Mouse CD24 is required for homeostatic cell renewal.
Under physiological conditions, some adult tissues retain a capacity for self-renewal. This property is attributable to the proliferation and differentiation of stem, transit-amplifying, and differentiating cells, which are regulated by cell-cell or cell-matrix interactions or by secreted factors. By gain and loss of function experiments, we demonstrate the involvement of mouse CD24 (mouse cluster of differentiation 24), which is a glycosyl phosphatidylinositol (GPI)-anchored cell-surface glycoprotein, in the regulation of homeostatic cell renewal. BrdU incorporation observations, at optical and electron-microscopic levels, have revealed increased cell proliferation in the developing brain and in the epithelia of mCD24-deleted mice. We have observed ectopic proliferative cells in the suprabasal layers of the mutant skin leading to a general disruption of basal and suprabasal layers. By contrast, ectopic mCD24 expression mediated by retroviral infection of the embryonic brain leads to a decreased number of clusters of cells generated in the progeny. Together, these results and our previous published data indicate that mCD24 contributes to the regulation of the production of differentiated cells by controlling the proliferation/differentiation balance between transit-amplifying and committed differentiated cells.
Nieoullon
Vincent
V
Institut de Biologie du Développement de Marseille Luminy, UMR 6216 Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Campus de Luminy, 13288 Marseille, France.
Belvindrah
Richard
R
Rougon
Geneviève
G
Chazal
Geneviève
G
D000818:Animals; D001921:Brain / Q000166:cytology / Q000196:embryology; D001973:Bromodeoxyuridine; D051927:CD24 Antigen / Q000302:isolation & purification / Q000502:physiology*; D049109:Cell Proliferation; D019573:Epithelium, Corneal / Q000166:cytology / Q000648:ultrastructure; D006706:Homeostasis; D051379:Mice; D008810:Mice, Inbred C57BL; D046529:Microscopy, Electron, Transmission; D051381:Rats; D012038:Regeneration / Q000502:physiology*; D012867:Skin / Q000166:cytology / Q000648:ultrastructure
D051927:CD24 Antigen; D001973:Bromodeoxyuridine