HLA-A, -B and -DR antigen frequencies of the London Cord Blood Bank units differ from those found in established bone marrow donor registries

Patients requiring allogeneic stem cell transplantation who do not have an HLA-matched related donor can sometimes obtain an unrelated donor by searching volunteer registries. The majority of donors in the registries are Caucasoid, which results in a lower probability of a non-Caucasoid patient finding a suitable donor. Cord blood is increasingly used as a source of haematopoietic stem cells for allogeneic bone marrow reconstitution and so far the London Cord Blood Bank has banked almost 3000 cord blood units. An analysis of the first 1500 units banked showed that more than 30% of the London Cord Blood Bank units are derived from UK ethnic minorities compared with only 2% of individuals recruited locally for the British Bone Marrow Registry (BBMR). The HLA types found in these cord blood units reflect their ethnic diversity and include: HLA-A34, A36, A80, B75, B61, B53, B78, B81 and B82. The units stored by the London Cord Blood Bank show an HLA profile which differs considerably from that of locally typed adult volunteers for the BBMR panel and this should help to increase the chances of obtaining acceptably HLA-matched donors for patients from ethnic minorities. Bone Marrow Transplantation (2000) 25, 475-481.     

Development of a district Cord Blood Bank: a model for cord blood banking in the National Health Service

The Bristol Cord Blood Bank was established as a pilot project within existing health services to establish cost-effective recruitment, collection and processing suitable for use in the NHS should cord blood become a routine source of haemopoietic stem cells for transplantation in the UK. An important aim of the project was to evaluate the feasibility of establishing a midwifery-based collection network, thus utilising expertise already in place. Collection was performed on the delivery suite immediately after the placenta was delivered. The clinical experience of the midwife collector/counsellors allowed rapid pre-collection assessment of the condition of the cord and placenta. This prevented collection attempts from diseased or otherwise damaged placentas, leading to conservation of resources by preventing collection of most small volume donations. The bank was established within the National Blood Service, Bristol Centre to achieve Good Manufacturing Practice standards and ensure that processing was subject to the same stringency required for other sources of haemopoietic stem cells. Cord blood is an expensive resource. By utilising existing expertise in district Obstetric and National Blood Services, the Bristol Cord Blood Bank may serve as a model for health economic evaluation of cord blood banking of volunteer donations within the NHS.     

Maternal, neonatal and collection factors influencing the haematopoietic content of cord blood units

BACKGROUND AND OBJECTIVES: Umbilical cord blood (UCB) contains haematopoietic stem cells and can be used as an alternative to bone marrow transplantation in certain cases. Engraftment was dependent upon the haematopoietic progenitor cell content of the cord blood units. This study was designed to investigate the influence of obstetric, neonatal and collection factors on the volume and haematopoietic content of UCB donations. MATERIAL AND METHODS: A retrospective analysis of obstetric and neonatal factors was performed from 300 cord blood donations in Valencia Cord Blood Bank. Maternal, neonatal and collection factors influencing cord blood quality measured as volume, total nucleated cell count, CD34+ cells and colony-forming units (CFU) were analysed. RESULTS: Bigger babies produced cord blood units with larger volume, higher cells counts, CFU and CD34 cell counts. In the multivariate analysis, we found that both placental weight and mode of collection were predictor variables for total nucleated cell count, CD34 cells and CFU. CONCLUSION: Our study concludes that cord blood units must be collected before placental delivery and that birth weight, as an estimation of the placental weight, could be added to standard cord blood donors criteria in order to improve the bank efficiency.     

Variant Creutzfeldt-Jakob disease in Australian blood donors: estimation of risk and the impact of deferral strategies

