To find out how intrapleural injection of TEVs suppresses lung tumor growth, we examined tumor-infiltrating leukocytes (TILs) in LLC lung tumors and found that intrapleural injection of LLC-EVs significantly increased the frequencies of CD4+ T cells, CD8+ T cells and DCs among TILs but did not alter the frequencies of macrophages, NK cells, neutrophils and B cells (Figure 1H and Figure S1G). Here, CD4 is linked to neoplasm.