Cell-directed-assembly: Directing the formation of nano/bio interfaces and architectures with living cells

Baca, Helen K.; Carnes, Eric C.; Ashley, Carlee E.; Lopez, DeAnna M.; Douthit, Cynthia; Karlin, Shelly; Brinker, C. Jeffrey

doi:10.1016/j.bbagen.2010.09.005

Cited by 34 publications

(29 citation statements)

References 52 publications

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“…Although this question has been the subject of significant attention in recent years, many of the strategies used to isolate and study small groups of cells have used closed systems that have minimal chemical exchange with the outside environment or conditions that support little or no bacterial growth (32)(33)(34)(35)(36)(37)(38)(39). We recently used microtraps to address this question using a P. aeruginosa biosensor strain that produces high levels of GFP on QS activation.…”

Section: Discussionmentioning

confidence: 99%

“…Droplet-based, emulsion, and microfluidic approaches have evolved as high-throughput tools for screening interactions within small groups of isolated bacteria (32)(33)(34)(35)(36)(37)(38)(39)(40). However, these confinement strategies typically offer little control over the spatial arrangement of aggregates, and diffusion of extracellular signals between the confinement volume and the surrounding environment is limited.…”

Section: -10mentioning

confidence: 99%

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Real-time monitoring of quorum sensing in 3D-printed bacterial aggregates using scanning electrochemical microscopy

Connell

Kim

Shear

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

168

162

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Microbes frequently live in nature as small, densely packed aggregates containing ∼10 1 -10 5 cells. These aggregates not only display distinct phenotypes, including resistance to antibiotics, but also, serve as building blocks for larger biofilm communities. Aggregates within these larger communities display nonrandom spatial organization, and recent evidence indicates that this spatial organization is critical for fitness. Studying single aggregates as well as spatially organized aggregates remains challenging because of the technical difficulties associated with manipulating small populations. Micro-3D printing is a lithographic technique capable of creating aggregates in situ by printing protein-based walls around individual cells or small populations. This 3D-printing strategy can organize bacteria in complex arrangements to investigate how spatial and environmental parameters influence social behaviors. Here, we combined micro-3D printing and scanning electrochemical microscopy (SECM) to probe quorum sensing (QS)-mediated communication in the bacterium Pseudomonas aeruginosa. Our results reveal that QS-dependent behaviors are observed within aggregates as small as 500 cells; however, aggregates larger than 2,000 bacteria are required to stimulate QS in neighboring aggregates positioned 8 μm away. These studies provide a powerful system to analyze the impact of spatial organization and aggregate size on microbial behaviors.Pseudomonas aeruginosa | scanning electrochemical microscopy | quorum sensing | 3D printing | pyocyanin B acterial populations are often found in nature as small, densely packed aggregates containing ∼10 1 -10 5 cells (1-5). These aggregates serve as building blocks for larger biofilm communities as well as a primary mode of transmission for pathogenic microbes (5-8). Similar to biofilm communities, aggregates develop microscale physical and chemical heterogeneity and display clinically relevant phenotypes, including enhanced antibiotic resistance (2,(8)(9)(10)(11)(12)(13)(14)(15)(16). Moreover, aggregate sizes containing as few as 10 3 bacteria have been shown to engage in quorum sensing (QS)-mediated behaviors (17-21). In its simplest form, QS is a communication strategy that allows bacteria to effectively monitor their population density through the secretion and sensing of extracellular signals (7,(22)(23)(24). When the population reaches a specific density, activation of the QS regulatory cascade results in enhanced transcription of a defined set of genes. These genes control distinct behaviors, including virulence, in the opportunistic pathogen Pseudomonas aeruginosa (25). In addition to displaying QS-mediated behaviors, bacterial aggregates have been shown to interact with neighboring aggregates both in vitro and in vivo (9,(26)(27)(28). Indeed, these interactions have a profound impact on virulence and are often mediated by small diffusible molecules (8-10, 22, 29-31).Despite the prevalence of aggregates in nature, understanding the mechanisms controlling their behavior and intera...

