title: Intestinal fatty acid-binding protein: a possible marker for gut maturation.
abstract: BACKGROUND
  Gut immaturity is linked with postnatal intestinal disorders. However, biomarkers to assess the intestinal developmental stage around birth are lacking. The aim of this study was to gain more insight on intestinal fatty acid-binding protein (I-FABP) as an indicator of gut maturity.
  
  
  METHODS
  Antenatal I-FABP distribution and release was investigated in extremely premature, moderately premature, and term lambs, and these findings were verified in human urinary samples. Ileal I-FABP distribution was confirmed in autopsy material within 24 h postnatally.
  
  
  RESULTS
  Median (range) serum I-FABP levels were lower in extremely premature lambs compared with moderately premature lambs (156 (50.0-427) vs. 385 (100-1,387) pg/ml; P = 0.02). Contrarily, median early postnatal urine I-FABP levels in human infants were higher in extremely premature compared with moderately premature and term neonates (1,219 (203-15,044) vs. 256 (50-1,453) and 328 (96-1,749) pg/ml; P = 0.008 and P = 0.04, respectively). I-FABP expression was most prominent in nonvacuolated enterocytes and increased with rising gestational age (GA) in ovine and human tissue samples. The epithelial distribution pattern changed from a phenotype displaying I-FABP-positive enterocytes merely in the crypts early in gestation into a phenotype with I-FABP expressing cells exclusively present in the villus tips at term in ovine and human tissue.
  
  
  CONCLUSIONS
  In this ovine and human study, increasing GA is accompanied by an increase in I-FABP tissue content. Cord I-FABP levels correlate with gestation in ovine fetuses, identifying I-FABP as a marker for gut maturation. Raised postnatal urine I-FABP levels in preterm human infants may indicate intestinal injury and/or inflammation in utero.
authors: Department of Surgery, Maastricht University Medical Center and Nutrition and Toxicology Research Institute (NUTRIM), Maastricht, The Netherlands.
authors: Kostan W
authors: KW
authors: Reisinger
authors: Department of Pediatrics, Maastricht University Medical Center and School for Oncology and Developmental Biology (GROW), Maastricht, The Netherlands.
authors: Marieke
authors: M
authors: Elst
authors: Department of Surgery, Maastricht University Medical Center and Nutrition and Toxicology Research Institute (NUTRIM), Maastricht, The Netherlands.
authors: Joep P M
authors: JP
authors: Derikx
authors: Department of Pathology, University Medical Center, Utrecht, The Netherlands.
authors: Peter G J
authors: PG
authors: Nikkels
authors: Department of Pathology, Maastricht University Medical Center, Maastricht, The Netherlands.
authors: Bart
authors: B
authors: de Vries
authors: Department of Pediatrics & Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: Marlou P M
authors: MP
authors: Adriaanse
authors: 1] Department of Pediatrics, Maastricht University Medical Center and School for Oncology and Developmental Biology (GROW), Maastricht, The Netherlands [2] Department of Pediatrics & School for Mental Health and NeuroScience (MHeNS), Maastricht University, Maastricht, The Netherlands.
authors: Reint K
authors: RK
authors: Jellema
authors: 1] Department of Pediatrics, Maastricht University Medical Center and School for Oncology and Developmental Biology (GROW), Maastricht, The Netherlands [2] Department of Pediatrics & School for Mental Health and NeuroScience (MHeNS), Maastricht University, Maastricht, The Netherlands.
authors: Boris W W
authors: BW
authors: Kramer
authors: Department of Pediatrics, Maastricht University Medical Center and School for Oncology and Developmental Biology (GROW), Maastricht, The Netherlands.
authors: Tim G A M
authors: TG
authors: Wolfs
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001344:Autopsy; D015415:Biomarkers / Q000378:metabolism; D020895:Enterocytes / Q000378:metabolism; D050556:Fatty Acid-Binding Proteins / Q000097:blood / Q000378:metabolism* / Q000652:urine; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D005865:Gestational Age; D006801:Humans; D007082:Ileum / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D062071:Infant, Extremely Premature; D007413:Intestinal Mucosa / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D008297:Male; D009024:Morphogenesis; D010641:Phenotype; D047928:Premature Birth; D012756:Sheep
chemical_list: D015415:Biomarkers; C493404:FABP2 protein, human; D050556:Fatty Acid-Binding Proteins