T helper cells are important to a person’s immune system response. These cells play a critical role in identifying infection agents in the body and then signaling other cells to go to the body’s defense. Since T helper cells are typically the first to recognize a virus or bacterium, they are often referred to as first responders. They do not, however, destroy bacteria or viruses themselves. Interestingly, some infection agents, such as human immunodeficiency virus (HIV), attach to these cells and interfere with their abilities to send other cells to work.
One type of cell that is critical in immune system response is the T helper cell. This type of cell moves through a person’s body in an effort to locate viruses, bacteria, or other antigens, which are substances that provoke a person's immune system to respond and defend the body. T helper cells do this by interacting with the substances that are invading and posing a threat to the body.
When a T helper cell comes into contact with an antigen, it responds in two different ways. Upon contact with an antigen, it begins a process called cell division. The cell division creates more T cells, which results in additional first responders to inform other immune response cells of the problem in the body. T helper cells also release substances called lymphokines and chemokines. Both substances are used to notify other immune response cells of the presence of a bacterium, virus, or other infection agent.
Unfortunately, there are some antigens that interfere with the work of the T helper cells. One example of this is HIV. When a person has HIV, the virus actually attaches to T helper cells and destroys them. As a result, the person’s T helper cells are unable to signal other cells to fight the virus, and the affected person’s immune system is crippled.
A T helper cell is not capable of destroying infection agents on its own, but its work is very important to other T cells and macrophages, which are a type of white blood cell that consumes foreign invaders. A T helper cell stimulates these cells to go into action to destroy the infection agents. These cells also work to get B cells started on creating antibodies against the infection. Antibodies are special types of proteins that attach to parts of an antigen. Once they do, they are able to block the effects of the antigen.