Helper T Cells Type 1, also known as Th1 cells, are a subtype of T helper cells that play a crucial role in the immune response. They are primarily involved in defending the body against intracellular pathogens, such as viruses and certain bacteria. Th1 cells produce specific signaling molecules called cytokines, particularly interferon-gamma, which activate other immune cells, including macrophages and cytotoxic T cells. These cells are essential for promoting cell-mediated immunity, which helps the body eliminate infected cells. A balanced Th1 response is vital for effective immune function, while an imbalance can lead to autoimmune diseases or chronic infections. Understanding Th1 cells is important for developing vaccines and therapies for various diseases.