FIG. 5.

Fas (CD95) expression on the surfaces of lymphocytes during measles. (A and B) Mean percentages of CD4 (A) and CD8 (B) T cells from measles patients and control children with surface expression of Fas. Fas expression was determined by flow cytometry of freshly isolated CD4⁺ and CD8⁺ lymphocytes gated by forward and side scatter. The number of samples in each group is indicated at the base of each bar. The error bars indicate the standard error of the mean. ∗∗∗∗, P < 0.0001; ∗∗∗, P < 0.001; ∗∗, P < 0.01; ∗, P < 0.05 (Mann-Whitney U test). (C) Correlation of percent Fas-positive CD4 T cells at entry with lymphocyte death in culture. P = 0.0067 (Spearman rank correlation).