Perspectives on immunoglobulins in colostrum and milk

Abstract: Immunoglobulins are an important component of the immune activity found in milk and colostrum. They are central to the immune connection that occurs when the mother transmits passive immunity to her offspring. The mechanism of transmission varies between mammalian species. Cattle provide readily available rich colostrum and milk in large quantities, making these secretions important potential sources of immune products that can be beneficial to humans. Immune milk is the term used to describe a range of bovine mammary gland products that have been tested for a number of diseases in humans. The use of colostrum or milk as a source of immunoglobulins, whether for the neonate of a secretion-producing species or for another species, can be considered in the context of the types of immunoglobulins in secretion, the mechanisms by which immunoglobulins are secreted, and the mechanisms by which the neonate or adult consuming the milk obtains immunological benefits.

An intriguing application of our knowledge of bovine colostrum and milk immunoglobulins lies in the potential to provide passive immunity to disease in other species, particularly humans. The ability to direct the cow's immune system to produce antigen-specific antibodies that are secreted into colostrum and milk and can be used to provide protection against a specific disease is still of interest. For example, the widespread consumption of immune milk from cows vaccinated against diseases such as avian influenza, SARS and other human respiratory diseases has been suggested as a potential way to slow disease outbreaks before they reach epidemic levels .A number of reviews have summarised and evaluated early attempts to develop and test the use of immune dairy products to provide passive immune protection. Several immune dairy products are commercially available.

Colostrum and milk are rich sources of immunoglobulins. These secretions have evolved through evolution to ensure the homologous transfer of passive immunity from mother to offspring. Immunoglobulins passed from a mother to her offspring, whether through transfer across the placenta or through the consumption of colostrum and milk, may provide an important link between the mother's immune experience and the infant's immune capacity. This immunological link also includes many immunological factors that may be present in mammary secretions other than immunoglobulins. Immunoglobulins in colostrum and milk also provide the potential for their immune function to benefit other animals, including humans. Studies have shown that bovine colostrum and milk, whether from cows immunized against specific pathogens or not, provide a medium for heterologous transfer of passive immunity and can offer protection against disease in many species. New technologies that enhance vaccination efficacy, increase the stability and extend the shelf life of the immunoglobulin preparation while minimising the impact of processing and prolonging the effectiveness of the immunoglobulin in the gut may increase the future use of colostrum and milk based on their potent immunological activity. Although the mechanisms by which immunoglobulins are transferred from mother to neonate and their role in the newborn have been well documented.

Hurley W.L., Theil P.K..
Nutrients. 3(4): 442-474.
2011