Active Immunity
When B cells and T cells are activated by a pathogen, memory B-cells and T- cells develop. Throughout the lifetime of an animal these memory cells will “remember” each specific pathogen encountered, and are able to mount a strong response if the pathogen is detected again. This type of immunity is both active and adaptive because the body's immune system prepares itself for future challenges. Active immunity often involves both the cell-mediated and humoral aspects of immunity as well as input from the innate immune system. The innate system is present from birth and protects an individual from pathogens regardless of experiences, whereas adaptive immunity arises only after an infection or immunization and hence is "acquired" during life.
Read more about this topic: Immunity (medical)
Famous quotes containing the words active and/or immunity:
“I am grown old and my memory is not as active as it used to be. When I was younger I could remember anything, whether it had happened or not; but my faculties are decaying now, and soon I shall be so I cannot remember any but the things that never happened. It is sad to go to pieces like this, but we all have to do it.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“There is immunity in reading, immunity in formal society, in office routine, in the company of old friends and in the giving of officious help to strangers, but there is no sanctuary in one bed from the memory of another. The past with its anguish will break through every defence-line of custom and habit; we must sleep and therefore we must dream.”
—Cyril Connolly (1903–1974)