Evolutionary History of the Immune system
Abstract-As we know that there are two categories are Adaptive and Innate where the Adaptive Immune
System (AIS) in mammals, which is centered on lymphocyte bearing antigens receptors that are generated
by semantic re-combinations which arose around 500 million years ago in Jawed fish.
Recently, a non- RAG based AIS with similarities to the jaw vertebrate AIS. They include two lymphoid
cell lineages. The latest advantages in thus field and space on the selective pressures that led to the
maintenance of AIS.
The Innate category are the basic physiological reactions of all living organisms are
how the hosts responses against invading pathogens. As we saw that series of defense mechanisms have
evolved to secure cellular integrity, homeostasis and the survival of the hosts. In invertebrates, some of
them are in range of Protozoans to metazoans, which binds to foreign elements and differentiate self from
non-self. The cells which poses Macrophage like appearance and function and the repair and or fight
function associated with molecular patterns. Organisms which are all development stages, have in order to
survive, applied available genes and functions which may lost or changed their functions through evolution.
Keywords: evolution, immunity, innate immunity, adaptive immunity, invertebrates, vertebrates
Introduction-