Cell nuclear size and shape are strictly regulated, with aberrations often leading to or being indicative of disease. Nuclear mechanics are critically responsible for intracellular responses to extracellular cues, such as the nanotopography of the external environment. Silicon nanoneedle (SiNN) arrays are tunable, engineered cell culture substrates that permit precise, nanoscale modifications to a cell's external environment to probe mechanotransduction and intracellular signaling. We use a library of four different SiNN arrays to investigate the immediate and downstream effects of controlled geometries of nanotopographical cues on the nuclear integrity/dynamics of human immortalized somatic and renewing stem cell types. We quantify the significant, albeit different, nuclear shape changes that both cell types undergo, which suggest that cellular responses to SiNN arrays are more comparable to three-dimensional (3D) environments than traditional flat cultureware. We show that nanotopography-induced effects on nuclear envelope integrity, protein localization, and focal adhesion complex formation are cell-dependent. Migration is shown to be dramatically impeded for human neural progenitor cells (hNPCs) on nanotopographies compared to flat substrates but not for somatic cells. Our results indicate an additional layer of complexity in cellular mechanotransduction, which warrants closer attention in the context of engineered substrates and scaffolds for clinical applications.

Tunable vertically aligned nanostructures, usually fabricated using inorganic materials, are powerful nanoscale tools for advanced cellular manipulation. However, nanoscale precision typically requires advanced nanofabrication machinery and involves high manufacturing costs. By contrast, polymeric nanoneedles (NNs) of precise geometry can be produced by replica molding or nanoimprint lithography—rapid, simple, and cost-effective. Here, cytocompatible polymeric arrays of NNs are engineered with identical topographies but differing stiffness, using polystyrene (PS), SU8, and polydimethylsiloxane (PDMS). By interfacing the polymeric NN arrays with adherent and suspension mammalian cells, and comparing the cellular responses of each of the three polymeric substrates, the influence of substrate stiffness from topography on cell behavior is decoupled. Notably, the ability of PS, SU8, and PDMS NNs is demonstrated to facilitate mRNA delivery to GPE86 cells with 26.8% ± 3.5%, 33.2% ± 7.4%, and 30.1% ± 4.1% average transfection efficiencies, respectively. Electron microscopy reveals the intricacy of the cell–NN interactions; and immunofluorescence imaging demonstrates that enhanced endocytosis is one of the mechanisms of PS NN-mediated intracellular delivery, involving the endocytic proteins caveolin-1 and clathrin heavy chain. The results provide insights into the interfacial interactions between cells and polymeric NNs, and their related intracellular delivery mechanisms.

Tunable vertically aligned nanostructures, usually fabricated using inorganic materials, are powerful nanoscale tools for advanced cellular manipulation. However, nanoscale precision typically requires advanced nanofabrication machinery and involves high manufacturing costs. By contrast, polymeric nanoneedles (NNs) of precise geometry can be produced by replica molding or nanoimprint lithography—rapid, simple, and cost‐effective. Here, cytocompatible polymeric arrays of NNs are engineered with identical topographies but differing stiffness, using polystyrene (PS), SU8, and polydimethylsiloxane (PDMS). By interfacing the polymeric NN arrays with adherent and suspension mammalian cells, and comparing the cellular responses of each of the three polymeric substrates, the influence of substrate stiffness from topography on cell behavior is decoupled. Notably, the ability of PS, SU8, and PDMS NNs is demonstrated to facilitate mRNA delivery to GPE86 cells with 26.8% ± 3.5%, 33.2% ± 7.4%, and 30.1% ± 4.1% average transfection efficiencies, respectively. Electron microscopy reveals the intricacy of the cell–NN interactions; and immunofluorescence imaging demonstrates that enhanced endocytosis is one of the mechanisms of PS NN‐mediated intracellular delivery, involving the endocytic proteins caveolin‐1 and clathrin heavy chain. The results provide insights into the interfacial interactions between cells and polymeric NNs, and their related intracellular delivery mechanisms.

One-dimensional vertically aligned silicon nanostructures, in particular vertically-aligned nanowires, nanotubes, and nanostraws, have been extensively explored and have risen as promising materials for cell–nanomaterial interface applications. This includes intracellular delivery/extraction, biosensing, nanoelectrode-based electrophysiology, mechanotransduction, immunomodulation, and advanced cellular studies. Such vertically aligned nanostructures can be fabricated by multiple nanofabrication routes with high precision control over their topological parameters tailored for diverse cellular applications. Here we provide an overview of engineered cell–material interfaces of vertically aligned silicon nanostructures, the fabrication and functionalization of silicon nanowires, and the influence of silicon nanowire geometry on fundamental cell behaviors. Furthermore, we highlight recent progress and likely future developments related to nanostructures for intracellular signaling and delivery, and related to the integration of nanostructures in electroporation systems.

