Rating Newest Oldest. Best Answer: Helper T Cells are a type of white blood cell that play an important role in establishing and maximizing the capabilities of the immune system. The difference between Helper T cells and Cytotoxic cells is that the Helper T Cells have no cytotoxic or phagocytic activity. In other words, they cannot kill infected host cells (also known as somatic cells) or pathogens, and without other immune cells they would usually be considered useless against an infection.