title: Trans-epithelial immune cell transfer during suckling modulates delayed-type hypersensitivity in recipients as a function of gender.
abstract: BACKGROUND
  Breast feeding has long term effects on the developing immune system which outlive passive immunization of the neonate. We have investigated the transfer of milk immune cells and examined the result of transfer once the recipients were adult.
  
  
  METHODS
  Non-transgenic mouse pups were foster-nursed by green fluorescent protein (GFP) transgenic dams for 3 weeks and the fate of GFP+ cells was followed by FACS analysis, immunohistochemistry and RT-PCR for GFP and appropriate immune cell markers. Pups suckled by non-transgenic dams served as controls.
  
  
  RESULTS
  Despite a preponderance of B cells and macrophages in the stomach contents of the pups, most cells undergoing trans-epithelial migration derived from the 3-4% of milk cells positive for T lymphocyte markers. These cells homed to the spleen and thymus, with maximal accumulation at 3-4 weeks. By sensitizing dams with an antigen which elicits a T cell-mediated delayed-type-hypersensitivity (DTH) response, we determined that nursing by a sensitized dam (compared to a non-sensitized dam) amplified a subsequent DTH response in females and yet suppressed one in males.
  
  
  CONCLUSIONS
  These results suggest that clinical evaluation weighing the pros and cons of nursing male versus female children by mothers with genetically-linked hypersensitivity diseases, such as celiac disease and eczema, or those in regions of the world with endemic DTH-eliciting diseases, such as tuberculosis, may be warranted.
authors.affiliation: Division of Biomedical Sciences, University of California Riverside, Riverside, California, USA.
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Ma
authors.forename: Barbara
authors.initials: B
authors.lastname: Walter
authors.forename: Ariel
authors.initials: A
authors.lastname: Deguzman
authors.forename: H Konrad
authors.initials: HK
authors.lastname: Muller
authors.forename: Ameae M
authors.initials: AM
authors.lastname: Walker
mesh_terms: D019264:Adoptive Transfer / Q000662:veterinary; D000818:Animals; D000831:Animals, Newborn; D000833:Animals, Suckling; D002465:Cell Movement / Q000276:immunology / Q000502:physiology; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006968:Hypersensitivity, Delayed / Q000276:immunology*; D007112:Immunity, Maternally-Acquired / Q000502:physiology; D007413:Intestinal Mucosa / Q000276:immunology* / Q000378:metabolism / Q000502:physiology; D007774:Lactation / Q000276:immunology*; D008297:Male; D008321:Mammary Glands, Animal / Q000276:immunology* / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D012727:Sex Characteristics; D013270:Stomach / Q000166:cytology
chemical_list: D049452:Green Fluorescent Proteins