Comparison of the Jβ gene usage among different T cell receptor Vβ families in spleens of C57BL/6 mice

Abstract

To clarify whether there is a bias in the V-D-J combination of T cell receptor (TcR) genes, Jβ gene usage has been investigated in a total of 743 TcR β genes of Vβ2, Vβ8.2, and Vβ14 families expressed in C57BL/6 mouse spleens. Genes of TcR β chains, amplified by a reverse transcriptase-polymerase chain reaction, were individually cloned into plasmids. Cloned genes (61 to 106), randomly selected in each respective Vβ family from three different mice, were tested by means of hybridization with 12 oligo DNA probes which were designed to differentiate 12 murine functional Jβ gene segments. The results are enumerated below. (1) The Jβ2.6 gene segment was found to be most frequently used (Vβ2, 19.8%; Vβ8.2, 21.2%; and Vβ14, 19.2%). In contrast, usage of the Jβ1.6 gene segment was most infrequent (Vβ2.1.9%; Vβ8.2, 2.9%; and Vβ14, 0.5%); (2) High frequency of the Jβ2.1 gene segment and low frequency of the Jβ1.3 and Jβ1.5 gene segments were also observed; (3) The Jβ2 cluster was used in preference to the Jβ1 cluster (usages of the Jβ2 cluster: Vβ2, 67.8%; Vβ8.2, 65.9%; and Vβ14, 70.4%); and (4) These biases were generally common to all three Vβ families examined and differences among individual mice were mostly small. Considering these findings, we conclude that the TcR Jβ gene segments in C57BL/6 mice splenocytes are selected with a bias, but are selected independently of the Vβ families.