The immune system is made up of a network of cells, tissues, and organs that work together to protect the body against infectious organisms and other invaders. The immune system is the body’s natural defense mechanism. The function of this system is to prevent or reduce the occurrence of infection. This is accomplished through the coordinated function of the body’s immune cells. The immune system is divided into two systems:
- The innate response in a non-specific immune response that serves as the first line of defense against numerous germs and parasitic pathogens. Physical deterrents such as skin, chemical deterrents such as enzymes found in perspiration and saliva, and inflammatory reactions stimulated by immune cells encompass the innate immune system. The innate immune response is not specific to any pathogen. White blood cells involved in the innate immune response include macrophages, dendritic cells, and granulocytes (neutrophils, eosinophils, and basophils). These cells respond immediately to threats and are also involved in the activation of adaptive immune cells.
- The adaptive response provides a specific defense mechanism in which immune cells respond to specific pathogens and provide protective immunity. Like innate immunity, adaptive immunity includes two components: