Interactions between human keratinocytes and secreted factors from Staphylococcus aureus biofilm and planktonic cultures were investigated using microarray analysis.
Staphylococcus aureus Biofilm and Planktonic cultures differentially impact gene expression, mapk phosphorylation, and cytokine production in human keratinocytes.
Treatment
View SamplesStaphylococcus aureus produces the cyclic dipeptides tyrvalin and phevalin (aureusimine A and B, respectively).
Phevalin (aureusimine B) production by Staphylococcus aureus biofilm and impacts on human keratinocyte gene expression.
Specimen part, Treatment
View SamplesUstilago maydis is a basidiomycete fungus that causes smut disease in maize. Most prominent symptoms of the disease are plant tumors, which can be induced by U. maydis on all aerial parts of the plant. We identified two linked genes, pit1 and pit2, which are specifically expressed during plant colonization. Deletion mutants for either pit1 or pit2 are unable to induce tumor development and elicit plant defense responses.
Two linked genes encoding a secreted effector and a membrane protein are essential for Ustilago maydis-induced tumour formation.
Specimen part, Disease, Disease stage
View SamplesBiofilms have been implicated in delayed wound healing, although the mechanisms by which biofilms impair wound healing are poorly understood. Many species of bacteria produce exotoxins and exoenzymes that may inhibit healing. In addition, oxygen consumption by biofilms, as well as responding leukocytes, may impede wound healing. In this study, we used oxygen microsensors to measure oxygen transects through in vitro-cultured biofilms, biofilms formed in vivo within scabs from a diabetic (db/db) mouse model, and ex vivo human chronic wound specimens. The results show that oxygen levels within mouse scabs had steep gradients that reached minima ranging from 17-72 mmHg on live mice and 6.4-1.1 mmHg on euthanized mice. The oxygen gradients in the mouse scabs were similar to those observed for clinical isolates cultured in vitro and for human ex vivo specimens. No oxygen gradients were observed for heat-killed mouse scabs, suggesting that active metabolism by the viable bacteria and host cells contributed to the reduced oxygen partial pressure of the scabs. To characterize the metabolic activities of the bacteria in the mouse scabs, we performed transcriptomics analyses of Pseudomonas aeruginosa biofilms associated with the db/db mice wounds using Affymetrix microarrays. The results demonstrated that the bacteria expressed genes for metabolic activities associated with cell growth. Interestingly, the transcriptome results indicated that the bacteria within the wounds also experienced oxygen-limitation stress. Among the bacterial genes that were expressed in vivo were genes associated with the Anr-mediated hypoxia-stress response. Other bacterial stress response genes highly expressed in vivo were genes associated with stationary-phase growth, osmotic stress, and RpoH-mediated heat shock stress. Overall, the results support the hypothesis that bacterial biofilms in chronic wounds promote chronicity by contributing to the maintenance of localized low oxygen tensions.
Microsensor and transcriptomic signatures of oxygen depletion in biofilms associated with chronic wounds.
Specimen part, Disease, Time
View SamplesBiofilms have been implicated in delayed wound healing, although the mechanisms by which biofilms impair wound healing are poorly understood. Many species of bacteria produce exotoxins and exoenzymes that may inhibit healing. In addition, oxygen consumption by biofilms, as well as responding leukocytes, may impede wound healing. In this study, we used oxygen microsensors to measure oxygen transects through in vitro-cultured biofilms, biofilms formed in vivo within scabs from a diabetic (db/db) mouse model, and ex vivo human chronic wound specimens. The results show that oxygen levels within mouse scabs had steep gradients that reached minima ranging from 17-72 mmHg on live mice and 6.4-1.1 mmHg on euthanized mice. The oxygen gradients in the mouse scabs were similar to those observed for clinical isolates cultured in vitro and for human ex vivo specimens. No oxygen gradients were observed for heat-killed mouse scabs, suggesting that active metabolism by the viable bacteria and host cells contributed to the reduced oxygen partial pressure of the scabs. To characterize the metabolic activities of the bacteria in the mouse scabs, we performed transcriptomics analyses of Pseudomonas aeruginosa biofilms associated with the db/db mice wounds using Affymetrix microarrays. The results demonstrated that the bacteria expressed genes for metabolic activities associated with cell growth. Interestingly, the transcriptome results indicated that the bacteria within the wounds also experienced oxygen-limitation stress. Among the bacterial genes that were expressed in vivo were genes associated with the Anr-mediated hypoxia-stress response. Other bacterial stress response genes highly expressed in vivo were genes associated with stationary-phase growth, osmotic stress, and RpoH-mediated heat shock stress. Overall, the results support the hypothesis that bacterial biofilms in chronic wounds promote chronicity by contributing to the maintenance of localized low oxygen tensions.
