TB Is a Contact Hypersensitivity Test?

Innate lymphocytes are in the same family as B and T cells. They respond rapidly to infection by secreting Perforin or Grandzyme, but they also secrete a lot of cytokines like interferon gamma which can recruit other cells for killing. So it's not that crazy that innate cells might have this type of memory because when you look at some of our earliest vertebrates,. jawless fish, jawless fish may have had similar memories.