Tag Archives: PeerRev

Hemoglobin and its role in the oocyte and early embryo

6 May 2019:

Hemoglobin expression in reproductive cells and the role of hemoglobin on oocyte and early embryo development is the focus of this latest CNBP review paper published in the journal ‘Biology of Reproduction’ (lead author Megan Lim based at the University of Adelaide).

Journal: Biology of Reproduction.

Publication title: Hemoglobin: potential roles in the oocyte and early embryo.

Authors: Megan Lim, Hannah M Brown, Karen L Kind, Jeremy G Thompson, Kylie R Dunning.

Abstract: Hemoglobin (Hb) is commonly known for its capacity to bind and transport oxygen and carbon dioxide in erythroid cells. However, it plays additional roles in cellular function and health due to its capacity to bind other gases including nitric oxide. Further, Hb acts as a potent antioxidant, quenching reactive oxygen species. Despite its potential roles in cellular function, the preponderance of Hb research remains focused on its role in oxygen regulation. There is increasing evidence that Hb expression is more ubiquitous than previously thought, with Hb and its variants found in a myriad of cell types ranging from macrophages to spermatozoa. The majority of non-erythroid cell types that express Hb are situated within hypoxic environments, suggesting Hb may play a role in hypoxia-inducible factor (HIF)-regulated gene expression by controlling the level of oxygen available or as an adaptation to low oxygen providing a mechanism to store oxygen. Oocyte maturation and preimplantation embryo development occur within the low oxygen environments of the antral follicle and oviduct/uterus, respectively. Interestingly, Hb was recently found in human cumulus and granulosa cells and murine cumulus-oocyte complexes (COCs) and preimplantation embryos. Here, we consolidate and analyze the research generated to-date on Hb expression in non-erythroid cells with a particular focus on reproductive cell types. We outline future directions of this research to elucidate the role of Hb during oocyte maturation and preimplantation embryo development and finally, we explore the potential clinical applications and benefits of Hb supplementation during the in vitro culture of gametes and embryos.

New cytokine sensing device developed

1 May 2019:

A molecular imprinted polymer biosensing device (developed on stainless steel) that can successfully detect cytokines has been reported by CNBP researchers. Cytokines are proteins secreted by cells that stimulate surrounding cells into specific action and are important to an organism’s immune responses. The finding was reported in the journal ‘Sensors and Actuators B: Chemical’ with the lead author of the publication being CNBP’s Fei Deng based at UNSW Sydney.

Journal: Sensors and Actuators B: Chemical.

Publication title: Molecularly imprinted polymer-based reusable biosensing device on stainless steel for spatially localized detection of cytokine IL-1β.

Authors: Fei Deng, Ewa M. Goldys, Guozhen Liu.

Abstract: A molecularly imprinted polymer (MIP) based biosensing device on stainless steel (SS) for detection of locally variable concentration of cytokine interleukin-1β (IL-1β) was successfully developed using a sandwich assay scheme. The SS surface was firstly modified with a layer of polydopamine (PDA) followed by the attachment of a layer of poly(ethyleneimine) (PEI) by electrostatic adsorption. Subsequently, the template protein IL-1β was adsorbed on the PEI terminated SS surface due to electrostatic adsorption. A PDA imprinting film was then in-situ synthesized on the surface of the modified SS substrate with incorporated template cytokine. Finally, the template was washed off the SS substrate leaving behind cavities with specific shape and capable of capturing cytokines thus forming a MIP biosensing interface. After exposure to the analyte IL-1β, the MIP biosensing device was incubated with IL-1β detection antibody-modified fluorescent polystyrene beads allowing to determine the amount of captured IL-1β based on fluorescence intensity. The device has been demonstrated to detect IL-1β with low detection limit of 10.2 pg mL−1, and a linear detection range of 25–400 pg mL−1. This MIP biosensing device can be regenerated more than three times with coefficient of variation 2.08%. The device was applied for the detection of IL-1β secreted by rat macrophages, where the good specificity and selectivity were achieved. MIP serves in this device as a superior substitute of antibody with exceptional stability and reusability. The MIP based biosensing technology presented in our work paves a new way for developing a universal and robust sensing platform for the detection of spatially localised small proteins with low physical concentration.

Towards a deployable device for cytokine sensing

29 April 2019:

A new research publication (lead author CNBP PhD student Fuyuan Zhang) reports on real-time sensing and detection of cytokines using a 3D optical fibre.

