Normal thymic cortical epithelial cells developmentally regulate the expression of a B-lineage transformation-associated antigen.
Nonlymphoid, stromal cells in the mouse thymus are believed to be important in T cell maturation and have been proposed to play a central role in the acquisition of major histocompatibility complex (MHC) restriction and self-tolerance by maturing thymocytes. Both cortical and medullary epithelial cells in the thymus express high levels of class II (A) major histocompatibility antigens (MHC Ags). We show here that a specific subset of these A+ epithelial cells express a transformation-associated antigen (6C3Ag) found previously on the surfaces of Abelson murine leukemia virus-transformed pre-B cells and on those bone marrow-derived stromal cell clones which support normal and preneoplastic pre-B cell proliferation. Among solid lymphoid organs, only the thymus contains 6C3Ag+ cells and within the thymus, this antigen is found exclusively on A+ epithelial cells in cortical regions. It is striking that the expression of the 6C3Ag on thymic epithelium is developmentally regulated, suggesting a role for this lymphostromal antigen in the maturation of the thymic microenvironment.
Adkins
B
B
Department of Pathology, Stanford University School of Medicine, CA 94305.
Tidmarsh
G F
GF
Weissman
I L
IL
D000011:Abelson murine leukemia virus; D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis*; D001402:B-Lymphocytes / Q000032:analysis / Q000276:immunology*; D001853:Bone Marrow / Q000032:analysis / Q000276:immunology; D002454:Cell Differentiation; D002472:Cell Transformation, Viral; D005314:Embryonic and Fetal Development; D004847:Epithelial Cells; D004848:Epithelium / Q000032:analysis / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D013234:Stem Cells / Q000032:analysis / Q000276:immunology; D013950:Thymus Gland / Q000032:analysis / Q000166:cytology / Q000276:immunology*
D000944:Antigens, Differentiation, B-Lymphocyte; D000949:Histocompatibility Antigens Class II