par Van Eycke, Yves-Remi ;Moles Lopez, Xavier ;Allard, Justine;Derock, Mélanie ;Rorive, Sandrine ;Salmon, Isabelle ;Decaestecker, Christine
Référence Digital Pathology Congress(4-5 December 2014: London), Digital Pathology Congress, Poster Presentation Abstracts, Global Engage, page (15)
Publication Publié, 2014-12
Abstract de conférence
Résumé : Extracting relevant information from actors involved in complex biological processes (such as cancers or treatment responses) requires to target different antigens simultaneously. Multichromogenic (brightfield) immunohistochemistry (IHC) suffers from limitations that notably prevent the analysis of proteins expressed in the same cellular compartment. We thus developed an alternative based on the analysis of adjacent, or serial, tissue sections on which different proteins were targeted by means of standard IHC. For this analysis, we developed a multiresolution method for registering serial slide images. This method uses the pyramidal and multimodal registration framework of the elastix software to optimize two parametric registrations. The first, low-resolution registration, is applied on the 1X equivalent magnification images (4,000 by 3,000 pixels). The result of this first step was then used to initialize high-resolution registrations independently performed on 20X equivalent fields of view. Our method shows accuracy levels compatible with biomarker colocalization characterization. Indeed, registration error on serial slides was evaluated to be at most between 20 µm and 80 µm, depending respectively of the presence or absence of histological structures in the tissue (e.g. in colonic tumor as compared to brain gliomas). In the latter situation, a sequential IHC technique applied on the same slide can be usefully employed. This “Sequential Immunoperoxidase Labeling and Erasing” (SIMPLE) method is based on cycles of staining/digitization/erasing, where after IHC staining and slide digitization, staining is erased through an antibody elution technique. We improved the original SIMPLE method and successfully utilized it to identify antigens expressed in the same cellular compartment of high-grade glioma samples. We tested our registration on the virtual slides so obtained and achieved very good results, i.e. about 5 µm of registration error. We then implemented a method to extract biomarker colocalization measurements taking the level of registration error into account and validated our complete procedure by comparison to colocalization information obtained by means of double staining (with different cell locations).