[Restricted usage of repertoire of T-cell receptor V beta in Chinese asthmatics].

OBJECTIVE

To investigate the association of restricted usage of repertoire of T cell receptor V beta (TCR V beta) with asthma.

METHODS

In 36 Chinese asthmatics, peripheral blood TCR V beta was studied by means of fluorescein-labeled RT-PCR as well as genescan and genotype software analysis. The clonality of the predominant usage T cell receptors was analyzed by denaturing gel electrophoresis and single strand conformation polymorphism (SSCP) by using genescan analysis (with 377 ABI DNA sequencer).

RESULTS

The number of cases predominantly using TCRV beta 8 gene families in asthmatics and those allergy to house dust mite (HDM) was significantly higher than that of normal controls (P = 0.0230, 0.0147), and so the TCR V beta 5.1 gene family for asthmatics allergic to HDM (P = 0.0186). It is remarkable-that only two cases in 36 asthmatics were allergic to ragweed and both of them predominantly used TCR V beta 1 gene families. The TCR V beta gene families predominantly used in asthmatics showed polyclonal expression in all normal controls and most asthmatics, but 5 asthmatics showed oligoclonal expression of TCR V beta 8 gene families.

CONCLUSIONS

TCRV beta 8 and TCR V beta 5.1 gene families may be associated with allergy to HDM in asthmatics. TCR V beta gene families in asthmatic peripheral blood showed oligoclonal expression tendency.