A leukophil is a type of white blood cell that is involved in the immune response. Specifically, leukophils, or leukocytes, help defend the body against infections and foreign substances. They play a crucial role in identifying and eliminating pathogens, such as bacteria and viruses, thereby contributing to the body's overall defense mechanism. There are several types of leukocytes, including neutrophils, lymphocytes, and monocytes, each with distinct functions in the immune system.