Which cells are known for their role in destroying virus-infected cells and tumor cells in the innate immune response?

Natural killer cells are a crucial component of the innate immune response, primarily responsible for identifying and eliminating virus-infected cells and tumor cells. They function without prior sensitization to antigens, allowing for a rapid response to threats in the body.

Natural killer cells recognize stressed cells in the absence of antibodies and major histocompatibility complex (MHC) molecules, which is pivotal for their ability to act quickly. They release cytotoxic granules that lead to the apoptosis of infected or abnormal cells. This mechanism is essential for controlling viral infections and preventing cancer progression.

In contrast, the other cells mentioned have different roles in the immune system. B cells are part of the adaptive immune response and are primarily responsible for antibody production. Helper T cells assist in activating and directing both B cells and other T cells, while suppressor T cells help modulate and down-regulate the immune response to prevent overactivity. Therefore, the specific ability of natural killer cells to destroy virus-infected and tumor cells makes them the correct answer in this context.