Tag Archives: Martin Gosnell

Investigating cell metabolism

Aziz Rehman1 March 2017:

A new publication from CNBP researchers (lead author Aziz Ul Rehman pictured) reports on the application of hyperspectral imaging in combination with fluorescence spectroscopy and chemical quenching to provide a new methodology to investigate cell metabolism.

The work has just been reported in the journal ‘Biomedical Optics Express’ and is accessible online.

Journal: Biomedical Optics Express.

Title: Fluorescence quenching of free and bound NADH in HeLa cells determined by hyperspectral imaging and unmixing of cell autofluorescence.

Authors: Aziz Ul Rehman, Ayad G. Anwer, Martin E. Gosnell, Saabah B. Mahbub, Guozhen Liu, and Ewa M. Goldys.

Abstract: Carbonyl cyanide-p-trifluoro methoxyphenylhydrazone (FCCP) is a well-known mitochondrial uncoupling agent. We examined FCCP-induced fluorescence quenching of reduced nicotinamide adenine dinucleotide / nicotinamide adenine dinucleotide phosphate (NAD(P)H) in solution and in cultured HeLa cells in a wide range of FCCP concentrations from 50 to 1000µM. A non-invasive label-free method of hyperspectral imaging of cell autofluorescence combined with unsupervised unmixing was used to separately isolate the emissions of free and bound NAD(P)H from cell autofluorescence. Hyperspectral image analysis of FCCP-treated HeLa cells confirms that this agent selectively quenches fluorescence of free and bound NAD(P)H in a broad range of concentrations. This is confirmed by the measurements of average NAD/NADH and NADP/NADPH content in cells. FCCP quenching of free NAD(P)H in cells and in solution is found to be similar, but quenching of bound NAD(P)H in cells is attenuated compared to solution quenching possibly due to a contribution from the metabolic and/or antioxidant response in cells. Chemical quenching of NAD(P)H fluorescence by FCCP validates the results of unsupervised unmixing of cell autofluorescence.

Hyperspectral unmixing methodology validated

Aziz Rehman10 February 2017:

A new publication from CNBP researchers Aziz Ul Rehman (pictured), Ayad Anwer, Martin Gosnell, Saabah Mahbub, Guozhen Liu and Ewa Goldys demonstrates the validation of an innovative hyperspectral unmixing methodology, that can derive chemical information from cell colour.

The work has just been reported in the journal ‘Biomedical Optics Express’ and is accessible online.

Journal: Biomedical Optics Express.

Title: Fluorescence quenching of free and bound NADH in HeLa cells determined by hyperspectral imaging and unmixing of cell autofluorescence.

Authors: Aziz Ul Rehman, Ayad G. Anwer, Martin E. Gosnell, Saabah B. Mahbub, Guozhen Liu, and Ewa M. Goldys.

Abstract: Carbonyl cyanide-p-trifluoro methoxyphenylhydrazone (FCCP) is a well-known mitochondrial uncoupling agent. We examined FCCP-induced fluorescence quenching of reduced nicotinamide adenine dinucleotide / nicotinamide adenine dinucleotide phosphate (NAD(P)H) in solution and in cultured HeLa cells in a wide range of FCCP concentrations from 50 to 1000µM. A non-invasive label-free method of hyperspectral imaging of cell autofluorescence combined with unsupervised unmixing was used to separately isolate the emissions of free and bound NAD(P)H from cell autofluorescence. Hyperspectral image analysis of FCCP-treated HeLa cells confirms that this agent selectively quenches fluorescence of free and bound NAD(P)H in a broad range of concentrations. This is confirmed by the measurements of average NAD/NADH and NADP/NADPH content in cells. FCCP quenching of free NAD(P)H in cells and in solution is found to be similar, but quenching of bound NAD(P)H in cells is attenuated compared to solution quenching possibly due to a contribution from the metabolic and/or antioxidant response in cells. Chemical quenching of NAD(P)H fluorescence by FCCP validates the results of unsupervised unmixing of cell autofluorescence.

