title: Phase-contrast zoom tomography reveals precise locations of macrophages in mouse lungs.
abstract: We have performed x-ray phase-contrast tomography on mouse lung tissue. Using a divergent x-ray beam generated by nanoscale focusing, we used zoom tomography to produce three-dimensional reconstructions with selectable magnification, resolution, and field of view. Thus, macroscopic tissue samples extending over several mm can be studied in sub-cellular-level structural detail. The zoom capability and, in particular, the high dose efficiency are enabled by the near-perfect exit wavefront of an optimized x-ray waveguide channel. In combination with suitable phase-retrieval algorithms, challenging radiation-sensitive and low-contrast samples can be reconstructed with minimal artefacts. The dose efficiency of the method is demonstrated by the reconstruction of living macrophages both with and without phagocytized contrast agents. We also used zoom tomography to visualize barium-labelled macrophages in the context of morphological structures in asthmatic and healthy mouse lung tissue one day after intratracheal application. The three-dimensional reconstructions showed that the macrophages predominantly localized to the alveoli, but they were also found in bronchial walls, indicating that these cells might be able to migrate from the lumen of the bronchi through the epithelium.
authors.affiliation: Institute for X-ray Physics, University of Göttingen, 37077 Göttingen, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Krenkel
authors.affiliation: Department of Haematology and Medical Oncology, University Medical Center Göttingen, 37075 Göttingen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Markus
authors.affiliation: Institute for X-ray Physics, University of Göttingen, 37077 Göttingen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Bartels
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Medical Center Göttingen, 37075 Göttingen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Dullin
authors.affiliation: 1] Department of Haematology and Medical Oncology, University Medical Center Göttingen, 37075 Göttingen, Germany [2] Department of Diagnostic and Interventional Radiology, University Medical Center Göttingen, 37075 Göttingen, Germany [3] Department of Molecular Biology of Neuronal Signals, Max-Planck-Institute of Experimental Medicine, 37077 Göttingen, Germany.
authors.forename: Frauke
authors.initials: F
authors.lastname: Alves
authors.affiliation: Institute for X-ray Physics, University of Göttingen, 37077 Göttingen, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Salditt
mesh_terms: D000818:Animals; D002461:Cell Line, Transformed; D002465:Cell Movement / Q000502:physiology*; D016676:Macrophages, Alveolar / Q000000981:diagnostic imaging / Q000502:physiology; D051379:Mice; D011650:Pulmonary Alveoli / Q000000981:diagnostic imaging / Q000502:physiology; D020545:Respiratory Mucosa / Q000000981:diagnostic imaging / Q000502:physiology; D014056:Tomography, X-Ray / Q000379:methods*