BACKGROUND AND OBJECTIVES: In Australia, a policy of deferring donors who have lived in the UK for longer than 6 months between 1980 and 1996 has been instituted to reduce the theoretical risk of transmitting variant Creutzfeldt-Jakob disease (vCJD) through the blood supply. The objective of this report was to refine estimates of the possible risks and benefits of donor-deferral strategies that are aimed at avoiding transmission of vCJD. MATERIALS AND METHODS: Estimates of the effect of donor deferral on the blood supply in Australia were based on a 1998 survey of blood donors. The number of donations from donors potentially infected with vCJD and excluded by donor deferral was estimated based on published estimates of the size of the vCJD epidemic in the UK and assuming that the risk of vCJD in Australian blood donors was proportional to the time lived in the UK between 1980 and 1996. The possible increased number of blood donations that were infected with human immunodeficiency virus (HIV), hepatitis C virus (HCV) or hepatitis B virus (HBV) and made during a window period (as a result of increased donations from first-time donors) was estimated using published methods. RESULTS: A strategy of deferring donations in Australia from people who have lived in the UK for 6 months or longer, between 1980 and 1996, was estimated to result in exclusion of 5.3% of all blood donations, corresponding to 50 100 donations in 1998. It was estimated that the annual number of blood donations made by donors potentially infected with vCJD is 1.15 (range 0.02--31.1, based on the uncertainty in the UK prevalence estimate). Donor deferral was estimated to remove 0.92 (range 0.02--25.1) of these donations. Replacement of 33%, 50% and 100% of excluded donations by donations from first-time donors, was estimated to result in an increase of 0.0010, 0.0019 and 0.0044, respectively, of HIV-infected donations per year donated during the window period; in an increase of 0.021, 0.038 and 0.089, respectively, of HCV-infected donations per year; and in an increase of 0.18, 0.33 and 0.76, respectively, of HBV-infected donations per year. CONCLUSIONS: The large uncertainties involved in these analyses mean that estimates must be interpreted cautiously, but the data does suggest that donor deferral may exclude more donations from donors potentially infected with vCJD than the corresponding increase, caused by donor replacement, of window-period donations possibly infected with HIV, HCV or HBV.     

Experiences of the Dresdner Cord Blood Bank, supported by the Deutsche Knochenmarkspenderdatei

Allogeneic bone marrow and peripheral blood stem cell transplantation is the treatment of choice for some malignant hematologic diseases, marrow failure syndromes, and severe congenital immunodeficiency states. Since Gluckman et al reported in 1988 the first successful human leukocyte antigen (HLA)-matched sibling umbilical cord blood stem cell transplantation, it has been known that cord blood is a valuable source of hematopoietic stem cells. The Cord Blood Bank at the University Hospital of Dresden was founded in 1997 and started collecting, processing, and cryoconserving umbilical cord blood in August 1997. The cord blood bank is supported by the largest German donor registry: Deutsche Knochenmarkspenderdatei (DKMS) in Tubingen, Germany. With the informed consent of the mothers, the collection is performed in collaboration with six hospitals in Dresden, Berlin, and Bautzen. We routinely perform a volume reduction by centrifuging the blood bag and expressing the leukocyte-rich supernatant. Routinely, sterility, total nucleated cells (TNC), CD34+ cell count, HLA class I and II, ABO/Rh blood group, and colony-forming units are evaluated. The maternal blood is screened for anti-immunodeficiency virus (anti-HIV), anti-hepatitis C virus (anti-HCV), anti-hepatitis B surface antigen (HBsAg), anti-hepatitis B surface (anti-HBs), anti-hepatitis B core (anti-HBc), anticytomegalovirus (anti-CMV), and toxoplasmosis and with Treponema pallidum hemagglutination assay (TPHA). More than 1,000 cord blood units could be collected. Because of the required volume and cell count and because of sterility, 50% of the collected units had to be discharged. Our results are comparable with data of other cord blood banks: mean volume 79 mL; cell count after volume reduction-TNC, 7.16 x 10(8); mononucleated cells (MNC), 3.75 x 10(8); CD34+ cells, 1.95 x 10(6); colony-forming units (CFU), 67.1 x 10(4). To increase the pool of potential umbilical cord blood units and in order to evaluate the possibility for unrelated transplants, cryopreservation and banking of large numbers of cord bloods are necessary.     

Optimizing donor selection in a cord blood bank

OBJECTIVES: The main limitation factor for the wide use of umbilical cord blood (UCB) as a source of hematopoietic progenitor for transplantation is cell dose. One of the specific areas identified by some studies for improvement of UCB collection is donor selection. METHODS: Over a 3-mth period, 391 consecutive maternal-neonatal pairs were evaluated during the pre-partum period in the maternity ward at La Fe University Hospital (Valencia) by the Cord Blood Bank staff. Reasons for discarding umbilical cord blood donors and collected UCB units at the Cord Blood Bank in Valencia have been analysed. Obstetric factors influencing TNC content of 1300 collected UCB units have been determined, in order to establish obstetric criteria for cord blood donors selection in our geographic area. RESULTS: Only 32.5% of potential cord blood donors were refused. Among 1300 UCB collected, 506 (38.9%) were discarded before cryopreservation, mainly due to low cell counts. Multivariate analyses showed that the main significant factors influencing nucleated cell count were the weight of the placenta, sex of newborn and mode of collection. CONCLUSIONS: Our study shows that maternal medical histories must be completely reviewed by medical staff before collection of the UCB. Obstetrical factors influence cell content of UCB and could be added to standard cord blood donor criteria in order to improve the bank efficiency.     

