Passive and active protection against disorders of the gut

Abstract The large surface area of mucosal surfaces, particularly of the gastrointestinal tract, is protected against microorganisms and environmental antigens by various innate factors (e.g., mucins, lactoferrin, and others) and specific antibodies which are of IgA, or in some species, IgG Isotypes. Passive protection provided by effective prenatal transplacental transport of maternal antibodies and/or post‐natal consumption of milk antibodies in breastfed newborns, is essential for the survival of neonates. Passive protection of mucosal surfaces by pre‐formed antibodies in non‐breast juveniles or adults is currently used only on an experimental basis: IgA‐enriched preparations of gamma‐globulin have been successfully given to children, and antibodies specific for several gastrointestinal pathogens have been isolated from immunized cows’ milk, hens’ eggs, or transgenic plants. Systemic administration of pre‐formed antibodies is effective for protection against intestinal pathogens in species (e.g., mice,...