Lactoferrin at basal side of mouse mammary epithelium derives in part from stroma cells.
Lactoferrin is synthesized by glandular epithelial cells and neutrophils and is also present on both sides of the mammary epithelium. We have studied the origin of lactoferrin detected in the various compartments of mouse mammary tissue. As revealed by immunogold electron microscopy, lactoferrin is present in mammary epithelial cells and in the basal region of the epithelium, associated with connective tissue and stroma cells at all physiological stages studied. A perturbation of protein synthesis or transport after in vitro treatment with cycloheximide or brefeldin A does not abrogate lactoferrin labelling in the basal region of the epithelium. The expression of lactoferrin has also been observed in the fat pads of mammary glands from mice surgically depleted of epithelial cells. The sealing of one teat for 24 h is accompanied by an increase in both the number of stroma cells and the labelling of myoepithelial cells. Thus, the lactoferrin present in the interstitial space of the mouse mammary epithelium originates in part from stroma cells. Possible roles of lactoferrin at the basal side of the mammary epithelium are discussed.
Pecorini
Chiara
C
Department of Veterinary Sciences and Technology for Food Safety, Veterinary Medicine Faculty, Università degli Studi di Milano, Via Celoria 10, 20133, Milan, Italy.
Delpal
Serge
S
Truchet
Sandrine
S
Le Provost
Fabienne
F
Baldi
Antonella
A
Ollivier-Bousquet
Michèle
M
D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D020126:Brefeldin A / Q000494:pharmacology; D002450:Cell Communication; D016764:Cell Polarity; D049109:Cell Proliferation; D003238:Connective Tissue / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D005260:Female; D007774:Lactation; D007781:Lactoferrin / Q000378:metabolism*; D008321:Mammary Glands, Animal / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D011247:Pregnancy; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D021381:Protein Transport; D017154:Stromal Cells / Q000378:metabolism*
D011500:Protein Synthesis Inhibitors; D020126:Brefeldin A; D003513:Cycloheximide; D007781:Lactoferrin