title: Immunophenotyping of blood lymphocytes at birth, during childhood, and during adulthood in HIV-1-uninfected Ethiopians.
abstract: To obtain more insight into blood lymphocyte subpopulations of Ethiopians, we studied the immunologic profile of children and neonates and compared these data with those obtained from adults. Peripheral blood mononuclear cells (PBMCs) and cord blood mononuclear cells (CBMCs) were collected from 137 HIV-1-uninfected subjects aged 0 (cord blood) up to 40 years. Lymphocyte subsets (T, B, and NK cells, CD4+ and CD8+ T cells) were determined and T cell activation (CD38 and HLA-DR) and differentiation (CD45RO and CD27) markers were measured on CD4+ and CD8+ T cells. The absolute number and percentage values of most lymphocyte subpopulations differed substantially with age. Neonates and children were found to have significantly higher CD4+ T cell counts compared to adults. The median absolute CD4 count at birth was comparable to those reported for Caucasians. At birth 97% of the CD4+ T cells were naîve and this proportion significantly declined to 14.2% during adulthood. In addition, activation of both CD4+ and CD8+ T cells, as determined by the double expression of HLA-DR and CD38, was observed in children under the age of 16 and adults, but not in neonates. A more differentiated phenotype (CD27-) was observed in adults compared to children for both CD4+ and CD8+ T cells. The immune alterations including the remarkably low CD4 count with highly depleted naîve phenotype and a persistently activated immune system seen in adult Ethiopians are not apparent at birth, but rather develop over time.
authors.affiliation: Ethio-Netherlands AIDS Research Project, Ethiopian Health and Nutrition Research Institute, PO Box 1242, Addis Ababa, Ethiopia. aster@enarp.com
authors.forename: Aster
authors.initials: A
authors.lastname: Tsegaye
authors.forename: Dawit
authors.initials: D
authors.lastname: Wolday
authors.forename: Sigrid
authors.initials: S
authors.lastname: Otto
authors.forename: Beyene
authors.initials: B
authors.lastname: Petros
authors.forename: Tsehai
authors.initials: T
authors.lastname: Assefa
authors.forename: Tsegaye
authors.initials: T
authors.lastname: Alebachew
authors.forename: Ermias
authors.initials: E
authors.lastname: Hailu
authors.forename: Fekadu
authors.initials: F
authors.lastname: Adugna
authors.forename: Worku
authors.initials: W
authors.lastname: Measho
authors.forename: Wendelien
authors.initials: W
authors.lastname: Dorigo
authors.forename: Arnaud L
authors.initials: AL
authors.lastname: Fontanet
authors.forename: Debbie
authors.initials: D
authors.lastname: van Baarle
authors.forename: Frank
authors.initials: F
authors.lastname: Miedema
mesh_terms: D036541:ADP-ribosyl Cyclase / Q000097:blood; D051997:ADP-ribosyl Cyclase 1; D000293:Adolescent; D000328:Adult; D000375:Aging / Q000097:blood*; D015703:Antigens, CD / Q000097:blood; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D017252:CD3 Complex / Q000097:blood; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D019002:CD56 Antigen / Q000097:blood; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005002:Ethiopia; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000097:blood; D006801:Humans; D016130:Immunophenotyping; D007231:Infant, Newborn; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology*; D007958:Leukocyte Count; D008213:Lymphocyte Activation / Q000276:immunology; D016131:Lymphocyte Subsets / Q000276:immunology*; D008562:Membrane Glycoproteins; D017452:Receptors, IgG / Q000097:blood
chemical_list: D015703:Antigens, CD; D017252:CD3 Complex; D019002:CD56 Antigen; D006684:HLA-DR Antigens; D008562:Membrane Glycoproteins; D017452:Receptors, IgG; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D051997:ADP-ribosyl Cyclase 1