The Japanese word for Japan is æ¥æ¬, which is pronounced Nippon or Nihon and literally means the origin of the sun. The earliest record of the name Nihon appears in the Chinese historical records of the Tang dynasty, the Old Book of Tang.
Primary versus Secondary Immune Response The primary immune response occurs the first time that the immune system comes in contact with the antigen.
Type IV hypersensitivity. Type 4 hypersensitivity is often called delayed type hypersensitivity as the reaction takes several days to develop. Unlike the other types, it is not antibody-mediated but rather is a type of cell-mediated response. CD4+ T h 1 helper T cells recognize antigen in a complex with the MHC class II major histocompatibility complex on the surface of antigen-presenting cells.