OBJECTIVE

Successful allogeneic hematopoietic stem cell transplantation (HSCT) requires reconstitution normal T-cell immunity. Measurement of T-cell receptor excision circles (TRECs) and T-cell receptor beta (TCRBV) CDR3 repertoire is a means of quantifying recent thymic T-cell production and reflecting antigen-specific T-cell clones proliferation.

METHODS

We used real-time quantitative PCR to detect TRECs from 43 Chinese patients who underwent three kind of allo-HSCT without T-cell depletion. RT-PCR was performed to amplify 24 subfamily genes of TCRBV in 24 patients of them.

RESULTS

For haploidentical-D group, the TRECs numbers were lower up to 24 months. For matched-sibling donor (MSD) group, the recovery of TRECs was faster than those of other two groups. TRECs values in matched-unrelated donor (MUD) were in the middle. During 2-19 months after transplantation, there were 6-16 BV subfamilies expressed and 33-48% of them were polyclones. The usage rate of TCRBV and percentage of polyclones in haploidentical-D were less than those of other two groups. Twenty-three CDR3 molecules were obtained from nine patients who were potentially associated with GVHD or CMV infection.

CONCLUSIONS

Analyzing the changes of TCRBV repertoire and measuring TRECs during immune reconstitution would be useful to determine the host's current immune status and ability of T-cell immune reconstitution and also to find antigen-specific T-cell clones in the three kinds of HSCT.