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Article in Chinese | WPRIM | ID: wpr-771507


The aim of this paper was to investigate the inhibitory effect of extract of Coptidis Rhizoma(ECR) on invasion of Candida albicans hyphae in vitro.XTT reduction method was used to evaluate the metabolic activity of C.albicans.The colony edge growth of C.albicans was observed by solid medium.The growth of C.albicans hyphae was determined on semi-solid medium.The morphology and viability changes of C.albicans hyphae were assessed by scanning electron microscope and fluorescence microscope.qRT-PCR method was used to detect the ALS3 and SSA1 expression of C.albicans invasin genes.The results showed that the metabolic viability by XTT method detected that the activity of C.albicans was gradually decreased under the intervention of 64,128 and 256 mg·L-1 of ECR respectively.128,256 mg·L-1 of ECR significantly inhibited colony folds and wrinkles on solid medium and the hyphal invasion in semi-solid medium.Scanning electron microscopy and fluorescence microscopy showed that 128,256 mg·L-1 of ECR could inhibit the formation of C.albicans hyphae.qRT-PCR results showed that the expression of invasin gene ALS3 and SSA1 was down-regulated,and especially 256 mg·L-1 of ECR could down-regulate the two genes expression by 4.8,1.68 times respectively.This study showed that ECR can affect the invasiveness of C.albicans by inhibiting the growth of hyphae and the expression of invasin.

Adenosine Triphosphatases , Genetics , Candida albicans , Drugs, Chinese Herbal , Pharmacology , Fungal Proteins , Genetics , Gene Expression Regulation, Fungal , HSP70 Heat-Shock Proteins , Genetics , Hyphae , Microscopy, Electron, Scanning
Braz. j. infect. dis ; 20(2): 160-165, Mar.-Apr. 2016. graf
Article in English | LILACS | ID: lil-780803


Abstract This study was undertaken in order to assess the involvement of Mycobacterium tuberculosis pili (MTP) as an adhesin, invasin, and cytokine inducer in the M. tuberculosis-epithelial cell interaction. A MTP-deficient strain of M. tuberculosis demonstrated a significant reduction of 69.39% (p = 0.047) and 56.20% (p = 0.033) in its ability to adhere to and invade A549 pulmonary epithelial cells, respectively, in comparison with the wild-type strain. Complementation of the MTP-deficient mutant restored its adhesion and invasion capacity back to the wild-type levels. Overall, it was found that similar concentrations of IL-1β, IL-4, IL-6, IL-8, G-CSF, IFN-γ, MCP-1, and TNF-α were induced in A549 cells infected with the MTP-proficient and MTP-deficient strains. However, at 48 h post-infection, the MTP-deficient mutant induced significantly lower levels of TNF-α than the wild-type strain (p = 0.033). Furthermore, at 72 h post-infection, the mutant induced significantly higher levels of IL-8 than the wild-type (p = 0.005). We conclude that MTP is an adhesin/invasin of epithelial cells and, while playing a role in M. tuberculosis entry, they do not appear to largely influence the epithelial cell cytokine response.

Humans , Bacterial Proteins/physiology , Cell Adhesion/physiology , Cytokines/immunology , Fimbriae, Bacterial/physiology , Epithelial Cells/microbiology , Mycobacterium tuberculosis/physiology , Bacterial Proteins/metabolism , Mycobacterium tuberculosis/immunology
J Biosci ; 2015 Mar; 40 (1): 79-90
Article in English | IMSEAR | ID: sea-162020


The use of adenovirus vector-based vaccines is a promising approach for generating antigen-specific immune responses. Improving vaccine potency is necessary in other approaches to address their inadequate protection for the majority of infectious diseases. This study is the first to reconstruct a recombinant replication-defective human adenovirus co-expressing E2 and invasin C-terminal (InvC) glycoproteins (rAd-E2-InvC). rAd-E2-InvC with 2×106 TCID50 was intramuscularly administered two times to CSFV-free pigs at 14 day intervals. No adverse clinical reactions were observed in any of the pigs after the vaccination. The CSFV E2-specific antibody titer was significantly higher in the rAd-E2-InvC group than that in the rAdV-E2 group as measured by NPLA and blocking ELISA. Pigs immunized with rAd-E2-InvC were completely protected against lethal challenge. Neither CSFV RNA nor pathological changes were detected in the tissues after CSFV challenge. These results demonstrate that rAd-E2-InvC could be an alternative to the existing CSF vaccine. Moreover, InvC that acts as an adjuvant could enhance the immunogenicity of rAdV-E2 and induce high CSFV E2-specific antibody titer and protection level.

