The present invention is directed to methods of inducing a phenotypic change in a population of monocytes and/or macrophages. The method includes administering to the population of monocytes and/or macrophages, a macrophage stimulating agent coupled to a carrier molecule, wherein the carrier molecule facilitates macropinocytic uptake of the agent by monocytes and macrophages in the population and is defective in neonatal Fc receptor binding, wherein the administering induces a phenotypic change in the monocytes and macrophages in the population.