Single domain antibodies (sdAbs) are antibody fragments produced by the immune cells of certain animal species. They are significantly smaller than conventional antibodies and can bind antigens, but do not signal and activate host immune cells. sdAbs can be developed against essential components of pathogens, resulting in neutralization of function and elimination or reduction of pathogenicity.
Due to their small size and relatively simple structure, sdAbs can be faithfully and economically produced in clinically relevant quantities, for example, by using probiotic microorganisms. sdAbs have significant cost and production advantages over conventional antibodies, and hold great potential in addressing pressing health issues in food animal production.