White blood cells are important for the immune response in humans. These cells come in many forms, and each type has a particular function in the overall process of immunity. This lesson addresses one of those cell types: the helper T cell.
Helper T Cells Defined
Immunity is defined in physiology as the body’s ability to resist infection and abnormal changes due to outside factors. This includes the body’s ability to protect against microbial organisms, damage within the body, and cancer development. Immunity requires the performance of several key cellular features of the body, including multiple types of leukocytes (white blood cells).
One of these leukocyte types is known as the helper T cell, which plays a vital role in the process of fighting infection.
T cells, which comprise a class of white blood cells in the body, are produced in the bone marrow during a process known as hemopoiesis. During this process, immature T cells are sent to the thymus gland in order to mature. Upon maturation, these cells are known as naïve, meaning they have not been exposed to any antigens (foreign substances) within the body.Helper T cells work in conjunction with all other white blood cells to support their functions in immunity. Certain macrophages (cells that ‘eat’ foreign materials) will digest bacteria and viruses that enter the body.
Afterward, these cells will present pieces of these foreign invaders on the cell surface for recognition. Helper T cells, then, recognize these pieces as being foreign, and this stimulates a double-pathway of cell response.Recognition is completed in the first step, as the helper T cell comes in contact with the macrophage and its displayed particles. The second step is verification, where the T cell determines if the particles being presented are, indeed, foreign. If both of these steps are completed, helper T cells will begin to function.
Function of Helper T Cells
After the helper T cells become functional, they will begin to proliferate (divide). These cells will develop into three different types of helper T cells:
- Effector helper T cells, which produce chemical signals to activate other white blood cells
- Memory helper T cells, which are sensitive to the foreign agent and are prepared in the event of a second exposure or infection
- Regulatory helper T cells, which reduces the immune response to ensure the body does not overreact to the antigen
In a sense, helper T cells are the ‘corporate managers’ of the immune response. They determine whether or not there is a viable threat in the body, they coordinate the activities of other white blood cells to fight the infection, and they help to monitor the work of the immune system to ensure a proper response. Without their functions, the body’s immune response would be seriously diminished, and we would be susceptible to many infectious diseases.
Helper T cells are important for the body’s immune response. They coordinate the activities of the other white blood cells in order to protect the body from infection. Helper T cells are required for the proper activation and monitoring of the immune cells in order to ensure that the immune response that develops is appropriate and effective.