CD4 and Alzheimer disease: Compared with the ASD without AD group, children in the ASD with AD group had significantly higher levels of IgG, IgG1, IgG2, IgE, eosinophils (EO), and memory CD4+ T cells (CD4 + CD45RA-/CD4+), while having significantly lower levels of 45RA + CD4+ T cells, the percentage of 45RA + CD4+ T cell, naive CD4+ T cells, and the percentage of CD8 + CD38+/CD8+ T cells.