Fig. 4.

Intravenous vaccination is able to recruit low numbers of antigen-specific CTL precursors. a CD45.1 WT-B6 mice received 200–2000 naïve TnTR1 CTLs followed by vaccination with pam-Trp1/TriVax administered i.v and percentages of TnTR1 cells (CD45.2) and endogenous responses (CD45.1) were assessed in the Trp1 tetramer + populations. b Number of Trp1 tetramer⁺ CTL precursors in naïve WT-B6 and Trp1-KO splenocytes. c, d OT-I mice received 20–20,000 TnTR1 naïve CTLs followed by vaccination with 2 doses of pam-Trp1/TriVax (administered 21 days apart) injected i.v. and percentages of TnTR1 cells in blood were measured 7 days after each vaccination. Results are presented as individual mice (each symbol) with the mean ± SD for each group. Numbers below the tetramer + gates represent the percentage positive CD8 T cells. These experiments were repeated 2–3 times with similar results