Journal: Molecular Systems Design & Engineering.

Publication title: IFN-γ-induced signal-on fluorescence aptasensors: from hybridization chain reaction amplification to 3D optical fiber sensing interface towards a deployable device for cytokine sensing.

Authors: Fuyuan Zhang, Fei Deng, Guo-Jun Liu, Ryan Middleton, David W. Inglis, Ayad Anwer, Shuo Wang and  Guozhen Liu.

Abstract: Interferon-gamma (IFN-γ), a proinflammatory cytokine, has been used as an early indicator of multiple infectious diseases or tumors. In order to explore the detection capability of a commonly used anti-IFN-γ aptamer, a simple target induced strand-displacement aptasensing strategy was tested by introducing three different complementary strands and two different signal/quencher pairs. The Texas red/BHQ2-based sensor showed the best affinity constant (Kd) of 21.87 ng mL−1. It was found that the strand-displacement aptasensing strategy was impacted by the complementary position and length of the complementary strands. Additionally, the hybridization chain reaction (HCR) amplification strategy was introduced, yielding a 12-fold improved sensitivity of 0.45 ng mL−1. In order to further explore the sensing platform for spatially localized cytokine detection, the Texas red/BHQ2-based strand-displacement aptasensor was successfully fabricated on the 3D optical fiber surface to achieve a deployable sensing device for monitoring IFN-γ based on the fluorescence spots counting strategy. Finally, the three developed aptasensing strategies (strand-displacement strategy, HCR amplification strategy, 3D optical fiber aptasensor) were applied for detection of IFN-γ secreted by PBMCs with comparable results to those of ELISA. The deployable 3D optical fiber aptasensor with the superior sensitivity is potential to be used for detection of spatially localized IFN-γ in vivo.

In-body fibre optic imaging to go 3D

26 April 2019:

An advanced new method has been developed by CNBP researchers that may open the door to 3D microscopy in hard-to-reach areas of the human body.

It sees the successful miniaturization of a 3D imaging technique called ‘light field imaging’, taken to extreme new levels, making in-body application possible.

It could find significant application in diagnostic procedures called optical biopsies, where suspicious tissue is investigated during medical endoscopic procedures.

Reported in the journal ‘Science Advances’, project lead of the innovative imaging approach is Dr Antony Orth, Research Fellow at the RMIT University node of the CNBP (pictured).

The paper can be accessed below or read the media release here.

Journal: Science Advances.

Publication title: Optical fiber bundles: Ultra-slim light field imaging probes.

Authors: A. Orth, M. Ploschner, E. R. Wilson, I.S. Maksymov and B. C. Gibson.

Abstract: Optical fiber bundle microendoscopes are widely used for visualizing hard-to-reach areas of the human body. These ultrathin devices often forgo tunable focusing optics because of size constraints and are therefore limited to two-dimensional (2D) imaging modalities. Ideally, microendoscopes would record 3D information for accurate clinical and biological interpretation, without bulky optomechanical parts. Here, we demonstrate that the optical fiber bundles commonly used in microendoscopy are inherently sensitive to depth information. We use the mode structure within fiber bundle cores to extract the spatio-angular description of captured light rays—the light field—enabling digital refocusing, stereo visualization, and surface and depth mapping of microscopic scenes at the distal fiber tip. Our work opens a route for minimally invasive clinical microendoscopy using standard bare fiber bundle probes. Unlike coherent 3D multimode fiber imaging techniques, our incoherent approach is single shot and resilient to fiber bending, making it attractive for clinical adoption.

Below – Modal structure in optical fiber bundles captures light field information. Credit Antony Orth, RMIT University.

Binding mechanisms of solid-binding peptides

5 April 2019:

A new review article by CNBP PhD student Rachit Bansal and CNBP Associate Investigators (Anwar Sunna, Andrew Care and Tiffany Walsh) reports on experimental tools to study the binding mechanism of synthetic peptides to solid materials. The review provides insights into the role of these peptides as molecular building blocks for nanobiotechnology.

Journal: New Biotechnology.

Publication title: Experimental and theoretical tools to elucidate the binding mechanisms of solid-binding peptides.

Authors: Rachit Bansal, Andrew Care, Megan S. Lord, Tiffany R. Walsh, Anwar Sunna.

