Figure 3. Characterization of a small diverse T cell repertoire and transgenic expression of detected TCRs.

(A) PBMCs from donor 3 were stained with HLA-B8/IE-1_88–96 multimers. Dot plot shows the further analyzed CD8 and MHC multimer double-positive cell population. Cells were pre-gated on living lymphocytes (propidium iodide-negative and CD3-positive). (B) A PCR slide with single antigen-specific T cells from Figure 3A were FACS-isolated. TCR SCAN as described in Figure 1 and agarose gel electrophoresis of the resulting PCR products was performed. Upper row shows α-chain products matched with the respective β-chains in the lower row. White boxes indicate samples α- and matched β-chain-products derived from identical single cell samples. (C) The table summarizes the V- D- J- segment type and amino acid sequences of TCRs identified from CMV-multimer positive T cells in Figure 3A. In three independent experiments we identified nine different TCRs (TCR 3A-I) (D) Pie chart indicates the prevalence of identified TCRs from donor 3. Percentages represent incidence of respective TCR divided by total number of positive samples. (E) Sequences from TCR 3D, 3E and 3G were expressed in Jurkat76 T cells by retroviral gene transfer. Non-transduced (left FACS plot) and transduced Jurkat76 T cells were analyzed for expression of CD3 and MHC multimer binding.