Ethnicity, equity and public benefit: a critical evaluation of public umbilical cord blood banking in Australia

Over the past decade umbilical cord blood (UCB) has been increasingly used as a source of haematopoietic stem cells (HSCs) for patients who require a HSC transplant but do not have an HLA-matched donor. It was anticipated that using UCB as an alternative source of HSCs would increase the chance of finding a donor, particularly for the otherwise underrepresented ethnic minority groups. To evaluate the effectiveness of the Australian public UCB banks to increase the ethnic diversity of available HSC donations, this paper analyses the ethnic diversity of the Sydney Cord Blood Bank (SCBB), comparing this diversity to that of the Australian Bone Marrow Donor Registry (ABMDR). It also examines the ethnic diversity of those patients who, after requesting a haematopoietic stem cell transplantation in the 2-year period between 2003 and 2005, managed to find a suitably matched bone marrow or UCB donor. We show that the ethnic mix of donors to the SCBB has remained generally broad in source, is comparative to the Australian population, and is more diverse than the ABMDR. This, however, may still not be sufficient to substantially increase the likelihood of finding a donor for some ethnic minority groups.     

Tele-recruitment for Donor Retention

Blood transfusion services are the integral part of health care system and these services have safe blood transfusion as the major goal. Voluntary blood donation is the key to safe blood and this safety is further enhanced when the voluntary blood donors become repeat/regular donors. Retention of donors is therefore a very crucial strategy to ensure enhanced blood safety. Tele-recruitment is an effective medium of recruiting and more importantly retaining donors via means of telephone/Short Message Service. This study was carried out at a standalone blood bank during the period from January to December 2011 with objectives of donor retention, relationship management with the support of personnel with good communication skills, Donor data base, Integrated software and communication facility. For Initial 4 months there was no tele-recruiter, then for 2 months two tele-recruiter and for next 6 months three tele-recruiter were dedicated. Only impact of tele-recruitment on in-house donation was taken into consideration. 2,091 donors were recruited through tele-recruitment in this eight-month period. This was 63 % of in-house donations and 13 % of total donations. In other words out of every five in-house donations, three donations were from people contacted through tele-recruitment. Repeat voluntary blood donation is the safest donation. Tele-recruitment does this by converting ‘first-time’ donors into repeat/regular donors. Simple intervention like reminder calls on telephone can be highly effective tool to retain donors. Tele-recruitment helped the blood center establish relationships with individual donors, and, maybe, even the society at large. Tele-recruitment is a very low-cost model which can be easily replicated in all kind of blood banks, be it standalone, or a hospital based. Even the blood centers which are largely dependent on replacement donors can possibly have good results and convert replacement donors into repeat/regular voluntary blood donors.     

An overview of the Welsh bone marrow donor registry: 10 years of bone marrow donor provision

The Welsh Bone Marrow Donor Registry (WBMDR) is in its 11th year of operation and its 4th year as an International 'Hub' participating in Bone Marrow Donors Worldwide. It is operated by the Welsh Regional Tissue Typing Laboratory which is accredited by Clinical Pathology Accreditation (UK) Ltd, and the European Federation for Immunogenetics and, together with the Welsh Blood Service, its donor centre, is ISO 9001 Registered. The active donor panel of over 21 000 regular blood donors are all HLA-A, B, DR, DQ typed (over 95% to the split specificity level or higher). All HLA-DR, DQ and over 50% of HLA-A, B typing has been performed by DNA-based methods. CMV antibody status, now tested on all donors, is known on over 70% of subjects. The WBMDR has over 80% success at obtaining Confirmatory Typing samples and operates a rapid Expanded Typing service on stored donor material. It has provided 174 bone marrow donations (140 for UK and 34 for overseas patients), and 11 lymphocyte donations, since its inception in 1989.     

Motivations for donating blood and reasons why people lapse or never donate in Leeds, England: a 2001 questionnaire-based survey

Blood donors' motivations and reasons for lapsing and never donating were determined from a questionnaire completed by 489 adults (89 regular donors, 105 lapsed donors, 295 never donors) in Leeds, UK. The free text responses were classified according to themes that arose. Altruistic motivations including reciprocation and kinship towards family, friends, and unknowns were most numerous. Other motivations related to the NHS or National Blood Service, obligation, occupation, self-interest, convenience, peer-influence, health benefits, a rare blood group, donations being useful, a TV programme, or ethnicity. Reasons for non-donation were personal, medical, donation centre- or procedure-related, exclusions, and age-related. Suggestions are offered to increase the blood supply.     

