CD4 and Alzheimer disease: For NKT cells we investigated CD8 and CD4 subsets and CD56 expression (Fig. 5a) and found that while there were similar proportions of circulatory CD56+ NKT cells (Fig. 5b) and CD8+ NKT cells (Fig. 5c) between patients with LCH and healthy donors there were trends toward a higher proportion of CD4+ and a lower proportion of CD8−CD4− NKT cells in blood from patients with AD compared to NAD (Fig. 5c).