Access through your institution Buy or subscribe > _The human understanding when it has once adopted an opinion (either > as being the received opinion or as being agreeable to itself)

 draws > all things else to support and agree with it. And though there be a > greater number and weight of instances to be found on the other > side, yet these it either neglects 

and despises, or else by some > distinction sets aside and rejects, in order that by this great and > pernicious predetermination the authority of its former conclusions > may 

remain inviolate._ > Sir Francis Bacon, _Novum Organum_ 1620 Aphorism 46 _The human understanding when it has once adopted an opinion (either as being the received opinion or as being

inviolate._ This is a preview of subscription content, access via your institution ACCESS OPTIONS Access through your institution Subscribe to this journal Receive 12 print issues and online

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H, Szer J, Gratwohl M, Aljurf M, Atsuta Y _et al_. Hematopoietic stem cell transplantation activity worldwide in 2012 and a SWOT analysis of the Worldwide Network for Blood and Marrow

Transplantation Group including the global survey. _Bone Marrow Transplant_ 2016; 51: 778–785. Article  CAS  Google Scholar  * Passweg JR, Baldomero H, Bader P, Bonini C, Cesaro S, Dreger P

_et al_. Hematopoietic SCT in Europe 2013: recent trends in the use of alternative donors showing more haploidentical donors but fewer cord blood transplants. _Bone Marrow Transplant_ 2015;

50: 476–482. Article  CAS  Google Scholar  * Terakura S, Atsuta Y, Tsukada N, Kobayashi T, Tanaka M, Kanda J _et al_. Comparison of outcomes of 8/8 and 7/8 allele–matched unrelated bone

marrow transplantation and single-unit cord blood transplantation in adults with acute leukemia. _Biol Blood Marrow Transplant_ 2016; 22: 330–338. Article  Google Scholar  * Ruggeri A,

Labopin M, Sanz G, Piemontese S, Arcese W, Bacigalupo A _et al_. Comparison of outcomes after unrelated cord blood and unmanipulated haploidentical stem cell transplantation in adults with

acute leukemia. _Leukemia_ 2015; 29: 1891–1900. Article  CAS  Google Scholar  * Eapen M, Rocha V, Sanz GF, Scaradavou A, Zhang M-J, Arcese W _et al_. Effect of graft source on unrelated

donor haemopoietic stem-cell transplantation in adults with acute leukaemia: a retrospective analysis. _Lancet Oncol_ 2010; 11: 653–660. Article  Google Scholar  * Barker JN, Weisdorf DJ,

DeFor TE, Blazar BR, McGlave PB, Miller JS _et al_. Transplantation of 2 partially HLA-matched umbilical cord blood units to enhance engraftment in adults with hematologic malignancy.

_Blood_ 2005; 105: 1343–1347. Article  CAS  Google Scholar  * Gale RP, Lazarus HM . Engraftment syndrome, the emperor's new clothes and the artist formerly known as prince. _Bone Marrow

Transplant_ 2015; 50: 483–484. Article  CAS  Google Scholar  * Otegbeye F, Gale RP, Lazarus HM . Autologous GvHD? _Bone Marrow Transplant_ 2014; 49: 1349–1351. Article  CAS  Google Scholar

  * Oliver DCK, Milano F, Gammill H, Gentil C, Kanaan SB, Allen J _et al_. Persistence of the losing unit following double umbilical cord blood transplant: finding the unseen. _Blood_ 2015;

126: 3109–3109. Google Scholar  * Verneris MR, Brunstein CG, Barker J, MacMillan ML, DeFor T, McKenna DH _et al_. Relapse risk after umbilical cord blood transplantation: enhanced

graft-versus-leukemia effect in recipients of 2 units. _Blood_ 2009; 114: 4293–4299. Article  CAS  Google Scholar  * Brunstein CG, Gutman JA, Weisdorf DJ, Woolfrey AE, Defor TE, Gooley TA

_et al_. Allogeneic hematopoietic cell transplantation for hematologic malignancy: relative risks and benefits of double umbilical cord blood. _Blood_ 2010; 116: 4693–4699. Article  CAS 

Google Scholar  * Brunstein CG, Fuchs EJ, Carter SL, Karanes C, Costa LJ, Wu J _et al_. Alternative donor transplantation after reduced intensity conditioning: results of parallel phase 2

trials using partially HLA-mismatched related bone marrow or unrelated double umbilical cord blood grafts. _Blood_ 2011; 118: 282–288. Article  CAS  Google Scholar  * Scaradavou A, Brunstein

CG, Eapen M, Le-Rademacher J, Barker JN, Chao N _et al_. Double unit grafts successfully extend the application of umbilical cord blood transplantation in adults with acute leukemia.

