Researchers: Dr. Adrian Bradu and Dr. Lisha Ma (School of Biosciences)

Supervisors: Prof. A. Podoleanu and Dr. Jim Bloor (School of Biosciences)

Project Funding: BBSRC

Period: November 2006 – November 2009

Project outline

Developmental biology is moving away from standard antibody staining of fixed embryos toward live imaging, which can provide novel insights into various known developmental events. However, live imaging is restricted at the embryo surface. In transparent and semi-transparent organisms amenable to transgenic manipulation the expression of some fluorescent proteins can be detected by laser scanning confocal microscopy. Although by expressing fluorescent proteins one can successfully image transparent areas, effective imaging at depth in embryos and tissue is still restricted. To address this limitation, another imaging technique, such as Optical Coherence Tomography (OCT) needs to be used.

To investigate the potential of OCT based measurement on well characterised and novel animal models for embryology and cell imaging we initiated a collaborative project between the Cell Biology & Developmental Group involving Dr J. Bloor and Dr. Lisha Ma and ourselves.

The aims of the joint research activity were:

  • to develop an OCT platform for high-resolution imaging of cells and embryos, in particular a dual en-face/Doppler OCT instrument capable of recording multiple aspects of heart activity, including heart contraction cycle dynamics, ostia dynamics, heartbeat rate and rhythm, speed of heart wall movement and light reflectivity of cardiomyocytes in situ. We successfully demonstrated the capability of such an instrument by characterizing in detail cardiac activity in genetic models for heart disease in Drosophila melanogaster.
  • to combine the imaging depth capability of OCT with the high lateral resolution of fluorescent imaging by developing a dual OCT-confocal microscope. We demonstrated a combined instrument of the two imaging modalities (Spectral Domain OCT and laser scanning fluorescence microscopy (LSFM)) to acquire information on cardiac function in larval Drosophila melanogaster. Our dedicated imaging instrument is able to sequentially provide cross-sectional OCT and C-scan LSFM images. With this dual-imaging system, the heart can be easily located and visualized within the specimen and the change of the heart shape in a cardiac cycle can be monitored.

Publications

  1. L. Ma, A. Bradu, A. Gh. Podoleanu, J. Bloor, “Arrhythmia Caused by a DrosophilaTropomyosin Mutation Is Revealed Using a Novel Optical Coherence Tomography Instrument”, PLoS ONE 5(12): e14348. doi:10.1371/journal.pone.0014348 (2010);
  2. L.Neagu, A.Bradu, L. Ma, J. Bloor, and Adrian Gh. Podoleanu, “Multiple-depth en face optical coherence tomography using active recirculation loops,” Opt. Lett. 35, 2296-2298 (2010)
  3. A. Bradu, Lisha Ma, J. Bloor and A. Podoleanu, “Dual optical coherence tomography/fluorescence microscopy for monitoring of Drosophila melanogaster larval heart”, J. Biophotonics, Opt., Vol. 2(6-7), p.380-388, 2009;
  4. A. Bradu, L. Ma, J. Bloor, A. Gh.Podoleanu, “Sequential en-face optical coherence tomography imaging and monitoring of Drosophila Melanogaster larval heart” in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XIII, edited by James G. Fujimoto, Joseph A. Izatt, Valery V. Tuchin, Proceedings of SPIE Vol. 7168 (SPIE, Bellingham, WA 2009);
  5. A. Bradu, L. Ma, J. Bloor, A. Gh. Podoleanu, “Using en-face optical coherence tomography to analyse gene function in Drosophila Melanogaster larval heart” in 1st Canterbury Workshop on Optical Coherence Tomography and Adaptive Optics, edited by Adrian Podoleanu, Proceedings of SPIE Vol. 7139 (SPIE, Bellingham, WA 2008);
  6. A. Bradu, L. Ma, J. Bloor, A. Gh. Podoleanu, “Combining confocal microscopy and optical coherence tomography for imaging in developmental biology” in Biophotonics: Photonic Solutions for Better Health Care, edited by Jurgen Popp, Wolfgang Drexler, Valery V. Tuchin, Dennis L. Matthews, Proceedings of SPIE Vol. 6991 (SPIE, Bellingham, WA 2008);
  7. A. Bradu, L. Ma, J. Bloor, A. Gh. Podoleanu, “Versatile confocal/optical coherence tomography system for embryonic developmental imaging” in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XII, edited by Joseph A. Izatt, James G. Fujimoto, Valery V. Tuchin, Proceedings of SPIE Vol. 6847 (SPIE, Bellingham, WA 2008)