title: Ontogeny of CD4+ T Lymphocytes With Phenotypic Susceptibility to HIV-1 During Exclusive and Nonexclusive Breastfeeding in HIV-1-Exposed Ugandan Infants.
abstract: Among infants exposed to human immunodeficiency virus (HIV) type 1, mixed breastfeeding is associated with higher postnatal HIV-1 transmission than exclusive breastfeeding, but the mechanisms of this differential risk are uncertain.
  
  
  
  HIV-1-exposed Ugandan infants were prospectively assessed during the first year of life for feeding practices and T-cell maturation, intestinal homing (β7hi), activation, and HIV-1 coreceptor (CCR5) expression in peripheral blood. Infants receiving only breast milk and those with introduction of other foods before 6 months were categorized as exclusive and nonexclusive, respectively.
  
  
  
  Among CD4+ and CD8+ T cells, the expression of memory, activation, and CCR5 markers increased rapidly from birth to week 2, peaking at week 6, whereas cells expressing the intestinal homing marker increased steadily in the central memory (CM) and effector memory T cells over 48 weeks. At 24 weeks, when feeding practices had diverged, nonexclusively breastfed infants showed increased frequencies and absolute counts of β7hi CM CD4+ and CD8+ T cells, including the HIV-1-targeted cells with CD4+β7hi/CCR5+ coexpression, as well as increased activation.
  
  
  
  The T-cell phenotype associated with susceptibility to HIV-1 infection (CCR5+, gut-homing, CM CD4+ T cells) was preferentially expressed in nonexclusively breastfed infants, a group of infants at increased risk for HIV-1 acquisition.
authors.affiliation: Departments of 1 Pediatrics and.|Mucosal and Vaccine Research Program Colorado, Infectious Diseases. University of Colorado-Anschutz Medical Campus, Aurora, and.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: McFarland
authors.affiliation: Departments of 1Pediatrics and.
authors.forename: Tina M
authors.initials: TM
authors.lastname: Powell
authors.affiliation: Makerere University-Johns Hopkins University Research Collaboration, and.
authors.forename: Carolyne
authors.initials: C
authors.lastname: Onyango-Makumbi
authors.affiliation: Department of Biostatistics and Informatics, Colorado School of Public Health, and.
authors.forename: Weiming
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Medicine.
authors.forename: Kelsey
authors.initials: K
authors.lastname: Melander
authors.affiliation: Makerere University Walter Reed Project, Kampala, Uganda.
authors.forename: Prossy
authors.initials: P
authors.lastname: Naluyima
authors.affiliation: Makerere University Walter Reed Project, Kampala, Uganda.
authors.forename: Samuel
authors.initials: S
authors.lastname: Okurut
authors.affiliation: US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Springs.|Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, and.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Eller
authors.affiliation: Johns Hopkins University School of Medicine, Baltimore, Maryland.|Makerere University-Johns Hopkins University Research Collaboration, and.
authors.forename: Mary Glenn
authors.initials: MG
authors.lastname: Fowler
authors.affiliation: Medicine.|Mucosal and Vaccine Research Program Colorado, Infectious Diseases. University of Colorado-Anschutz Medical Campus, Aurora, and.|Denver Veterans Affairs Medical Center, Colorado.
authors.forename: Edward N
authors.initials: EN
authors.lastname: Janoff
mesh_terms: D000293:Adolescent; D000328:Adult; D001942:Breast Feeding / Q000009:adverse effects*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000821:virology*; D002465:Cell Movement; D004198:Disease Susceptibility; D005260:Female; D015658:HIV Infections / Q000276:immunology* / Q000635:transmission; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D007156:Immunologic Memory; D007223:Infant; D007231:Infant, Newborn; D007422:Intestines / Q000276:immunology; D008213:Lymphocyte Activation; D038041:Lymphopoiesis; D009035:Mothers; D010641:Phenotype; D011446:Prospective Studies; D019713:Receptors, CCR5 / Q000096:biosynthesis; D014454:Uganda; D055815:Young Adult
chemical_list: D019713:Receptors, CCR5
keywords: CCR5; CD4+ T lymphocytes; HIV-1; T cell homing; breastfeeding; lymphocyte activation; postnatal transmission; α4β7.