Immunophenotyping of blood lymphocytes at birth, during childhood, and during adulthood in HIV-1-uninfected Ethiopians.
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.
Tsegaye
Aster
A
Ethio-Netherlands AIDS Research Project, Ethiopian Health and Nutrition Research Institute, PO Box 1242, Addis Ababa, Ethiopia. aster@enarp.com
Wolday
Dawit
D
Otto
Sigrid
S
Petros
Beyene
B
Assefa
Tsehai
T
Alebachew
Tsegaye
T
Hailu
Ermias
E
Adugna
Fekadu
F
Measho
Worku
W
Dorigo
Wendelien
W
Fontanet
Arnaud L
AL
van Baarle
Debbie
D
Miedema
Frank
F
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
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