[Peripheral blood naive T cell level and its T cell receptor Vbeta repertoire usage profile in patients with chronic myelogenous leukemia].
OBJECTIVE
To analyze peripheral blood naive T cell level, its T cell receptor (TCR) Vbeta repertoire usage profile and clonality for evaluating the recent thymic output function and the expansion feature of TCR Vbeta subfamily T cells in patients with chronic myelogenous leukemia (CML).


METHODS
Quantitative detection of T-cell receptor excision DNA circles (TRECs) in peripheral blood mononuclear cells (PBMNC) from 20 cases of CML was preformed by real-time PCR (TaqMan) analysis, and TRECs-number in T-cells was calculated from peripheral blood CD3-positive cell rate. The expression and clonality analysis were detected by RT-PCR and Genescan technique in PBMNC from 14 out of the 20 patients. Nine normal individuals served as controls.


RESULTS
A dramatic reduction of TRECs value in patients with CML was detected as compared with that in normal controls. The mean value of TRECs was 0.06 +/- 0.16 copy/1000 CD3(+) cells in CML patients while 6.84 +/- 4.71 copies/1000 CD3(+) cells in normal controls (P < 0.01). The 1 - 12 Vbeta subfamilies were variably expressed in samples from 14 patients. Genescan analysis identified clonal expanded T cells of some Vbeta subfamily from 13 cases. Vbeta3, Vbeta10, Vbeta19, Vbeta21 and Vbeta22 subfamilies clonal T cells were more frequently seen.


CONCLUSIONS
There is a prominent reduction of recent thymic output naive T cells function in CML. The predominant usage and clonal expansion of TCR Vbeta subfamily T cells could be identified, indicating that CML patients have specific immune response to leukemia associated antigen, in spite of their T cell immunodeficiency.
Geng
Su-xia
SX
Institute of Hematology, Medical College, Jinan University, Guangzhou 510632, China.
Li
Yang-qiu
YQ
Chen
Shao-hua
SH
Yang
Li-jian
LJ
Yin
Qing-song
QS
Wu
Xiu-li
XL
Zhang
Xue-li
XL
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D015973:Gene Expression Regulation, Leukemic; D019674:Genes, T-Cell Receptor beta / Q000235:genetics*; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000097:blood / Q000235:genetics* / Q000276:immunology; D008297:Male; D011948:Receptors, Antigen, T-Cell / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology
D011948:Receptors, Antigen, T-Cell