Cross-reactivity analysis of milk proteins from different goat breeds with cow?s milk allergens using a proteomic approach

Introduction: Goat's milk thought to be a good substitute for cow's milk protein allergic (CMPA) individuals. However, there is growing evidence that their proteins have cross-reactivities with cow's milk allergens. This study aimed to profile and compare milk proteins from different goat breeds that have cross-reactivity to cow's milk allergens.Methodology: Proteomics was used to compare protein extracts of skim milk from Saanen, Jamnapari, and Toggenburg. Cow's milk was used as a control. IgE-immunoblotting and mass spectrometry were used to compare and identify proteins that cross-reacted with serum IgE from CMPA patients (n = 10).Results: The analysis of IgE-reactive proteins revealed that the protein spots identified with high confidence were proteins homologous to common cow's milk allergens such as alpha-S1-casein (alpha S1-CN), beta-casein (beta-CN), x-casein (x-CN), and beta-lactoglobulin (beta-LG). Jamnapari's milk proteins were found to cross-react with four major milk allergens: alpha-S1-CN, beta-CN, x-CN, and beta-LG. Saanen goat's milk proteins, on the other hand, cross-reacted with two major milk allergens, alpha-S1-CN and beta-LG, whereas Toggenburg goat's milk proteins only react with one of the major milk allergens, x-CN. Conclusion: These findings may help in the development of hypoallergenic goat milk through cross-breeding strategies of goat breeds with lower allergenic milk protein contents.