Vascular endothelial growth factor (VEGF) is present in human breast milk and its receptor is present on intestinal epithelial cells

VEGF (vascular endothelial growth factor) is a multifunctional cytokine act ive on blood vessel cells. The present study measured VEGF in the aqueous p hase of human milk and examined how the concentration varied with gestation al age and the duration of lactation after birth, We hypothesized that VEGF -specific receptors were present on the apical surface of intestinal epithe lial cells. The concentration of monomeric VEGF (containing 165 residues) m easured by ELISA in the breast milk was 2 orders of magnitude greater than that measured in the serum of normal adults. The VEGF165 concentration in t he first week of lactation was greater in the breast milk of mothers of ful l-term than in preterm babies (p < 0.05). The concentration in the breast m ilk of mothers of full-term infants decreased (p < 0.01) after the first we ek of lactation. Scatchard analysis of radioligand-receptor binding showed the presence of specific receptors for I-125-VEGF165 on the surface of Caco -2, an intestinal epithelial cell line, with a k(d) of 2.85 to 4 nM. Revers e transcriptase PCR of Caco-2 cell RNA showed mRNA for the VEGF receptor fl t-1. in conclusion, VEGF is present in high concentrations in breast milk a nd binds to specific receptors on cells derived from intestinal epithelium.