Figure 4.

Increased numbers of CD3^hiCD4^lo (CD8) T cells in aged follicles. (a) Confocal image (40×) of inguinal LN from a young NHP (A11R088, scale bar: 500 µm) showing the distribution of T cells and B cells within the LN (CD20—blue; CD4—red; and CD3—green). Zoomed areas from T‐cell zone (TCZ, scale bar: 7 µm) and a follicle (F, scale bar: 8 µm) with CD3^hiCD4^lo‐green and CD3^hiCD4^hi‐yellow. (b) The histocytometry gating scheme used to identify CD8 T cells. (c) The estimated cell density of follicular CD8 T cells in young (green, 6) and old (purple, 8) animals is shown. A GLMM via PQL was used. (d) The correlation between follicular CD8 and PD‐1^hi CD4 T cells in young animals is shown. Data from individual animals are shown. Each dot represents a follicle. A repeated measures correlation method was used for correlation analysis. Significant (<.05) p values are shown