Estimates of the frequency of HBV, HCV, and HIV infectious donations entering the blood supply in the United Kingdom, 1996 to 2003

Several new tests have been recently introduced by the United Kingdom Blood Services to improve safety. The frequency (or risk) of hepatitis B virus (HBV), hepatitis C virus (HCV) and HIV infectious donations entering the UK blood supply during 1996-2003 has been estimated. These years span the introduction of nucleic acid testing (NAT) for HCV, HIV combination antigen and antibody test and NAT for HIV. The frequency of an infectious donation entering the blood supply due to i) the window period, ii) assay failures and iii) human and technical errors in testing and processing, was estimated. The window period risk was estimated using the incidence of infection in donors and the length of the window period for tests in use, with an adjustment for atypical inter-donation intervals in seroconverting donors. The estimated frequency of infectious donations entering the blood supply during 1996-2003 was 1.66, 0.80 and 0.14 per million for HBV, HCV and HIV respectively. HCV NAT resulted in an over 95% fall in the risk of HCV. Current usage of HIV combined antibody-antigen tests and of HIV NAT reduced the estimated risk of HIV by 10%. Since 1996, the risk of transfusion-transmitted HBV, HCV and HIV infection in the UK has been lowered by several improvements to donation testing, although the absolute reduction in risk has been small. Vigilance for errors and the affects of donor selection may be as or more important than further reductions to window periods of tests for improving blood safety with respect to HBV, HCV and HIV.     

The Japan Marrow Donor Program, the Japan Cord Blood Bank Network and the Asia Blood and Marrow Transplant Registry

The annual number of hematopoietic stem cell transplants in Japan is about 3500, which are performed by more than 300 medical teams throughout the country. The Japan Marrow Donor Program (JMDP), initiated in 1991, has recruited 300,000 volunteer donors, accepted 20,000 patients and has facilitated more than 8000 unrelated bone marrow transplants. The Japan Cord Blood Bank Network (JCBN), which started in 1999, has collected 20,000 cord blood units and facilitated 4000 cord blood transplants up to now. To fulfill the requirement for HSCT, international collaborations as well as domestic efforts are considered to be important for the future. The Center for International Blood and Marrow Transplant Research (CIBMTR) and European Blood and Marrow Transplant Group (EBMT) initiated a movement to create a common clinical record form last winter and called on the Asia-Pacific Blood and Marrow Transplantation Group (APBMT) to join them. Globalization of patient and donor registration for HSCT has become realistic and this could contribute to both the further improvement of patient outcomes and to further donor safety.     

Allogeneic haemopoietic stem cell transplantation in children: what alternative donor should we choose when no matched sibling is available?

Allogeneic haemopoietic stem cell transplantation has provided curative therapy for life-threatening malignant and non-malignant diseases in children for over 40 years. Only 25% of children in whom an allograft is indicated have the ideal option of a human leucocyte antigen-identical sibling donor. Substantial advances in the use of alternative donors (unrelated volunteer donors, haploidentical family donors and unrelated umbilical cord blood donors) now make it possible for almost all children to benefit from this life-saving treatment. Each donor choice is associated with distinct advantages and disadvantages, which have greater or lesser importance in different diseases. We review the current status of alternative donor transplantation for haematological malignancies, primary immunodeficiencies, inherited metabolic disorders and bone marrow failure syndromes and outline the current UK consensus donor selection algorithms for these disease groups.     

Successful transplantation of HLA-matched and HLA-mismatched umbilical cord blood from unrelated donors: analysis of engraftment and acute graft-versus-host disease

