Limited heterogeneity of T-cell receptor V beta gene expression in the early stage of insulitis in NOD mice.

Non-obese-diabetic (NOD) mice spontaneously develop type I diabetes. The disease starts with T cells infiltrating the islets of Langerhans. We therefore examined the T-cell receptor (TCR) V beta region repertoire in islet infiltrates from individual female NOD mice from 4 to 10 week old by polymerase chain reaction (PCR) using V beta 1-V beta 17 specific oligonucleotides. The study revealed a limited heterogeneity of TCR V beta transcripts with a predominance of V beta 1 at the onset of insulitis, i.e. at 4 weeks of age. The TCR VDJ beta sequences of the V beta 1 PCR fragments were identical in most of the individual mice. Among several different mice, similarities in the beta-junctional regions were detected. In contrast, a large heterogeneity of TCR V beta usage was found in mice with advanced insulitis, i.e., from 6 weeks of age on. Thus, these data suggest a limited heterogeneity of TCR V beta usage with a predominance of V beta 1 at the initiation phase of the disease.