title: Immunohistochemical localization of host and donor-derived cells in the regenerating thymus of radiation bone marrow chimeras.
abstract: The anatomical distribution of CBA (Thy-1.2) host and AKR (Thy-1.1) donor-derived cells in the regenerating thymus of AKR----CBA radiation bone marrow chimeras was investigated. Cryostat sections of chimeric thymuses were incubated with biotin-conjugated monoclonal anti-Thy-1 antibodies specific for host and donor-derived cells and the distribution of the corresponding Thy-1 antigen revealed by the immunoperoxidase staining technique. The thymus was initially repopulated by Thy-1.2+ host-derived cells, but by 28 days following bone marrow reconstitution the few remaining host cells were found mostly in the thymus medulla. However, occasional Thy-1.2+ cells were still present in extramedullary, primarily cortical, sites. Donor-derived (Thy-1.1+) cells were first seen in the 11-day chimeric thymus as single cells frequently closely associated with blood vessels in medullary areas. By 17 days, the cortex contained many Thy-1.1+ cells, although occasional single positive cells were still present in the medulla. Changes in the anatomical distribution of host and donor-derived cells in the regenerating chimeric thymus appeared to correlate with changes in their Thy-1 fluorescence profile as determined by flow microfluorometry.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001853:Bone Marrow / Q000528:radiation effects*; D016026:Bone Marrow Transplantation; D005434:Flow Cytometry; D006651:Histocytochemistry; D006801:Humans; D007120:Immunochemistry; D007124:Immunoenzyme Techniques; D051379:Mice; D008806:Mice, Inbred AKR; D008808:Mice, Inbred CBA; D011828:Radiation Chimera; D012038:Regeneration; D013950:Thymus Gland / Q000166:cytology* / Q000502:physiology; D014019:Tissue Donors
chemical_list: D000911:Antibodies, Monoclonal