Tissue Therapy, Historical

**Definition:** 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.

**Tree numbers:** - E02.095.682.884 - E02.190.701.884