Th cell, short for T helper cell, is a type of white blood cell that plays a vital role in the immune response of vertebrates, including humans. Th cells are a subgroup of T cells, and their primary function is to regulate and coordinate the immune system by directing other immune cells to respond to foreign substances, such as bacteria or viruses.
Th cells achieve this by recognizing, binding, and interacting with antigens, which are molecules or fragments from invading pathogens or abnormal cells. Upon antigen recognition, Th cells become activated and produce various cytokines, chemical messengers that help recruit and activate other immune cells to eliminate the threat. These cytokines determine the type of immune response that will be initiated, whether it is a cellular or humoral response.
In addition to providing assistance to other immune cells, Th cells can differentiate into distinct subtypes, including Th1, Th2, Th17, and T regulatory cells. Each subtype has a specific function and can influence the immune response in different ways. For example, Th1 cells are involved in fighting intracellular pathogens, while Th2 cells are essential for eliminating extracellular parasites.
Defects or imbalances in Th cell populations can lead to immune dysregulation and the development of various diseases, including autoimmune disorders, allergies, and immunodeficiencies. Therefore, understanding the functioning and regulation of Th cells is crucial for developing effective therapeutic strategies to modulate immune responses.
