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Blood First Edition Paper, prepublished online November 4, 2009; DOI 10.1182/blood-2009-08-235895. This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Rights and Permissions Citing Articles Citing Articles via CrossRef Google Scholar Articles by Samarasinghe, S. Articles by Amrolia, P. J. PubMed PubMed Citation Articles by Samarasinghe, S. Articles by Amrolia, P. J. Social Bookmarking                   What's this?  Previous Article  |  Next Article  Submitted August 6, 2009; accepted October 5, 2009. Functional characterization of alloreactive T-cells identifies CD25 and CD71 as optimal targets for a clinically applicable allodepletion strategy Sujith Samarasinghe1, Christoph Mancao1, Martin Pule2, Niga Nawroly3, Helen Karlsson1, Jennifer Brewin1, Peter Openshaw3, H. Bobby Gaspar1, Paul Veys4 and Persis J. Amrolia4,5 1 Department of Molecular Immunology, Institute of Child Health, London, United Kingdom; 2 Department of Haematology, University College Hospital, London, United Kingdom; 3 National Heart and Lung Institute, St. Mary's Hospital, Imperial College, London, United Kingdom; 4 Department of Bone Marrow Transplantation, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom * Corresponding author; email: amrolp1{at}gosh.nhs.uk Abstract Immunotherapy with allodepleted donor T-cells (ADTs) improves immunity after T-cell depleted SCT, but infection/relapse remain problematic. To refine this approach, we characterized the expression of surface markers/cytokines on proliferating alloreactive T-cells (ATs). CD25 was expressed on 83 % of CFSE-dim ATs, confirming this as an excellent target for allodepletion. 70 % of CD25-ve ATs expressed CD71 (transferrin receptor), identifying this as a novel marker to target ATs persisting after CD25 depletion. Comparison of residual alloreactivity after combined CD25/71 vs. CD25 immunomagnetic depletion showed enhanced depletion of alloreactivity to host with CD25/71 depletion in both 2o MLRs (p < 0.01) and IFN- ELISPOT assays (p < 0.05) with no effect on 3rd party responses. In pentamer/IFN- ELISPOT assays, anti-viral responses to CMV, EBV and adenovirus were preserved after CD25/71 allodepletion. CD25/71 ADTs can be redirected to recognize leukemic targets through lentiviral transfer of a chimeric CD19 TCR. Finally, we have established conditions for clinically applicable CD25/71 allodepletion under Good Manufacturing Practice conditions, resulting in highly effective, reproducible and selective depletion of ATs (median residual alloreactivity to host in 2o MLR 0.39% vs to 3rd party 62%, n=5). This strategy enables further clinical studies of adoptive immunotherapy with larger doses of ADTs to enhance immune reconstitution after T-cell depleted SCT. CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

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