In order to explore the molecular basis of peripheral immune cells and the features of adaptive immune repertoire at a single cell level, we used 10X Genomics 5’ RNA, T cell receptor (TCR) and B cell receptor (BCR) sequencing technology of 36,849 peripheral blood mononuclear cells (PBMCs) from patients with AD and normal controls (NC), along with cell ranger standard analysis to define immune cell subsets, reveal the proportion of immune cell subsets and gene transcription states, and identify the key genes and pathways. This evidence concerns the gene BCR and Alzheimer disease.