Sara van den Berg

147 6 T-cell dynamics in CMV expression of the senescence markers CD57 and KLRG-1, but low expression of the death receptor CD95 ( Figure 1H ). Collectively, these results show (1) that the increased frequency of advanced differentiation state CD8 + T-cells in CMV+ individuals is not simply explained by the sheer presence of large numbers of CD8 + CMV-specific T-cells, and (2) that part of the CMV-specific CD8 + T-cells cluster separately. Figure 2. Altered expression of lifespan-associated markers by CD4 + T EM/EMRA cells in CMV infection. A. Representative flow cytometric plots for gating of Ki-67 and Bcl-2 expression. Graphs represent percentage of positive cells for Ki-67 and Bcl-2 in CMV- and CMV+ individuals by CD4 + and CD8 + T-cells, measured per memory subpopulation. B, C. Principal component (PC) analysis of CD4 + ( B ) and CD8 + ( C ) T-cells based on lifes- pan-associated markers KLRG-1, CD57, CD28, Ki-67 and Bcl-2 per memory subpopulation. Blue dots represent CMV- individuals, red dots represent CMV+ individuals. D. Comparison of expression of Ki-67 and Bcl-2 by the total memory CD8 + T-cell pool of CMV+ individuals and by CMV-specific CD8 + T-cells, measured per memory subpopulation. E. PC analysis of CD8 + T-cells based on lifespan-associated markers KLRG-1, CD57, CD28, Ki-67 and Bcl-2 per memory subpopulation. Bars in A and D represent medians. Differences between CMV- and CMV+ individuals were tested by Mann-Whitney U test. Stars indicate significant differences as follows: * P -value <0.05, ** P -value <0.01, *** P -value <0.001, *** P -value <0.0001.