Medical Journal of AustraliaVolume 216, Issue 3 p. 158-158 Letters Toward ethical regulation of mitochondrial donation Julian Koplin, Corresponding Author Julian Koplin [email protected] orcid.org/0000-0002-2752-7334 Monash Bioethics Centre, Monash University, Melbourne, VICSearch for more papers by this authorEsther Lestrell, Esther Lestrell Monash University, Melbourne, VICSearch for more papers by this author Julian Koplin, Corresponding Author Julian Koplin [email protected] orcid.org/0000-0002-2752-7334 Monash Bioethics Centre, Monash University, Melbourne, VICSearch for more papers by this authorEsther Lestrell, Esther Lestrell Monash University, Melbourne, VICSearch for more papers by this author First published: 03 February 2022 https://doi.org/10.5694/mja2.51396Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References 1 House of Representatives, Parliament of the Commonwealth of Australia. Mitochondrial Donation Law Reform (Maeve’s Law) Bill 2021. https://parlinfo.aph.gov.au/parlInfo/download/legislation/bills/r6697_first-reps/toc_pdf/21043b01.pdf;fileType=application%2Fpdf (viewed Jan 2022). 2Alikani M, Fauser BCJ, García-Valesco JA, et al. First birth following spindle transfer for mitochondrial replacement therapy: hope and trepidation. Reprod Biomed Online 2017; 34: 333–336. 3 Australian Government Department of Health. Legalising mitochondrial donation in Australia: public consultation paper. https://consultations.health.gov.au/strategic-policy/mitochondrial-donation-in-australia/supporting_documents/Mitochondrial%20Donation%20%20Public%20Consultation%20Paper.pdf (viewed Jan 2022). Volume216, Issue3February 2022Pages 158-158 ReferencesRelatedInformation

Australia has recently legalised mitochondrial donation. However, key ethical and legal issues still need to be addressed. This paper maps the relevant issues and offers some suggestions for how they ought to be resolved.

Neurodegenerative disorders are a widespread global health concern caused by aging, disease, and trauma, for which there are limited treatment options. Stem cell therapies, tissue engineering, and nanobiotechnologies offer hope for improved therapeutic delivery approaches, as well as tissue repair and regenerative medicine interventions. The complexity of the human brain, coupled with its limited availability for research, makes human neural lineage cells and their precursor stem cells integral to the further understanding of brain functions in health, development, and disease. Engineered nanomaterials provide highly specialized microenvironments, enabling precise interrogation of the impact of external and spatial stimuli on human neural cells in vitro, greatly advancing the knowledge of human neural function. Interacting with neural cells at the nanoscale, vertically aligned nanostructured (VA-NS) arrays can influence cell fate and aid in more efficient cell reprogramming, and lend themselves to the development of highly targeted, sensitive signal transducer platforms suitable for in vivo monitoring of neural cell health and activity. This perspective highlights the current state of stem cell nanoneurobiology, specifically focusing on interdisciplinary advances made by VA-NS arrays to manipulate human neural stem cells in translatable research applications. Current challenges and identify are discussed underexplored and emerging future research areas.

Engineered nano-bio cellular interfaces bring together well-defined nanoscale material morphologies with organic living systems. These extraordinarily complex interfaces are set to produce radical advances in the life sciences, through fundamental research in the emerging multidisciplinary field of cellular nano-biotechnology. We examine the role of a particular class of nanostructured platform: vertically aligned nanowire (VA-NW) arrays. These arrays feature diverse nanoscale topographies that enable unprecedented manipulation of cell functions and processes in vivo, in situ and in vitro. While the platform still requires further optimisation, recent use of the arrays – for in vivo transfection, non-destructive intracellular sampling and to gain fundamental insights into cellular responses to extracellular topographic cues – effectively demonstrates the platforms’ potential. We review innovative applications that show the repertoire of VA-NW arrays as highly efficient, universal, scalable intracellular delivery and sampling platforms, which presage prospects for clinical translation. We analyse the mechanisms by which VA-NW arrays facilitate delivery of bioactive cargos, and discuss the state of current knowledge about effects of nanowire topography on the cell-nanowire interface.

The field of dispute resolution has long been at the forefront of modernising legal education. Continuing this tradition, this chapter presents findings from an evaluation of an exercise introduced into the core law school curriculum at Monash University in Australia. In our compulsory litigation and dispute resolution units, we built an experiential exercise in which students resolved a dispute using both an online dispute resolution (ODR) platform and more traditional face-to-face mediation role-play. Students completed a short survey about their experience of the portal (n=64, response rate 30 per cent) and provided their reflective journals about the exercise for analysis (n=55). Drawing on the findings, we consider the benefits and limitations of this approach for facilitating students’ exposure to ODR. We explore themes including student understanding of ODR’s impacts on dispute processes and outcomes; appropriate conduct in dispute resolution settings; and the challenges of computer-mediated communication. We also identify means by which experiential activities can draw students’ attention to power disparities and access to justice challenges in ODR to develop their critical thinking about the rapid developments in this field.