_Blood_ 2013; 121: 752–758. Article  CAS  Google Scholar  * Ruggeri A, Sanz G, Bittencourt H, Sanz J, Rambaldi A, Volt F _et al_. Comparison of outcomes after single or double cord blood

transplantation in adults with acute leukemia using different types of myeloablative conditioning regimen, a retrospective study on behalf of Eurocord and the Acute Leukemia Working Party of

EBMT. _Leukemia_ 2014; 28: 779–786. Article  CAS  Google Scholar  * Sanz J, Wagner JE, Sanz MA, DeFor T, Montesinos P, Bachanova V _et al_. Myeloablative cord blood transplantation in

adults with acute leukemia: comparison of two different transplant platforms. _Biol Blood Marrow Transplant_ 2013; 19: 1725–1730. Article  Google Scholar  * Wagner JE Jr, Eapen M, Carter S,

Wang Y, Schultz KR, Wall DA _et al_. One-unit versus two-unit cord-blood transplantation for hematologic cancers. _N Engl J Med_ 2014; 371: 1685–1694. Article  CAS  Google Scholar  * Michel

G, Galambrun C, Sirvent A, Pochon C, Bruno B, Jubert C _et al_. Single-versus double-unit cord blood transplantation for children and young adults with acute leukemia or myelodysplastic

syndrome. _Blood_ 2016; 127: 3450–3457. Article  CAS  Google Scholar  * MacMillan ML, Weisdorf DJ, Brunstein CG, Cao Q, Defor TE, Verneris MR _et al_. Acute graft-versus-host disease after

unrelated donor umbilical cord blood transplantation: analysis of risk factors. _Blood_ 2009; 113: 2410–2415. Article  CAS  Google Scholar  * Shoulars K, Noldner P, Troy JD, Cheatham L,

Parrish A, Page K _et al_. Development and validation of a rapid, aldehyde dehydrogenase bright-based cord blood potency assay. _Blood_ 2016; 127: 2346–2354. Article  CAS  Google Scholar  *

Nadler SB, Hidalgo JH, Bloch T . Prediction of blood volume in normal human adults. _Surgery_ 1962; 51: 224–232. PubMed  Google Scholar  * Hellman S, Botnick LE, Hannon EC, Vigneulle RM .

Proliferative capacity of murine hematopoietic stem cells. _Proc Natl Acad Sci USA_ 1978; 75: 490–494. Article  CAS  Google Scholar  * Ogden DA, Mickliem HS . The fate of serially

transplanted bone marrow cell populations from young and old donors. _Transplantation_ 1976; 22: 287–293. Article  CAS  Google Scholar  * Koller PC, Doak SM . Serial transfer of donor marrow

in radiation mouse chimaeras. _Int J Radiat Biol_ 1960; 2: 1–7. CAS  Google Scholar  * Caracappa PF, Chao TCE, Xu XG . A study of predicted bone marrow distribution on calculated marrow

dose from external radiation exposures using two sets of image data for the same individual. _Health Phys_ 2009; 96: 661–674. Article  CAS  Google Scholar  * Jones RJ, Celano P, Sharkis SJ,

Sensenbrenner LL . Two phases of engraftment established by serial bone marrow transplantation in mice. _Blood_ 1989; 73: 397–401. CAS  PubMed  Google Scholar  * Jordan CT, Lemischka IR .

Clonal and systemic analysis of long-term hematopoiesis in the mouse. _Genes Dev_ 1990; 4: 220–232. Article  CAS  Google Scholar  * Guenechea G, Gan OI, Dorrell C, Dick JE . Distinct classes

of human stem cells that differ in proliferative and self-renewal potential. _Nat Immunol_ 2001; 2: 75–82. Article  CAS  Google Scholar  * Heslop HE, Rooney CM, Rill DR, Krance RA, Brenner

MK . Use of gene marking in bone marrow transplantation. _Cancer Detect Prev_ 1996; 20: 108–113. CAS  PubMed  Google Scholar  * Rill DR, Moen RC, Buschle M, Bartholomew C, Foreman NK, Mirro

JJ _et al_. An approach for the analysis of relapse and marrow reconstitution after autologous marrow transplantation using retrovirus-mediated gene transfer. _Blood_ 1992; 79: 2694–2700.

