title: Effects of human immunodeficiency virus type 1 infection on CCR5 and CXCR4 coreceptor expression on CD4 T lymphocyte subsets in infants and adolescents.
abstract: HIV-1 infection alters expression of CCR5 and CXCR4 on CD4 T cells in adults, although an effect by virus on expression of coreceptor genes in pediatric subjects is unknown. We designed an exploratory study to evaluate surface expression of CXCR4 and CCR5 on CD45RA and CD45RO subsets of CD4 T lymphocytes from 17 HIV-1-infected infants and adolescents and 16 healthy age-matched individuals. While age in the absence of HIV-1 infection was unrelated to coreceptor expression, infection affected coreceptor expression differentially in infants and adolescents. Among infected adolescents, CCR5 and CXCR4 expression was significantly increased on CD4 CD45RO T cells, while CXCR4 was diminished in the CD4 CD45RA subset. Although HIV-1 infection in infants was also associated with increased CXCR4 expression on the CD4 CD45RO subset, in contrast to adolescents, infection in infants had no impact on coreceptor expression within the CD45RA CD4 subset. The proportion of CD4 T cells coexpressing CD45RA and CD45RO was increased by infection in both infants and adolescents. The CD45RA CD45RO subset in culture expressed high levels of CD4, CXCR4, and CD69, an early activation marker, and was highly susceptible to HIV-1 infection and replication. Infection of transitional CD4 T cells coexpressing CD45RA and CD45RO could contribute in part to provirus in either CD45RA or CD45RO subsets. Deleterious effects by HIV-1 infection on CD4 T cell homeostasis were greater in infants then adolescents, indicating that adolescence may be an optimal age group for assessing vaccines to prevent or treat HIV-1 infection.
authors.affiliation: Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, Florida 32610, USA.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Tuttle
authors.forename: Carter R
authors.initials: CR
authors.lastname: Coberley
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Xie
authors.forename: Zhong C
authors.initials: ZC
authors.lastname: Kou
authors.forename: John W
authors.initials: JW
authors.lastname: Sleasman
authors.forename: Maureen M
authors.initials: MM
authors.lastname: Goodenow
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism / Q000821:virology*; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D005260:Female; D015658:HIV Infections / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000378:metabolism / Q000472:pathogenicity*; D006801:Humans; D007223:Infant; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008297:Male; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D019713:Receptors, CCR5 / Q000378:metabolism*; D019718:Receptors, CXCR4 / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000378:metabolism*
chemical_list: D019713:Receptors, CCR5; D019718:Receptors, CXCR4; D017493:Leukocyte Common Antigens; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1