title: Evolution of the urinary proteome during human renal development and maturation: variations with gestational and postnatal age.
abstract: BACKGROUND
  Low birth weight is associated with deficits in nephron number in the infant kidney and increased risk of adulthood hypertension and renal dysfunction. Urinary biomarkers may be potential indicators of renal reserve, but little is known about the influence of gestational and postnatal age on the expression of urinary proteins. The aims of this study were to determine the relationships between selected urinary proteins and renal maturation. We hypothesized that urinary protein patterns would change over time during late nephrogenesis and renal maturation.
  
  
  METHODS
  Urine samples were collected at birth and over 12 mo from preterm (33-35 wk) and term (38-40 wk) infants. Candidate urinary proteins were identified by antibody array and quantified with enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Preterm infants at birth were found to have relatively elevated levels of insulin-like growth factor binding protein-1, -2, and -6, monocyte chemotactic protein-1, CD14, and sialic acid-binding Ig-like lectin 5. These markers gradually decline to levels similar to those of full-term infants by 2-6 mo of life. In contrast, many urinary markers in healthy full-term infants remain stable over the first year of life.
  
  
  CONCLUSIONS
  Gestational and postnatal age must be considered when evaluating the utility of urinary biomarkers.
authors.affiliation: Department of Pediatrics, University of Virginia, Charlottesville, USA. jrc6n@virginia.edu
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Charlton
authors.forename: Victoria F
authors.initials: VF
authors.lastname: Norwood
authors.forename: Susan C
authors.initials: SC
authors.lastname: Kiley
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Gurka
authors.forename: Robert L
authors.initials: RL
authors.lastname: Chevalier
mesh_terms: D000367:Age Factors; D015703:Antigens, CD / Q000652:urine; D015214:Antigens, Differentiation, Myelomonocytic / Q000652:urine; D018932:Chemokine CCL2 / Q000652:urine; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000378:metabolism*; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000652:urine; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000652:urine; D018976:Insulin-Like Growth Factor Binding Protein 6 / Q000652:urine; D007668:Kidney / Q000254:growth & development* / Q000378:metabolism*; D037102:Lectins / Q000652:urine; D008297:Male; D011507:Proteinuria / Q000652:urine*; D020543:Proteome / Q000235:genetics*; D018709:Statistics, Nonparametric
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D018932:Chemokine CCL2; C032231:IGFBP1 protein, human; D018970:Insulin-Like Growth Factor Binding Protein 1; D018971:Insulin-Like Growth Factor Binding Protein 2; D018976:Insulin-Like Growth Factor Binding Protein 6; D037102:Lectins; D020543:Proteome; C114531:SIGLEC5 protein, human