title: High Levels of Chemokine C-C Motif Ligand 20 in Human Milk and Its Production by Oral Keratinocytes.
abstract: Chemokine C-C motif ligand 20 (CCL20) is implicated in the formation and function of mucosal lymphoid tissues. Although CCL20 is secreted by many normal human tissues, no studies have evaluated the presence of CCL20 in human milk or its production by oral keratinocytes stimulated by human milk.
  
  
  
  To evaluate the presence of CCL20 in breast milk and verify CCL20 secretion in vitro by oral keratinocytes stimulated with human and bovine milk, as well as its possible association with breast milk lactoferrin levels.
  
  
  
  The levels of CCL20 and lactoferrin were measured by enzyme-linked immunosorbent assay in human milk at three different stages of maturation from 74 healthy breastfeeding mothers. In vitro, oral keratinocytes were stimulated with human and bovine milk, and CCL20 was measured in their supernatant.
  
  
  
  High concentrations of CCL20 were detected in the human breast milk samples obtained during the first week (1,777.07 pg/mL) and second week postpartum (1,523.44 pg/mL), with a significantly low concentration in samples at 3-6 weeks postpartum (238.42 pg/mL; p < 0.0001). Human breast milk at different weeks postpartum stimulated higher CCL20 secretion by oral keratinocytes compared with bovine milk (p < 0.05). Such stimulation had no association with breast milk lactoferrin concentration.
  
  
  
  CCl20 is present at high levels in human milk, predominantly in the first and second week postpartum, but at significantly lower levels at 3-6 weeks postpartum. Human milk is capable of stimulating CCL20 secretion by oral keratinocytes, and this induction had no association with breast milk lactoferrin concentration.
authors.affiliation: 1 Department of Pediatrics, Ribeirão Preto School of Medicine, University of São Paulo , São Paulo, Brazil .
authors.forename: Alan G
authors.initials: AG
authors.lastname: Lourenço
authors.affiliation: 2 Department of Morphology, Physiology and Basic Pathology, Ribeirão Preto School of Dentistry, University of São Paulo , São Paulo, Brazil .
authors.forename: Marilena C
authors.initials: MC
authors.lastname: Komesu
authors.affiliation: 3 Department of Gynecology and Obstetrics, Ribeirão Preto School of Medicine, University of São Paulo , São Paulo, Brazil .
authors.forename: Geraldo
authors.initials: G
authors.lastname: Duarte
authors.affiliation: 1 Department of Pediatrics, Ribeirão Preto School of Medicine, University of São Paulo , São Paulo, Brazil .
authors.forename: Luiz A
authors.initials: LA
authors.lastname: Del Ciampo
authors.affiliation: 1 Department of Pediatrics, Ribeirão Preto School of Medicine, University of São Paulo , São Paulo, Brazil .
authors.forename: Marisa M
authors.initials: MM
authors.lastname: Mussi-Pinhata
authors.affiliation: 1 Department of Pediatrics, Ribeirão Preto School of Medicine, University of São Paulo , São Paulo, Brazil .
authors.forename: Aparecida Y
authors.initials: AY
authors.lastname: Yamamoto
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001942:Breast Feeding; D002417:Cattle; D054418:Chemokine CCL20 / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015603:Keratinocytes / Q000378:metabolism*; D007781:Lactoferrin / Q000378:metabolism*; D008024:Ligands; D008892:Milk / Q000737:chemistry*; D008895:Milk, Human / Q000737:chemistry*; D049590:Postpartum Period / Q000502:physiology*; D055815:Young Adult
chemical_list: C108355:CCL20 protein, human; D054418:Chemokine CCL20; D008024:Ligands; D007781:Lactoferrin
keywords: CCL20; human milk composition; lactoferrin; oral keratinocytes