TCR�� (V��13.1J��NEW06) and �� (V��8.1J��1.2) cDNA clones derived from BC10 were inserted inhibitor Enzastaurin into TCR expression cassettes [26], and injected into fertilized CByB6F2 eggs to generate BC10 TCR transgenic mice. Two founders, BC10.1 and BC10.3 carrying both TCR�� and �� transgenes were derived, and lineage BC10.3 was chosen for further backcrossing based on its superior allelic exclusion rate (data not shown). The BC10.3 TCR transgenic (TCRtg) mice were backcrossed more than 10 times onto C57BL/6 (B6) background, and then mated once with CD45.1 mice (H-2b) so that the TCR transgenic T cells could be easily followed by anti-CD45.1 antibody staining. As shown in Figures 1A and 1B, >98% of the splenic CD8+ T cells (33.5% of total spleen cells) in these mice were COR93-specific and CD45.

1 positive as determined by staining with COR93-multimers and CD45.1 staining. As expected, they were phenotypically characterized as CD44?, CD62Lhigh, CD25?, CD69?, (Figures 1C and 1D) and fewer than 2% of them produced IFN�� or expressed Granzyme B (GrB) after 5 hours peptide stimulation in vitro (Figure 1E), indicating that they were in fact na?ve T cells. Figure 1 Expression and phenotype of HBV-specific CD8+ T cells in T cell receptor (TCR) transgenic mice. We also generated a lineage of transgenic mice whose CD8+ T cells express TCRs specific for the well-described Ld-restricted ENV28 epitope [27], [28]. The TCRs of these mice consist of V��4.1J��NEW and V��1.1J��2.5 chains cloned from CD8+ ENV28-specific CTL clone 6C2, whose functional properties have been extensively characterized [20], [27]�C[29].

Lineage 6C2.36 was chosen for further characterization and backcrossed onto the Balb/c background for at least 6 generations and then mated once with CD45.1 mice (H-2b). As shown in Figure 1F, approximately 83% of splenic CD8+ T cells (20% of total spleen cells) in lineage 6C2.36 are ENV28-specific and all of them were CD45.1 positive (Figure 1G). Again, virtually all the ENV28-specific CD8+ T cells were CD44?, CD62Lhigh, CD25?, CD69?, (Figures 1H and 1I), and they did not express IFN�� or GrB after peptide stimulation (Figure 1J), indicating that they are na?ve T cells. Na?ve HBV-specific CD8+ T cells expand vigorously in the liver but do not differentiate into effector T cells To examine the response of HBV-specific na?ve CD8+ T cells to hepatocellularly expressed HBV, we adoptively transferred 3�C5��106 COR93-specific na?ve CD8+ T cells from the spleen of BC10.

3 TCR transgenic donor mice into HBV transgenic lineage 1.3.32 recipient mice [19], [20]. Groups of 3�C4 mice were sacrificed at various time points after adoptive transfer, and their intrahepatic, lymph nodal, and splenic lymphocytes Drug_discovery were analyzed for the total number of COR93-specific CD8+ T cells and the extent to which they coexpress Granzyme B (GrB) and IFN�� either directly ex vivo or after in vitro stimulation by cognate COR93 peptide.