Alan Lankester

Directed Sibling Cord Blood Banking for Transplantation: The 10-Year Experience in the National Blood Service in England

Umbilical cord blood (UCB) is an important source of hematopoietic stem cells for transplantation. Although UCB is often collected from unrelated donors, directed umbilical cord blood (DCB) from sibling donors also provides an important source of UCB for transplantation. This report summarizes the experience in collection, testing, storage, and transplantation of DCB units by the National Blood Service for England and North Wales over 10 years. Eligibility for collection was based on an existing sibling suffering from a disease that may be treated by stem cell transplantation or a family history that could result in the birth of a sibling with a disease that could be treated by stem cell transplantation. Collections were made on the provision that the siblings clinician was willing to financially support the collection and to take responsibility for medical review of the mother and potential recipient. Given the high investment in UCB banking and the introduction of new regulations and mandatory licensing under the European Union Tissues and Cells Directive and those proposed in the U.S., this report details the procedures that we have used for DCB donations, the outcome data where donations have been used for transplantation, and it provides some timely recommendations for best practices.

Early lymphocyte recovery is an important determinant of outcome following allogeneic transplantation with CD34+ selected graft and limited T-cell addback

Summary:We evaluated the outcome of 29 patients (age 22–60 years), who received a CD34+selected related (n=16) or unrelated graft (n=13) with limited T-cell addback (TCAB) (median 5.9 × 104/kg) following full-intensity conditioning for haematological malignancies. In all, 16 patients (55%) had either advanced disease or previous transplants. The cumulative incidences of grade 2–4 acute GVHD were 15.4 and 19.2% and that for chronic extensive GVHD were 35 and 37% in related and unrelated graft recipients, respectively. The strongest predictor of nonrelapse mortality and overall survival was the absolute lymphocyte count (ALC) at 30 days; patients with ALC<0.35 × 109/l having an NRM and OS of 59.2 and 24.7%, compared to 10 and 90% in those with a higher ALC. Patients with acute leukaemia had poorer survival and this was associated with a lower ALC as well. Thus, TCAB with a CD34+ selected graft resulted in a comparable outcome in both older and younger patients, but the survival was strongly influenced by early lymphocyte recovery.

Standards for the Terminology and Labeling of Cellular Therapy Products

T hese standards have been developed through the co-operative endeavor of the following organizations: AABB, American Society for Blood and Marrow Transplantation (ASBMT), American Society for Apheresis (ASFA), European Group for Blood and Marrow Transplantation (EBMT), Foundation for the Accreditation of Cellular Therapy (FACT), ICCBBA, International Society of Blood Transfusion (ISBT), International Society for Cellular Therapy (ISCT), ISCT Europe, Joint Accreditation Committee of ISCT and EBMT (JACIE), National Marrow Donor Program (NMDP), and the World Marrow Donor Association (WMDA). The use of standard terminology will help to ensure a common understanding of product definitions. The labeling standard, supported by the ISBT 128 information system, will ensure unique global identification of cellular therapy products, an international reference table for product descriptions, and label design that is consistent worldwide. The organizations supporting these standards believe that their adoption will significantly improve the quality, safety, and traceability of cellular therapy products. In developing the terminology standard the Advisory Group recognized that the frequent movement of cellular therapy products between countries (and continents) required a consistent use of terminology between ISBT 128 and other published standards (e.g., Circular of Information, AABB, FACT, JACIE, Netcord). The Advisory Group has attempted to achieve these aims by removing complexity and redundancy from the coding system wherever possible and, by wide consultation, agreeing to terminology acceptable to all for inclusion in future publication of their standards and guidance. TERMINOLOGY STANDARD

Double T cell depletion of bone marrow using sequential positive and negative cell immunoaffinity or CD34 + cell selection followed by Campath-1M; effect on CD34 + cells and progenitor cell recoveries

An advantage of CD34+ cell selection over antibody purging is that a component allograft is produced comprising a stem cell enriched and an unadsorbed fraction, the latter containing T cells which may be used for post-transplant immunotherapy. Initial reports with PBSC allografts suggested that T cell depletion (TCD) by CD34+ cell selection and post-graft cyclosporin A ± methotrexate was insufficient prophylaxis against acute GVHD. We compared sequential TCD (of a CD34+ cell-selected fraction) using a second (CD2) immunoaffinity step or Campath-1M monoclonal antibody and complement. Since a high stem cell ‘dose’ enhances engraftment across HLA barriers and improves overall post-transplant outcome, the recovery of CD34+ cells and progenitors were assessed. Sequential positive (CD34+) and negative (CD2+) immunoaffinity selection resulted in a 3.4 log depletion of T cells as compared to a 4.05 log depletion when CD34+ cell selection was followed by Campath-1M treatment. Recoveries of CD34+ cells, CFU-GM and BFU-E following double depletion using CD34+ cell selection plus CD2+ cell depletion were 28, 25 and 17% as compared to 20, 18 and 16% when CD34+ cells were treated with Campath-1M. The unadsorbed fraction contained 85% of the original T cells, from which donor leukocyte infusions in the range of 105 to 107 CD3+ cells per kg body weight of the recipient were harvested. Despite the advantages of component allografts, the loss of stem/progenitor cells may restrict sequential TCD steps unless single BM harvests are supplemented and/or replaced with mobilised PBSCs.

Terminology and labeling of cellular products: 1. Standards.

The International Cellular Therapy Coding and Labeling Advisory Group was established to address the growing need for standardization of terminology and labeling for cellular therapy products as a result of increasing international transfer of these products. This paper presents new standards for terminology and labeling. These standards have been developed through a consultative process and are supported by key professional and accreditation bodies. By using these standards, together with the unique donation identification numbers and international product reference tables provided by the International Society of Blood Transfusion (ISBT) 128 Standard, consistency and traceability can be assured at the global level. A companion paper provides guidance on the implementation of the ISBT 128 system.