Abstract: One embodiment of the current disclosure relates to an immune-modulating composition comprising a hydrogel-forming polymer, an immune-modulating biomolecule operable to recruit or retain an immune cell, and an antigen-related biomolecule. Another embodiment of the current disclosure relates to a method of providing an antigen to an antigen presenting cell in an animal by administering to the animal at an administration site an immune-modulating composition as described above. Next, one forms a hydrogel in-situ from the hydrogel-forming polymer, then recruits at least one antigen presenting cell to the administration site using the immune-modulating biomolecule, and finally inducing phagocytosis of the at least one antigen-related biomolecule by the antigen presenting cell.