Assessing the immunomodulatory role of heteroglycan in a tumor spheroid and macrophage co-culture model system.

•A tumor spheroid and macrophage co-culture system was developed.•Immune stimulating functions of heteroglycan was tested in such co-culture models.•Macrophage mediated tumor cytotoxicity was observed after heteroglycan treatment.•Heteroglycan exposure oriented the macrophages into tumor-inhibiting type.