Regulation of dendritic cells and white blood cells other than granulocytes

The Human Tissue (Quality and Safety for Human Application) Regulations 2007 (as amended) (the Q&S Regulations) and the Blood Safety and Quality Regulations 2005 define ‘blood component’ as ‘a therapeutic constituent of human blood (red cells, white cells, platelets and plasma) that can be prepared by various methods’.

The term ‘therapeutic constituent of human blood’ is not defined further in the aforementioned legislation. 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, dendritic cells are generated from both haematopoietic stem cells and monocytes, the former of which clearly fall into the remit of the Q&S Regulations.

In consideration of these factors, the HTA includes dendritic cells and/or white blood cells (other than granulocytes) in the definition of tissues and cells in the Q&S Regulations and therefore they fall under the regulatory remit of the HTA.