title: Population dynamics of CD4+ T cells lacking Thy-1 in murine retrovirus-induced immunodeficiency syndrome (MAIDS).
abstract: Increased numbers of CD4+ Thy-1- cells have been described in the spleen (SP) of mice with retrovirus-induced immunodeficiency (MAIDS). Since this phenotypic abnormality might have considerable functional importance, the expansion of the CD4+ Thy-1- subset in MAIDS was characterized further. CD4+ Thy-1- and Thy-1+ T-cells from infected mice expressed similar densities of CD3 and TCR alpha/beta. In contrast, the Thy-1- subset was uniformly CD44hi, even early in the disease when part of Thy-1+ cells were still CD44lo. The emergence of CD4+ Thy-1- cells occurred first in SP and lymph nodes and was observed later in thymus. The important fraction of CD4+ cells lacking Thy-1 normally present in Peyer's patches was only weakly modified. Despite the major expansion of the CD4+ Thy-1- phenotype, the proliferating fraction was not higher in this subset than in CD4+ Thy-1+ cells from infected mice. Persistence after hydroxyurea administration was identical in both subsets, indicating similar mean cell lifespans. Taken together, these results show that the major expansion of CD4+ Thy-1- T-cells in MAIDS is not ascribable solely to increased proliferation within this subset. Phenotypic analysis suggests that CD4+ Thy-1- cells result from the differentiation of Thy-1+ cells induced by activation signals related to retroviral infection.
authors.affiliation: Department of Pathology, University of Liège, Belgium.
authors.forename: M P
authors.initials: MP
authors.lastname: Moutschen
authors.forename: S
authors.initials: S
authors.lastname: Colombi
authors.forename: M
authors.initials: M
authors.lastname: Deprez
authors.forename: F
authors.initials: F
authors.lastname: Van Wijk
authors.forename: C
authors.initials: C
authors.lastname: Hotermans
authors.forename: M T
authors.initials: MT
authors.lastname: Martin
authors.forename: R
authors.initials: R
authors.lastname: Greimers
authors.forename: J
authors.initials: J
authors.lastname: Boniver
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D017252:CD3 Complex / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002352:Carrier Proteins / Q000032:analysis; D018960:Hyaluronan Receptors; D007958:Leukocyte Count; D008198:Lymph Nodes / Q000276:immunology; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis; D051379:Mice; D008810:Mice, Inbred C57BL; D016183:Murine Acquired Immunodeficiency Syndrome / Q000276:immunology*; D010641:Phenotype; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D011956:Receptors, Cell Surface / Q000032:analysis; D016201:Receptors, Lymphocyte Homing / Q000032:analysis; D013154:Spleen / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D018800:Thy-1 Antigens
chemical_list: D000954:Antigens, Surface; D017252:CD3 Complex; D002352:Carrier Proteins; D018960:Hyaluronan Receptors; D008562:Membrane Glycoproteins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D011956:Receptors, Cell Surface; D016201:Receptors, Lymphocyte Homing; D018800:Thy-1 Antigens