T-Cell Receptor Variable γ Chain Gene Expression in the Interaction between Rat γδ-Type T Cells and Heat-Shock Protein 70-Like Molecule

We previously reported that rat T-cell receptor (TCR) Vδ6 of T-cell hybridomas was preferentially involved in recognition of the cell surface-expressed 70 kDa rat heat-shock cognate (hsc70, a constitutively expressed member of the hsp 70 family) protein-like molecule (#067 molecule). In the present study, we analyzed usage of the TCR Vγ family of #067-restricted T-cell hybridomas. Our data indicated that most of these hybridomas expressed transcripts of TCR Vγ1 and/or Vγ2. However, some of the Vγ2 transcripts were out-of-frame, suggesting that the TCR Vγ1 family may be important for the recognition of #067-defined molecules. TCR Vγ1 transcripts were detected in not only #067-restricted T-cell hybridomas, but #067-non restricted ones as well. However, V-J nucleotide sequences of #067-restricted and #067-non restricted T-cell hybridomas suggested that #067-restricted T-cell hybridomas showed limited insertion of nucleotide stretch as compared with #067-non restricted ones. In terms of amino acids, only one amino acid was added in #067-restricted T-cell hybridomas, whereas two or three amino acids were added in #067-non restricted ones. These data suggest that the heterodimer of the TCR relatively short stretch form of Vγ1 molecule and TCR Vδ6 may participate in recognition of the #067 molecule.