To reduce the morbidity and mortality associated with unrelated donor bone marrow (BM) transplantation and potentially extend the pool of suitable donors, cryopreserved unrelated donor umbilical cord blood was considered as an alternate source of hematopoietic stem cells for transplantation. Patients with leukemia, BM failure syndrome, or inborn error of metabolism were eligible for a phase I clinical trial designed to estimate the risk of graft failure and severe acute graft-versus- host disease after transplantation of umbilical cord blood from unrelated donors. As of December 21, 1995, unrelated donor umbilical cord blood was used to reconstitute hematopoiesis in eighteen patients aged 0.1 to 21.3 years weighing 3.3 to 78.8 kg with acquired or congenital lympho-hematopoietic disorders or metabolic disease. Patients received either HLA-matched (n = 7) or HLA-1 to 3 antigen disparate (n = 11) grafts collected and evaluated by the New York Blood Center (New York, NY). The probability of engraftment after unrelated donor umbilical cord blood transplantation was 100% with no patient having late graft failure to date. The probability of grade III-IV acute graft-versus-host disease at 100 days was 11%. With a median follow-up of 6 months (range, 1.6 to 17 months); the probability of survival at 6 months is 65% in this high risk patient population. We conclude that cryopreserved umbilical cord blood from HLA-matched and mismatched unrelated donors is a sufficient source of transplantable hematopoietic stem cells with high probability of donor derived engraftment and low risk of refractory severe acute graft-versus-host disease. Limitations with regard to recipient size and degree of donor HLA disparity remain to be determined.     

Umbilical cord blood for unrelated bone marrow replacement; Asia bank and Japan cord blood bank network update

Cord blood offers many advantages including a high concentration of hematopoietic stem cells, a large number of potential donors, and ease of harvest. Furthermore, since there is no risk for either the mother or baby, few people refuse to donate. There is thought to be a low risk for virus contamination and also probably a low incidence and severity of GVHD. Cord blood can be obtained quickly without the assistance of a coordinator and one or 2 locus-mismatched HLA is usually acceptable. In Japan, there are 10 cord blood banks supported by the government. Between 1996 and June 2002, 9,500 units were registered with the Japan cord blood bank network (JCBBN). 630 units were delivered and most of these were transplanted. The status of registered cord blood units worldwide is shown. 59,081 units have been registered by NETCORD. The Japan cord blood bank network accounts for 13% of these units. I will discuss the Tokyo cord blood tank (TCBB). The bank at Tokyo, to which we belong, is one of the largest banks in Japan. We helped to establish Asia CORD in 2000 and have held annual conferences and meetings in Tokyo to exchange information. So far, China, Korea, Taiwan, Thailand, Viet Nam and Japan have participated. We accepted three trainees from the Ho Chi Minh City Blood Transfusion and Hematology Center for training in cord blood transplantation in May 2001. In January 2002, a patient with ALL received cord blood and was successfully engrafted at Ho Chi Minh City Blood Transfusion and Hematology Center. We present here the clinical outcome of these patients through Tokyo cord blood bank and Japan cord blood bank network. First, the number of CB units stored and registered at JCBBN and TCBB has increased rapidly over the past two years. Second, the survival rate of acute leukemia patients in release was significantly lower than that in patients in CR. Third, the engraftment rate in patients with metabolic disease (50%) was lower than that in patients with leukemia. Fourth, there was no significant difference in the incidence of acute GVHD greater than grade II between patients with a 1-locus and 2-locus mismatch. Finally, the incidence of acute GVHD was relatively low, and there were no deaths related to acute GVHD.     

Unusual adverse events following peripheral blood stem cell (PBSC) mobilisation using granulocyte colony stimulating factor (G-CSF) in healthy donors

Here, we describe two cases of severe pyogenic infection in healthy donors diagnosed immediately following stem cell mobilisation with G-CSF. In the first donor a painful perianal abscess and in the second one an apical abscess required surgical incision. The reported serious adverse events in the literature are reviewed and the potential pathophysiological role of G-CSF or GM-CSF in augmenting inflammatory processes is discussed. In the light of a rapidly increasing number of related and unrelated peripheral blood stem cell donations the need for more comprehensive donor work-up and follow-up for peripheral blood stem cell donors has to be considered. Bone Marrow Transplantation (2000) 26, 811-813.     

The current role of T cell depletion in paediatric stem cell transplantation

Haematopoeitic stem cell transplantation (HSCT) is a curative procedure for children with malignant and non‐malignant haematological disease as well as an expanding number of inherited disorders. Most patients lack a human leucocyte antigen‐matched related donor, making alternative donors, such as closely matched unrelated donors, unrelated umbilical cord blood donations and haploidentical donors, necessary choices. T cell depletion (TCD) has been employed for over 30 years to reduce the risk of graft‐versus‐host disease (GvHD) associated with non‐genoidentical HSCT. However, until recently overall survival had not improved with TCD due to increased rates of graft failure, disease relapse and delayed immune reconstitution. Recent advances in graft manipulation and reduced toxicity conditioning regimens have offered renewed hope, particularly for children undergoing haploidentical HSCT, where encouraging results have been achieved using negative depletion techniques to retain beneficial accessory cells, which speed immune reconstitution and reduce disease relapse. Translational work building on megadose CD34⁺ selected grafts, including pathogen‐specific immunotherapy, suicide gene therapy and other adoptive cellular immunotherapies, has also offered improved outcomes for such patients.     

