In vivo longitudinal analysis of a dominant TCR repertoire selected in human response to influenza virus

Recent studies have demonstrated biased usage of TCR V beta 17 and a high degree of diversity in J beta usage within the influenza virus matrix epitope (M.58-66)-specific CTL response. In contrast, in the course of a study on the cellular response to influenza A virus, we found preferential usage of V beta 17-J beta 2.2 rearrangement in an individual with an unexpectedly high number of CTL precursors (CTLp). We took advantage of such situation to study the longitudinal repertoire of the CD8+ T cell precursors. By limiting dilution analysis combined with the use of a clonotypic primer corresponding to the CDR3 region of this matrix-specific TCR V beta chain, the influenza-specific CTLp were shown to be stable for a period of 6 years. Overall, our results show that virus-specific CTLp can be directly monitored in vivo by molecular fingerprinting without in vitro restimulation. These findings might be extremely important for evaluation of the specific immune response to a given human pathogen.

CDR3 size analysis of T cell receptor V beta transcripts: follow-up study in a patient with T cell acute lymphoblastic leukemia

T cell acute lymphoblastic leukemia (T-ALL) is generally considered to be a clonal disorder arising as an expansion of committed lymphoid precursors. The generation of functional T cell receptor (TCR) genes involves DNA rearrangement processes. This predisposes immature lymphoid cells to abnormal rearrangements. Previous analysis of the TCR genes strongly suggested the clonal origin of human T-ALL. We present a sensitive clonal analysis of bone marrow TCR V beta transcripts in a case of T-ALL. This study allows the analysis not only of TCR V beta transcripts in tumor cells but also the temporal modification of the global TCR repertoire in the follow-up of clinical specimens from bone marrow aspirates. Moreover, we used clone-specific junctional region oligonucleotide probes corresponding to the clonal leukemic population for the molecular monitoring of the malignant clone throughout the clinical course of the disease. This molecular fingerprint appears to be a sensitive method to detect minimal residual disease. It shows that junctional regions of rearranged TCR beta genes corresponding to the tumor cells can also be detected at the time of the complete remission.