Evaluation of disease models is facilitated by live imaging which can be used to follow the behavior of the model during disease evolution, and when comparing before and after therapeutic intervention. When exploring in vitro samples for disease modeling in culture, there is a need for live, 3D, non invasive, real time, label free, subcellular resolution, dynamic, longitudinal imaging, which is currently lacking from the microscopy toolkit. Dynamic full field optical coherence tomography meets these needs and shows promise as a next generation tool for 3D live microscopy. Full-field optical coherence tomography is an interferometric technique to image transverse planes inside a sample in one shot, thus allowing distortionless rapid en face and volumetric imaging. Dynamic full field OCT is an evolution of full field OCT, where a series of frames is collected by the camera and the contrast generated by natural movements of subcellular organelles within the sample is revealed. Here, we present a new dynamic full field OCT module that may be interfaced to commercial microscopes, designed for use by biologists for long term applications in culture conditions. We present its application to models of disease in 2D and 3D samples.

A low-powered, non-invasive digital holographic microscopic imaging technique for embryo quality assessment is presented. Two groups of 2 cell-stage embryos cultured in media of different lipid concentrations have been characterized with digital holographic microscopy for lipid aggregation. The study suggests refractive index measurements are reflective of the lipid and dry mass content in embryos thus making DHM a prospective label-free diagnostic tool for quality assessments in assisted reproduction.

It has recently been discovered that biological live cells can behave like optical microlenses.

This has opened a new path towards future disruptive scenarios with the possibility of using such biolenses for the next technological developments in optics and photonics. Live cells can be employed and exploited as optical components for incredible applications ranging from simple imaging, to soft matter manipulation and biomedical diagnosis. In fact, the optical properties of such biological lenses can reveal new biomarkers useful for medical diagnosis. Different examples of application of biolenses will be illustrated and discussed. Furthermore, a new perspective for engineering biolenses to tailor their photonic properties will also be presented. Furthermore, it will be demonstrated that in-flow staining-free cytotomography based on digital holography allows for a complete and accurate 3D characterization of biolenses.

Whether host phenotypic alterations induced by parasites are reversible or not is a core issue to understand underlying mechanisms as well as the fitness costs of infection and recovery to the host. Clearing infection is an essential step to address this issue, which turns out to be challenging with endoparasites of large size relative to that of their host. Here, we took advantage of the lethality, contactless and versatility of high-energy laser beam to design such tool, using thorny-headed worms and their amphipod intermediate host as a model system. We show that laser-based de-parasitization can be achieved using blue laser targeting carotenoid pigments in Polymorphus minutus but not in the larger and less pigmented Pomphorhynchus tereticollis. Using DNA degradation to establish parasite death, we found that 80% P. minutus died from within-host laser exposure. Survival rate of infected gammarids to laser treatment was higher than uninfected ones. The failure to kill P. tereticollis was also observed with nanosecond-green laser, an alternative laser source targeting lipid. We discuss the possible causes of amphipod death following parasite treatment and highlight the perspectives that this technology offers.