A Th2 response, or T-helper 2 response, is a type of immune reaction primarily involved in combating parasitic infections and allergic responses. It is characterized by the activation of T-helper cells, which release specific cytokines that promote the production of IgE antibodies and stimulate B cells. This response helps the body fight off certain pathogens and plays a role in allergic reactions. In a Th2 response, the cytokines released include IL-4, IL-5, and IL-13. These molecules encourage the growth and activation of eosinophils and mast cells, which are crucial for defending against parasites. However, an overactive Th2 response can lead to conditions like asthma and allergies, highlighting the importance of balanced immune responses.