Historically, tissue transplantation, especially of refrigerated tissue (after Filatov).
It was theorized that nonspecific substances, capable of initiating restorative processes,
formed in tissues when refrigerated. Cell therapy (after Niehans) refers to implantation
of tissue by injection. Originally this involved fresh cells but later frozen or lyophilized
cells
Note publique d''information :
Historically, substances that are produced in isolated animal and vegetable tissues
in the process of adapting to adverse conditions, that when injected into the body
stimulate and accelerate tissue regeneration