Epidermal growth factor in human and bovine milk

Area of Science:

• Biochemistry
• Analytical Chemistry
• Pediatrics

Background:

• Epidermal growth factor (EGF) is a vital polypeptide hormone.
• EGF plays a role in cell growth and development, present in milk.
• Accurate quantification of EGF in milk is crucial for nutritional and developmental studies.

Purpose of the Study:

• To compare the accuracy of different methods for measuring epidermal growth factor (EGF) concentration in human and bovine milk.
• To determine the precise levels of EGF in human milk, bovine milk, and infant formulas.
• To establish reliable protocols for analyzing trace growth factors in complex biological matrices.

Main Methods:

• Radioreceptor assay (RRA) was employed to quantify EGF.
• Two sources of EGF receptors were tested: human placental plasma membranes and intact A431 epidermoid carcinoma cells.
• EGF concentrations were measured in human milk, bovine milk, and cow's milk-based infant formulas.

Main Results:

• Human placental membranes yielded inaccurate EGF measurements, overestimating human milk levels and providing erroneous results for bovine milk.
• Intact A431 cells provided more reliable EGF quantification.
• Human milk contained significantly higher EGF concentrations (30-40 ng/ml) compared to bovine milk (<2 ng/ml).
• No detectable EGF activity was found in cow's milk-based infant formulas.

Conclusions:

• Intact cells are superior to placental membranes for accurate EGF measurement in milk via RRA.
• Human milk is a richer source of EGF than bovine milk.
• Current infant formulas derived from cow's milk lack measurable EGF, suggesting potential differences in nutritional value compared to human milk.