Issued 15 February 2010
The Human Tissue Authority (HTA) has received a number of enquiries relating to the use of dendritic cells and certain types of white blood cells in a variety of therapeutic treatments. Clarification was needed on whether these cells would be regulated within the scope of the:
- Human Tissue (Quality and Safety for Human Application) Regulations 2007 (the Quality and Safety Regulations), which implement the European Union Tissues and Cells Directives; or
- the Blood Safety and Quality Regulations 2005, which implement the European Union Blood Directives.
Both sets of legislation define ‘blood component’ as ‘a therapeutic constituent of human blood (red cells, white cells, platelets and plasma) that can be prepared by various methods’, however the term ‘therapeutic constituent of human blood’ was not defined further. Consultation between the HTA and the Medicines and Healthcare products Regulatory Agency (MHRA) have interpreted a ‘therapeutic constituent of human blood’ to refer to an integral component of blood whose biological action takes place within the blood itself.
Functionally, dendritic cells have an immunological role in the human body and can be said to be excluded as a ‘therapeutic constituent of human blood’ as their presence is not essential to the function of blood in the human body. Additionally, the MHRA have suggested dendritic cells are generated from both haematopoietic stem cells and monocytes, the former of which clearly fall into the remit of the European Union Tissues and Cells Directives.
In consideration of these factors, the HTA considers dendritic cells and/or white blood cells (other than granulocytes) to be included in the definition of tissues and cells in the Quality and Safety Regulations and therefore fall under the regulatory remit of the HTA.