title: Detection of β-lactoglobulin in human breast-milk 7 days after cow milk ingestion.
abstract: BACKGROUND
  β-lactoglobulin (BLG), a major allergen in cow milk (CM) can be detected in human breast-milk (BM) and is associated with exacerbation of symptoms in breastfed infants with cow milk protein allergy (CMPA). Currently, it is not known how long lactating mothers who consume dairy products need to withhold breastfeeding.
  
  
  OBJECTIVE
  To elucidate the kinetics of BLG in BM after maternal ingestion of a single dose of CM.
  
  
  METHODS
  Nineteen lactating mothers, four of whom had infants with CMPA, were instructed to avoid CM for 7 days before ingesting a single dose of CM and to continue to withhold CM thereafter throughout the study period. BLG was measured by ELISA in BM from 15 mothers of healthy infants before and at 3, 6 and 24 h, and 3 and 7 days after CM ingestion. Four pairs of mothers and CMPA infants were enrolled for BM challenge after the mothers had ingested CM.
  
  
  RESULTS
  After CM ingestion, the level of BLG in BM increased significantly from 0.58 ng/ml (0.58 g/L) (IQR 0.38-0.88) to a peak level of 1.23 ng/ml (IQR 1.03-2.29), p < 0.001. The BLG level on day 3 (1.15 ng/ml, IQR 0.89-1.45) and day 7 (1.08 ng/ml (IQR 0.86-1.25) after CM ingestion was significantly higher than baseline (p = 0.01 and p = 0.001, respectively). BLG was detected in all BM samples from the four mothers of CMPA infants after CM ingestion, and the level was not different from that in the mothers of the 15 healthy infants. Three of the four CMPA infants developed symptoms such as maculopapular rash and hypersecretion in the airways after BM challenge.
  
  
  CONCLUSIONS
  BLG can be detected in BM up to 7 days after CM ingestion. Lactating mothers should suspend breastfeeding to CMPA infants more than 7 days after CM ingestion.
authors.affiliation: a Department of Microbiology, Faculty of Science , Mahidol University , Bangkok , Thailand.|b Systems of Biology of Diseases Research Unit, Faculty of Science , Mahidol University , Bangkok , Thailand.
authors.forename: Ponpan
authors.initials: P
authors.lastname: Matangkasombut
authors.affiliation: c Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital , Mahidol University , Bangkok , Thailand.
authors.forename: Savitree
authors.initials: S
authors.lastname: Padungpak
authors.affiliation: a Department of Microbiology, Faculty of Science , Mahidol University , Bangkok , Thailand.
authors.forename: Sasikanya
authors.initials: S
authors.lastname: Thaloengsok
authors.affiliation: c Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital , Mahidol University , Bangkok , Thailand.
authors.forename: Wasu
authors.initials: W
authors.lastname: Kamchaisatian
authors.affiliation: c Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital , Mahidol University , Bangkok , Thailand.
authors.forename: Cherapat
authors.initials: C
authors.lastname: Sasisakulporn
authors.affiliation: c Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital , Mahidol University , Bangkok , Thailand.
authors.forename: Wanlapa
authors.initials: W
authors.lastname: Jotikasthira
authors.affiliation: c Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital , Mahidol University , Bangkok , Thailand.
authors.forename: Suwat
authors.initials: S
authors.lastname: Benjaponpitak
authors.affiliation: c Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital , Mahidol University , Bangkok , Thailand.
authors.forename: Wiparat
authors.initials: W
authors.lastname: Manuyakorn
mesh_terms: D000485:Allergens / Q000032:analysis* / Q000493:pharmacokinetics*; D000818:Animals; D002417:Cattle; D004032:Diet; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007782:Lactoglobulins / Q000032:analysis* / Q000493:pharmacokinetics*; D008297:Male; D008895:Milk, Human / Q000737:chemistry*; D009035:Mothers; D013997:Time Factors
chemical_list: D000485:Allergens; D007782:Lactoglobulins
keywords: Breast-milk; allergy; avoidance; cow milk; human; infant; lactation; β-lactoglobulin