A complete absence of SIV-specific CD8+ T cells in most GCs at 21 dpi whilst during chronic infection there are equal numbers of SIV-specific CD8+ T cells in GC and non-GC follicular areas [20] suggests that during early infection, there is a temporal delay from the formation of nascent follicles and the entry of SIV-specific CD8+ T cells. This evidence concerns the gene CD8A and infection.