Utilization of TREC and KREC quantification for the monitoring of early T- and B-cell neogenesis in adult patients after allogeneic hematopoietic stem cell transplantation

J Transl Med. 2013 Aug 14;11:188. doi: 10.1186/1479-5876-11-188.


Background: After hematopoietic stem cell transplantation (HSCT) T- and B-cell reconstitution from primary lymphoid organs are a prerequisite for an effective early lymphocyte reconstitution and a long-term survival for adult patients suffering from acute leukemia. Here, we asked whether quantification of T cell receptor excision circle, (TREC) and kappa-deleting recombination excision circle (KREC) before and within six month after allogeneic HSCT could be used to measure the thymic and bone marrow outputs in such patients.

Methods: We used a duplex real time PCR assay to quantify the absolute copy counts of TREC and KREC, and correlated the data with absolute cell counts of CD3+CD4+ T-cell and CD19+ B-cell subsets determined by flow cytometry, respectively.

Results: By comparing two recently proposed naïve T cell subsets, CD31+ naive and CD31- naive T cells, we found a better correlation for the CD31+ subset with TREC level post alloHSCT, in line with the assumption that it contained T cells recently derived from the thymus, indicating that TREC levels reflected real thymic de novo production. Transitional as well as naïve B cells highly correlated with KREC levels, which suggested an association of KREC levels with ongoing bone marrow B cell output. CD45RO+ memory T cells and CD27+ memory B cells were significantly less correlated with TREC and KREC recovery, respectively.

Conclusion: We conclude that simultaneous TREC/ KREC quantification is as a suitable and practicable method to monitor thymic and bone marrow output post alloHSCT in adult patients diagnosed with acute leukemia.

MeSH terms

  • Adult
  • B-Lymphocytes / metabolism*
  • DNA, Circular / metabolism*
  • Female
  • Flow Cytometry
  • Hematopoietic Stem Cell Transplantation*
  • Humans
  • Male
  • Middle Aged
  • Receptors, Antigen, T-Cell / metabolism*
  • T-Lymphocyte Subsets
  • T-Lymphocytes / metabolism*
  • Transplantation, Homologous


  • DNA, Circular
  • Receptors, Antigen, T-Cell