There are two types of T cells: helper cells and what other type?

The other type of T cell, in addition to helper cells, is often referred to as cytotoxic T cells, which are commonly known as "killer" cells. These cytotoxic T cells play a crucial role in the immune response by identifying and destroying infected or abnormal cells, such as cancer cells.

Helper T cells are primarily responsible for aiding other immune cells in their response to pathogens, including enhancing the function of B cells and cytotoxic T cells. The collaboration between helper T cells and killer T cells is essential for a robust adaptive immune response.

While other types of T cells, such as regulatory and memory T cells, serve important functions in maintaining immune balance and long-term immunity, they are not the primary counterpart to helper T cells in the context of attacking and eliminating infected cells. Hence, referring to killer cells clearly distinguishes the direct, effector function of those T cells involved in the cytotoxic response.