Identification of the human beta-casein C-terminal fragments that specifically bind to purified antibodies to bovine beta-lactoglobulin

Detection of Bovine Alpha-S1-Casein in Term and Preterm Human Colostrum with Proteomic Techniques

Due to increased social awareness of allergens and population hyper-sensitization, the reported incidence of allergic reactions to food allergens has increased over the past two decades. Cow's milk proteins (CMPs) are among the most common food allergens. The aim of this study was to use proteomics techniques to investigate cow's milk allergens in both full-term human colostrum and in preterm newborns' mothers - where both groups showed no prior allergen detection – in order to understand whether cow's milk allergens could be a cause of sensitization established through lactation. The most relevant finding was the detection of the intact bovine alpha-S1-casein in both term and preterm colostrum. Using techniques detailed in this paper and which allowed for direct protein identification, β-lactoglobulin was not detected in any of the colostrum samples. According to our results, bovine alpha 1 casein is considered a major cow's milk allergen, is readily secreted in human milk, and so could be considered a possible cause of sensitization in exclusively breastfed infants.

Detection of cow's milk proteins and minor components in human milk using proteomics techniques

Cow's milk proteins (CMPs) are the best characterized food allergens. The aim of this study was to investigate cow's milk allergens in human colostrum of term and preterm newborns' mothers, and other minor protein components by proteomics techniques, more sensitive than other techniques used in the past. Sixty-two term and 11 preterm colostrum samples were collected, subjected to a treatment able to increase the concentration of the most diluted proteins and simultaneously to reduce the concentration of the proteins present at high concentration (Proteominer Treatment), and subsequently subjected to the steps of proteomic techniques. The most relevant finding in this study was the detection of the intact bovine alpha-S1-casein in human colostrum, then bovine alpha-1-casein could be considered the cow's milk allergen that is readily secreted in human milk and could be a cause of sensitization to cow's milk in exclusively breastfed predisposed infants. Another interesting result was the detection, at very low concentrations, of proteins previously not described in human milk (galectin-7, the different isoforms of the 14-3-3 protein and the serum amyloid P-component), probably involved in the regulation of the normal cell growth, in the pro-apoptotic function and in the regulation of tissue homeostasis. Further investigations are needed to understand if these families of proteins have specific biological activity in human milk.

Benefits and risks of breastfeeding

In the absence of significant, unpreventable risks, breastfeeding should be the norm for the nourishment of human infants and should, therefore, be encouraged for populations in all countries. Continued efforts of international and national agencies and healthcare professionals to aid and abet breastfeeding, reduce the risks that occur in some women during breastfeeding, provide the safest substitutes for human milk when that is necessary, and encourage further research into the posed questions should considerably improve the health of many children.