title: Lymphocyte subpopulation number and function in infancy.
abstract: Normal values for percentages of lymphocyte subpopulations and functional responses to mitogen stimulation in infancy are not well established. In the present study, lymphocyte subpopulations were examined in umbilical cord blood samples and in peripheral blood samples drawn before 7 and 24 months of age (mean age 10.4 months) from a healthy population of infants born in Tucson, Arizona. Results indicate significant increases occurred from birth to later infancy in the percentages of total T cells (CD3), T-cell subsets (CD4, CD8) and B cells (CD20). The CD4/CD8 ratio and the functional responses to ConA and PWM mitogens significantly decreased from birth to later infancy. PHA responsiveness did not show a significant change. Results from cross-sectional analyses (n = 271) were supported in a smaller longitudinal subset (n = 37). There were no detectable ethnic- or gender-related differences in cord blood or samples obtained in later infancy. The normal values established in this study will be useful in studies of immune-system maturation and in the clinical evaluation of newborns, infants, and toddlers suspected of either acquired or congenital immune-deficiency states.
authors.affiliation: Respiratory Sciences Center, University of Arizona Health Sciences Center, Tucson 85724.
authors.forename: D A
authors.initials: DA
authors.lastname: Stern
authors.forename: M J
authors.initials: MJ
authors.lastname: Hicks
authors.forename: F D
authors.initials: FD
authors.lastname: Martinez
authors.forename: C J
authors.initials: CJ
authors.lastname: Holberg
authors.forename: A L
authors.initials: AL
authors.lastname: Wright
authors.forename: J
authors.initials: J
authors.lastname: Pinnas
authors.forename: M
authors.initials: M
authors.lastname: Halonen
authors.forename: L M
authors.initials: LM
authors.lastname: Taussig
mesh_terms: D002452:Cell Count / Q000187:drug effects; D003208:Concanavalin A / Q000494:pharmacology; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016131:Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D008297:Male; D010835:Phytohemagglutinins; D011043:Pokeweed Mitogens
chemical_list: D010835:Phytohemagglutinins; D011043:Pokeweed Mitogens; D003208:Concanavalin A