.036). A significant positive trend in mycoplasma colonization was found in relation to the pregnancy week for U. urealyticum (p = 0.015), M. hominis (p = 0.044) and for overall mycoplasma colonization (p = 0.002). CONCLUSION: multiplex RT-PCR can be a valuable tool to evaluate the real epidemiology of cervical mycoplasma colonization.


Assuntos
Colo do Útero/microbiologia , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Mycoplasma hominis/isolamento & purificação , Infecções por Ureaplasma/epidemiologia , Ureaplasma urealyticum/isolamento & purificação , Ureaplasma/isolamento & purificação , Adulto , Feminino , Humanos , Itália , Reação em Cadeia da Polimerase Multiplex , Infecções por Mycoplasma/microbiologia , Mycoplasma genitalium/genética , Mycoplasma hominis/genética , Reação em Cadeia da Polimerase em Tempo Real , Ureaplasma/genética , Infecções por Ureaplasma/microbiologia , Ureaplasma urealyticum/genética , Esfregaço Vaginal/métodos , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/microbiologia
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