Protein antigen combination for detection of Alzheimer's disease and application thereof

An antigen combination for diagnosis of early Alzheimer's disease, wherein the antigen combination comprises:

• (a) small EDRK-rich factor 2 (SERF2), galectin-1 (LGALS1), lysine-specific demethylase 4D (KDM4D), and adenosine deaminase RNA-specific B1 (ADARB1), wherein at least one of SERF2, LGALS1, KDM4D, and ADARB1 is labeled with a tag for purification or identification;
• or (b) double C2-like domain-containing protein alpha (DOC2A), LGALS1, KDM4D, and ADARB1, wherein at least one of DOC2A, LGALS1, KDM4D, and ADARB1 is labeled with a tag for purification or detection;
• wherein SERF2 comprises the amino acid sequence set forth in SEQ ID NO:
• 6, LGALS1 comprises the amino acid sequence set forth in SEQ ID NO:
• 2, KDM4D comprises the amino acid sequence set forth in SEQ ID NO:
• 7, ADARB1 comprises the amino acid sequence set forth in SEQ ID NO:
• 9, DOC2A comprises the amino acid sequence set forth in SEQ ID NO:
• 1.