Figure 5

CD8⁺ T cell immune response to subdominant influenza epitopes in the younger and older populations. A) Comparison of CD8⁺ T cell response between control donors and geriatric donors based on IFNg secretion by ICS after three weeks of aAPC stimulation. Filled bars are control donors, lined bars are geriatric donors. B) Comparison of the number of responses to subdominant epitopes per donor, comparing control to geriatric donors. Positive responses were determined by ICS for IFNg secretion after three weeks of aAPC stimulation. C) Comparison of number of responses to subdominant epitopes per donor, comparing control to geriatric donors under the age of 80. D) Comparison of number of responses to subdominant epitopes per donor, comparing control to geriatrics over the age of 80. E) Comparison of responding donors to either no subdominant influenza-specific epitopes or 1 or more subdominant influenza-specific epitopes. This difference is statistically significant, p < 0.0026, by Fisher's exact test.