Kaplan Nursing Entrance Practice Exam

What is the primary role of Helper T cells in the immune system?

1. To directly attack infected cells

2. To coordinate immune responses

3. To filter pathogens from the blood

4. To produce antibodies

The correct answer is: To coordinate immune responses

Helper T cells play a crucial role in the immune system primarily by coordinating immune responses. They are pivotal in the activation and regulation of immune cells, including B cells, cytotoxic T cells, and other components of the immune system. When activated by recognizing antigens presented by antigen-presenting cells, Helper T cells release cytokines, which are signaling molecules that promote the differentiation and proliferation of other immune cells, enhancing the overall immune response. For example, by aiding B cells in their maturation, Helper T cells stimulate them to produce antibodies that target specific pathogens. They also assist cytotoxic T cells to recognize and kill infected cells. This coordination ensures a robust and effective immune response, allowing the body to respond appropriately to various infections. The other options describe functions of different cells or components of the immune system. Directly attacking infected cells is primarily the role of cytotoxic T cells. Filtering pathogens from the blood mainly occurs in organs such as the spleen and lymph nodes rather than a specific cell type. Producing antibodies is the main function of B cells, not Helper T cells. Thus, the key function of Helper T cells lies in their role as coordinators within the immune system.