Abstract: The interactions between biomolecules and solid surfaces play an important role in designing new materials and applications which mimic nature. Recently, solid-binding peptides (SBPs) have emerged as potential molecular building blocks in nanobiotechnology. SBPs exhibit high selectivity and binding affinity towards a wide range of inorganic and organic materials. Although these peptides have been widely used in various applications, there is a need to understand the interaction mechanism between the peptide and its material substrate, which is challenging both experimentally and theoretically. This review describes the main characterisation techniques currently available to study SBP-surface interactions and their contribution to gain a better insight for designing new peptides for tailored binding.

Liquid-metal nanoparticles focus UV light

29 March 2019:

Liquid-metal nanoparticles can focus ultraviolet light at the nanoscale. Read more in a publication reporting on the UV plasmonic properties of colloidal gallium-indium particles (lead author CNBP Associate Investigator Dr Philipp Reineck, RMIT University).

Journal: Scientific Reports.

Publication title: UV plasmonic properties of colloidal liquid-metal eutectic gallium-indium alloy nanoparticles.

Authors: Philipp Reineck, Yiliang Lin, Brant C. Gibson, Michael D. Dickey, Andrew D. Greentree, Ivan S. Maksymov.

Abstract: Nanoparticles made of non-noble metals such as gallium have recently attracted significant attention due to promising applications in UV plasmonics. to date, experiments have mostly focused on solid and liquid pure gallium particles immobilized on solid substrates. However, for many applications, colloidal liquid-metal nanoparticle solutions are vital. Here, we experimentally demonstrate strong UV plasmonic resonances of eutectic gallium-indium (eGaIn) liquid-metal alloy nanoparticles suspended in ethanol. We rationalise experimental results through a theoretical model based on Mie theory. our results contribute to the understanding of UV plasmon resonances in colloidal liquid-metal eGaIn nanoparticle suspensions. they will also enable further research into emerging applications of UV plasmonics in biomedical imaging, sensing, stretchable electronics, photoacoustics, and electrochemistry.

Visualizing neuroinflammation

21 March 2019:

A new time-gated microscopy approach has been reported by CNBP researchers that will help neurobiologists better visualize neurokine signaling (and other) molecules in cells or tissue samples. Lead author of the publication is CNBP researcher Dr Lindsay Parker, Macquarie University.

Journal: Journal of Neuroinflammation.

Publication title:  Visualizing neuroinflammation with fluorescence and luminescent lanthanide-based in situ hybridization.

Authors: Lindsay M. Parker, Nima Sayyadi, Vasiliki Staikopoulos, Ashish Shrestha, Mark R. Hutchinson and Nicolle H. Packer.


Neurokine signaling via the release of neurally active cytokines arises from glial reactivity and is mechanistically implicated in central nervous system (CNS) pathologies such as chronic pain, trauma, neurodegenerative diseases, and complex psychiatric illnesses. Despite significant advancements in the methodologies used to conjugate, incorporate, and visualize fluorescent molecules, imaging of rare yet high potency events within the CNS is restricted by the low signal to noise ratio experienced within the CNS. The brain and spinal cord have high cellular autofluorescence, making the imaging of critical neurokine signaling and permissive transcriptional cellular events unreliable and difficult in many cases.

In this manuscript, we developed a method for background-free imaging of the transcriptional events that precede neurokine signaling using targeted mRNA transcripts labeled with luminescent lanthanide chelates and imaged via time-gated microscopy. To provide examples of the usefulness this method can offer to the field, the mRNA expression of toll-like receptor 4 (TLR4) was visualized with traditional fluorescent in situ hybridization (FISH) or luminescent lanthanide chelate-based in situ hybridization (LISH) in mouse BV2 microglia or J774 macrophage phenotype cells following lipopolysaccharide stimulation. TLR4 mRNA staining using LISH- and FISH-based methods was also visualized in fixed spinal cord tissues from BALB/c mice with a chronic constriction model of neuropathic pain or a surgical sham model in order to demonstrate the application of this new methodology in CNS tissue samples.

Significant increases in TLR4 mRNA expression and autofluorescence were visualized over time in mouse BV2 microglia or mouse J774 macrophage phenotype cells following lipopolysaccharide (LPS) stimulation. When imaged in a background-free environment with LISH-based detection and time-gated microscopy, increased TLR4 mRNA was observed in BV2 microglia cells 4 h following LPS stimulation, which returned to near baseline levels by 24 h. Background-free imaging of mouse spinal cord tissues with LISH-based detection and time-gated microscopy demonstrated a high degree of regional TLR4 mRNA expression in BALB/c mice with a chronic constriction model of neuropathic pain compared to the surgical sham model.

