An Old Story Back: Human Milk Antibodies' Protective Roles Against Allergy Development

Human milk is a rich source of immunomodulatory factors that influence the development of the infant immune system, including susceptibility to allergic diseases. Among these components, milk antibodies have been extensively studied for their role in protecting against infections; however, their potential contribution to allergy prevention may be equally important. The mechanisms of protection include allergen exclusion, enhanced and targeted antigen presentation, immune modulation via shaping of the infant gut microbiome, and direct regulation of gut immune responses. This review summarizes current evidence on the secretion of human milk antibodies, highlights what is known and what remains unclear about their role in allergy prevention and outlines the need for further research to develop antibody-based strategies for early allergy prevention.