CAS  PubMed  Google Scholar  * Baranov A, Gale RP, Guskova A, Piatkin E, Selidovkin G, Muravyova L _et al_. Bone marrow transplantation after the Chernobyl nuclear accident. _N Engl J Med_

1989; 321: 205–212. Article  CAS  Google Scholar  * Harris JE, Ford CE, Barnes DW, Evans EP . Evidence from parabiosis for an afferent stream of cells. _Nature_ 1964; 201: 886–887. Article 

CAS  Google Scholar  * Kamran P, Sereti K-I, Zhao P, Ali SR, Weissman IL, Ardehali R . Parabiosis in mice: a detailed protocol. _J Vis Exp_ 2013: (80): e50556, doi:10.3791/50556. * Till JE,

McCulloch EA . The ‘f-factor’ of the spleen-colony assay for hemopoietic stem cells. _Ser Haematol_ 1972; 5: 15–21. CAS  PubMed  Google Scholar  * Dumenil D, Lauret E, Frindel E . Effects of

various treatments of CFU-S seeding efficiency in mice. _Exp Hematol_ 1984; 12: 749–752. CAS  PubMed  Google Scholar  * Coggle JE, Gordon MY . Quantitative measurements on the haemopoietic

systems of three strains of mice. _Exp Hematol_ 1975; 3: 181–186. CAS  PubMed  Google Scholar  * Visser JW, Bauman JG, Mulder AH, Eliason JF, de Leeuw AM . Isolation of murine pluripotent

hemopoietic stem cells. _J Exp Med_ 1984; 159: 1576–1590. Article  CAS  Google Scholar  * Milano F, Gooley T, Wood B, Woolfrey A, Flowers ME, Doney K _et al_. Cord-blood transplantation in

patients with minimal residual disease. _N Engl J Med._ 2016; 375: 944–953. Article  Google Scholar  * Thompson PA, Rezvani K, Hosing CM, Oran B, Olson AL, Popat UR _et al_. Umbilical cord

blood graft engineering: challenges and opportunities. _Bone Marrow Transplant_ 2015; 50 (Suppl 2): S55–S62. Article  Google Scholar  * Norkin M, Lazarus HM, Wingard JR . Umbilical cord

blood graft enhancement strategies: has the time come to move these into the clinic? _Bone Marrow Transplant_ 2013; 48: 884–889. Article  CAS  Google Scholar  * Butler S . Hudibras. 1678.

Part III, Canto iii, lines 547–550. Download references ACKNOWLEDGEMENTS Profs. Hillard Lazarus (Case Western Reserve Univ.), Joanne Kurtzberg (Duke University), Claudio Brunstein (Univ.

Michigan), Hal Broxmeyer (Indiana Univ.), Yair Reisner (Weizmann Inst.) and Elaine Gluckman (Hospital St. Louis) kindly reviewed the typescript and contributed many interesting comments and

good ideas as did Dr. Roni Shouval (Tel Aviv Univ.). RPG acknowledges support from the National Institute of Health Research (NIHR) Biomedical Research Centre funding scheme. AUTHOR

INFORMATION AUTHORS AND AFFILIATIONS * Department of Hematology, Hospital Universitari i Politècnic La Fe, Valencia, Spain J Sanz * Division of Experimental Medicine, Department of Medicine,

Haematology Research Centre, Imperial College London, London, UK R P Gale Authors * J Sanz View author publications You can also search for this author inPubMed Google Scholar * R P Gale

View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to J Sanz. ETHICS DECLARATIONS COMPETING INTERESTS The authors

declare no conflict of interest. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Sanz, J., Gale, R. One or two umbilical cord blood cell units? _Caveat

emptor_. _Bone Marrow Transplant_ 52, 341–343 (2017). https://doi.org/10.1038/bmt.2016.277 Download citation * Received: 20 July 2016 * Accepted: 21 July 2016 * Published: 09 January 2017 *

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