Cell colour technology wins Eureka prize

OLYMPUS DIGITAL CAMERA31 August 2016:

Ewa Goldys, Deputy Director of the ARC Centre of Excellence for Nanoscale BioPhotonics (CNBP) and Professor at Macquarie University, together with Dr Martin Gosnell, CNBP research affiliate and Managing Director at Quantitative Pty Ltd have won the ANSTO ‘Innovative Use of Technology’ award at the 2016 Australian Museum Eureka Prizes.

They were recognised for their innovative colour focused research, able to distinguish between healthy and diseased cells, in areas as diverse as embryology, neurodegeneration, cancer and diabetes.

“We are absolutely thrilled to be awarded this prize out of such a high-quality field of researchers and scientists,” said Prof Goldys following the Eureka announcement.

“The hyperspectral imaging technique pioneered by our team lets us successfully extract specific biomolecular information hidden in fluorescent colour signatures of living cells and tissues.”

Goldys explained, that with this research, a new window into the body had been opened.

“Through the approach we are taking, incorporating leading-edge microscopes, ‘big data’ and the high processing speeds of modern computers, we are able to noninvasively and rapidly detect major health conditions, across a wide variety of areas.”

The future of the research, Goldys believes is one of high-impact and significant possibility.

“These colour-based cellular and molecular measurements have the potential to be done in-vivo (in the body), expediting the potential for healthcare decisions based on the health needs of the individual and their unique biological characteristics.”

Concluded Goldys, “The really exciting thing is that while we are probing the very limits of our understanding of life at the molecular level, this technology also yields real world translational outcomes – outcomes that will support clinicians in making improved diagnosis and health decisions for patients.”

The Eureka Prizes are presented by the Australian Museum and reward excellence in research and innovation, science communication and journalism, leadership and school science. Prize winners were announced at an Awards Dinner at Sydney Town Hall.

 

Australian Museum Eureka Prizes 2016

Combining computer analysis with microscopy

OLYMPUS DIGITAL CAMERA31 March 2016:

CNBP researchers have successfully combined computer analysis with microscopy, to extract highly detailed cellular information that will help distinguish between healthy and diseased cells, in areas as diverse as cancer, injury and inflammation.

The approach, reported in the journal ‘Scientific Reports’, has shown that subtle biochemical signatures of cells can be captured and then categorized, to an extent that has never been seen before.

Paper Title: Quantitative non-invasive cell characterisation and discrimination based on multispectral autofluorescence features.

Authors: Martin E. Gosnell, Ayad G. Anwer, Saabah B. Mahbub, Sandeep Menon Perinchery, David W. Inglis, Partho P. Adhikary, Jalal A. Jazayeri, Michael A. Cahill, Sonia Saad, Carol A. Pollock, Melanie L. Sutton-McDowall, Jeremy G. Thompson & Ewa M. Goldys.

Abstract: Automated and unbiased methods of non-invasive cell monitoring able to deal with complex biological heterogeneity are fundamentally important for biology and medicine. Label-free cell imaging provides information about endogenous autofluorescent metabolites, enzymes and cofactors in cells. However extracting high content information from autofluorescence imaging has been hitherto impossible. Here, we quantitatively characterise cell populations in different tissue types, live or fixed, by using novel image processing and a simple multispectral upgrade of a wide-field fluorescence microscope. Our optimal discrimination approach enables statistical hypothesis testing and intuitive visualisations where previously undetectable differences become clearly apparent. Label-free classifications are validated by the analysis of Classification Determinant (CD) antigen expression. The versatility of our method is illustrated by detecting genetic mutations in cancer, non-invasive monitoring of CD90 expression, label-free tracking of stem cell differentiation, identifying stem cell subpopulations with varying functional characteristics, tissue diagnostics in diabetes, and assessing the condition of preimplantation embryos.

The research paper is accessible online. A CNBP media release is also available.