Microsensor and transcriptomic signatures of oxygen depletion in biofilms associated with chronic wounds.
Specimen part, Time
View SamplesWe used microarrays to compare the global programme of gene expression in HTLV-positive, ATL-derived and HTLV-positive in vitro-transformed cell lines with that of uninfected primary CD4 T cells.
Elevated cyclic AMP levels in T lymphocytes transformed by human T-cell lymphotropic virus type 1.
Specimen part
View SamplesThe Arabidopsis cytochrome P450 KLUH (KLU)/CYP78A5 promotes organ growth in a non-cell autonomous manner. To identify genes regulated by KLU activity, homozygous klu-2 mutants carrying constructs for EtOH-inducible overexpression of wild-type KLU (35S::AlcR-AlcA::KLU) or of enzymatically inactive KLU protein (35S::AlcR-AlcA::KLUmut) were induced with EtOH and sampled at 90 min and 240 min after induction for gene expression changes.
Control of plant organ size by KLUH/CYP78A5-dependent intercellular signaling.
No sample metadata fields
View SamplesScope: Soy flour diet (MS) prevented isoflavones from stimulating MCF-7 tumor growth in athymic nude mice, indicating that other bioactive compounds in soy can negate the estrogenic properties of isoflavones. The underlying signal transduction pathways to explain the protective effects of soy flour consumption were studied here.
Isoflavones in soy flour diet have different effects on whole-genome expression patterns than purified isoflavone mix in human MCF-7 breast tumors in ovariectomized athymic nude mice.
Cell line
View SamplesMemory T cells are important for protective immunity against infectious microorganisms. Such protection is achieved by cooperative action of memory T cell populations that differ in their tissue localization and functionality. We report on the identification of the fractalkine receptor CX3CR1 as marker for stratification of memory T cells with cytotoxic effector function from those with proliferative function in both, mice and man. Based on CX3CR1 and CD62L expression levels four distinct memory T cell populations can be distinguished based on their functional properties. Transcriptome and proteome profiling revealed that CX3CR1 expression was superior to CD62L to resolve memory T cell functionality and allowed determination of a core signature of memory T cells with cytotoxic effector function. This identifies a CD62Lhi CX3CR1+ memory T cell population with an identical gene signature to CD62LlowCX3CR1+ effector memory T cells. In lymph nodes, this so far unrecognized CD62LhiCX3CR1+ T cell population shows a distinct migration pattern and anatomic positioning compared to CD62LhiCX3CR1neg TCM. Furthermore, CX3CR1+ memory T cells were scarce or absent during chronic HBV, HCV and HIV infection in man and chronic LCMV infection in mice confirming the value of CX3CR1+ in understanding principles of protective immune memory. Overall design: CD8+ T cells were isolated and directly assessed. After harvesting, cells were immediately lysed in Trizol (Invitrogen) before storage at -80°C for RNA isolation.
Functional classification of memory CD8(+) T cells by CX3CR1 expression.
No sample metadata fields
View SamplesTo gain insight into the biological functions of the highly expressed GLP-1R in Brunners glands, transcriptome analyses were conducted in male GLP-1R-/- and wild-type control mice. Analyses were performed 6 hours after a single s.c. dose of exendin-4 (1.0mg/kg s.c.), following 18 hours of two doses of exendin-4 (1.0 mg/kg s.c., administered at 0 and 9 hours), and in untreated controls. Brunners glands were isolated by laser capture micro dissection and extracted total RNA was used for microarray profiling.
GLP-1 Induces Barrier Protective Expression in Brunner's Glands and Regulates Colonic Inflammation.
Sex, Specimen part, Time
View Samples