Ricerc@Sapienza

Although clonal expansion is a hallmark of adaptive immunity, the location(s) where antigen-responding T cells enter cell cycle and complete it have been poorly explored. This lack of knowledge stems partially from the limited experimental approaches available. By using Ki67 plus DNA staining and a novel strategy for flow cytometry analysis, we distinguished antigen-specific CD8 T cells in G0 , in G1 and in S-G2 /M phases of cell cycle after intramuscular vaccination of BALB/c mice with antigen-expressing viral vectors.