The cells we are interested in and focus on are called glia cells, more precisely Müller glia. Müller glia are the predominant glia in the neural retina and named after Professor Heinrich Müller (described in 1851). Glia cells per se are known as the support cells in the central nervous system, have a variety of other functions including maintaining the homeostasis of the tissue, but also protection after injury or disease. Glia cells, as part of their protective function, undergo morphological changes to create a barrier and a non-permissive environment for regeneration. This glial response, called gliosis, is a very complex process and includes a variety of factors and mechanisms which are not fully understood.