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Section: Discussionmentioning

confidence: 99%

Section: -10mentioning

confidence: 99%

Real-time monitoring of quorum sensing in 3D-printed bacterial aggregates using scanning electrochemical microscopy

Connell

Kim

Shear

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

168

162

View full text Add to dashboard Cite

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“…Manufacturing procedures that attach a benign sugar such as lactose to the surfaces of silver nanoparticles can also markedly enhance nanoparticle uptake into malignant, but not healthy cells 28 . Plant extracts, DNA, and proteins also guide bottom-up manufacturing via self-assembly of silica precursors into crystalline silica nanostructures 54 , 55 that can resist drying in some preparations 56 …”

Section: Nanoscale Forms Of Natural Products For Cancer Treatmentmentioning

confidence: 99%

Integrative Nanomedicine: treating Cancer with Nanoscale Natural Products

Bell

Sarter

Koithan

et al. 2014

Glob Adv Health Med

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Finding safer and more effective treatments for specific cancers remains a significant challenge for integrative clinicians and researchers worldwide. One emerging strategy is the use of nanostructured forms of drugs, vaccines, traditional animal venoms, herbs, and nutraceutical agents in cancer treatment. The recent discovery of nanoparticles in traditional homeopathic medicines adds another point of convergence between modern nanomedicine and alternative interventional strategies. A way in which homeopathic remedies could initiate anticancer effects includes cell-to-cell signaling actions of both exogenous and endogenous (exosome) nanoparticles. The result can be a cascade of modulatory biological events with antiproliferative and pro-apoptotic effects. The Banerji Protocols reflect a multigenerational clinical system developed by homeopathic physicians in India who have treated thousands of patients with cancer. A number of homeopathic remedy sources from the Banerji Protocols (eg, Calcarea phosphorica; Carcinosin—tumor-derived breast cancer tissue prepared homeopathically) overlap those already under study in nonhomeopathic nanoparticle and nanovesicle tumor exosome cancer vaccine research. Past research on antineoplastic effects of nano forms of botanical extracts such as Phytolacca, Gelsemium, Hydrastis, Thuja, and Ruta as well as on homeopathic remedy potencies made from the same types of source materials suggests other important overlaps. The replicated finding of silica, silicon, and nano-silica release from agitation of liquids in glassware adds a proven nonspecific activator and amplifier of immunological effects. Taken together, the nanoparticulate research data and the Banerji Protocols for homeopathic remedies in cancer suggest a way forward for generating advances in cancer treatment with natural product–derived nanomedicines.

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“…27,51 Available data indicate that the nanoparticles could convey such organism-specific information with chemical, electromagnetic, magnetic, structural, and/or even optical or quantum effects. 21,102,135,143–146 …”

Section: Homeopathic Remedies Are Source Nanoparticles Not Bulk Matementioning

confidence: 99%

Testing the nanoparticle-allostatic cross-adaptation-sensitization model for homeopathic remedy effects

2013

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Key concepts of the Nanoparticle-Allostatic Cross-Adaptation-Sensitization (NPCAS) Model for the action of homeopathic remedies in living systems include source nanoparticles as low level environmental stressors, heterotypic hormesis, cross-adaptation, allostasis (stress response network), time-dependent sensitization with endogenous amplification and bidirectional change, and self-organizing complex adaptive systems. The model accommodates the requirement for measurable physical agents in the remedy (source nanoparticles and/or source adsorbed to silica nanoparticles). Hormetic adaptive responses in the organism, triggered by nanoparticles; bipolar, metaplastic change, dependent on the history of the organism. Clinical matching of the patient’s symptom picture, including modalities, to the symptom pattern that the source material can cause (cross-adaptation and cross-sensitization). Evidence for nanoparticle-related quantum macro-entanglement in homeopathic pathogenetic trials. This paper examines research implications of the model, discussing the following hypotheses: Variability in nanoparticle size, morphology, and aggregation affects remedy properties and reproducibility of findings. Homeopathic remedies modulate adaptive allostatic responses, with multiple dynamic short- and long-term effects. Simillimum remedy nanoparticles, as novel mild stressors corresponding to the organism’s dysfunction initiate time-dependent cross-sensitization, reversing the direction of dysfunctional reactivity to environmental stressors. The NPCAS model suggests a way forward for systematic research on homeopathy. The central proposition is that homeopathic treatment is a form of nanomedicine acting by modulation of endogenous adaptation and metaplastic amplification processes in the organism to enhance long-term systemic resilience and health.

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Cell-directed-assembly: Directing the formation of nano/bio interfaces and architectures with living cells

Cited by 34 publications

References 52 publications

Real-time monitoring of quorum sensing in 3D-printed bacterial aggregates using scanning electrochemical microscopy

Real-time monitoring of quorum sensing in 3D-printed bacterial aggregates using scanning electrochemical microscopy

Integrative Nanomedicine: treating Cancer with Nanoscale Natural Products

Testing the nanoparticle-allostatic cross-adaptation-sensitization model for homeopathic remedy effects

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