TY - CHAP SN - 978-84-614-6191-2 AU - Grossmann, C. AU - Schwarz-Finsterle, Jutta AU - Schmitt, Eberhard AU - Birk, Udo AU - Hildenbrand, Georg AU - Cremer, Christoph AU - Trakhtenbrot, Luba AU - Hausmann, Michael T1 - Variations of the spatial fluorescence distribution in ABL gene chromatin domains measured in blood cell nuclei by SMI microscopy after COMBO – FISH labelling T2 - Microscopy. Science, technology, applications and education ED - Méndez-Vilas, Antonio ED - Díaz, J. PY - 2010 CY - Badajoz PB - Formatex SV - 4 SP - 688 EP - 695 T3 - Formatex Microscopy Series AB - Despite investigations of the nuclear architecture of the genome, the true 3D nanoarchitecture of small chromatin domains and its correlation to epigenetic control mechanisms are still not sufficiently known. Reasons for this are the lack of nanostructure conserving labelling techniques as well as practical limitations in 3D fluorescence microscopy with high optical resolution (100 nm and below). The present study was initiated as an attempt to overcome these methodological shortcomings. As a model case we compared the spatial extension of fluorescence of chromatin domains in ABL gene regions in blood cells (BC) of different Chronic Myelogenous Leukemia (CML) patients with BCR/ABL fusion on the Philadelphia chromosome (Ph) and in lymphocytes of a healthy donor and a Prader-Willi syndrome patient by Spatially Modulated Illumination (SMI) microscopy after specific labelling using COMBinatorial Oligo Fluorescence In Situ Hybridization (COMBO–FISH). Volumes and compaction ratios of interactively identified ABL chromatin domains were determined under the assumption of a compact spherical fluorescence distribution. Significant differences were found between the domain size values of the labelled sites of Ph+ BC nuclei of CML patients and of Ph- BC nuclei of a CML patient after successful chemotherapy (imatinib mesylate (STI) treatment). Differences were also significant between BC of all CML patients and lymphocyte control preparations. These results show the feasibility of COMBO-FISH in combination with SMI microscopy. M4 - Citavi ER -