HLF and neoplasm: Depending on the external stimulus (pathogens, allergen, tumor antigens, etc.)and host immune status, hLf can modulate IL-4, IL-2, IL-12, or IFN-γ levels, thus providing different outcomes: strong Th1 polarization (infections, tumor), reduction of excessive Th1 responses, and correction of Th1/Th2 balance (allergy, autoimmunity).