Advantages offered by adopting this novel methodology for visualizing neurokine signaling with time-gated microscopy compared to traditional fluorescent microscopy are provided.

Automated detection of eye surface cancer

20 March 2019:

A new automated non-invasive technique for diagnosing eye surface cancer (ocular surface squamous neoplasia or OSSN) has been developed by CNBP researchers and collaborators. The technique has the potential to reduce the need for biopsies, prevent therapy delays and make treatment far more effective for patients.

Reported in a clinical journal ‘The Ocular Surface’, the innovative method comprises the custom-building of an advanced imaging microscope in association with state-of-the-art computing and artificial intelligence operation. The result is an automated system that is able to successfully identify between diseased and non-diseased eye tissue, in real-time, through a simple scanning process.

“Clinical symptoms of OSSN are known to be variable and in early stages can be extremely hard to detect so patients may experience delays in treatment or be inaccurately diagnosed,” says Mr Habibalahi, Researcher at the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP) and lead scientist on the project.

“The early detection of OSSN is critical as it supports simple and more curative treatments such as topical therapies whereas advanced lesions may require eye surgery or even the removal of the eye, and also has the risk of mortality,” he says.

What Mr Habibalahi and the research team have developed is a technological approach that utilises the power of both microscopy and cutting-edge machine learning.

“Our hi-tech system scans the natural light given off by specific cells of the eye, after being stimulated by safe levels of artificial light. Diseased cells have their own specific ‘light-wave’ signature which our specially designed computational algorithm is then able to identify providing a quick and efficient diagnosis,” says Mr Habibalahi.

Read the full media release here.

Journal: The Ocular Surface.

Publication title: Novel automated non invasive detection of ocular surface squamous neoplasia using multispectral autofluorescence imaging.

Authors: Abbas Habibalahi, Chandra Bala, Alexandra Allende, Ayad G.Anwer, Ewa M.Goldys.


Diagnosing Ocular surface squamous neoplasia (OSSN) using newly designed multispectral imaging technique.

Eighteen patients with histopathological diagnosis of Ocular Surface Squamous Neoplasia (OSSN) were recruited. Their previously collected biopsy specimens of OSSN were reprocessed without staining to obtain auto fluorescence multispectral microscopy images. This technique involved a custom-built spectral imaging system with 38 spectral channels. Inter and intra-patient frameworks were deployed to automatically detect and delineate OSSN using machine learning methods. Different machine learning methods were evaluated, with K nearest neighbor and Support Vector Machine chosen as preferred classifiers for intra- and inter-patient frameworks, respectively. The performance of the technique was evaluated against a pathological assessment.

Quantitative analysis of the spectral images provided a strong multispectral signature of a relative difference between neoplastic and normal tissue both within each patient (at p < 0.0005) and between patients (at p < 0.001). Our fully automated diagnostic method based on machine learning produces maps of the relatively well circumscribed neoplastic-non neoplastic interface. Such maps can be rapidly generated in quasi-real time and used for intraoperative assessment. Generally, OSSN could be detected using multispectral analysis in all patients investigated here. The cancer margins detected by multispectral analysis were in close and reasonable agreement with the margins observed in the H&E sections in intra- and inter-patient classification, respectively.

This study shows the feasibility of using multispectral auto-florescence imaging to detect and find the boundary of human OSSN. Fully automated analysis of multispectral images based on machine learning methods provides a promising diagnostic tool for OSSN which can be translated to future clinical applications.

Osteoarthritis assessment to go hi-tech

13 March 2019:

CNBP scientists have reported an advanced new imaging technique that allows the condition of joint cartilage to be examined—right down to a molecular level. The technique has potential for diagnostics and treatment-planning of cartilage disease and impairment, including for osteoarthritis.

“Damage and degradation of cartilage around joints leads to severe pain and loss of mobility,” says Dr Saabah Mahbub, Research Fellow at the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP) and lead author of the published study.

“We need a tool to help us to determine objectively, the degree of problem that the joint cartilage is exhibiting. We then need a way to be able to monitor the effectiveness of any cartilage regeneration therapies that are able to be undertaken,” he says.

“Ideally we need to be able to do this monitoring at a molecular level and in a minimally invasive way.”

