Unit: Dynamic Imaging (Platform)
Director: Spencer L. Shorte
The plate-forme d'imagerie dynamique (PFID) is an applied-sciences group at the Pasteur Institute. Our research is multi-disciplined and collaborative, focussed precisely on developing and implementing cutting-edge methods and technologies using dynamic-imaging to understand the processes of cell/tissue-biology and their usurpation by infection and disease.
In basic, and pre-clinical biological sciences the term Dynamic Imaging has come to refer to a diverse array of key-technologies that employ the properties of light (particularly fluorescence and bioluminescence) to probe molecular and cellular biology. In this context, the state-of-the-art is defined by paradigms using so-called multi-dimensional (multi-D) dynamic imaging microscopy. Multi-D imaging aims to visualize and quantify biological events through time and space, and more specifically refers to combinations of: three (3D, volume), four (4D, time), and five (5D, multi-wavelength) dimensional recordings. The PFID is especially interested in the development of multi-D imaging techniques and their application to cellular microbiology.
The PFID currently has three main goals to its R&D programmes:
DEVELOPMENT AND APPLICATION OF NEW MOLECULAR PROBES- Multi-D imaging depends upon the use of molecules that yield light signals that may be detected and thereby give information concerning the biology under study. There already exist an enormous variety of inorganic, and organic light emitting probes that may be targeted by virtue of their (bio)-chemical and/or molecular specificity. However, the requisite for adaptation of existing probes, and development of new probes is never-ending in the face of new questions and the growing complexity of the processes to be measured. The PFID is therefore committed to development of new molecular probes, and new applications of existing probes.
DEVELOPMENT OF NOVEL IMAGING MODALITIES- Multi-D imaging requires complex and sophisticated hardware enabling light emitted from samples under study to be recorded in multiple dimensions. To-date these imaging modalities are somewhat restrictive with regard to the types of sample that may be studied, due mainly to limitations of spatial and temporal resolution. In particular, they are highly dependent upon speed and sensitivity of detection devices, and our ability to automate high-speed acquisition coordinately using mechanical devices. In light of these restrictions the PFID is fully engaged in programs aimed to develop new multi-D imaging modalities, and implementation of state-of-the-art high-speed detection devices.
DEVELOPMENT OF SIGNAL PROCESSING SOLUTIONS- Multi-D imaging is highly dependent upon the use of signal-processing algorithms and software that allow quantitative: a) image-enhancement, b) image-reconstruction, and c) image-analysis. Ideally, signal-processing applications allow batch-handling of datasets with minimal user intervention, in a semi-automated manner, which is simple to apply and reproducible. The PFID is currently engaged in development of informatics utilities, aimed to help simplify the process of image treatment and analysis; and the development of new signal processing solutions arising from novel imaging modalities.
SELECTED WORK IN-PROGRESS 2003:
Development of novel labeling strategies to produce infection competent fluorescent viruses (collaborators: N.Arhel, P.Charneau).
Characterization of fluorescent probes allowing actin polymerization to be measured in situ (collaborators: S.Munter, U.Nehrbass).
Development of method and device allowing super-high resolution, three-dimensional reconstruction from fluorescent signals inside individual non-adherent living cells (collaborators: B.Chalmond & Evotec-Technologies).
Development of informatics utilities for image-acquisition and -analysis.
Development of remote protocols and methods for piloting imaging systems at a distance, especially those placed in P3 level laboratories (collaborators: L.Chakrabarti).
Development of bioluminescence imaging methods for probing infection and physiology in situ (collaborators: O.Dussurget, P.Cossart, P.Sansonetti, G.Milon, M.Brahic, K.Rogers, P.Brulet)
Keywords: cell biology, infection, dynamic imaging, image analysis, image reconstruction