[Dynamic analysis of junctional sequences of T cell receptor (TCR) delta and gamma gene rearrangement in childhood with acute lymphoblastic leukemia].
OBJECTIVE
To explore the junctional sequence difference of T cell receptor delta and gamma gene rearrangement in childhood acute lymphoblastic leukemia (ALL) at diagnosis, complete remission (CR) and relapse.


METHODS
By using the T-vector molecular cloning and sequencing and polymerase chain reaction, the junctional sequences of TCRdeltaV-D and TCRgammaV-J were dynamically analyzed in 34 bone marrow samples of ALL.


RESULTS
The junctional sequence of TCR delta, gamma gene showed significant difference and regularity before and after remission and during relapsed periods. The sequence of TCRdeltaV-D were analyzed in 24 samples from ALL. Among them, the intact Vdelta2 and 5'Ddelta3 sequences were observed in 10 samples at diagnosis, of which 7 samples had T-->C mutation in Ddelta3 nonamer sequence. The deletions of rearranged Vdelta2, 5'Ddelta3 and Ddelta3 haptamer sequences were found in 11 complete remission (CR) samples with ALL, but none had T-->C mutation in Ddelta3 nonamer sequence. The deletion rate of Vdelta2 or Ddelta3 sequences and the T-->C mutation in Ddelta3 nonamer sequence were extremely differed between samples at diagnosis and in remission (calculate exact probabilities P = 0.001). The junctional rearrangement sequence of 5'Ddelta3 sequences tended to remain intact in 3 relapsed samples. The findings of TCRgammaV-J sequences were similar to that of TCRdeltaV-D in 10 ALL patients.


CONCLUSIONS
The difference of TCRdeltaV-D and TCRgammaV-J junctional sequences were related to the development, therapeutic effectiveness and outcome in ALL.
Lu
J
J
Institute of Pediatrics, Affiliated Hospital, Medical School of Qingdao University, Qingdao 266003, China.
Gu
R
R
Lei
K
K
Wang
X
X
Sun
L
L
Pang
X
X
Li
X
X
Dong
Z
Z
D002648:Child; D002675:Child, Preschool; D005260:Female; D016694:Gene Rearrangement, delta-Chain T-Cell Antigen Receptor; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000276:immunology*; D012008:Recurrence