title: Ly-5.185 molecule is associated with thymic maturation of lymphocytes but not with their cytotoxic activity.
abstract: The Ly-5 system is a composite family of molecules with different molecular weight. Each molecular form is characteristic of a different lymphoid population, in particular a 175,000- to 185,000-dalton doublet is peculiar of thymocytes and peripheral T cells. Athymic nude mice, however, lack the 185,000-dalton form on their lymphocytes. To investigate whether the expression of the 185,000 daltons requires the presence of thymus, we induced nude mice lymphocytes to differentiate into mature T cells in vivo by thymus grafting and, in vitro, into T cytotoxic cells (CTL) by cocultivation with alloantigen plus recombinant interleukin 2 (IL-2). The appearance of the 185,000-dalton form on lymphocytes of thymus-grafted nude mice but not on in vitro activated cytotoxic cells indicates an active role of thymus in the induction of this molecule and suggests that 185,000-dalton form could be a marker of intrathymic differentiation but not of the cytotoxic activity of T cells.
authors.affiliation: Divisions of Experimental Oncology D, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Traversari
authors.forename: G
authors.initials: G
authors.lastname: Ferrari
authors.forename: L
authors.initials: L
authors.lastname: Grazioli
authors.forename: D
authors.initials: D
authors.lastname: Ballinari
authors.forename: M P
authors.initials: MP
authors.lastname: Colombo
authors.forename: C
authors.initials: C
authors.lastname: Castelli
authors.forename: M A
authors.initials: MA
authors.lastname: Pierotti
authors.forename: G
authors.initials: G
authors.lastname: Parmiani
mesh_terms: D000818:Animals; D000943:Antigens, Differentiation / Q000276:immunology*; D000950:Antigens, Ly / Q000276:immunology*; D015415:Biomarkers; D006649:Histocompatibility Antigens / Q000276:immunology*; D007376:Interleukin-2 / Q000502:physiology; D017493:Leukocyte Common Antigens; D051379:Mice; D008819:Mice, Nude; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013950:Thymus Gland / Q000254:growth & development / Q000502:physiology* / Q000637:transplantation
chemical_list: D000943:Antigens, Differentiation; D000950:Antigens, Ly; D015415:Biomarkers; D006649:Histocompatibility Antigens; D007376:Interleukin-2; D017493:Leukocyte Common Antigens