title: Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood.
abstract: Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009), which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.
authors.affiliation: Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Maria Isabel de
authors.initials: MI
authors.lastname: Moraes-Pinto
authors.affiliation: Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Erika
authors.initials: E
authors.lastname: Ono
authors.affiliation: Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Elisângela C
authors.initials: EC
authors.lastname: Santos-Valente
authors.affiliation: Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Liziane C
authors.initials: LC
authors.lastname: Almeida
authors.affiliation: Centro Assistencial Cruz de Malta, São Paulo, SP, Brasil.
authors.forename: Paula Rosemberg de
authors.initials: PR
authors.lastname: Andrade
authors.affiliation: Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Maria Isabel Saraiva
authors.initials: MI
authors.lastname: Dinelli
authors.affiliation: Departamento de Pediatria, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Amélia M Nunes dos
authors.initials: AM
authors.lastname: Santos
authors.affiliation: Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: Reinaldo
authors.initials: R
authors.lastname: Salomão
mesh_terms: D051997:ADP-ribosyl Cyclase 1; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001402:B-Lymphocytes / Q000166:cytology; D001938:Brazil; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology*; D002648:Child; D002675:Child, Preschool; D002986:Clinical Trials as Topic; D003430:Cross-Sectional Studies; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D064368:Healthy Volunteers; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007694:Killer Cells, Natural / Q000166:cytology; D017493:Leukocyte Common Antigens; D007963:Leukocytes, Mononuclear / Q000166:cytology; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D055815:Young Adult
chemical_list: D017493:Leukocyte Common Antigens; D051997:ADP-ribosyl Cyclase 1