Evidence that anti-HBc but not HBV DNA testing may prevent some HBV transmission by transfusion

Blood donor screening for antibody to hepatitis B core antigen (anti-HBc) implemented in some countries as a surrogate marker for non-A, non-B hepatitis has been superseded by anti-HCV screening. To assess the value of anti-HBc screening for the detection of hepatitis B surface antigen-negative blood donations that might contain infectious HBV, HBV genomic detection and recipient testing were used. Blood donations were screened and confirmed by multiple anti-HBc assays. Donations containing isolated anti-HBc and those with anti-hepatitis B surface antigen (anti-HBs) level < 0.1 IU/ml were tested for the presence of HBV DNA. Recipients of previous donations from the corresponding donors during the previous 5 years were traced and tested for markers of HBV infection. Of 103 869 donations screened, 586 (0.56%) were anti-HBc positive, two of which contained HBsAg, and 413 (0.4%) had protective (>/= 0.1 IU/ml) levels of anti-HBs. Anti-HBs < 0.1 IU/ml was found in 102 of these donations (0.1%) and isolated anti-HBc in 69 (0.07%). No donations with isolated anti-HBc were HBV DNA confirmed positive. Of 278 recipients of previous donations from 171 donors at risk of HBV carriage, 12 had markers of HBV infection. Six recipients had other identified risk factors. An association with blood transfusion was considered probable in two and possible in four recipients. None of the six corresponding donors had detectable HBV DNA 6-40 months after the implicated donation. The frequency of HBV transmission by chronic carriers negative for hepatitis B surface antigen was estimated in this study to be 1 in 52,000 donations (CI 0.3-7.8/100,000) from HBsAg-negative donors. Such HBV infectious donations may not be detected by DNA amplification.     

Set-up and routine use of a database of 10 555 genotyped blood donors to facilitate the screening of compatible blood components for alloimmunized patients

Background and Objectives  Large-scale genotyping of blood donors for red blood cell and platelet antigens has been predicted to replace phenotyping assays in the screening of compatible blood components for alloimmunized patients. Although several genotyping platforms have been described, novel procedures and processes are needed to perform genotyping efficiently and to maximize its benefits for blood banks.
Materials and Methods  Here we describe the processes and procedures developed to introduce large-scale genotyping in our routine operations.
Results  Preliminary cost–benefit analysis indicated that genotyping must target frequent blood donors (> 3 donations/year) to be efficiently used. A custom-designed computer application was developed to manage the whole project. It selects frequent donors among recent donations, prints coded labels to identify blood samples sent to the external genotyping laboratory, and stores genotyping results. It can search for donors compatible for any combination of the 22 genotyped antigens as well as consult the current inventory for the presence of the corresponding blood components. The phenotype of recovered components is confirmed by standard serology techniques prior to shipment to hospitals.
Conclusion  Since October 2007, 10 555 blood donors have been genotyped. The database is used on a regular basis to find compatible blood components with a genotype–phenotype concordance of 99·6%.     

Recommendations for a standard UK approach to incorporating umbilical cord blood into clinical transplantation practice: an update on cord blood unit selection,donor selection algorithms and conditioning protocols

Allogeneic haemopoietic stem cell transplantation offers a potentially curative treatment option for a wide range of life‐threatening malignant and non‐malignant disorders of the bone marrow and immune system in patients of all ages. With rapidly emerging advances in the use of alternative donors, such as mismatched unrelated, cord blood and haploidentical donors, it is now possible to find a potential donor for almost all patients in whom an allograft is indicated. Therefore, for any specific patient, the transplant physician may be faced with a myriad of potential choices, including decisions concerning which donor to prioritize where there is more than one, the optimal selection of specific umbilical cord blood units and which conditioning and graft‐versus‐host disease prophylactic schedule to use. Donor choice may be further complicated by other important factors, such as urgency of transplant, the presence of alloantibodies, the disease status (homozygosity or heterozygosity) of sibling donors affected by inherited disorders and the cytomegalovirus serostatus of patient and donor. We report UK consensus guidelines on the selection of umbilical cord blood units, the hierarchy of donor selection and the preferred conditioning regimens for umbilical cord blood transplantation, with a summary of rationale supporting these recommendations.