Figure 2: Quantification of SOX2 expression in the human dentate gyrus.

The number of cells immunoreactive for SOX2 and NeuN in human dentate gyrus specimens was quantified by an independent investigator who was blinded to the experimental groups and normalized to the number of DAPI⁺ nuclei. Colocalization of SOX2 and NeuN was assessed using ImageJ plugins. Values are represented as the mean percentage of positive cells/total nuclei ± SEM. (a) The percentage of all SOX2⁺ cells (inclusive of NeuN⁺ and NeuN⁻ cells) is significantly increased in NDAN as compared to both MCI and AD. Within each column the percentage of SOX2⁺ cells that are negative for NeuN (grey) or positive for NeuN (black) is shown. (b) The percentage of cells that are positive for both SOX2 and NeuN (SOX2⁺/NeuN⁺) is significantly greater in NDAN as compared to MCI and AD. (c) The percentage of cells that express SOX2 but are negative for NeuN (SOX2⁺/NeuN⁻) are significantly increased in MCI as compared to AD and control and significantly increased in NDAN as compared to AD. Statistical significance was determined by ANOVA followed by multiple comparison procedures using the Holm-Sidak method. ^#p < 0.05; *p < 0.01. Linear regression analysis was performed to examine the relation between the percentage of SOX2⁺ cells (d), SOX2⁺/NeuN⁺ cells (e), SOX2⁺/NeuN⁻ cells (f) and cognitive function (MMSE score). Positive and significant correlations were found for all the regression performed, p < 0.05.