A cutting-edge technique termed hyperspectral imaging was used by Dr Mahbub to achieve this. This combined the power of an advanced optical microscope together with high powered data analysis, to measure and image the electromagnetic light-waves being given off by the cartilage tissue and cartilage cells known as chondrocytes.

“In this study, we applied our advanced hyperspectral microscopy to osteoarthritic human cartilage—to investigate its capacity to generate molecular data and to help us characterise the cartilage disease-state, as well as to examine potential treatment effects,” he says.

Read the full media release here.

Journal: Scientific Reports.

Publication title: Non-Invasive Monitoring of Functional state of Articular Cartilage tissue with Label-Free Unsupervised Hyperspectral Imaging.

Authors: Saabah B. Mahbub, Anna Guller, Jared M. Campbell, Ayad G. Anwer, Martin E. Gosnell, Graham Vesey & Ewa M. Goldys.

Abstract: Damage and degradation of articular cartilage leads to severe pain and loss of mobility. the development of new therapies for cartilage regeneration for monitoring their effect requires further study of cartilage, ideally at a molecular level and in a minimally invasive way. Hyperspectral microscopy is a novel technology which utilises endogenous fluorophores to non-invasively assess the molecular composition of cells and tissue. In this study, we applied hyperspectral microscopy to healthy bovine articular cartilage and osteoarthritic human articular cartilage to investigate its capacity to generate informative molecular data and characterise disease state and treatment effects. We successfully demonstrated label-free fluorescence identification of collagen type I and II – isolated in cartilage here for the first time and the co-enzymes free NADH and FAD which together give the optical redox ratio that is an important measure of metabolic activity. the intracellular composition of chondrocytes was also examined. Differences were observed in the molecular ratios within the superficial and transitional zones of the articular cartilage which appeared to be influenced by disease state and treatment. These findings show that hyperspectral microscopy could be useful for investigating the molecular underpinnings of articular cartilage degradation and repair. As it is non-invasive and non-destructive, samples can be repeatedly assessed over time, enabling true time-course experiments with in-depth molecular data. Additionally, there is potential for the hyperspectral approach to be adapted for patient examination to allow the investigation of cartilage state. this could be of advantage for assessment and diagnosis as well as treatment monitoring.

Ruthenium-based sensor detects nitric oxide

8 February 2019:

In a new publication, a responsive Ruthenium-based luminescence sensor was employed as a molecular probe for detecting nitric oxide (NO). The research suggests potential clinical utility for the measurement of soluble NO in the circulation system and possibly tissue. Lead authors of this paper are CNBP’s Dr Achini Vidanapathirana and Benjamin Pullen (both based at SAHMRI).

Journal: Scientific Reports.

Publication title:  A Novel Ruthenium-based Molecular Sensor to Detect Endothelial Nitric Oxide.

Authors: Achini K. Vidanapathirana, Benjamin J. Pullen, Run Zhang, MyNgan Duong, Jarrad M.Goyne, Xiaozhou Zhang, Claudine S. Bonder, Andrew D.Abell, Christina A. Bursill, Stephen J. Nicholls & Peter J. Psaltis.

Abstract: Nitric oxide (NO) is a key regulator of endothelial cell and vascular function. The direct measurement of NO is challenging due to its short half-life, and as such surrogate measurements are typically used to approximate its relative concentrations. Here we demonstrate that ruthenium-based [Ru(bpy)2(dabpy)]2+ is a potent sensor for NO in its irreversible, NO-bound active form, [Ru(bpy)2(T-bpy)]2+. Using spectrophotometry we established the sensor’s ability to detect and measure soluble NO in a concentration-dependent manner in cell-free media. Endothelial cells cultured with acetylcholine or hydrogen peroxide to induce endogenous NO production showed modest increases of 7.3 ± 7.1% and 36.3 ± 25.0% respectively in fluorescence signal from baseline state, while addition of exogenous NO increased their fluorescence by 5.2-fold. The changes in fluorescence signal were proportionate and comparable against conventional NO assays. Rabbit blood samples immediately exposed to [Ru(bpy)2(dabpy)]2+ displayed 8-fold higher mean fluorescence, relative to blood without sensor. Approximately 14% of the observed signal was NO/NO adduct-specific. Optimal readings were obtained when sensor was added to freshly collected blood, remaining stable during subsequent freeze-thaw cycles. Clinical studies are now required to test the utility of [Ru(bpy)2(dabpy)]2+ as a sensor to detect changes in NO from human blood samples in cardiovascular health and disease.