Memory responses triggered by vaccination with homologous and heterologous prime boost regimens utilizing Ad4-CSP and Ad5-CSP in Ad naïve mice. Splenocytes (B-C) and PBMCs (D-E) were collected two weeks after final vaccination. Cells were stained for CD62L-V450, CD127-PerCP Cy5.5, and CSP (NYD) tet-PE. CSP specific central memory T cells were determined as CD62L+ CD127+ cells that are tet+ and effector memory cells are CD62Llo CD127+ cells that are tet+. Provided above is an example of gating (A). Bars represent ± standard error. Statistical analysis was completed using One Way ANOVA with Student-Newman-Keuls post-hoc test, **, *** denotes significance over naïve, P < 0.01, P < 0.001.