How long do we need to store cryopreserved cells and tissues.

Cryopreservation of haematopoietic tissue used in autologous and allogeneic transplantation was introduced to clinical practice at the author`s workplace in the 80´s and 90´s of the last century. Later cryopreservation of veins and arteries used for allogeneic transplantation was established. The authors also elaborated methodology of assessment of optimal level of graft stock in the tissue bank. Current requirements on longterm storage of cells and tissues are demonstrated on the group of cryopreserved vascular grafts, on concentrates of haematopoietic cells preserved for autologous transplantation and on donor lymphocyte concentrates used for guided graft versus host reaction applied after allogeneic haematopoietic stem cell transplantation. In the group of cryopreserved vascular tissue grafts the standard shelf-life of 5 years is satisfactory. The requirements on storage time in case of cryopreservation of haematopoietic tissue are much higher as a part of cell collection is routinely stored after first transplantation for the management of a relapse that may occur in future. Similarly in treatment by donor lymphocyte infusion in increasing cell doses cryopreserved concentrates may be applied within months or years after transplantation. The experience of the authors showed that storage of cryopreserved cells and tissues for years or decades has become a standard part of modern medical care.