In addition, among the biological functions related to these proteins, 15 differentially expressed proteins (DEFA1, S100A9, LCN2, S100A8, IGHM, HIST1H2BK, IGJ, PRDX2, ACTB, FGA, CD14, HP, FCGR3A, TIMP1, APOE), classified in infectious disease, were significantly associated with viral infection (p-value: 2.58E-05). The gene discussed is APOE; the disease is viral infectious disease.