Vectorial secretion of vascular endothelial growth factor by polarized human endometrial epithelial cells.
OBJECTIVE
To analyze directional vascular endothelial growth factor (VEGF) secretion in polarized human endometrial epithelial cell cultures. VEGF has distinct distribution patterns in human endometrium. Stromal cells are diffusely positive for VEGF messenger RNA and protein, whereas glandular epithelium shows focal VEGF immunostaining at the apical surface. The epithelial distribution suggests that VEGF is secreted into gland lumina, potentially influencing the nutrition and/or apposition of the developing blastocyst.


METHODS
Controlled in vitro study of protein secretion by polarized endometrial epithelial cells established on polyethylene filters.


METHODS
University hospital.


METHODS
Endometrial biopsies were obtained from healthy, ovulatory women undergoing elective surgery.


METHODS
Primary endometrial epithelial cells were cultured.


METHODS
VEGF mRNA and protein production were measured in polarized cells. The vectorial secretion of VEGF was determined.


RESULTS
VEGF production by endometrial epithelial cells was verified by Northern blotting and immunoassays of conditioned media. The mean (+/-SD) apical secretion of VEGF was 3.9 +/- 1.4 ng per 10(5) cells every 48 hours and the mean (+/-SD) basal secretion was 0.8 +/- 0.2 ng per 10(5) cells every 48 hours. In contrast, the apical and basal secretion of a soluble cellular isoform of fibronectin were 2.76 +/- 0.96 ng per 10(5) cells every 48 hours and 2.64 +/- 1.79 ng per 10(5) cells every 48 hours, respectively.


CONCLUSIONS
VEGF is secreted preferentially into the lumina of endometrial glands. Apical VEGF may be an endometrial signal for blastocyst development or implantation.
Hornung
D
D
Reproductive Endocrinology Center, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, USA.
Lebovic
D I
DI
Shifren
J L
JL
Vigne
J L
JL
Taylor
R N
RN
D000328:Adult; D016764:Cell Polarity; D002478:Cells, Cultured; D004717:Endometrium / Q000166:cytology / Q000378:metabolism*; D016228:Endothelial Growth Factors / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D008222:Lymphokines / Q000378:metabolism*; D020794:Receptor Protein-Tyrosine Kinases / Q000032:analysis; D017978:Receptors, Growth Factor / Q000032:analysis; D040262:Receptors, Vascular Endothelial Growth Factor; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D008222:Lymphokines; D017978:Receptors, Growth Factor; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D020794:Receptor Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor