Comprehensive immune support formula, promoting healthy natural killer cells, macrophage, T-cells, and cell division Transfer Factor Multi-Immune is a daily use immune support product. For healthy people it promotes healthy NK cell levels, keeping bugs at bay. For immune compromised individuals, it assists the body in bringing NK cell levels to where they need to be for optimal health. Transfer Factor works on the cellular (TH1) immunity level (as opposed to humoral (TH2) immunity), and they are often used to promote a balanced immune system (Th1/Th2).