Cell Source and Apheresis

Abstract

AbstractApheresis involves the separation of whole blood into its component layers via the use of an automated blood cell separator machine and the process of continuous flow centrifugation. This allows for the isolation and collection of a variety of blood cells, including monocytes, lymphocytes, CD34 positive cells and dendritic cells, whilst simultaneously returning the other blood components back to the donor.The transplantation of haemopoietic stem cells to facilitate the treatment of a variety of haematological and non-haematological diseases is well established (BSBMTCT, 2022) (https://bsbmtct.org/indications-table—accessed Oct 2022).Peripheral blood stem cells have largely replaced harvested bone marrow-derived stem cells in both autologous and allogeneic transplant settings. Collection of peripheral blood stem cells generally yields a purer, less contaminated and more consistent product with a greater CD34 positive cell dose when compared to those harvested from the bone marrow. Thus shortening engraftment time, limiting infection risks and potentially enhancing the graft versus leukaemia effect in the allogeneic patient. Umbilical cord blood (UCB) provides a further stem cell source, which may be used in allogenic transplantation if appropriate.In recent years the ability to isolate blood-derived mononuclear cells via apheresis has been instrumental in the development of individually targeted, patient -specific immunotherapies, most notably Chimeric Antigen Receptor (CAR) T cell therapy. These type of cell collections are rapidly becoming a routine activity for many collection facilities.Successful collection of cellular blood products via apheresis has its challenges and is influenced by a multitude of variables, including patient’s clinical condition, vascular access, timing of collection, mobilisation regimes, institutional capacity, staff experience and regulations and accreditations.Apheresis and Bone Marrow collection facility accreditation by FACT-JACIE (2021) requires compliance and rigorous validation of standards in relation to all collection, processing, storage, distribution and infusion activities.In 2018 FACT-JACIE incorporated the administration of immune effector cells (IEC) into the scope of accreditation standards, which describes that additional training, policies for patient treatment, management of associated toxicities and maintenance of product chain of identity, additional outcome and follow-up reporting to relevant bodies are also an important requisite to fulfil compliance.