Refrigeration devices containing tissue shall be suitable for the use intended and procedures for monitoring such devices shall be validated so that tissues are maintained at the required storage temperature. Continuous monitoring and recording of temperature, together with suitable alarm systems, shall be employed on all storage refrigerators, freezers and liquid nitrogen tanks.
Every effort should be made to avoid cross-contamination of material stored in liquid nitrogen vessels. Material should be stored in the vapour phase of liquid nitrogen, not immersed in the liquid phase. Liquid nitrogen storage vessels should be designed to incorporate automatic filling systems to avoid transfer of filling hoses between vessels. Thermocouple temperature probes should be placed in storage vessels, with at least one probe located in the warmest position, as determined by temperature mapping.
Frozen and cryopreserved tissue should be double wrapped during storage. The seals and the material employed must be validated for their use at the designated storage temperature and the conditions of use, to demonstrate integrity of the packaging and labelling. This is crucially important for storage in liquid nitrogen vessels because of the high levels of accumulated microbial contaminants found within these vessels.
Quarantined and released tissue must be stored in physically segregated, clearly designated locations distinct from each other.
Prior to any tissue being cleared for issue, all relevant records including donor records, processing and storage records, and post-processing quality control test results must have been reviewed, approved and documented as acceptable by the individual(s) responsible according to the relevant local standard operating procedures. Responsibilities for setting policies for exceptional release of tissues reside with the authorised medical officer.
There must be a documented policy for the discard of tissue unsuitable for clinical use. Records should include details of date and method of discard and reason for discard. Tissues for discard should be appropriately handled and disposed of in a manner compliant with local control of infection guidelines. Traceability records must be retained in the same way as for tissue used in human application.
Packaging must ensure integrity and maintain sterility of the contents of the final container and must also comply with current legislation.
The container must be labelled with the graft-specific identification (tissue type, batch and shipment number if applicable), expiry date and supplying Tissue Establishment, storage instructions and barcoded product description and instruction to see pack insert, as a minimum. In addition, more detailed information should be provided either on the label or package insert or both as follows:
For transport, the primary container must be placed in a shipping container that must be labelled with at least the following information:
All reasonable efforts must be made to ensure that tissues are sent to qualified individuals/organisations who have accepted responsibility for their proper handling and use. A written agreement must be in place between the Tissue Establishment and the organisation ordering the tissue.
Where tissue is transported in a refrigerated or frozen condition, adequate safeguards should be taken to ensure that the tissue remains at the designated temperature. Monitoring of temperature should be undertaken wherever practicable but if not, the method should at least have been validated to show that appropriate temperatures are maintained. Consideration should be given to the potential for extremes of external temperature during transportation.
The Human Tissue Act defines ‘Relevant Material’ as: “material, other than gametes, which consists of or includes human cells.” Tissue Establishments must determine for each type of graft they prepare, and the processing applied, whether or not a graft type is classified as Relevant Material. If so, the Tissue Establishment must hold a Human Tissue Authority storage licence if it holds the tissue for more than 48 hours. Tissue Establishments should inform hospitals if a graft is classified as Relevant Material, and ensure that the hospital has an appropriate storage licence if they intend to hold the graft for more than 48 hours.