Editorial – encouraging collaboration in optical diagnosis

Welcome to this themed issue on the topic of Optical Diagnosis.

This collection of articles is a continuation of a themed issue published in 2009 on this same topic. The success of the first issue was largely due to gathering articles together from a range of presentations given on this topic at two conferences in the area, ICORS and SPEC. This issue again features research which was presented and discussed at the SPEC 2010 Conference, Shedding Light on Disease: Optical Diagnosis for the New Millennium, which was held at the University of Manchester in June and July of this year.

This themed issue contains 2 communications and 32 papers on the topic of optical spectroscopy for the diagnosis of disease. It aims to build on the work presented in the previous issue, to highlight the most recent advances and demonstrate how the field has developed in the intervening two years. SPEC 2010 this year also featured a strong focus on the clinical application of these technologies, with the message for those developing the technologies in the lab, to consider how these relate to applications in the clinic. There was a desire to work more closely with practitioners to achieve workable solutions. As a community it is clear to see that this is message is beginning to sink in, and is already working very successfully in some cases. It is exciting to think of the developments that might be achieved by SPEC 2012 through closer involvement of the physical scientists with clinicians.

Once again the articles in the issue can be viewed as three different themes. The first of which is a focus on the specific diseases where improved diagnosis is being investigated using optical spectroscopies. The second is the use of optical spectroscopies for cell and tissue analysis relating to the diagnosis, understanding the nature and treatment of disease, and lastly technical improvements in the techniques involved.

As with the issue published in 2009, there is a strong focus on the techniques used for the detection and diagnosis of cancer. Stone and colleagues discuss the use of a Raman probe for oesophageal cancer diagnostics. Horsnell and colleagues demonstrate an exciting new method for intra-operative assessment of axillary lymph nodes. Goormaghtigh et al. have examined prostate cancer cells using FTIR, Wehbe and co-workers have also used FTIR imaging to differentiate between normal and tumor vasculature of animal and human glioma. The detection and effectiveness of cancer drugs is examined by Byrne and colleagues who evaluate the potential of Raman microspectroscopy for prediction of chemotherapeutic response to cisplatin in lung adenocarcinoma, and Bellisola et al. use FTIR microspectroscopy for tracking the signatures of drugs in cancer cells. Lyng et al. use vibrational spectroscopy for examining the influence of high-risk human papillomavirus on the biochemical composition of cervical cancer cells, and Severcan et al. characterize microRNA-125b expression in MCF7 breast cancer cells by ATR-FTIR spectroscopy.

Other diseases which are also examined in this issue include measles, as Dluhy and colleagues use SERS for the identification of individual genotypes of the measles virus, together with diabetes, which Severcan and colleagues investigate in rat muscle by FTIR spectroscopy.

The second theme is the use of optical spectroscopies for cell and tissue analysis, and clearly an emerging area is that of stem cell analysis. This features strongly in the themed issue with an article from Diem et al. on the confocal Raman microspectral imaging (CRMI) of murine stem cell colonies. Evidence for a stem-cell lineage in corneal squamous cell carcinoma using synchrotron-based FTIR microspectroscopy is presented by Martin et al., vibrational spectroscopy is used to differentiate between multipotent and pluripotent stem cells by Sulé-Suso et al., and Gardner and colleagues use SR-FTIR spectroscopy for examining renal epithelial carcinoma side population cells, which display stem cell-like characteristics.

Optical spectroscopies are also being applied to a variety of different cell and tissue types, including Raman spectroscopy for the evaluation of bone tissue by Morris et al. Isaksson et al. also use cluster analysis to examine infrared spectra of rabbit cortical bone samples during maturation and growth.

Huang and colleagues present differentiation between benign and malignant ulcers in the stomach. Live cells are examined on a three dimensional collagen matrix using Raman microspectroscopy by Lyng and Byrne et al., and Popp, Krafft and co-workers explore the detection and identification of circulating tumour cells using Raman spectroscopy. Khaustova and co-workers use FTIR of saliva for the noninvasive biochemical monitoring of physiological stress. Sergo and colleagues use Raman mapping for the chemical imaging of articular cartilage sections, and Notingher and colleagues use Raman micro-spectroscopy for the label-free molecular imaging of immunological synapses between dendritic and T cells.

The third area is the advancements in the technologies that are being used. These include an article on time-resolved spatially offset Raman spectroscopy for depth analysis of diffusely scattering layers by Ariese et al. A tunable external cavity quantum cascade laser has been developed for the simultaneous determination of glucose and lactate by Lendl and colleagues. Martin and colleagues have developed a SHE assay coupled with infrared spectroscopy and chemometrics for toxicological assessment.

It is clear from the developments in the last two years that the area of optical diagnosis for the detection of disease will continue to develop at an exciting pace, and is already having an impact on the future diagnosis and hence treatment of many. We hope that you will enjoy reading the latest developments reported in this issue, and that it will stimulate many more to come.

May Copsey

Editor, Analyst

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