In order to explore the relationship between lung adenocarcinoma and tumor immunity, we analyzed the immune cell infiltration and found that SPP1 is expressed in many immune cells, such as macrophages, and the association of neutrophils and dendritic cells in lung adenocarcinoma with SPP1 was analyzed using the GEPIA website (Figure 11(a)P < 0.05), while SPP1 was involved in the infiltration of CD4+ T cells, macrophage and dendritic cells through the TIMER website (Figure 11(b), P < 0.05). The gene discussed is CD4; the disease is lung adenocarcinoma.