title: Reduced levels of recent thymic emigrants in acute myeloid leukemia patients.
abstract: BACKGROUND
  T cell immunodeficiency is a common feature in cancer patients, which may relate to initiation and development of tumor. Our previous study showed skewed expression of T cell receptor beta variable region (TRBV) subfamilies and clonal expansion of T cells in leukemia patients. In the present study, in order to further characterize the T cell immunity in acute myeloid leukemia (AML) patients, the level of recent thymic emigrants (RTE) was analyzed.
  
  
  METHODS
  Quantitative analysis of signal joint T cell recombination excision circles (deltaRec-psiJalpha sjTRECs) was performed in peripheral blood mononuclear cells (PBMCs) by real-time PCR (TaqMan), and the analysis of 23 TRBV-BD1 sjTRECs was performed by semi-nested PCR. Eighty-eight cases with AML were selected for this study; ten AML cases in complete remission (AML-CR) and 38 healthy individuals served as controls.
  
  
  RESULTS
  The levels of deltaRec-psiJalpha sjTRECs in PBMCs and CD3+ T cells were significantly decreased in AML patients, compared with healthy individuals and in patients in completive remission. Also the frequency of 23 TRBV-BD1 sjTRECs, and the number of detectable TRBV subfamily sjTRECs were significantly lower in AML patients than in healthy individuals. Moreover, the sjTRECs numbers and the frequency of TRBV-BD1 sjTRECs showed a progressive linear decline with age in AML patients.
  
  
  CONCLUSIONS
  The decreased numbers of universal (deltaRec-psiJalpha) and family-specific (TRBV-BD1) sjTRECs indicate that the severe T cell immunodeficiency in AML patients is associated with reduced levels of recent thymic emigrants. In patients achieving complete remission both sjTREC counts return to normal values indicating the recovery of thymic function. Better understanding of the mechanisms underlying persistent immunodeficiency in leukemia patients may lead to novel treatment strategies to enhance immune competence.
authors.affiliation: Institute of Hematology, Medical College, Jinan University, 510632 Guangzhou, China. yangqiuli@hotmail.com
authors.forename: Yangqiu
authors.initials: Y
authors.lastname: Li
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Yin
authors.forename: Lijian
authors.initials: L
authors.lastname: Yang
authors.forename: Shaohua
authors.initials: S
authors.lastname: Chen
authors.forename: Suxia
authors.initials: S
authors.lastname: Geng
authors.forename: Xiuli
authors.initials: X
authors.lastname: Wu
authors.forename: Liye
authors.initials: L
authors.lastname: Zhong
authors.forename: Christian A
authors.initials: CA
authors.lastname: Schmidt
authors.forename: Grzegorz K
authors.initials: GK
authors.lastname: Przybylski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002465:Cell Movement / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D005260:Female; D005787:Gene Frequency; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology*; D055815:Young Adult
chemical_list: D016693:Receptors, Antigen, T-Cell, alpha-beta