title: Progressive increase of CD7- T cells in human blood lymphocytes with ageing.
abstract: CD7 is one of the major surface antigens expressed very early during T cell ontogeny. Lack of CD7 expression on mature T cells is regarded as a classical feature of malignant T cells in certain forms of cutaneous T cell lymphoma. Previously, we identified a CD7- subset of peripheral blood T lymphocytes in normal human individuals. In this study we determined the portion of CD7- T cells in the peripheral blood of healthy volunteers ranging in age from 8 months to 90 years (n = 85) and in cord blood of full-term infants (n = 14). Furthermore, this CD7- subset was characterized in detail by the use of MoAbs and three-colour flow cytometry. In cord blood no CD7- T cells could be detected. After birth, percentage and absolute number of CD7- T cells increased with age. Independently of age, most CD7-CD3+ cells belonged to the CD4+ subpopulation. Focusing on the latter we could demonstrate the predominance of the CD45RO+CD45RA- phenotype in the CD7- subset. Furthermore, CD7- T cells contained a higher number of cells expressing activation markers and the CD57 antigen, but a reduced number of CD62L+ cells in comparison with CD7+ T cells.
authors.affiliation: Department of Dermatology, University of Bonn, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Kukel
authors.forename: U
authors.initials: U
authors.lastname: Reinhold
authors.forename: I
authors.initials: I
authors.lastname: Oltermann
authors.forename: H W
authors.initials: HW
authors.lastname: Kreysel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D015703:Antigens, CD / Q000097:blood*; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte / Q000097:blood*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006684:HLA-DR Antigens / Q000097:blood; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D017493:Leukocyte Common Antigens / Q000097:blood; D008297:Male; D008875:Middle Aged; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D019011:Antigens, CD7; D000945:Antigens, Differentiation, T-Lymphocyte; D006684:HLA-DR Antigens; D017493:Leukocyte Common Antigens