Rearranged T lymphocyte antigen receptor genes as markers of malignant T cells

We have recently cloned a number of canine T cell receptor (TCR) V beta gen es using degenerate oligonucleotides, From the DNA sequences of the resulti ng clones and the canine V beta gene sequences in the literature, seven dis tinct canine TCR V beta genes were identified. V beta specific PCR primers were designed for each of the seven TCR V beta genes such that under define d conditions, each primer could only amplify a specific TCR V beta gene in conjunction with the same 3' constant region (CP) primer. By performing RT- PCR on RNA derived from a source containing T lymphocytes, the presence and expansion of T cells expressing a particular V beta gene could be detected . Moreover, the clonality or diversity of a T cell population under analysi s could be easily determined by the VDJ junctional sequence of the amplifie d V beta PCR product, in the form of a "DNA fingerprint". These findings ha ve been used to detect canine T cell lymphoma, and could potentially be use d to monitor the remission of T cell malignancies in response to treatment. (C) 1999 Published by Elsevier Science B.V. All rights reserved.