Metallophilic macrophages are lacking in the thymus of lymphotoxin-beta receptor-deficient mice.
Lymphotoxin-beta receptor (LTbetaR) axis plays a crucial role in development and compartmentalization of peripheral lymphatic organs. But, it is also required for the appropriate function and maintenance of structural integrity of the thymus: in LTbetaR-deficient animals the clonal deletion of autoreactive lymphocytes is impaired and differentiation of thymic medullary epithelial cells is disturbed. In this study, using several markers, we showed that thymic metallophilic macrophages were lacking in LTbetaR-deficient mice. In tumor necrosis factor receptor-I (p55)-deficient mice (which we used as positive control) thymic metallophilic cells were located, similarly as in normal mice, in the thymic cortico-medullary zone at the junction of cortex and medulla. These findings show that LTbetaR is necessary for maintenance of metallophilic macrophages in the thymus and provide further evidence that these cells may represent a factor involved in thymic negative selection.
Milićević
Novica M
NM
Institute of Histology and Embryology, University of Belgrade Medical School, Visegradska 26, 11000 Belgrade, Serbia and Montenegro. emilicen@etf.bg.ac.yu
Nohroudi
Klaus
K
Labudović-Borović
Milica
M
Milićević
Zivana
Z
Pfeffer
Klaus
K
Westermann
Jürgen
J
D000818:Animals; D053259:Lymphotoxin beta Receptor / Q000172:deficiency* / Q000276:immunology*; D053308:Lymphotoxin-beta; D008264:Macrophages / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000172:deficiency / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology*
D053259:Lymphotoxin beta Receptor; D053308:Lymphotoxin-beta; D047888:Receptors, Tumor Necrosis Factor, Type I