Rio de Janeiro; s.n; 2010. 182 p. ilus.
Thesis in Portuguese | LILACS | ID: lil-658260


Corynebacterium diphtheriae pode ser isolado tanto de quadros de difteria clássica, quanto de infecções sistêmicas, como endocardite. O fibrinogênio (Fbn) e a fibronectina (Fn) são glicoproteínas presentes na matriz extracelular de tecidos conjuntivos. A influência destas proteínas na patogênese das infecções locais e invasivas causadas por C. diphtheriae é objeto de estudo devido ao fato do bacilo diftérico poder ser encontrado em lesões nas quais o Fbn e a Fn são predominantes, incluindo a pseudomembrana diftérica e vegetações cardíacas presentes na endocardite infecciosa. São crescentes as evidências de que o C. diphtheriae pode, além de aderir, ser internalizado por células em cultura. No presente estudo, investigou-se a participação de C. diphtheriae e das proteínas de superfície 67-72p na aderência à Fn e ao Fbn de plasma humano e a eritrócitos. A aderência às células HEp-2 e internalização também foram analisadas. A participação de 67-72p nos mecanismos de morte celular foi avaliada através das colorações por Azul de Tripan e 4'6-diamidino-2-fenil indol (DAPI), pelo ensaio de redução utilizando dimetil-tiazol-difenil tetrazólio (MTT) e por citometria de fluxo. As 67-72p foram extraídas da superfície da amostra toxigênica C. diphtheriae subsp. mitis CDC-E8392 através de processos mecânicos e precipitação com sulfato de amônio saturado. Análises por SDS-PAGE e immunoblotting detectaram a presença das bandas protéicas de 67 e 72kDa nas amostras toxinogênicas e atoxinogênicas analisadas, as quais pertenciam aos biotipos fermentador e não fermentador de sacarose. C. diphtheriae foi capaz não só de formar agregados na presença de plasma de coelho, mas também de converter Fbn em fibrina independentemente da presença do gene tox. No entanto, a amostra atoxinogênica ATCC 27010 (tox-) foi menos aderente ao Fbn do que a homóloga ATCC 27012 (tox+). A interação bacteriana com eritrócitos foi inibida somente pela Fn. Ligações entre Fn e/ou Fbn com 67-72p foram ...

Corynbacterium diphtheriae have been isolated from classical diphtheria and systemic infections such as endocarditis. Fibrinogen (Fbn) and fibronectin (Fn) are high molecular-weight glycoproteins that may be found in extracellular matrix of connective tissues. Their influence in the pathogenesis of local and in invasive C. diphtheriae infection is object of interest due to the fact that diphtheria bacilli is recovered from lesions where such proteins are predominant, including pharyngeal pseudomembrane and valve heart vegetations in infectious endocarditis. There is growing evidence that C. diphtheriae may adhere to and be internalized by cells in culture. The present study investigated the participation of C. diphtheriae strains and 67-72p, a surface protein, in adherence to human plasma Fn, Fbn, erityrocytes, adherence to and internalization by HEp-2 cells. The participation of 67-72p in promoting cell death was evaluated by the Trypan blue, DAPI staining methods, methylthiazole tetrazolium (MTT) reduction assay and flow cytometry. The 67-72p was extracted from C. diphtheriae subsp. mitis CDC-E8392 toxigenic strain, by mechanical process and ammonium sulfate fractionation. SDS-PAGE and immunoblotting analysis detected the polypeptide bands of 67 and 72 kDa in all toxigenic and nontoxigenic strains from both sucrose-fermenting and non-fermanting biotypes. Diphtheria bacilli were capable to both form bacterial aggregates in rabbit plasma and to convert Fbn to fibrin independently to the presence of tox gene, albeit the ATCC 27010 (tox-) strain was less adherent to Fbn than the paental strain ATCC 27012 (tox+). Bacteria-erythrocytes interaction was inhibited only ...

Bacterial Adhesion , Corynebacterium diphtheriae/isolation & purification , Corynebacterium diphtheriae/pathogenicity , Fibrinogen , Fibronectins , Hemagglutinins/metabolism , Adhesins, Bacterial , Apoptosis , Blood Proteins , Cell Survival , Epithelial Cells/microbiology