Applied Imaging and Researchers at Sanger Institute partner to develop automated, high throughput method of fluorescent TMA analysis using Ariol™ system

Applied Imaging and researchers at the Wellcome Trust Sanger Institute in Cambridge have used an Applied Imaging Ariol™ imaging system to develop one of the first automated processes for high-throughput image capture and analysis of fluorescent tissue microarrays (TMAs).

Developed in collaboration between the two organisations, this breakthrough method is based on a pre-scan routine that allows the user to set optimal illumination levels for each TMA core examined. This subsequently allows for the capture and quantitative analysis of images at a resolution of <0.5 microns per pixel. The resultant images can then be annotated with sub-cellular localisation and expression profile data and exported to the underlying ATLAS image database. The development of the TMA pre-scan routine follows an initial collaborative research programme undertaken by the two organisations in the field of high throughput image capture and analysis of chromagen stained TMAs and tissue sections using AI’s Ariol™ software.

Led by Dr. John McCafferty, the ATLAS group aims to create an information-rich database of protein expression profiles using recombinant antibodies from phage display technology in immunohistochemistry studies. An important component of this has been the use of the Ariol™ system for the automated examination of TMAs, carrying out frame-by-frame imaging of slides and tissues in a high-throughput manner.

As Dr. William Howat, leader of the collaboration at Sanger explains, “One of the primary difficulties encountered with fluorescent TMA slides has been the fact that varying levels of fluorescence are often produced within the same slide. This complicates the process of trying to balance the illumination and exposure levels needed to generate meaningful images. If the images are over-exposed, the details of the specimen become hard to distinguish and subtle staining variation is lost. If under-exposed the image becomes too dim and false-negatives may occur. Based on our novel pre-scan routine, carried out either at 5x or 10x, the user can determine multiple exposures for each of the TMA cores on a slide and thus ensure the generation of crisp, reliable images that are then automatically ascribed quantitative region scores [percent positive vs. percent negative]. These can then be annotated for inclusion into the ATLAS project. Given the size of the task at hand, the capability to generate such information from an automated platform is proving to be of great value to our group.”

Mark Gregson, VP of Product Development at Applied Imaging added, “We’re very pleased to be working with the Sanger Institute and to have taken our partnership through to the next stage. The development of a reliable, automated and high-throughput method of examining fluorescent TMAs is not only of importance to the Atlas project but to all those researchers working with such sample types. Importantly, this will significantly reduce the time required for pathologists to be working on TMA analysis and allow them to better allocate their resources.”

Early samples of images taken by the Ariol system for the Atlas of Protein Expression project can be viewed at: www.sanger.ac.uk/Teams/Team86