Rapid detection of clonal expansion of T-cell receptor-beta gene in patients with HBV using the real-time PCR with DNA melting curve analysis.

Aim: The gene melting spectral pattern (GMSP) of PCR products from 24 T-cell receptor beta chain variable (TCRBV) gene families was developed to determine sequence bias and feature of TCRBV CDR3 gene family.
Methods: The assay was based on reverse transcript quantitative polymerase chain reaction and their DNA melting curves.
Results: We discovered that the relatively conserved amino acid sequences X-Q and X-G are present in TCRBV CDR3 from patients with HBV. Further, the X of the X-Q motif is preferentially E (glutamic acid), P (proline) or T (threonine) when accompanied by the BJ2.7, BJ1.5, or BJ2.3, respectively. The frequency of sequence bias in the TCRBV gene family showed a positive correlation with the T cell receptor excision circles (TRECs) content, and an inverse correlation with the HBV DNA loading.
Conclusion: These results suggest that the GMSP assay could be used to monitor the features of TCRBV gene distribution quickly, and facilitate the further study of HBV-specific T cell in patients with HBV.