The main role of the immune response in the body is to protect against infections and disease. The immune system consists of various cells, tissues, and organs that work together to identify and eliminate pathogens, such as bacteria, viruses, and parasites. It recognizes foreign substances through specific receptors and initiates a defensive response, which may include the production of antibodies by B cells and the activation of T cells to destroy infected cells. Additionally, the immune system has a memory component, allowing for quicker and more efficient responses to previously encountered pathogens, thus providing long-term protection.